HPS Weekly Report

4 April 2013Volume 47 No. 2013/14ISSN 1753-4224 (Online)

Contents

CURRENT NOTES

• Additionalconfirmedcasesofnovelcoronavirus

• Humancasesofinfluenzaatthehuman–animalinterface,2012

• Scottish Vaccine Update-Issue22

• FSAUK-widesurveyofbeefproducts

• Schmallenberg(SBV)update• Healthaspectsofairpollution

-WHOreviewofevidence• Environmentalincidents-

SEISSreports

pages 104 - 106

SURVEILLANCE REPORTS

• QuarterlyreportonthesurveillanceofStaphylococcus aureusbacteraemiasinScotland,October–December2012

pages 107 - 110

• QuarterlyreportonthesurveillanceofClostridium difficileinfection(CDI)inScotland,October–December2012

pages 111 - 116

NOTIFIABLE TABLE

to 22/03/2012

pages 117 - 118

CURRENT NOTES

Correspondence to:The Editor, HPS Weekly ReportHPSMeridian Court5 Cadogan StreetGlasgow, G2 6QEScotland

T 0141-300 1100 F 0141-300 1172

E NSS.HPSWReditor@nhs.net http://www.ewr.hps.scot.nhs.uk/

Printed in the UKHPS is a division of the NHS National Services Scotland Registered as a newspaper at the Post Office © HPS 2013

Additional confirmed cases of novel coronavirus

47/1401 The European Centre for Disease Prevention and Control (ECDC) published an epidemiological update on 22 February 2013, since which time four new confirmed cases of novel coronavirus (nCoV) infection have been reported worldwide, totalling 17 cases and including eleven deaths. Three of the four recent cases have been reported by the Ministry of Health of Saudi Arabia to WHO on:

• 6 March 2013: a 69 year old male, with no recent history of travel or contact with a confirmed case, hospitalised on 10 February 2013 and who died on 19 February.

• 12 March 2013: a 39 year old male reported to have developed symptoms on 24 February and who died on 2 March while hospitalised. Potential exposures are under investigation.

• 23 March 2013: a patient with mild symptoms diagnosed with nCoV infection and hospitalised, who has since recovered. The mode and source of transmission has not been identified, but the case is known to be a contact of the above case reported on 12 March.

The fourth case was reported on 25 March by the Robert Koch Institute (RKI) and is the second imported case to be reported in Germany. The patient, a 73 year old male with underlying clinical conditions, had been hospitalised in United Arab Emirates and transferred to a hospital in Germany for specific clinical care where subsequent diagnosis of nCoV infection was confirmed. Despite intensive care treatment the patient died on 26 March. Contact tracing and investigations are underway by German public health authorities.

Since the start of reporting, six cases have been diagnosed and cared for in Europe. Three cases (two in Germany and one in the UK) came to Europe as part of transfer for care from countries in the Arabian Peninsula where they acquired their infection. A fourth case became unwell while in the Arabian Peninsula, but may have acquired his infection in either Pakistan or the Arabian Peninsula, before travelling to the UK. Extensive contact tracing has been undertaken around the first two UK cases and first German case, by respective national public health authorities. To date, this has revealed two cases occurring though human-to-human transmission in the UK. Testing of other persons as recommended by WHO and ECDC has not revealed additional cases.

Though the number of nCoV infections has increased this last month, most reported cases continue to be associated with the Arabian Peninsula, where contact tracing and epidemiological investigations by public health authorities continue in order to identify the possible source(s) of infection.

The ECDC update of the rapid risk assessment for the EU provided on 19 February and its recommendations remain valid. ECDC has also published a ‘Public Health Development’ highlighting recent updated surveillance and clinical guidance from WHO and providing ECDC advice on their application by EU member states. [Source: ECDC News Release, 27 March 2013. http://ecdc.europa.eu/en/press/news/Lists/News/ECDC_DispForm.aspx?List=32e43ee8%2De230%2D4424%2Da783%2D85742124029a&ID=873&RootFolder=%2Fen%2Fpress%2Fnews%2FLists%2FNews]

The HPS Infection Prevention and Control Precautions as well as updated versions of Laboratory Guidance algorithm, Information for Microbiologists and Virologists and Case Management and Contact follow-up algorithms are available at the HPS web page on coronavirus at http://www.hps.scot.nhs.uk/resp/coronavirus.aspx?subjectid=CA.

Human cases of influenza at the human–animal interface, 2012

47/1402 The current issue of the World Epidemiological Record describes the epidemiology of the 32 laboratory-confirmed human infections with highly pathogenic avian influenza A(H5N1) virus that were reported to WHO from six countries during 2012, and summarises the information on other zoonotic influenza infections - A(H3N2) variant, A(H1N1), A(H1N2) and A(H7N3) - reported in 2012 in humans.

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In 2012, the number of laboratory-confirmed human cases of A(H5N1) virus infection declined, despite continued widespread circulation of the virus in poultry in some countries. In total, 32 human cases were reported, down from 62 in 2011, 48 in 2010 and 73 in 2009. Of the 32 cases of A(H5N1), 11 occurred in Egypt, nine in Indonesia, four in Viet Nam, three in Cambodia, three in Bangladesh and two in China.

According to information from the Food and Agriculture Organization of the United Nations (FAO), influenza A(H5N1) virus is circulating endemically in poultry in Bangladesh, China and Viet Nam. Egypt and Indonesia have officially declared the H5N1 virus endemic in poultry, and a recent study from Institut Pasteur, Cambodia, suggested that the virus is circulating endemically in poultry in Cambodia. All countries reporting human cases in 2012 also reported human cases in previous years.

The full report can accessed at http://www.who.int/entity/wer/2013/wer8813/en/index.html.

Scottish Vaccine Update - Issue 22

47/1403 The Scottish Vaccine Update issued by Health Protection Scotland provides current information and practical advice about immunisation policy, practice and vaccine supply in Scotland for front line health professionals.

The current issue, published on 28 March, includes preliminary information on the uptake of the vaccination against pertussis in pregnant women in Scotland. This and previous issues of the update can be accessed at http://www.hps.scot.nhs.uk/immvax/publications.aspx.

FSA UK-wide survey of beef products

47/1404 Further test results from the first two phases of the Food Standards Agency’s UK-wide sampling programme of beef products were confirmed on 26 March. The results showed 352 out of 362 samples were negative for the presence of both horse and pig DNA.

Of the remaining 10 samples, three were confirmed as containing pig DNA at or above the 1% threshold, as identified in the FSA’s statement on 8 March. The three products were ASDA Spaghetti and Meatballs; ASDA Beef Cannelloni; and Apetito Beef Lasagne. A further two, a Whitbread burger and IKEA meatballs, had been confirmed as containing horse DNA at or above the 1% threshold. Both of these products had been previously reported by the food industry’s own results and are already included in the table on the FSA’s website. The results of the last five samples were being challenged and awaiting the outcome of further independent tests. If the products are found to be positive for contamination above the 1% threshold, the results will be reported on the FSA website.

The purpose of the sampling programme is to get an accurate picture of the potential scale of contamination of beef products on high streets and in the catering supply chain across the UK. The findings of the survey, carried out by 28 local authorities on behalf of the FSA, are consistent with those from the tests carried out by the food industry. The results confirm that the contamination and adulteration of beef products, with horse or pork meat, has been limited to a relatively small number of products.

The FSA’s view remains that consumers should be able to trust what they see on food labels and the Agency is working with the local authorities where positive samples have been identified, with a view to taking enforcement action where necessary. [Source: FSA News Release, 26 March 2013. http://www.food.gov.uk/news-updates/news/2013/mar/survey]

Schmallenberg (SBV) update

47/1405 Farmers have been urged to remain vigilant after the first evidence emerged that Schmallenberg Virus (SBV) was circulating in Scotland in 2012.

Eight cows in a dairy herd at the Barony campus of Scotland’s Rural College in Dumfries and Galloway have tested positive for SBV antibodies, indicating exposure to the virus in 2012, although at a low prevalence. No deformed calves have yet been born to the 160-strong herd on the farm. The animals were homebred and no animals had been added to the herd from outside Scotland.

The virus - which can cause abortions and birth defects in animals - was first detected in Southern England in January 2012. Although a small number of animals that had recently moved into Scotland have previously tested positive for SBV antibodies, this is the first evidence that suggests exposure to infected midges in Scotland.

Biobest and SAC Consulting Veterinary Services, part of SRUC, (in conjunction with NFU Scotland) are about to begin a Schmallenberg surveillance scheme in Scotland. They are identifying dairy farms that would be willing to take part in the testing of bulk milk to help flag up any spread of the virus across the country.

SBV was first identified in 2011 and has been detected in a number of countries including the Netherlands, Germany, Belgium, and France as well as in England, Wales and Ireland. SBV is not notifiable in the UK and no restrictions are placed on infected premises. [Source: Scottish Government News Release, 27 March 2013. http://www.scotland.gov.uk/News/Releases/2013/03/Schmallenberg27032013]

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Health aspects of air pollution - WHO review of evidence

47/1406 The World Health Organization Regional Office for Europe has recently published its Review of evidence on health aspects of air pollution – REVIHAAP (First results).

This document presents answers to 22 questions relevant for the review of European policies on air pollution and addressing health aspects of these policies. The answers were developed by a large group of scientists engaged in the WHO REVIHAAP project. The experts reviewed and discussed the newly accumulated scientific evidence on health effects of air pollution, formulating science-based conclusions and drafting the answers. Extensive rationale for the answers, including the list of key references, will be provided in the final report from the project. The review concludes that a considerable amount of new scientific information on health effects of particulate matter, ozone and nitrogen dioxide, observed at levels commonly present in Europe, has been published in the recent years. This new evidence supports the scientific conclusions of the WHO Air Quality Guidelines, last updated in 2005, and indicates that the effects can occur at air pollution concentrations lower than those serving to establish the 2005 Guidelines. It also provides scientific arguments for the decisive actions to improve air quality and reduce the burden of disease associated with air pollution in Europe.

This publication arises from the project REVIHAAP and has been co-funded by the European Union. It can be accessed at http://www.euro.who.int/en/what-we-do/health-topics/environment-and-health/air-quality/publications/2013/review-of-evidence-on-health-aspects-of-air-pollution-revihaap.

Environmental incidents - SEISS reports

47/1407 The Scottish Environmental Incident Surveillance System (SEISS) recorded the following incidents in the past week:

• On 26 March, a major fire broke out at a school in Glasgow. Up to 60 children were evacuated to a local community centre. At the height of the blaze, 55 firefighters were involved. (http://www.bbc.co.uk/news/uk-scotland-glasgow-west-21940354; http://www.strathclydefire.org/news--campaigns/news/2013/march/ongoing-blaze-in-glasgow-school.aspx).

• On 1 April, a grassland fire broke out near Fort William. At one point the fire and smoke spread for over three miles (http://www.bbc.co.uk/news/uk-scotland-highlands-islands-21999542). This was one of a number of current such incidents causing concern (http://www.firescotland.gov.uk/news-campaigns.aspx).

For more detailed information on SEISS please refer to the SEISS web-site (http://www.hps.scot.nhs.uk/enviro/ssdetail.aspx?id=107) or contact either Ian Henton or Colin Ramsay at HPS on 0141 300 1100.

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Surveillance Report

Quarterly report on the surveillance of Staphylococcus aureus bacteraemias in Scotland, October – December 2012

Prepared by: Health Protection Scotland

Executive summary

• This report provides a summary of Staphylococcus aureus (S. aureus) bacteraemia data for the fourth quarter of 2012 (October to December 2012) in 15 NHS boards. This includes data on both meticillin resistant S. aureus (MRSA) and meticillin sensitive S. aureus (MSSA) bacteraemias, including comparison to data of preceding quarters.

• Altogether, 379 new S. aureus bacteraemia cases were reported to Health Protection Scotland (HPS) during this period. This is a decrease of 7.1% compared with the same quarter last year (October to December 2011) when 408 cases were reported and it is the second equal lowest number of cases reported since the start of the mandatory S. aureus bacteraemia surveillance programme.

• In the last year, January 2012 to December 2012, 1509 episodes of S. aureus bacteraemia were reported to HPS. This represents a decrease of 6.2% on the previous year, January 2011 to December 2011, when 1609 episodes were reported.

• The overall rate of S. aureus bacteraemias for Scotland was 29.9 S. aureus bacteraemia cases per 100 000 acute occupied bed days (AOBDs). This represents to a small increase of 1.6% compared to the previous quarter (from 29.4 to 29.9). This is, nonetheless, the third lowest S. aureus bacteraemia rate reported since the start of the mandatory S. aureus bacteraemia surveillance programme.

• In comparison with the same quarter of 2011, the overall S. aureus bacteraemia rate for Scotland has decreased by 7.1%, from 32.1 to 29.9 per 100 000 AOBDs.

• The number and rate of MRSA bacteraemias reported in the period October to December 2012 equalled the fifth lowest of all quarters reported since the start of this surveillance programme with 52 cases and 4.1 per 100 000 AOBDs.

• During this quarter, the S. aureus, MRSA and MSSA bacteraemia rates at all NHS boards were within or below the 95% confidence limits on the funnel plots.

• The national surveillance programme reports on S. aureus bacteraemias arising three months or longer before publication of this report. It remains essential therefore that it is complemented by more contemporaneous local monitoring of S. aureus bacteraemias by NHS boards themselves.

1. Introduction

Staphylococcus aureus (S. aureus) is a gram positive bacterium which colonises the nasal cavity of about 30% of the healthy population. Although this colonisation is usually harmless, S. aureus may cause serious infections. These infections are commonly associated with healthcare interventions, often because of failures to implement infection prevention methods. As a result, both meticillin sensitive and meticillin resistant S. aureus (MSSA and MRSA) remain endemic in many UK hospitals, causing a range of infections. Amongst the most serious of these are bacteraemias.

The Health Protection Scotland (HPS) S. aureus bacteraemia surveillance programme monitors the occurrence of S. aureus bacteraemias amongst all patients in Scotland. It includes S. aureus bacteraemias occurring in patients who have been in contact with the healthcare system (in both acute and non-acute hospitals, as well as in primary care settings) and those who have acquired S. aureus bacteraemias in the community, without any healthcare contacts.

The surveillance programme in Scotland includes data on both MRSA and MSSA bacteraemias. Many other countries restrict surveillance of S. aureus bacteraemias to those caused only by MRSA.

This quarterly report is concerned with the incidence of S. aureus bacteraemias in Scotland and within individual

NHS boards. HPS publishes an annual report on S. aureus bacteraemias in Scotland.1 This report contains further analyses of S. aureus data, including trends in S. aureus bacteraemias.

The quarterly S. aureus bacteraemia data produced by HPS are based on interim data for both bed occupancy and incident S. aureus bacteraemias. These data are subject to revision as finalised data become available. Therefore there may occasionally be minor numeric discrepancies between reports, reflecting the availability of such updated data.

Finally, it should be noted that the national S. aureus bacteraemia surveillance programme contains information on bacteraemias which occurred at least three months and possibly up to six months, before this report was published. It is therefore imperative that NHS boards have their own local S. aureus bacteraemia surveillance systems to alert local teams to the need for possible early action. This surveillance report does not replace local monitoring of S. aureus bacteraemias by NHS boards’ infection control teams.

2. Methods

Full details of the data source and the definitions used to generate this report are published on the HPS website.2 The scaling factor used in reporting incidence rates in this report is now ‘per 100 000 bed days’ instead of the previously used ‘per 1000 bed days’.

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Identification of outliers Comparisons of NHS boards’ S. aureus bacteraemia, MRSA and MSSA rates are shown using funnel plots.3 These are scatterplots of the observed S. aureus bacteraemia events, measured as rates, plotted against their precision, indicated by the number of acute occupied bed days. The plots in this report show the upper and lower 95% confidence limits as curved lines. If an individual NHS board’s rate was outwith the 95% confidence limit, this would be regarded as an outlier, suggesting that that NHS board had a S. aureus bacteraemia rate which was significantly different to other NHS boards.

Analysis of trendsAnalysis of trends in the rates of S. aureus bacteraemias was carried out within an over-dispersed Poisson regression model. The regression included terms for NHS board, year and quarter. Model checking was performed using residual plots and these demonstrated that the model assumptions were reasonable. Trend analyses were based on the latest 31 quarters of data.

3. Results

3.1. Surveillance dataDuring the period October to December 2012, HPS received reports of S. aureus bacteraemias from 22 diagnostic laboratories in 14 NHS boards as well as from the Scottish MRSA Reference Laboratory.

The total number of S. aureus bacteraemia cases identified in Scotland was 379, of which 52 were MRSA bacteraemias (13.7%) and 327 were MSSA bacteraemias (86.3%) as shown in Table 1. The total numbers of S. aureus bacteraemias in Scotland increased by 3.3% compared with the previous quarter (July to September 2012) when 367 S. aureus bacteraemia cases were recorded. In that quarter 33 (9.0%) were due to MRSA and 334 (91.0%) to MSSA.

The overall S. aureus bacteraemia rate for Scotland during this quarter, October to December 2012, was 29.9 per 100 000 AOBDs. This is a 7.1% decrease on the overall rate for Scotland from the corresponding quarter in the previous year. This represents the second equal lowest number of cases and third lowest rate of S. aureus bacteraemias since the incorporation of MSSA bacteraemias into this surveillance system.

TABLE 1: Quarterly numbers of S. aureus bacteraemias (MRSA and MSSA) in Scotland*Quarter MRSA

bacteraemias**(n)

MSSA bacteraemias**

(n)

S. aureus bacteraemias**

(n)

Acute Occupied Bed Days (AOBDs)

MRSA bacteraemias per 100 000

AOBDs

MSSA bacteraemias per 100 000

AOBDs

S. aureus bacteraemias per 100 000

AOBDsApr 05-Jun 05 221 375 596 1327034 16.7 28.3 44.9Jul 05-Sep 05 247 511 758 1325690 18.6 38.5 57.2Oct 05-Dec 05 264 422 686 1342990 19.7 31.4 51.1Jan 06-Mar 06 274 464 738 1390111 19.7 33.4 53.1Apr 06-Jun 06 252 358 610 1362072 18.5 26.3 44.8Jul 06-Sep 06 212 389 601 1329262 15.9 29.3 45.2Oct 06-Dec 06 227 300 527 1339822 16.9 22.4 39.3Jan 07-Mar 07 249 364 613 1378926 18.1 26.4 44.5Apr 07-Jun 07 215 415 630 1344984 16.0 30.9 46.8Jul 07-Sep 07 210 459 669 1308607 16.0 35.1 51.1Oct 07-Dec 07 207 417 624 1321950 15.7 31.5 47.2Jan 08-Mar 08 198 386 584 1382550 14.3 27.9 42.2Apr 08-Jun 08 180 397 577 1335033 13.5 29.7 43.2Jul 08-Sep 08 150 382 532 1299840 11.5 29.4 40.9Oct 08-Dec 08 161 400 561 1334459 12.1 30.0 42.0Jan 09-Mar 09 170 386 556 1353145 12.6 28.5 41.1Apr 09-Jun 09*** 143 392 535 1319537 10.8 29.7 40.5Jul 09-Sep 09*** 101 384 485 1291267 7.8 29.7 37.6Oct 09-Dec 09*** 119 362 481 1307957 9.1 27.7 36.8Jan 10-Mar 10*** 116 388 504 1333296 8.7 29.1 37.8Apr 10-Jun 10*** 79 343 422 1293241 6.1 26.5 32.6Jul 10-Sep 10*** 73 367 440 1261334 5.8 29.1 34.9Oct 10-Dec 10*** 81 388 469 1275500 6.4 30.4 36.8Jan 11-Mar 11*** 69 355 424 1303324 5.3 27.2 32.5Apr 11-Jun 11*** 52 342 394 1276732 4.1 26.8 30.9Jul 11-Sep 11*** 48 335 383 1253167 3.8 26.7 30.6Oct 11-Dec 11*** 50 358 408 1270305 3.9 28.2 32.1Jan 12-Mar 12*** 48 331 379 1292828 3.7 25.6 29.3Apr 12-Jun 12*** 54 330 384 1271413 4.2 26.0 30.2Jul 12-Sep 12*** 33 334 367 1248530 2.6 26.8 29.4Oct 12-Dec 12*** 52 327 379 1269546 4.1 25.8 29.9

* Figures within this report are provisional and may be subject to update from reporting laboratories.** Mandatory reporting of MSSA bacteraemias was introduced in July 2006 and MSSA were validated back to 1 April 2005.*** Reporting of National Waiting Times Centre (NWTC) data began in April 2010 however retrospective data for the NWTC for the period April 2009 to March

2010 have now been included within the Scottish data.

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TABLE 2: Total number of S. aureus bacteraemia cases this quarter and annual rates of S. aureus bacteraemias in 15 NHS boards in Scotland

October 2012 to December 2012 October 2011 to September 2012NHS board AOBDs S. aureus

bacteraemias (n)

S. aureus bacteraemia rate

per 100 000 AOBDs

AOBDs S. aureus bacteraemias

(n)

S. aureus bacteraemia rate per

100 000 AOBDsAyrshire & Arran 88669 22 24.8 352748 97 27.5Borders 19183 5 26.1 90649 34 37.5Dumfries & Galloway 33407 9 26.9 131701 32 24.3Fife 61652 17 27.6 236733 129 54.5Forth Valley 54483 26 47.7 209444 77 36.8Grampian 132869 43 32.4 528572 146 27.6Greater Glasgow & Clyde 362020 100 27.6 1472272 427 29.0Highland 62079 14 22.6 251142 58 23.1

Lanarkshire 123381 36 29.2 488788 133 27.2Lothian 199559 70 35.1 802147 246 30.7National Waiting Times Centre 12696 1 7.9 48408 5 10.3

Orkney 3777 1 26.5 15529 2 12.9Shetland 3703 1 27.0 13616 4 29.4Tayside 106367 34 32.0 414320 145 35.0Western Isles 5701 0 0.0 27007 3 11.1Scotland 1269546 379 29.9 5083076 1538 30.3

This quarter, October to December 2012, had the fifth lowest equal number and rate of MRSA bacteraemias of any quarter since the start of the mandatory S. aureus bacteraemia surveillance programme.

The total numbers of S. aureus bacteraemia cases and the S. aureus bacteraemia rates for each NHS board during this quarter, October to December 2012, are listed in Table 2, which also indicates the numbers and rates of S. aureus bacteraemia in the preceding year, October 2011 to September 2012. All historic data of cases, AOBDs and S. aureus bacteraemia rates for each NHS board are included in the online appendix 2 (at http://www.hps.scot.nhs.uk/haiic/sshaip/publicationsdetail.aspx?id=30248).

3.2. Comparison of NHS boards’ rates Figure 1a shows a funnel plot of S. aureus bacteraemia rates for individual NHS boards for this quarter, Figures 1b and 1c show similar funnel plots for MRSA and MSSA bacteraemias, respectively. They show that none of the S. aureus bacteraemia rates in NHS boards was above the upper 95% confidence limit.

FIGURE 1a: Funnel plot of S. aureus bacteraemia rates for all NHS boards in Scotland against acute occupied bed days (x100 000), 1 October 2012 to 31 December 2012. Note that NHS Orkney and NHS Shetland overlap in the figure below

0

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FIGURE 1b: Funnel plot of MRSA bacteraemia rates for all NHS boards in Scotland against acute occupied bed days (x100 000), 1 October 2012 to 31 December 2012. Note that there are overlaps in the figure below involving NHS Fife/NHS Highland and NHS Dumfries & Galloway/NHS NWTC/NHS Orkney/NHS Shetland/NHS Western Isles

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FIGURE 1c: Funnel plot of MSSA bacteraemia rates for all NHS boards in Scotland against acute occupied bed days (x100 000), 1 October 2012 to 31 December 2012. Note that NHS Orkney and NHS Shetland overlap in the figure below

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Key to NHS boardsAA Ayrshire & Arran FV Forth Valley LN Lanarkshire SH ShetlandBR Borders GGC Greater Glasgow & Clyde LO Lothian TY TaysideDG Dumfries & Galloway GR Grampian NWTC National Waiting Times Centre WI Western IslesFF Fife HG Highland OR Orkney

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3.3. Identification of trends

The overall quarterly rates for Scotland are shown in Figure 2. A Poisson regression analysis of trends in the S. aureus bacteraemia rate between April 2005 and December 2012 was carried out. This showed a significant year on year reduction in the rate of S. aureus bacteraemias for NHSScotland. This was estimated to be 7.5% per year (95% CI: 6.4% to 8.6%). The rate of MRSA bacteraemias also showed a significant year on year reduction estimated at 21.1% (95% CI: 18.8% to 23.3%) as did the rate of MSSA bacteraemias which was estimated to be 2.2% per year (95% CI: 0.7% to 3.6%). The S. aureus, MRSA and MSSA rates for Scotland are shown as rolling four-quarter rates in Figure 3. Similar rolling four-quarter rates for all NHS Boards are included in the online appendix 1 (at http://www.hps.scot.nhs.uk/haiic/sshaip/publicationsdetail.aspx?id=30248).

FIGURE 2: Overall quarterly S. aureus bacteraemia rates for Scotland (per 100 000 total AOBDs) with linear trend line for 28 quarters of mandatory surveillance covering the period 1 April 2005 to 31 December 2012

S. aureus bacteraemia per 100 000 AOBDs

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Linear (S. aureus bacteraemia per 100 000 AOBDs)

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FIGURE 3: Rolling four quarter rates of S. aureus, MRSA and MSSA bacteraemia for Scotland (per 100 000 total AOBDs) with confidence intervals (CI) from April 2005

Four quarters endingS. aureus rate S. aureus_lower CI S. aureus_upper CI

MRSA rate MRSA_lower CI MRSA_upper CIMSSA rate MSSA_lower CI MSSA_upper CI

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4. Discussion

This report covers S. aureus bacteraemia surveillance data for the period October to December 2012. Unlike the national surveillance schemes in many other countries, it includes both MRSA and MSSA bacteraemias.

A number of important caveats associated with the data in this report must be highlighted. These include the use of estimated denominator data, numerator data being self-reported by participating laboratories, the inclusion of some S. aureus bacteraemias which may be community-acquired and only diagnosed on admission to hospital and possible multiple reports on patients due to non-compliance with treatment or treatment failure.

Altogether, 379 cases of S. aureus bacteraemia were identified during this period. This represents to an increase of 3.3% compared with the total number from the previous quarter. This small increase may be due to seasonal variation.

The proportion of S. aureus bacteraemias which were meticillin resistant during the quarter October to December 2012 was 13.7%. The 2011 figures for Europe, published in the Antimicrobial resistance surveillance in Europe 2011 report show that the proportion of S. aureus bacteraemias which were meticillin resistant was 16.7%.4

Funnel plot analysis was used to examine variations in NHS board S. aureus bacteraemia rates. No NHS boards were above the upper 95% confidence intervals in the S. aureus bacteraemia funnel plots. The funnel plots do not account for differences in the clinical activities performed in different NHS boards. Therefore, care must be taken in interpreting these graphs, particularly for the NWTC which is a small board providing specialist services.

The national S. aureus bacteraemia rate per 100 000 AOBDs during the period April 2005 to December 2012 showed a significant downward trend and this was estimated as a reduction of 7.5% per year (95% CI: 6.4% to 8.6%).

Acknowledgements

Health Protection Scotland is grateful to all of the microbiologists throughout Scotland who provided the S. aureus bacteraemia data for this report and helped in its preparation, staff at the Scottish MRSA Reference Laboratory and to the Information Services Division of National Services Scotland for providing the hospital activity data. Our thanks also go to Information Services Division of National Services Scotland for their statistical support.

References1 Health Protection Scotland. The Annual Surveillance of Healthcare Associated

Infections Report January - December 2011 [online]. Available: http://www.hps.scot.nhs.uk/haiic/sshaip/publicationsdetail.aspx?id=51462 [accessed 27 February 2012]. 2012.

2 Health Protection Scotland. Protocol for the Scottish Mandatory Surveillance Programme for Staphylococcus aureus bacteraemia [online]. Available: http://www.documents.hps.scot.nhs.uk/hai/sshaip/guidelines/s-aureus/s-aureus-bacteraemia-protocol-v5-2012-12.pdf [accessed 27 February 2012]. 2011.

3 Spiegelhalter D. Funnel plots for comparing institutional performance. Statistics in Medicine. 2005;24:1185-202.

4 European Centre for Disease Prevention and Control (ECDC). Antimicrobial resistance surveillance in Europe 2011 [online]. Available: http://ecdc.europa.eu/en/publications/Publications/Forms/ECDC_DispForm.aspx?ID=998 [accessed 27 February 2012]. 2011:1- 209

The last quarterly report on the surveillance of Staphylococcus aureus bacteraemia in Scotland was in Issue 13/02The next quarterly report on the surveillance of Staphylococcus aureus bacteraemia in Scotland will be in Issue 13/27

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Surveillance Report

Quarterly report on the surveillance of Clostridium difficile infection (CDI) in Scotland, October - December 2012

Prepared by: Health Protection Scotland

Executive Summary

• This report provides a summary of CDI data for October to December 2012 (Q4 2012) in Scotland. This includes data for CDI in patients aged ≥65 years and 15-64 years.

• In total, 313 new cases of CDI in patients aged ≥65 years were reported to Health Protection Scotland (HPS) during this quarter. The overall incidence rate for Scotland was 26.7 cases per 100 000 total occupied bed days. This is a 16% decrease from the previous quarter and is the lowest rate reported for this age group since the beginning of mandatory surveillance.

• In total, 120 new cases of CDI in patients aged 15-64 years were reported to HPS during this quarter. The overall incidence rate for Scotland was 34.4 cases per 100 000 acute occupied bed days. This is a 17% decrease from the previous quarter.

• The year on year trend analysis comparing 2011 to 2012 shows a non-statistically significant decrease in the overall incidence rate for patients aged ≥65 years of 2.0% (95% CI: -15.2% to 13.3%). In patients aged 15-64 years, there was a non-statistically significant decrease of 10.6% (95% CI: -24.7% to 6.1%).

• There remains scope for reduction of incidence rates in both age groups through continued local monitoring, appropriate prescribing, and maintenance of infection prevention and control measures. NHS boards are reminded to follow the national Guidance on Prevention and Control of CDI in Healthcare Settings in Scotland.

1. Introduction

Clostridium difficile infection (CDI) is an important healthcare associated infection and is a major cause of morbidity and mortality. Major risk factors for CDI include old age and previous use of antibiotics. Disease ranges from mild self-limiting diarrhoea to severe diarrhoea, pseudomembranous colitis, toxic megacolon and death.

In Scotland, mandatory surveillance of CDI was introduced in 2006 and initially focused on the incidence of CDI in patients aged ≥65 years (the age group most at risk). In April 2009, the programme was extended to include patients aged 15-64 years.

The programme is supported by a ribotyping service provided by the Scottish Salmonella, Shigella and Clostridium difficile Reference Laboratory (SSSCDRL). Mandatory surveillance of ribotypes falls into two categories: a) clinical surveillance: isolates associated with outbreaks and severe disease, and b) representative surveillance: isolates from a fixed proportion of all cases including mild, moderate and severe disease. Surveillance of severe cases/outbreaks began in November 2007, and representative surveillance in January 2009.

The national surveillance programme is retrospective (i.e., three months in arrears). It is important that NHS boards have their own local CDI surveillance systems to alert local teams to the need for possible action. This surveillance report does not replace local monitoring of CDI by NHS boards’ infection control teams.

2. Methods

Data sources and reporting

Full details of the data sources (including denominators, calculation of rates and statistical analyses) and the definitions

used to generate this report are published on the HPS website and may also be accessed from: http://www.documents.hps.scot.nhs.uk/hai/sshaip/publications/cdi/2012/methods-caveats-q4.pdf.

From January 2012, the scaling factor used in reporting the quarterly incidence rates has changed to ‘per 100 000 bed days’ instead of the previously used ‘per 1000 bed days’.

All previous published data can be accessed at: http://www.hps.scot.nhs.uk/haiic/sshaip/clostridiumdifficile.aspx?subjectid=79#ar.

The Protocol for the Scottish Surveillance Programme for Clostridium difficile Infection (version 3.0) is available from: http://www.hps.scot.nhs.uk/haiic/sshaip/guidelinedetail.aspx?id=40899.

The protocol for the Snapshot Programme (representative surveillance) is available from: http://www.hps.scot.nhs.uk/haiic/sshaip/guidelinedetail.aspx?id=46879.

Identification of outliers

Funnel plots are used to identify outliers. The NHS board level incidence rates are plotted on the funnel plots against the number of 100 000 bed days with the 95% confidence limits for the Scottish incidence rate. NHS board level incidence rates outside the 95% confidence limits are considered outliers.

Analysis of trends

Trend analysis of incidence rates is based upon the most recent two years of data.

Please note CDI rates in this report have been updated due to a subsequent revision of the national figures of hospital activity. Please go to http://www.hps.scot.nhs.uk/haiic/sshaip/publicationsdetail.aspx?id=50174 for the newest revised data.

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3. Results

3.1 Surveillance data

CDI incidence in patients aged >65 years

The total number of new cases identified in patients aged ≥65 years during Q4 2012 was 313 (in the previous quarter there were 369 cases). This is an overall incidence rate of 26.7 per 100 000 total occupied bed days (hereafter ‘total bed days’), a 16% decrease from the previous quarter (31.9 per 100 000 total bed days), and the lowest rate reported in this age group to date.

Individual incidence rates by NHS board for this quarter compared with the previous quarter are shown in Figure 1 (mainland NHS boards) and Figure 2 (island NHS boards and NHS National Waiting Times Centre (NWTC)). The separation of mainland from smaller NHS boards is to reflect the smaller denominators from the island NHS boards and NHS NWTC which can make a single graph difficult to interpret.

Incidence rates decreased substantially this quarter in NHS Ayrshire & Arran, NHS Borders, NHS Dumfries & Galloway, NHS Forth Valley, NHS Grampian and NHS Lothian. Only the decrease in NHS Dumfries & Galloway (from 51.6 per 100 000 total bed days in Q3 2012 to 6.8 per 100 000 total bed days this quarter) was statistically significant and the lowest rate reported for this NHS board to date (Figure 1). Incidence rates in the three island boards and NHS NWTC increased though overall case numbers were low (Figure 2).

FIGURE 1: Incidence rates of CDI per 100 000 total bed days in patients aged ≥65 years in 11 mainland NHS boards in Scotland

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NHS board

October 2012 to December 2012 October 2011 to September 2012

Number of cases Bed days

Incidence rate (per 100 000 bed

days)

Number of cases Bed days

Incidence rate (per 100 000 bed

days)

Ayrshire & Arran 31 88555 35.0 177 363404 48.7

Borders 9 28177 31.9 46 104456 44.0

Dumfries & Galloway 2 29461 6.8 43 135293 31.8

Fife 20 62870 31.8 75 256087 29.3

Forth Valley 5 63829 7.8 30 261081 11.5

Grampian 19 91645 20.7 97 365127 26.6

Greater Glasgow & Clyde 61 343306 17.8 306 1371916 22.3

Highland 9 47572 18.9 58 201950 28.7

Lanarkshire 47 116959 40.2 165 492990 33.5

Lothian 54 191407 28.2 263 757794 34.7

National Waiting Times Centre 1 7489 13.4 2 27405 7.3

Orkney 4 2324 172.1 7 9503 73.7

Shetland 1 2488 40.2 0 9916 0.0

Tayside 46 90162 51.0 136 381113 35.7

Western Isles 4 6365 62.8 6 28394 21.1

Scotland 313 1172609 26.7 1411 4766429 29.6

TABLE 1: CDI cases, bed days and incidence rates by NHS board in patients aged ≥65 years in the period October to December 2012 compared to the annual incidence rate for the year ending September 2012

Please note CDI rates in this report have been updated due to a subsequent revision of the national figures of hospital activity. Please go to http://www.hps.scot.nhs.uk/haiic/sshaip/publicationsdetail.aspx?id=50174 for the newest revised data.

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Figures 3 and 4 show that the rates per 100 000 population were in concordance with the incidence rates reported per 100 000 total bed days. The overall rate was 35.5 cases per 100 000 population (in the previous quarter the rate was 42.0 per 100 000 population). NHS NWTC, being an NHS Special Health Board and therefore not covering a specified population within Scotland, is not included in these.FIGURE 3: Incidence rates of CDI per 100 000 population in patients aged ≥65 years in 11 mainland NHS boards in Scotland

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Q3 2012Q4 2012

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Incidence rates for this quarter compared with the annual incidence rate for the last twelve months (October 2011 to September 2012) are given in Table 1. Most of the NHS boards have incidence rates for this quarter close to or below their corresponding annual rate. The majority of NHS boards have reported a decrease in annual incidence rates in 2012 compared to 2011, and all boards have shown a decline in incidence rates since the beginning of mandatory surveillance (see Section 3.3 and online appendices).

CDI incidence in patients aged 15-64 years

The total number of cases identified in younger patients during Q4 2012 was 120 (in the previous quarter there were 147 cases). The overall incidence rate for this quarter was 34.4 per 100 000 acute bed days, which is a 17% decrease from the previous quarter (41.6 per 100 000 acute bed days). There is wider variation among the NHS boards compared to incidence rates in patients aged ≥65 years (see Figures 9 and 10).

There were substantial decreases in the incidence rates in NHS Ayrshire & Arran, NHS Borders, NHS Forth Valley, NHS Grampian and NHS Greater Glasgow & Clyde. Substantial increases were observed in NHS Fife and NHS Lanarkshire. None of the changes were statistically significant (Figure 5).

Incidence rates decreased in NHS Orkney and increased in NHS Western Isles. Overall cases numbers were low. No cases were reported from NHS NWTC or NHS Shetland (Figure 6). FIGURE 5: Incidence rates of CDI per 100 000 acute bed days in patients aged 15-64 years in 11 mainland NHS boards in Scotland

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FIGURE 6: Incidence rates of CDI per 100 000 acute bed days in patients aged 15-64 years in the island NHS boards and NHS NWTC. NHS Shetland reported no cases between Q3 2012 and Q4 2012

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Figures 7 and 8 show that the rates per 100 000 population were in concordance with the incidence rates reported per 100 000 acute bed days. The overall rate was 3.4 cases per 100 000 population (in the previous quarter the rate was 4.2 per 100 000 population).

FIGURE 7: Incidence rates of CDI per 100 000 population in patients aged 15-64 years in 11 mainland NHS boards in Scotland

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Please note CDI rates in this report have been updated due to a subsequent revision of the national figures of hospital activity. Please go to http://www.hps.scot.nhs.uk/haiic/sshaip/publicationsdetail.aspx?id=50174 for the newest revised data.

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TABLE 2: CDI cases, bed days and incidence rates by NHS board in patients aged 15-64 years in the period October to December 2012 compared to the annual incidence rate for the year ending September 2012

NHS boardOctober 2012 to December 2012 October 2011 to September 2012

Number of cases Bed days

Incidence rate (per 100 000 bed

days)

Number of cases Bed days

Incidence rate (per 100 000 bed

days)Ayrshire & Arran 7 22498 31.1 49 96623 50.7Borders 1 4761 21.0 13 20838 62.4Dumfries & Galloway 7 6940 100.9 20 31578 63.3Fife 6 16498 36.4 23 63164 36.4Forth Valley 2 13210 15.1 12 53373 22.5Grampian 12 35087 34.2 68 130823 52.0Greater Glasgow & Clyde 25 109713 22.8 122 471295 25.9Highland 9 15595 57.7 35 69730 50.2Lanarkshire 10 33510 29.8 53 150325 35.3Lothian 26 55444 46.9 107 227926 46.9National Waiting Times Centre 0 5398 0.0 1 21808 4.6Orkney 0 277 0.0 3 2468 121.6Shetland 0 727 0.0 0 3154 0.0Tayside 14 27912 50.2 63 112690 55.9Western Isles 1 1101 90.8 5 5353 93.4Scotland 120 348671 34.4 574 1461148 39.3

FIGURE 8: Incidence rates of CDI per 100 000 population in patients aged 15-64 years in the island NHS boards. NHS Shetland reported no cases between Q3 2012 and Q4 2012

Orkney Western Isles

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Incidence rates for this quarter compared with the annual incidence rate for the last twelve months (October 2011 to September 2012) are given in Table 2. Most of the NHS boards have incidence rates for this quarter below or close to their corresponding annual rate (see also Section 3.3 and online appendices). NHS Dumfries & Galloway has a rate which is substantially above its corresponding annual rate.

3.2 Identification of outliers

Figures 9 and 10 show funnel plots of CDI incidence rates in patients ≥65 years and patients aged 15-64 years, respectively, for all NHS boards during this quarter. There were no NHS boards identified as having an incidence rate above the 95% confidence limits during this quarter in either age group.

FIGURE 9: Funnel plot of CDI incidence rates in patients aged ≥65 years for all NHS boards in Scotland, October to December 2012

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FIGURE 10: Funnel plot of CDI incidence rates in patients aged 15-64 years for all NHS boards in Scotland, October to December 2012. NHS Orkney, NHS Shetland and NHS NWTC overlap

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Key to NHS boardsAA Ayrshire & Arran FV Forth Valley LN Lanarkshire SH ShetlandBR Borders GGC Greater Glasgow & Clyde LO Lothian TY TaysideDG Dumfries & Galloway GR Grampian NWTC National Waiting Times Centre WI Western IslesFF Fife HG Highland OR Orkney

Please note CDI rates in this report have been updated due to a subsequent revision of the national figures of hospital activity. Please go to http://www.hps.scot.nhs.uk/haiic/sshaip/publicationsdetail.aspx?id=50174 for the newest revised data.

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3.3 Analysis of trends

The trends of CDI incidence rates covering the full surveillance period for both age groups are available for the individual NHS boards from: http://www.documents.hps.scot.nhs.uk/hai/sshaip/publications/cdi/2012/2012-q4-65plus-trend-by-board.pdf and http://www.documents.hps.scot.nhs.uk/hai/sshaip/publications/cdi/2012/2012-q4-15-64-trend-by-board.pdf.

Patients aged >65 years

Overall, the year on year analysis comparing 2011 and 2012 indicates a non-statistically significant decrease of 2.0% (95% CI: -15.2% to 13.3%). Figure 11 shows the overall incidence rates from Q4 2006 to Q4 2012. Incidence rates in 2011 and 2012 appear to be greater in Q2 and Q3 compared to Q1 and Q4, indicating seasonal variation.

Year on year analysis shows non-statistically significant decreases in NHS Ayrshire & Arran, NHS Dumfries & Galloway, NHS Forth Valley, NHS Greater Glasgow & Clyde, NHS Lanarkshire and NHS Lothian.

A statistically significant increase was reported from NHS Fife. The increases in NHS Borders, NHS Grampian, NHS Highland and NHS Tayside were non-statistically significant.

Patients aged 15-64 years

Overall, the year on year analysis comparing 2011 and 2012 indicates a non-statistically significant decrease of 10.6% (95% CI: -24.7% to 6.1%). Figure 12 shows the overall incidence rates from Q2 2009 to Q4 2012. As with patients aged ≥65 years above, incidence rates appear to be higher in Q2 and Q3 compared to Q1 and Q4.

Year on year analysis shows that there were statistically significant decreases in NHS Ayrshire & Arran and NHS Greater Glasgow & Clyde. Non-statistically significant decreases occurred in NHS Borders, NHS Grampian, NHS Lanarkshire and NHS Lothian.

Statistically significant increases were reported in NHS Forth Valley and NHS Highland. The increases in NHS Dumfries & Galloway, NHS Fife and NHS Tayside were non-statistically significant.

Trend analyses in either age group were not carried out for NHS Orkney, NHS Shetland, NHS Western Isles and NHS NWTC due to their reporting no or very few cases over the period.FIGURE 11: Overall quarterly CDI incidence rates for Scotland (per 100 000 total bed days) in patients ≥65 years for the period October 2006 to December 2012

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FIGURE 12: Overall quarterly CDI incidence rates for Scotland (per 100 000 acute bed days) in patients aged 15-64 years for the period April 2009 to December 2012

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3.4 Typing and susceptibility data

Ribotypes 078 and 002 were the two most common ribotypes reported from severe cases and/or outbreaks (both at 16%, out of a total of 137) and from isolates typed from a representative sample of all CDI cases (17% and 15%, respectively, out of a total of 117). This is the first decrease in the prevalence of 078 (from 27% in the previous quarter) following four consecutive quarterly increases.

The proportions of types 106 (1% and 3% from severe cases and/or outbreaks and a representative sample, respectively), 001 (both 3%) and 027 (2% and 1%, respectively) remain low compared to previous years.

The other major ribotypes (prevalence >3%) in Scotland comprise 002, 005, 014, 015, 020, 023 and 026 (ribotype 026 was previously considered a rare type).

All isolates were susceptible to vancomycin and metronidazole.

4. DiscussionIncidence rates have decreased in both age groups this quarter. The decrease in patients aged ≥65 years was statistically significant. This is the first decrease since Q1 2012 as well as the lowest rate reported in this age group since the beginning of mandatory surveillance. Variation in the incidence rates reported in patients aged ≥65 years has been reduced among the NHS boards, which has been one of the public health objectives for the surveillance programme. Wider variation in patients aged 15-64 years remains.

Some NHS boards (in both age groups) have marked quarterly fluctuations. This may be associated with underlying antibiotic prescribing issues and/or reflect variation in the proportion of CDI cases acquired in the community. HPS is introducing sentinel community CDI surveillance during 2013 to investigate this further.

The year on year trend analysis also shows a decrease in incidence rates overall for Scotland in both age groups. The majority of NHS boards have reported decreases in their incidence rates between 2011 and 2012, which follows large declines in incidence rates since the beginning of mandatory surveillance. However, some NHS boards reported significant increases compared to the previous year, which is a reminder that there is scope for further reductions in CDI incidence rates within Scotland.

Seasonal variation in both age groups is apparent with higher incidence rates in Q2 and Q3 compared to Q1 and Q4. This is under further investigation.

Please note CDI rates in this report have been updated due to a subsequent revision of the national figures of hospital activity. Please go to http://www.hps.scot.nhs.uk/haiic/sshaip/publicationsdetail.aspx?id=50174 for the newest revised data.

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Ribotype 078 has decreased this quarter but remains the most common ribotype in Scotland followed by ribotype 002. Ribotype 078 has become much more prevalent during 2012 (for reasons that are unclear) whereas ribotype 002 has been the most common ribotype after 106, 001 and 027 in previous years. There are no specific infection prevention and control measures for individual ribotypes; current national guidance should be followed.

The Scottish Microbiology and Virology Network, in collaboration with the Scottish C. difficile Reference Laboratory and HPS, published a revised Recommended protocol for testing for Clostridium difficile and subsequent culture in December 2012. The protocol has been revised following new evidence that has evaluated diagnostic algorithms for the diagnosis of CDI. The protocol and accompanying FAQs are available from: http://www.hps.scot.nhs.uk/haiic/sshaip/guidelinedetail.aspx?id=53536 and http://www.hps.scot.nhs.uk/haiic/sshaip/guidelinedetail.aspx?id=53537.

Appropriate local monitoring, antimicrobial prescribing and implementation of infection prevention and control at both hospital and community levels are key to maintaining and reducing CDI rates. NHS boards are reminded to follow the national Guidance on Prevention and Control of CDI in Healthcare Settings in Scotland, which includes details on SICPs and TBPs. The Guidance is available from: http://www.hps.scot.nhs.uk/haiic/sshaip/guidelinedetail.aspx?id=42640.

Note:

Caveats for this report may be accessed from: http://www.documents.hps.scot.nhs.uk/hai/sshaip/publications/cdi/2012/methods-caveats-q4.pdf.

Individual CDI rates and denominator data published since October 2006 for each NHS board and overall for Scotland can be accessed from an online appendix: http://www.documents.hps.scot.nhs.uk/hai/sshaip/publications/cdi/2012/2012-q4-appendix-board-bed-days-rates.xls.

Acknowledgement

We would like to thank all the microbiologists and biomedical scientists who have provided and reviewed data for the CDI surveillance programme and the Scottish C. difficile reference service for providing ribotyping data. Information Services Division of the NHS in Scotland is thanked for its statistical support for this report and for providing the hospital activity denominator data. Our thanks also for the continuing hard work of the infection control and antimicrobial management teams in helping to reduce the burden of CDI; they are to be commended for their efforts.

The last quarterly report on the surveillance of Clostridium difficile infection in Scotland was in Issue 13/02The next quarterly report on the surveillance of Clostridium difficile infection in Scotland will be in Issue 13/27

Please note CDI rates in this report have been updated due to a subsequent revision of the national figures of hospital activity. Please go to http://www.hps.scot.nhs.uk/haiic/sshaip/publicationsdetail.aspx?id=50174 for the newest revised data.

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Notifiable diseases

Part 2 (Notifiable Diseases, Organisms and Health Risk States) of the Public Health etc.(Scotland) Act came into effect on 1 January 2010 and sets out new duties for registered medical practitioners, NHS boards and directors of diagnostic laboratories. GP practices should familiarise themselves with the Scottish Government guidance on the new notification requirements at: http://www.scotland.gov.uk/Topics/Health/Policy/Public-Health-Act.

Registered medical practitioners report notifiable diseases based on ‘clinical suspicion’. As such, notifications may not be subject to laboratory report confirmation. The published figures will record therefore how many diseases have been clinically suspected.

Patient notifications can, however, be reclassified. When, for example, a suspected (and notified) tuberculosis case is subsequently reported as negative by a laboratory (and found not to be a health protection risk) it would subsequently be removed from the disease totals.

Diseases to be notified by registered medical practitioners with effect from 1 January 2010:

It is recommended that those diseases above marked with an * require urgent notification, i.e. within the same working day.

Note 1: Escherichia coli O157Clinical suspicion should be aroused by (i) likely infectious bloody diarrhoea or (ii) acute onset non-bloody diarrhoea with a biologically plausible exposure and no alternative explanation. Examples of biologically plausible exposures include:

• contact with farm animals, their faeces or environment;

• drinking privately supplied or raw water;

• eating foods such as undercooked burgers or unpasteurised dairy products;

• contact with a confirmed or suspected case of VTEC infection.

Further guidance is available at: http://www.hps.scot.nhs.uk/giz/e.coli0157.aspx.

Where a case is notified as HUS (Haemolytic Uraemic Syndrome) it should NOT also be notified as ‘Clinical syndrome due to E. coli O157 infection’.

Note 2: TuberculosisFor the purposes of notification, respiratory TB or non-respiratory TB should be taken to have the same meanings as the World Health Organisation definitions of pulmonary TB and non-pulmonary TB respectively:

Pulmonary TB is tuberculosis of the lung parenchyma and/or the tracheobronchial tree.

Non-pulmonary TB is tuberculosis of any other site.

Where tuberculosis is clinically diagnosed in both pulmonary and non-pulmonary sites, this should be treated as pulmonary TB.

Registered medical practitioners have been advised to contact their local NHS Board Health Protection Team for advice should they have any doubts about the diagnosis of suspected cases.

Non-notifiable diseasesRegistered medical practitioners are no longer required to notify the diseases listed below.

• Bacillary dysentery • Chickenpox • Food poisoning • Scarlet fever • Viral hepatitis

These diseases are now covered by a list of notifiable organisms details of which will be reported by laboratories to health protection teams.

Notifiable Diseases which come into effect on 1 January 2010 *Anthrax *Meningococcal disease *Severe Acute Respiratory Syndrome (SARS) *Botulism Mumps *Smallpox Brucellosis *Necrotising fasciitis Tetanus

*Cholera *Paratyphoid Tuberculosis (respiratory or non-respiratory) (see Note 2)

*Clinical syndrome due to E. coli O157 infection (see note 1) *Pertussis (Whooping Cough) *Tularemia

*Diphtheria *Plague *Typhoid *Haemolytic Uraemic Syndrome (HUS) *Poliomyelitis *Viral haemorrhagic fevers*Haemophilus influenzae Type b (Hib) *Rabies *West Nile fever*Measles Rubella Yellow Fever

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Statutory Notification of Infectious DiseasesWeek ended 22 March 2013

A National Statistics release

Infectious Disease Current week

Previous week

Current week last

year

Total from first week of year

2012 2013Anthrax - 1 - - 1

Botulism - - - - -Brucellosis - - - - -Cholera - - - - 1Clinical Syndrome E. coli O157 - - - 1 -Diphtheria - - - - -Haemolytic Uraemic Syndrome (HUS) - 1 - - 1Haemophilus Influenzae Type B (Hib) - - - - -Measles 3 2 - 18 29Meningococcal Infection - - 1 24 19Mumps 7 8 24 217 128Necrotizing Fasciitis - - - - 1Paratyphoid Fever - - - - -Pertussis 30 15 23 70 471Plague - - - - -Poliomyelitis - - - - -Rabies - - - - -Rubella - - 3 12 5Severe Acute Respiratory Syndrome (SARS) - - - - -Smallpox - - - - -Tetanus - - - - -Tuberculosis: Respiratory 1 3 6 46 47Tuberculosis: Non-respiratory - 2 1 26 30Tularemia - - - - -Typhoid Fever - - - - 3Viral Haemorrhagic Fevers - - - - -West Nile Fever - - - - -Yellow Fever - - - - -TOTAL 41 32 58 414 736

Amendments: Add 1 Pertussis (1 x wk 11); 2 Tuberculosis : respiratory (1 x wk 6, 1 x wk 8); 3 Tuberculosis: non-respiratory (1 x wk 9, 2 x wk 11) Delete 2 Haemophilus influenzae Type B (Hb) (2 x wk 11); 1 Pertussis (1 x wk 10)

Source: Health Protection Scotland, NHS National Services Scotland

NHS BOARD ABBREVIATIONSAA Ayrshire & Arran GGC Greater Glasgow & Clyde LN Lanarkshire SH Shetland TY TaysideBR Borders FF Fife GR Grampian LO Lothian WI Western IslesDG Dumfries & Galloway FV Forth Valley HG Highland OR Orkney