the present situation the strategies the vaccination the controversy

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The Present Situation The Strategies The Vaccination The Controversy The Fight Against Measles

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Page 1: The Present Situation The Strategies The Vaccination The Controversy

The Present Situation

The Strategies

The Vaccination

The Controversy

The Fight Against Measles

Page 2: The Present Situation The Strategies The Vaccination The Controversy

• About 20 million cases each year around the globe.

2011

UK- 804 cases

Ireland – 173 cases

Europe - more than 26,000 cases

8 deaths

24 cases measles encephalitis

• Africa and Asia , remains one of leading causes of death in children. – WHO - 164,000 people died from measles in 2008, most younger than 5 years old.

Recent Outbreaks

Page 3: The Present Situation The Strategies The Vaccination The Controversy

•Increase in measles cases and deaths in recent months

•Prevalent in famine and drought areas

•Unvaccinated children forced to live in cramped refugee camps

•Somalia – 24%of 1yr olds immunized in country

Recent Outbreaks (2)

Page 4: The Present Situation The Strategies The Vaccination The Controversy

Increase in US cases

•over 92% population vaccinated•Dropped due to importation of disease from WHO European Regions and South East Asian regions.•33 countries in WHO European Region have increased measles cases

Eradication

Page 5: The Present Situation The Strategies The Vaccination The Controversy
Page 6: The Present Situation The Strategies The Vaccination The Controversy

MMR Vaccine

Developed in 1960s by Maurice Hilleman

3 live attenuated viruses

First dose ~1 year, second ~5 years.

Before vaccination, measles “as inevitable as death and taxes”.

Now contracted by <1% of individuals under 30 in countries with routine childhood vaccination

Prevents illness, disability, death.

Page 7: The Present Situation The Strategies The Vaccination The Controversy

WHO Strategy 1994 - 2004

Aim: Vaccinate >90% in all districts

All children to get second dose

71% of targeted children in 1999 -> 76% in 2004

Sub-Saharan Africa – 49% -> 65%

South Asia – 54% -> 61%

2004 – 168 counties (88%) offered second round

Page 8: The Present Situation The Strategies The Vaccination The Controversy

MMR in Ireland

First dose at 12 months

Second dose (not booster) at 4-5 years

Through school/HSE or GP

Recent outbreaks of measles and mumps due to missed second dose

Page 9: The Present Situation The Strategies The Vaccination The Controversy

1985 - Monocomponent measles vaccine introduced- 10,000 cases in that year reduced to 201 in 1987

1988- combined MMR introduced -12-15months

1992- Second dose recommended- 10-15 years

1999- Age of second dose reduced to 4-5 years

Childhood vaccination Schedule for children born after 1st July 2008- Free From the Department of Health, HSE• 12months from GP

• 4-5 yrs from GP or in School

• Primary School Immunisation Programme

Vaccination Strategy- Ireland

Page 10: The Present Situation The Strategies The Vaccination The Controversy

Outbreak in 1993- affected 4,000 people

2000- 1,600 cases resulted in 3 deaths

From 2001 to 2006 – 1,562 cases • Rapid spread during these outbreaks due to:• Incomplete vaccination coverage

• Susceptible pool of older unvaccinated children

Today- 221cases reported in 2011, so far (411 in 2010)• 85% occurred in North Dublin City

90% of children have received 1st dose by 24months

Page 11: The Present Situation The Strategies The Vaccination The Controversy

Global mortality reduced by 78% , from estimated 733 000 deaths in 2000 to an estimated 164 000 deaths in 2008-78%

The WHO region of America has

sustained elimination since 2002

The WHO has set a target of

elimation of measles in

remaining 4 out of 5

WHO regions by 2020.• This can only be achieved by

Increasing routine immunization coverage• improving surveillance systems• political and financial commitment

W.H.O-Measles Eradication

Page 12: The Present Situation The Strategies The Vaccination The Controversy

• There are two treatments to protect against measles:

• MMR: measles, mumps and rubella vaccine.

• MMRV: measles, mumps, rubella, and varicella vaccine.

Vaccination

Page 13: The Present Situation The Strategies The Vaccination The Controversy

• From nucleotide tests all vaccines were shown to be similar.

• At present the MMR vaccine has a 95% efficiency.

• First virus was obtained from David Edmonston in 1954.

• The virus strain was grown in chick embryos.

• Made the virus more suited to chicks than humans

• Similar attenuated vaccines around this time were developed.

Development

Page 14: The Present Situation The Strategies The Vaccination The Controversy

• Control: reduce incidence of disease. Due to 95% efficiency a two dose strategy is need to prevent an accumulation of susceptible individuals.

• In 2010, about 85% of the world's children received one dose of measles vaccine by their first birthday through routine health services – up from 72% in 2000. Two doses of the vaccine are recommended to ensure immunity, as about 15% of vaccinated children fail to develop immunity from the first dose.

WHO: Eradiation PolicyControl

Outbreak Prevention

Eradication

Page 15: The Present Situation The Strategies The Vaccination The Controversy

Children should be vaccinated with the MMR vaccine 12 to 15 months after birth and should receive a second dose at 4-5 year usually before the child enters school.

Before the vaccination programme was implemented in USA, between 3 to 4 million people were infected each year, with 400 to 500 dying

Measles is a highly contagious virus and was estimated there was 242,000 Measles deaths which equals 27 deaths every hour.

Measles Vaccine

Page 16: The Present Situation The Strategies The Vaccination The Controversy

• The vaccine like many vaccines can cause allergic reactions, most people however do not have any problems with it.

• Mild problems: fever (1 in 6 doses), mild rash ( 1 in 20) or rare swelling of glands.

• Moderate problems: seizure (1 in 3,000 doses), temporary pain in joints ( 1 in 4 teenage and adult women) and temporary low platelet counts which can lead to a bleeding disorder ( 1 in 30,000 doses).

• Sever problems: 1 in 1 million: deafness, long-term seizures or comas and permanent brain damage.

MMR Vaccine Risks

Page 17: The Present Situation The Strategies The Vaccination The Controversy

• Has a fever

• Is taking steroids

• Has had another live attenuated vaccine in the last three days

• Is receiving chemotherapy/radiotherapy

• Has a compromised immune system

Less safe if recipient...

Page 18: The Present Situation The Strategies The Vaccination The Controversy

Developing Countries Immunodeficiency

Individuals with low immune responses can’t handle certain vaccines due to the presence of attenuated or live virus.

• Presence of maternal antibodies during first 9 months of life reduces efficiency of immunization.

• Measles virus infects children by the respiratory tracts and little of the maternal antibodies will be transduced onto mucosal surfaces

Problems with Vaccine

Page 19: The Present Situation The Strategies The Vaccination The Controversy

Aerosol delivery and high titre vaccinations to overcome problems in vaccinating young infants.

1. Recombinant virus

2. Immune-stimulating complexes

3. DNA vaccination

Advancements

Page 20: The Present Situation The Strategies The Vaccination The Controversy

Controversy:Wakefield et al. 1998

Page 21: The Present Situation The Strategies The Vaccination The Controversy

• 12 Children with Gastrointestinal symptoms, lost acquired skills including communication

• In 8 children, parents and/or physicians linked onset of behavioural problems with MMR

• Main cause of public concern

Wakefield et al. 1998

Page 22: The Present Situation The Strategies The Vaccination The Controversy

• Wakefield: “I cannot support the continued use of these vaccines in combination…”

• Public uproar & slump in MMR vaccinations

• Brian Deer Sunday Times investigation 2003-2011

• Prof. John O’ Leary slander

Media Coverage

Page 23: The Present Situation The Strategies The Vaccination The Controversy

• Hornig et al. 2008 replications

• Wakefield foul play

Evidence against autism link & aftermath of investigation

Page 24: The Present Situation The Strategies The Vaccination The Controversy

Referenceshttp://www.immunisation.ie/en/Downloads/NIACGuidelines/PDFFile_15482_en.pdf

http://www.irishhealth.com/article.html?id=780

http://www.immunisation.ie/en/Downloads/PDFFile_15371_en.pdf

http://www.who.int/immunization_monitoring/diseases/measlesreportedcasesbycountry.pdf

http://www.immunisation.ie/en/ChildhoodImmunisation/PrimaryImmunisationSchedule/

http://apps.who.int/gb/ebwha/pdf_files/WHA63/A63_18-en.pdf

http://www.who.int/immunization/newsroom/news_wha_2010_measles_eradication/en/index.html

www.braindeer.com

http://www.who.int/mediacentre/factsheets/fs286/en/

http://www.cdc.gov/vaccines/vpd-vac/measles/default.htm

http://www.immunisation.ie/en/ChildhoodImmunisation/VaccinePreventableDiseases/MMR/

J. Wakefield, S. H. Murch, A. Anthony, J. Linnell, D. M. Casson, M. Malik, M. Berelowitz, A. P. Dhillon, M. A. Thomson (1998). Ileal-lymphoid-nodular hyperplasia, non-specific colitis, and pervasive developmental disorder in children.

T. F. Wild (1999) Measles vaccines, new developments and immunization strategies. Vaccine 17; 1726-1729.