ANC surveillance research

Yusufu Kumogola, Emma Slaymaker,

Raphael Isingo, Julius Mngara, Basia Zaba,

John Changalucha and Mark Urassa

TAZAMA / NACP seminar,

Dar-es-Salaam, September 19th 2008

Structure of presentation

1. “Added value” of surveillance research: topics investigated, methods and clinics used

2. Specific aims and results from rounds 1 & 2

3. Specific aims and results from round 3

4. Plans for round 4

5. Policy implications of findings and suggestions for NACP surveillance

Overview of surveillance research

GENERAL AIMS• To put the Kisesa sero-survey findings into a wider context• To generate HIV surveillance data to complement NACP activities• To discover biases affecting national ANC surveillance• To evaluate and extend service availability in ANC • To explore possibilities of adding extra data to national surveillance

SPECIAL TOPICS• 2000 & 2002: establish baseline and investigate sexual behaviour• 2006: travel to clinics and type of service provided• 2008: use of family planning in the context of PMTCT

How the ANC clinics were chosen

• The 2000/02 studies used a “convenience sample” 11 ANC clinics in Magu district and eastern part of Mwanza city which already did routine syphilis tests or in which it was feasible to introduce syphilis testing

• The 2006 study added all other ANC clinics in Magu district and eastern Mwanza that had started providing syphilis tests (2 clinics) or VCT (1 clinic)

• The 2006 study also added 11 other clinics in which lab tests were not available, but which were located within a 20 km radius of clinics providing HIV or syphilis tests – women in these clinics were interviewed but not tested

• The 2008 study is using all the clinics that were able to provide lab tests in the previous rounds

Our basic questionnaire

Background: date of birth, residence, education, parity, date of last birth, survival of last born

Clinic choice: previous clinic attendance, transport, reason for using this clinic

Father of the baby: is she married to father, his age and residence, does he have other wives / girlfriends

Sexual behaviour: age at first sex, age at first marriage, other partners apart from father of the baby

Test history: ever had VCT or syphilis test before

Use stickers to link data and specimens

Questionnaire completed in clinic

RPR test done in clinic

HIV test done at NIMR

no names used !

Aims of 2000/02 survey

• Establish HIV infection levels and trends in urban, roadside and remote clinics

• Measure extent of co-infection with syphilis by type of clinic

• Describe patterns of sexual behaviour in young pregnant women

• Identify behavioural risk factors for HIV infection

Findings from 2000/02 rounds

HIV prevalence was higher in rural roadside clinics and Mwanza city (10% to 13%) than in remote rural clinics and Magu town (6% to 9%)

But syphilis was more prevalent in remote rural and roadside clinics (15% to 21%) compared to city and town clinics (9% to 10%): suggesting higher use of antibiotics in urban areas?

HIV prevalence in ANC women by years of sexual activity before and after marriage

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0 1 2 3 4 5 6 7 8

years of exposure

HIV

pre

val

ence

pre-marital

post marriage

Women who spent more years sexually active before getting married were at higher risk of HIV infection.

Simple questions about age at first sex and age at first marriage can provide useful data for community advocacy

Aims of 2006 study

1. To measure the proportion of women accepting VCT in ante-natal clinics that offered the service

2. To find out which kind of women received VCT during pregnancy

3. To identify clinics with high unmet need for VCT services for pregnant women

4. To establish the extent of travel to non-local ANC clinics in this population.

5. To assess whether travel to non-local clinics affects HIV prevalence estimates

Location of clinics used in 2006 ANC surveillance study and other health facilities in Mwanza region

Use of VCT• 88% of women attending VCT clinics accepted counselling• About 70% of women attending clinics that did not provide

VCT were attending their nearest clinic; 40% of those attending VCT clinics were attending nearest clinic

• Important predictors of VCT use (after allowing for clinic location) were: – urban residence (AOR 8.6, CI 7.2 – 10.2)– primary or higher education (AOR 1.8, CI 1.4 – 2.4)– never married (AOR 1.5, CI 1.1 – 2.0)– age group 20-29 (AOR 1.2, CI 1.0 – 1.4)

Results of surveillance: HIV prevalence by clinic location

0

2

4

6

8

10

12

14

16

18

20

2000 2002 2004 2006

Surveillance year

HIV

pre

va

len

ce

, %

Urban Roadside Rural

HIV prevalence by PMTCT provision

0

2

4

6

8

10

12

14

16

18

20

2000 2002 2004 2006

Surveillance year

HIV

pre

va

len

ce

, %

Started PMTCT between 2002 and 2006 Not yet started PMTCT

050

01,

000

1,50

02,

000

2,50

0

Num

ber

atte

ndin

g th

is t

ype

of c

linic

Urban Roadside Rural

VCT AnonNone VCT AnonNone VCT AnonNone

Type and location of nearest clinic

Type of clinic attendedby nearest clinic type and location

None

Anon

VCT

Clinicattended

HIV prevalence in women whose nearest clinic provided syphilis testing but not VCT

0.00

0.05

0.10

0.15

0.20

All In study area Out of study area

Type of clinic attended

HIV

pre

va

len

ce

VCT Anon

050

01,

000

1,50

02,

000

2,50

0

Num

ber

stat

ing

mai

n re

ason

further nearest

VCT Anon no test VCT Anon no test

Reasons for clinic attendanceby clinic type and proximity

nonereferred

personalHIV testSTD test

goodaccessclose

Main reason

How far do women travel?  

0 5 10 15

Average distance travelled (kms)

Rural

Roadside

Urban

Anon

VCT

Anon

VCT

Anon

VCT

Distance travelled by area of residence,type of clinic attended and HIV status

Negative

Positive

HIVstatus

Aims of 2008 ANC survey & follow-up

• Describe Family Planning (FP) use before pregnancy and in post partum interval

• Assess if prior FP use differs by HIV status • Assess if post partum FP use differs by HIV

status in women who had VCT• Test the efficacy of added FP counselling added

to VCT and tailored to status• Evaluate uptake of PMTCT by infected women

who had VCT

NACP surveillance advice

• There is no evidence of new bias introduction into surveillance estimates of HIV prevalence, due to clinic choice by pregnant women

• To maintain bias-free surveillance in PMTCT clinic, do not include tests on women who have been referred from other clinics

• Questions on residence will help map HIV prevalence with less dependence on clinic location

• Questions on re-marriage, survival of last born child, and length of birth interval are easy to ask in all ANC and can be used to identify pregnant women who are at high risk of HIV infection

Policy implications

• High prevalence of syphilis in rural areas suggests screening and treatment is an important priority: treatment is cheap and impact on infant mortality is high

• Extending syphilis testing to rural areas also provides more opportunities for anonymous HIV surveillance

• Volume of HIV positive tests per week in clinics doing only anonymous testing is a good guide for prioritising VCT roll-out

• Women who are identified as high risk in ANC clinics that do not offer VCT should be referred for PMTCT