Zimbabwe Approaching Virtual Elimination of Mother-to-Child Transmission of HIV Following Implementation of Option A

Raluca Buzdugan, Sandra I McCoy, Constancia Watadzaushe, Mi-Suk Kang Dufour, Maya Petersen, Jeffrey Dirawo, Angela Mushavi, Hilda Angela Mujuru, Agnes Mahomva, Barbara Engelsmann, Hakobyan

Anna, Mugurungi Owen, Frances M Cowan, Nancy S Padian

PMTCT Effectiveness

• WHO guidelines for PMTCT in developing countries:–2010: Option A, B

–2013: Option B+, B

• Important to assess the population-level effectiveness of the WHO guidelines

PMTCT in Zimbabwe

• 16% HIV prevalence in pregnant women (2012 sentinel data)

• 9,000 HIV infant infections in 2013

• Option A rolled out in Aug-Dec 2011

– 1344 of the existing 1,560 health facilities

– point-of-care CD4 testing machines

– community mobilization

• Option B+ started in Nov 2013

Impact Evaluation of Option A in Zimbabwe

• Serial cross-sectional community-based serosurveys

• Pre-post design with the facility catchment area as unit of analysis:– Baseline – 2012,

Endline - 2014

1 2

3

4

5

1. Mashonaland West, 2. Mashonaland Central3. Harare, 4. Matabeleland South, 5. Manicaland

Methods

SAMPLINGSTRATEGY

DATA COLLECTION METHODS

OUTCOMESMEASURED

157 health facilities randomly

selected from 5 of Zimbabwe’s 10 provinces

Identified all eligible infants

living in the catchment areas

of these facilities (using a

combination of methods)

Selected a pre-determined

fraction of all eligible mother-infant pairs and invited them to participate in

the survey

9,087 mother-infant pairs at

baseline (2012)

10,646 mother-infant pairs at endline (2014)

- Facility questionnaire,

head nurse

- Questionnaire with mothers/ caregivers- Blood samples of living infants & mothers

- Verbal autopsies of deceased mothers & infants

STAGE I STAGE II

Time of Option A rollout at facility-level

- HIV free infant survival at 9-18 months - MTCT rate at 9-18 months

Methods

• Eligible women were ≥16 years old and biological mothers of infants (alive or deceased) born 9-18 months prior.

• The impact analysis was limited to 113 catchment areas unexposed to Option A activities at baseline according to facility records.

Methods

• HIV-free infant survival = proportion of infants born to HIV-infected mothers who were alive and HIV-uninfected at 9-18 months of age

• MTCT = proportion of infants born to HIV-infected mothers who were HIV-infected at 9-18 months

• We estimated the HIV-free infant survival and MTCT rate in each catchment area and compared the 2012 and 2014 estimates using a paired t-test.

Study Enrolment2012 survey 2014 survey

Mother-infant pairs recruited 9,087 10,646Overall response rate 98.9% 99%

Mother-infant pairs with alive infants

9,019 10,625

Mother-infant pairs with viable maternal blood specimens

8,568 9,826

Questionnaires completed 9,018 10,637

Individual-level analyses

89

90

91

92

93

94

90.9

93.3

HIV

-fre

e in

fan

t su

rviv

al

(%)

2012 survey(n=1065)

2014 survey(n=1316)

Individual-level analyses

4

5

6

7

8

9

10

8.8

6.7

Mot

her

to

chil

d H

IV

tran

smis

sion

(%

)

2012 survey(n=1062)

2014 survey(n=1316)

Option A ImpactIn the 132 catchment areas where Option A was implemented after infants surveyed in 2012 were born (“catchment areas unexposed to Option A”): • 5.5 percentage point (95% CI: 2.6, 8.5) mean

increase in HIV-free infant survival (from 89.6% in 2012, p<0.001)

• 5.2 percentage point (95% CI: 2.2, 8.2) mean decrease in MTCT (from 10.0% in 2012, p<0.001)

since the rollout of Option A

# of HIV+ infants and MTCT rate in 156 CAs

Definition and distribution of health facility catchment area priority levels

Catchment Area Priority Level

Definition* N (%)

High ≥3 HIV+ infants 9-18 months of age and MTCT ≥10%

18 (11%)

Medium 1-2 HIV+ infants 9-18 months of age or 0 ≤ MTCT <10%

33 (21%)

Low No (0) HIV+ infants 9-18 months of age and MTCT = 0%

106 (68%)

Self-reported uptake of maternal ARV by CA priority level, Zimbabwe, 2014.

Comparing 2012 and 2014

Limitations

• Data were cross-sectional• Data are not representative of all regions

in Zimbabwe• Many mothers were still breastfeeding at the

time of survey (71% in 2012, 78% in 2014)• Infant deaths may have been underreported• Quasi experimental design

Conclusions

• Zimbabwe approaching virtual elimination of MTCT

• Substantial and statistically significant increase in HIV-free infant survival and decrease in MTCT at 9-18 months after Option A implementation

• Our community-based surveys included women who did not access health services

Acknowledgements

Ministry of Health and Child Care

EGPAF Zimbabwe• Reuben Musarandega

Funders: Children’s Investment Fund Foundation (CIFF) & the National Institutes of Heath.

UC Berkeley• Tyler Martz

CeSHHAR Zimbabwe• Survey team

Study participants