Polly Clayden, HIV i-Base
A large proportion of pregnant and breastfeeding women with high viral load were undiagnosed in a study conducted in Kenya, Malawi and South Africa. David Mamen from Médecins sans Frontières presented these findings at CROI 2015.
Dr Mamen pointed out that although maternal viral load is a strong predictor of vertical transmission, few studies have investigated population viral load and cascade of care in pregnant/breast feeding women.
The study was a secondary analysis of three large population surveys of participants aged 15-59 in randomly selected households in Ndhiwa (Kenya), Chiradzulu (Malawi) and Mbolongwane/Eshowe (South Africa). The surveys were conducted between September 2012 and November 2013.
There were 12,461 eligible women and 11,550 (92 .7%) consented to be included in the study. Women answered a questionnaire, which included questions on HIV testing, pregnancy, birth, breastfeeding and antenatal attendance. They were then tested for HIV with a rapid test. HIV positive women had their status confirmed by ELISA and negative women by NAT. Positive women were given CD4 and viral load testing. The investigators also measured incidence using recent infection assays.
At the time of the study, Kenya was implementing WHO PMTCT Option A, Malawi Option B+ and South Africa Option B.
The proportion of women who were pregnant or breastfeeding was higher in Kenya, 37.8% (1413/3760) and Malawi, 33.8%, (1444/4275) than in South Africa, 12 .5% (439/3515). Among them, HIV prevalence ranged from 13.4% in Malawi to 22.2% in Kenya and 23 .0% in South Africa. Dr Maman added that when they looked at women aged 15-29 years, this proportion reached 50% in Kenya and Malawi.
The median age of women across all sites was about 25 years of age. HIV prevalence was higher in Kenya (22.2%) and South Africa (23.0%), than Malawi (13.4%).
A high proportion of women attended at least one antenatal clinic: 94.0%, 98.8% and 96.4% in Kenya, Malawi and South Africa, respectively. Fewer women attended at least three antenatal clinics: 75.5%, 86.1% and 73.1%, respectively. Most received an HIV test at their antenatal visit: 85.0%, 89.8% and 93.2%, respectively.
Although the proportion of women tested for HIV was similar across sites, the proportion diagnosed varied greatly from above 80% in Malawi to just over 50% in Kenya. In sites where Option B and B+ were implemented there was less loss at all stages of the cascade of care: diagnosis, link to care, in care, on ART and viral load <1000 copies/mL. The proportion of pregnant or breastfeeding women with viral load <1000 copies/mL was much higher in Malawi (72.3%)and South Africa (63.4%), than Kenya (27.3%). But, even in Malawi, 12% of pregnant or breastfeeding women had viral load >100,000 copies/mL.
Of the breastfeeding women with viral load >1,000 copies/mL (n=220), 58 .6% were undiagnosed at the time of the survey, despite the majority (37.8%) testing negative at a routine antenatal visit. The proportion was similar across sites
Overall 4.1% of breastfeeding women were infected during pregnancy or breastfeeding. The proportion was higher in Kenya (7.4%) than in South Africa (4.9%) and Malawi (2.1%).
HIV incidence among breastfeeding women aged 15-29 years, using incidence (recent infection) assays was: 3.8, 0.9 and 3.2 per 100 person years in Kenya, Malawi and South Africa, respectively.
The study investigators recommended implementing Option B+ and following the WHO guidelines as far as possible. Dr Maman added that Option B+ might not be enough and that a successful programme must also reduce HIV incidence among young women though strategies such as treatment as prevention and PrEP. “A bolder approach to PMTCT is required”, he said.
He called for programmes to: “Diagnose women and infants where they are”. HIV tests need to be repeated in women at antenatal visits and delivery. Infants need to be tested whenever they visit a health facility not just within PMTCT programmes.
David Maman D et al. Most breastfeeding women with high viral load are still undiagnosed in Sub-Saharan Africa. CROI 2015. Seattle, Washington. 23-26 February, 2015. Oral abstract 32.