Prevention of Mother to Child Transmission of HIV

Describe the magnitude of the problem Session Objectives By the end of this session participants would be able to: Describe the magnitude of the problem and its impact; Describe the routes, rates and risks of HIV transmission from mother to child.

Magnitude of the Problem MTCT most significant source of HIV infection in children below age 15. More than 5 million children infected since beginning of epidemic. Almost 4 million children have died. 90% of MTCT occurs in Africa. Transmission higher in developing countries than in industrialized countries due to lack of treatment.

Estimated impact of AIDS on under-5 child mortality rates, select African countries, 2010 250 Deaths per 1000 live births 200 Without AIDS With AIDS 150 100 HIV/AIDS is threatening child survival in many developing countries. This slide shows that unless we do more than what we currently are doing, under-5 child mortality rates will significantly increase by the year 2010 . As you can see, in Botswana, Zambia, Zimbabwe and Kenya U5MRs will more than double. Let us leave the statistics behind and dwell on where we are with PMTCT implementation at both global and regional levels. 50 Botswana Kenya Malawi Tanzania Zambia Zimbabwe Source: US Census Bureau

Routes, Rates,and Risk Factors of Vertical Transmission

HIV Transmission to Infants Less than 60 % of babies born to HIV-positive mothers become infected Peri-natal In utero (during pregnancy) Intrapartum (during delivery) Post-natal Breastfeeding (risk of increases over time. The longer the baby is breastfed the greater the risk of infection)

Father Mother Infant Routes of MTCT of HIV Intercourse Pregnancy Labor & Delivery Breastfeeding Infant

Risk Factors during Breastfeeding Prematurity Duration of breastfeeding Infant immune responses Mixed feeding Maternal viral load Mastitis Mastitis, an inflammatory process in the breast, may be common in lactating women in Africa and is associated with both higher HIV load in breast milk and mother-to-child transmission of HIV

Balancing the Risks of BF and Formula Feeding 12 months 24 months 6 months 14 wks 6 wks Child age Source: Nduati et al. JAMA 2000

Weighing the Risks and Benefits of Breastfeeding with HIV Replacement feeding prevents transmission of HIV through breastfeeding But: Essential to have sterile water Risk of death due to artificial feeding? Cost of replacement feeding? Stigma if not breastfeeding? Early return of fertility?

Risk Factors for MTCT during Pregnancy and Delivery Maternal Factors Stage of maternal HIV disease (viral load) Maternal nutritional status Disruption of placental barrier integrity STD during pregnancy Factors related to the child Genetic characteristics suspected as potential risk Obstetrical Factors Vaginal delivery (versus C-section) First-born of twins Pre-term delivery Hemorrhage during labor Bloody amniotic fluid Invasive procedures Viral Factors MTCT rates higher for HIV-1 than for HIV-2

Benefits of Breastfeeding Benefits for Infants Adequate nutrition Provides protective against infections through maternal antibodies Increase intellectual potential (?) Promotes bonding between mother and infant Benefits for Mothers Facilitates uterine contraction Protects against excessive blood loss Delays the return of normal menstruation Contributes to child spacing Conforms to social norms

Rates of Vertical Transmission Without ART Pregnancy/delivery/breastfeeding…………35% (no intervention) Pregnancy/delivery/replacement feeding….20% (BF contributes 15%)

Risk of Transmission Transmission Rate (%) Timing No BF BF through 6 months BF through 18-24 months During pregnancy 5 – 10 During labor 10 – 20 Through BF Early infection (first 2 months) Late infection (after 2 months) 1 – 5 Overall 15 – 30 25 – 35 30 – 45 Source: De Cock KM et al. 2000.

The Variable Risk of MTCT

Probability of MTCT of HIV (No intervention) Mother Pregnancy/delivery HIV+ Infants (20) HIV- Infants (80) Post partum & BF HIV+ (12) HIV- (68) Estimated outcome based on 100 single births to HIV infected mothers

Probability of MTCT of HIV (Nevirapine) Mother Pregnancy/delivery HIV+ Infants (10) HIV- Infants (90) Post partum & BF HIV+ (14) HIV- (76) Estimated outcome based on 100 single births to HIV infected mothers

Strategies for the Prevention of MTCT

A Comprehensive Approach to Prevent HIV Infection in Infants and Young Children WHO, 2000

Four Integrated Strategies to Reduce Pediatric AIDS (WHO/UNICEF 4 Pillars of MTCT) 3. Prevention of transmission from mother to child 1. Primary prevention of HIV in young adults 4. MTCT-Plus: care and support for HIV+ women, their infants, and families 2. Prevention of unwanted pregnancies among HIV+ women (family planning)

MTCT Prevention components and their contribution to the four-pronged strategy 1. Primary HIV prevention in parents-to-be 2. Prevention of unwanted pregnancy in HIV+ women 3.Prevention of HIV transmission from MTC 4. MTCT-Plus: care & support for HIV+ women and families IEC on prevention and care  Condom promotion VCT Family Planning (dual protection) STI treatment Antenatal care Prophylactic ART regimens Safe delivery practices Support for safer infant feeding Community action to reduce stigma and discrimination and increase support for programs Clinical and community care

Strategy 1: Primary Prevention of HIV Infection Safe sexual behavior and condom use Reproductive health services Management of STIs VCT HIV prevention interventions aimed at pregnant and lactating women, and women of child bearing ages

Strategy 2: Prevention of Unintended Pregnancies in HIV+ Women Strengthening family planning services To prevent unintended pregnancies To delay subsequent pregnancies To replace the contraceptive effect of breastfeeding Access to safe abortion services where allowed by law VCT so that they know their HIV status

Strategy 3: Prevention of Transmission in HIV+ Women Pregnancy and delivery Antiretroviral therapy (ART) Vaginal disinfection (little evidence of success and can increase inflammation) Improved obstetrical practices (avoid unnecessary invasive procedures, safer delivery) Treatment of STIs Breastfeeding Good nutrition and good BF technique instruction Short course ART for baby

Strategy 4: MTCT-Plus Secondary HIV prevention Clinical care (including ART) Community care Stigma reduction OVC services Impact mitigation

Approach to HIV VCT in ANC Settings "Opt in" approach: HIV VCT is offered to pregnant women as a separate intervention from routine ANC and women are requested to provide explicit consent to receive the intervention (VCT) "Opt out" approach: HIV is offered to pregnant women as part and parcel of routine ANC and women are given the option to refuse the intervention based on their personal/individual situation