Prevention of Mother to Child Transmission of HIV

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.

Botswana Kenya Malawi Tanzania Zambia Zimbabwe

0

50

100

150

200

250

Dea

ths

per

100

0 li

ve

bir

ths

Without AIDS

With AIDS

Source: US Census Bureau

Estimated impact of AIDS on under-5 child mortality rates, select African countries,

2010

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

Intercourse

Breastfeeding

Labor & Delivery

Pregnancy

Routes of MTCT of HIV

Risk Factors during Breastfeeding

• Prematurity• Duration of breastfeeding• Infant immune responses• Mixed feeding• Maternal viral load• Mastitis

UNICEF/

Pirozzi

6 wks

14 wks

6 months12 months 24

months

Child age

Source: Nduati et al. JAMA 2000

Balancing the Risks of BF and Formula Feeding

Weighing the Risks and Benefitsof 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– Promotes bonding between mother and infant– Conforms to social norms

• Pregnancy/delivery/breastfeeding…………35%(no intervention)

• Pregnancy/delivery/replacement

feeding….20%(BF contributes 15%)

Rates of Vertical Transmission Without ART

Risk of Transmission

Transmission Rate (%)Timing No BF BF through 6

monthsBF through

18-24 monthsDuring pregnancy 5 – 10 5 – 10 5 – 10

During labor 10 – 20 10 – 20 10 – 20

Through BF

Early infection (first 2 months)

5 – 10 5 – 10

Late infection (after 2 months)

1 – 5 5 – 10

Overall 15 – 30 25 – 35 30 – 45

Source: De Cock KM et al. 2000.

0% 25% 50% 75% 100%

ARV, no breastfeeding, C-section

ARV, no breastfeeding

no ARV, no breastfeeding

ARV, prolonged breastfeeding

no ARV, prolonged breastfeeding

Infected Uninfected

The Variable Risk of MTCT

Probability of MTCT of HIV(No intervention)

Mother

HIV+ Infants

(20)Post partum & BF

HIV- Infants

(80)

Estimated outcome based on 100 single births to HIV infected mothers

HIV+(12)

HIV-(68)

Pregnancy/delivery

Probability of MTCT of HIV(Nevirapine)

Mother

HIV+ Infants

(10)Post partum & BF

Pregnancy/delivery

HIV- Infants(90)

Estimated outcome based on 100 single births to HIV infected mothers

HIV+(14)

HIV-(76)

Strategies for the Prevention of MTCT

UNICEF/90-033/Sprague

WHO, 2000

A Comprehensive Approach to Prevent HIV

Infection in Infants and Young Children

3. Prevention of transmission from mother to child

2. Prevention ofunwanted pregnancies among HIV+ women(family planning)

1. Primary prevention of HIV in young adults

Four Integrated Strategies to Reduce Pediatric AIDS

(WHO/UNICEF 4 Pillars of MTCT)

4. MTCT-Plus: care and support for HIV+ women, their infants, and families

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