Prevention of vertical HIV transmission and management of the HIV-exposed infant in Canada in 2014.

Abstract

The standard of care for the prevention of vertical transmission (VT) of HIV in Canada and other developed countries includes routine prenatal HIV testing for all pregnant women, and for those testing positive: antepartum combination antiretroviral therapy (cART); intrapartum intravenous zidovudine; six weeks of postnatal oral zidovudine to the infant; and exclusive formula feeding of the infant. With these interventions, the rate of VT has been reduced from 25% to 40%, to 4 weeks before delivery. The purpose of the present article is to highlight recent changes in management guidelines and important caveats to these changes with regard to prevention of VT in the Canadian context. There is a global trend to replace the use of the previous conventional terminology of ‘mother-to-child transmission’ with ‘vertical transmission’ or ‘perinatal transmission’ to remove implications of blame from the mother. In the present article, ‘vertical transmission’ is used throughout. HIV testing during pregnancy HIV testing is recommended for all pregnant women in Canada, with appropriate pre- and post-test counselling. Women whose HIV status is unknown at the time of delivery should undergo rapid HIV antibody testing. For women at increased risk for HIV infection (eg, intravenous drug use, commercial sex work, frequent unprotected intercourse with multiple partners, HIV-negative woman of a serodiscordant couple) who test negative early in pregnancy, repeat testing late in pregnancy (beginning of the third trimester) and at delivery is strongly encouraged. When such women present in labour, advice regarding maternal HIV diagnosis and management should be sought from obstetric and adult HIV experts on an urgent basis; similarly, pediatric HIV experts should be consulted regarding infant management in such situations. Women living with HIV, either previously diagnosed or identified during pregnancy, should be followed by a specialist with expertise in the management of HIV during pregnancy, treated with cART and monitored for viral suppression. Prelabour elective Cesarean section delivery should be planned for those not on cART and/or anticipated or documented to have inadequate viral suppression near delivery (viral load >1000 copies/mL). For women who were previously diagnosed with HIV in whom viral load is not documented to be fully suppressed in the four weeks preceding onset of labour and for women diagnosed with HIV infection at the time of labour, urgent consultation with adult and pediatric HIV experts and an obstetrician with expertise in the management of HIV is essential. Recommendation 1: Pediatricians and other health care providers involved in the care of HIV-infected pregnant women and their children should advocate for universal HIV testing of all pregnant women with appropriate pre- and post-test counselling so that appropriate preventive measures can be implemented in a timely manner. When this fails, testing of the mother at delivery, or of the infant if maternal testing is not possible, should be ensured. Ideally, no infant should be discharged from hospital without the HIV status of the mother being known. Pediatricians and family physicians who perform routine neonatal examinations should verify that the HIV status of the mother or child is known and documented. Recommendation 2: Urgent consultation with an obstetrician with HIV expertise and an adult HIV expert is recommended for diagnosis and management of women deemed to be at high risk for HIV infection with unknown status at the time of labour. Similarly, a pediatric HIV expert should be consulted regarding infant management in such situations.