Should there b e routine testing for h u m a n immunodeficiency virus infection in p g a ?

T ESTI NG FOR JJUMAN IMMUNODEFICIENCY VIRUS (JJIV) in pregnancy was discussed in a recent Canadian Paediatric Society statement ( 1). New information has become available since that position was taken and, therefore. it is worth revising the question posed in the title. The following is a review of the impact of changing information on the five factors that are of critical importance in a screening program. 1. Sensitivity and specificity of the test: The testing for 111v continues to improve so that the proportion of false-positive tests has become e>..'tremely low. In addi tion, the tests to distinguish the infected infant from the infant with maternal antibodies only have improved so that the diagnosis in the infant can be confirmed by about six months of age instead of 15 months. 2. Acceptability and feasibility ofthe test: The issues discussed in the previous statement about acceptability and feasibility of testing have not ch anged substan tially. Testing includes not only the procedure of the blood test but also counselling and the impact of the result (2). For efficiency. counselling and testing should be included in the routine care of the pregnant woman. Therefore. the issues of feasibility are the purview of those caring for pregnant women. 3. Benefit of early detection: In the previous statement the benefits of early treatment of the infected infant were discussed. However. no comment was made about prevention of transmission of 1 JJV infection to the fetus. Recently. the results of an American study on


T ESTI NG FOR JJUMAN IMMUNODEFICIEN CY VIRUS (JJIV)
in pregnancy was discussed in a recent Canadian Paediatric Society statement ( 1). New information has become available since that position was taken and, therefore. it is worth revising the question posed in the title.
The following is a review of the impact of changing information on the five factors that are of critical importance in a screening program. 1. Sensitivity and specificity of the test: The testing for 111v continues to improve so that the proportion of false-positive tests has become e>..'tremely low. In addition, the tests to distinguish the infected infant from the infant with maternal antibod ies only have improved so that the diagnosis in the infant can be confirmed by about six months of age instead of 15 months.

Acceptability and feasibility ofthe test:
The issues discussed in the previous statement about acceptability and feasibility of testing have not ch anged substantially. Testing includes not only the procedure of the blood test but also counselling and the impact of the result (2). For efficiency. counselling and testing should be included in the routine care of the pregnant woman. Therefore. the issues of feasibility are the purview of those caring for pregnant women.  (3). In a randomized placebo controlled trial (ACTG Study 076). the transmission rate was 8.3% when mothers and their babies received AZr, in comparison with a transmission rate of25.5% among those receiving placebo. The study has now been stopped because this treatment regimen has shown significant effi cacy. This study still leaves many questions unanswered. such as the long term effects of AZr on the fetus and whether treatment of both the mother and baby is necessary for prevention of transmission. Nonetheless , an intervention that will reduce by twothird s the risk of transmission of the virus from the 1 JJV-inf cted pregnant woman to her baby is clearly significant.

Disadvantages oftesting:
The psychosocial difficulties for an asymptomatic woman learning of her 1 JJ Vpositive status must still be considered; for exa mple, violence against women with HIV infection (4). In the previous statement the issue of the long period during which an infant has an 'indeterminate' HIV status was discussed. These issues remain but, fortunately , as the testing for 1 JJV improves, the 'indeterminate' period becomes shorter so that currently a lmost all infected infants can be identified by six months of age.

Prevalence of disease:
In recent studies of prevalence of 1 JJ V infection in women of child-bearing age in Canada. the rates were 1.13/10,000 in Nova Scotia, 8.7/10.000 in Newfoundland and 15.2/10,000 on the island of Montreal (5-7). These rates. though quite variable. O"eooraphically indicate that heterosexual transmission of1 JJV con tinu es to be a problem in Canada and that the number of 1 JJ V-positive pregnant women in Canada is significant. In summary, the new evidence that the rate of transmission of 1 JJV from mother to baby can be reduced by perinatal AZr means that screening pregnant women for 1 JJV infection would not only affect the quality of life for mother and child bul in many cases prevent lhis fata l disease in infants . This preventive strategy requires collaborative efforts by those who care for pregnant women to counsel and lest for Hrv and to offer AZT therapy during pregnancy: by those in lhe delivery room lo provide peripartum AZT: and by those who care for lhe newborn lo continue AZT therapy in lhe n eonate and lo monitor for long term effects of early drug use (8).

REVISED RECOMMENDATIONS
In lhe best interest of children. the Canadian Paediatric Society recommends: 5. If lhe mother has not been tested during pregnancy and if lhe mother has high risk behaviours or is from an area of high seroprevalence. then lesling of lhe mother or newborn is recommended. If lhe mother refuses testing. then the infant should be followed and monitored as an infant of indeterminate III V status . 6. IIIV testing is recommended for abandoned infants or infants to be placed in foster or adoptive care. particularly if testing w ill facilitate decisions for placemen l. 7 . Testing in the perinatal period musl be part of a program that includes post-lest counselling. retesting of the infant and medical care of the infant and mother. 204