Antenatal testing targets reached in England and Scotland

The UK’s policy of universal antenatal HIV testing reached a Government-set target in England and Scotland in 2003-4 for the diagnosis of HIV infection in pregnant women prior to delivery. This appears to be the first time this target has been met since its implementation, according to a report from the Health Protection Agency (HPA) published in the May 19th edition of Eurosurveillance Weekly.

In 1999, the UK Government’s Department of Health (DoH) established national targets for offering and recommending HIV tests to all pregnant women in England, Wales and Scotland as a routine part of antenatal care. The DoH’s intention was to increase the uptake of antenatal HIV testing to 90% and to increase the proportion of HIV infections diagnosed prior to delivery to 80%. The hope was that, by December 2002, this would result in an 80% reduction in the proportion of infants acquiring HIV infection at birth.

However, an interim report for 2002 found an antenatal detection rate of only 53% in London and of at least 67% in Scotland. Since then, the HPA have estimated that the 80% target has now met by in all areas, although until now there have been no published supporting data.

How the numbers are estimated

The estimated HIV prevalence in both diagnosed and undiagnosed pregnant women is carried out in several representative locations in England and Scotland. Dried blood spots in newborns are tested anonymously in order to discover whether the newborns carry the mother’s anti-HIV antibodies. This information is then added to data from the National Study of HIV in Pregnancy and Childhood (NHSPC), which receives confidential reports of both the timing of the mother’s HIV diagnosis and the number of births to diagnosed HIV-positive women throughout the UK. Together, this allows the HPA to estimate the proportion of maternal HIV infections that were diagnosed before delivery, and work out the detection rate of the antenatal screening programme.

Scotland, 2004

HIV prevalence in pregnant women in Scotland increased from 3.2/10,000 in 2003 to 5.2/10,000 in 2004, resulting in 28 HIV-positive women giving birth in Scotland in 2004, which is the highest-ever figure. Information on country of birth of mothers was available for 26 of the 28 women; of the 26, 13 had been born outside of the UK.

Only three of the 28 HIV-positive pregnant women (11%) remained undiagnosed at delivery, resulting in an 89% detection rate, which is well above the 80% target. Fifteen of the women were diagnosed prior to pregnancy and ten were diagnosed during the pregnancy. Still, this means that 23% (three of thirteen) HIV-positive women who were not aware of their HIV status at the start of their pregnancy remained undiagnosed during their pregnancy.

England, 2003

HIV prevalence in pregnant women has risen sharply in all English regions since 2000. In 2003, HIV prevalence in pregnant women in England was highest in London with an overall prevalence of 45/10,000 in 2003. Outside London, HIV prevalence was estimated to be 9/10,000 in 2003. HIV prevalence was estimated to be 2.38% in women born in sub-Saharan Africa, compared with 0.03% and 0.07% among women born in the UK and the rest of the world, respectively.

The HPA estimate that only 12% of HIV-positive women remained undiagnosed at delivery, compared with 26% in 2000, and resulting in an 88% detection rate.

Conclusion

Although there are much more detailed, and recent, data provided for Scotland than for England, there does appear to be an increase in the proportion of women who are having their HIV infection diagnosed antenatally.

The authors suggest “these data demonstrate how the universal offer and recommendation of HIV testing has resulted in the improvement in detection rates and uptake of available interventions. This has been followed by a reduction in the proportion of children exposed to maternal HIV infection who go on to acquire HIV.”