These analyses of five years of data from standard and enhanced perinatal HIV surveillance provide important information about trends in the epidemiology and prevention of mother-to-child HIV transmission in St. Petersburg-one of the cities in Russia most affected by HIV. We observed a significant decrease in births among all HIV-infected women, and a decrease in IDUs among HIV-infected women giving birth. Regardless of injection drug use history, we noted impressive improvements in the uptake of clinical services by HIV-infected women giving birth, such as earlier initiation of prenatal care, fewer unintended pregnancies, higher uptake of immunologic and virologic monitoring, earlier initiation and more complete antiretroviral prophylaxis. Most significantly, these improvements in clinical services were followed by a decrease in the rates of mother-to-child HIV transmission from 2005 to 2007.
Our data show that in contrast to the increasing birth rate in the general population of women in St. Petersburg, HIV-infected women are having fewer births. The declining birth rate among HIV-infected women may be a result of increasing age of these women or indicate a decrease in their fertility desires, and/or improved family planning because no increase of abortions was observed in this population during the same time period (personal communication with Dr. Nikolay Belyakov, Director, St. Petersburg City AIDS Center, where 90% of abortions among HIV-infected women are performed). During the last two years of assessment, many HIV-infected women of reproductive age in St. Petersburg received free family planning services, including the contraceptives of their choice . These programmatic improvements likely contributed to the decreases in the birth and unintended pregnancy rates among HIV-infected women. In addition, we observed a decreasing proportion of IDUs among HIV-infected women giving birth, which might be explained by ongoing heterosexual transmission of HIV from HIV-infected male IDUs and some heterosexual transmission outside of the traditional high-risk groups. The improvements of clinical HIV services, albeit more pronounced among women without a history of injection drug use, were evident for both non-IDUs and IDUs.
Perinatal HIV transmission during the first year of surveillance increased, coinciding with no improvements in timing or completeness of antiretroviral prophylaxis. The subsequent decrease of perinatal transmission was most likely due to multiple factors, although earlier initiation and higher effectiveness of antiretroviral prophylaxis were probably the main contributors . Other factors that may have contributed to the decrease in perinatal HIV transmission include a lower rate of unintended pregnancies, earlier initiation of prenatal care, and improved immunologic and virologic HIV monitoring. However, not all women had the benefits of improved clinical services. The steady proportion of women who did not receive prenatal care and ARV prophylaxis, and the increasing trend of injection drug use during pregnancy among IDUs, both indicate that outreach programs are not reaching all women.
Standard HIV surveillance in pregnant women provides important data on trends of the epidemic and overall effectiveness of preventive measures , yet contributes minimally to identifying specific areas for programmatic improvement. Enhanced perinatal surveillance, on the other hand, provides supplementary detailed information on the mother-infant pair, including risk factors, clinical services, and laboratory data, which assists timely evaluation of perinatal prevention efforts [18, 19]. It can be linked with other systems or registries, such as, for example, maternal and infant records at the City AIDS Center. The annual cost of enhanced perinatal surveillance in St. Petersburg was approximately $20,000. If scaled up to a total of five metropolitan areas with highest HIV seroprevalence (i.e., Samara, Irkutsk, Yekaterinburg, Orenburg) , enhanced perinatal surveillance may provide valuable national data on the risk factors for perinatal HIV transmission for considerably less than one percent of the amount spent on HIV prevention in Russia . In St. Petersburg, enhanced perinatal surveillance was critical in identifying areas needing improvement, such as limited use of effective family planning , low infant follow-up , and delayed and less effective antiretroviral prophylaxis . Immediate, focused attention by the local public health leadership made it possible to address each of these issues in a timely fashion through program and policy improvements. As a result, we observed fewer unintended pregnancies, improved infant follow-up, earlier and more effective antiretroviral prophylaxis, and, subsequently, fewer HIV-infected infants.
Our assessment supports the evidence from other countries-improvement of clinical services for HIV-infected women results in significant reductions in perinatal HIV transmission. The success of high-income countries in reducing perinatal HIV transmission was attributed to increased coverage of HIV-infected pregnant women by combination antiretroviral prophylaxis, elective cesarean delivery, and avoidance of breastfeeding [22–24]. Despite a number of challenges in low- and middle-income countries [25, 26], a few reports provide evidence that it is possible to reduce perinatal HIV transmission with implementation of comparable preventive measures [27, 28]. In Ukraine, which had a healthcare system similar to the one in Russia, but had lower coverage by combination antiretroviral prophylaxis at the time of assessment, perinatal HIV transmission was reduced in half in five years (from 15.2% in 2001 to 7.0% in 2006) by strengthening clinical services provided to HIV-infected women . In Russia, where the rate of perinatal HIV transmission has been relatively stable at 6%-8%, the St. Petersburg experience suggests that it is feasible to attain low rates of mother-to-child transmission similar to U.S. and Western European rates. Since our observation of the impact of early and effective antiretroviral prophylaxis on perinatal HIV transmission is consistent with findings from randomized controlled trials from various parts of the world , the data described in this report may be generalizable to other middle-income countries with a large proportion of hospital deliveries and replacement feeding among HIV-infected women giving birth.
The results of this assessment should be interpreted in light of its strengths and limitations. Strengths of the study include almost universal coverage of HIV-infected women giving birth by enhanced perinatal surveillance and standardized data collection methods that allow trend analyses. Although ours is one of the few reports to describe trends in critical indicators of perinatal HIV transmission separately for non-IDUs and IDUs, it is possible that due to social desirability, some women with a history of injection drug use were misclassified as non-IDUs. In additional subgroup analysis (not shown), critical indicators of perinatal transmission among women who reported no history of injection drug use but had hepatitis C coinfection more closely resembled non-IDUs, indicating that the effect of any misclassification of self-reported injection drug use was likely to have been minimal. Another limitation of the study is a large proportion of HIV-exposed infants with undetermined HIV status (e.g., 33.7% during 2007). Previous analysis showed that characteristics of women whose infants had known HIV status were similar to that of the entire population of HIV-infected women. There were, however, some differences: infant HIV status was more likely to be unknown for subgroups with both increased (nonresidents and those with late initiation of antiretroviral prophylaxis) and decreased (those using injection drugs during pregnancy) risk factors for transmission . Therefore, HIV transmission rates can be either underestimated or overestimated.
To our knowledge, this report is the first to document a successful reduction in perinatal HIV transmission in one of the most affected regions in Russia. Our report provides evidence that targeted and comprehensive HIV prevention measures are effective. In addition, this report demonstrates the vital role of enhanced perinatal surveillance in driving programmatic improvements. Scaling up enhanced perinatal surveillance in other key Russian regions will allow effective improvement in local perinatal HIV programs and provide useful data to monitor trends in perinatal HIV transmission. Our data also suggest strategies to further reduce perinatal transmission, which include widespread opt-out HIV testing of women before and during pregnancy and increased outreach to high-risk HIV-infected women to avoid consequences of drug use and facilitate their early contact with and retention in the healthcare system when they become pregnant or are planning pregnancy. In addition, further reductions in perinatal HIV transmission will require full access to effective and affordable family planning services for HIV-infected women. We believe that Russia has the tools to successfully prevent perinatal HIV. The availability of effective antiretroviral regimens, an adequate infrastructure for elective cesarean delivery, and the possibility to safely avoid breastfeeding, should make it feasible to reduce and even eliminate perinatal HIV transmission in Russia.