Prevalence of human immunodeficiency virus (HIV) antibody among apparently healthy pregnant women in Nigeria

Systematic review and meta-analysis of seroprevalence of human immunodeficiency virus serological markers among pregnant women in Africa, 1984-2020

BACKGROUND

Human immunodeficiency virus (HIV) is a major public health concern, particularly in Africa where HIV rates remain substantial. Pregnant women are at an increased risk of acquiring HIV, which has a significant impact on both maternal and child health.

AIM

To review summarizes HIV seroprevalence among pregnant women in Africa. It also identifies regional and clinical characteristics that contribute to study-specific estimates variation.

METHODS

The study included pregnant women from any African country or region, irrespective of their symptoms, and any study design conducted in any setting. Using electronic literature searches, articles published until February 2023 were reviewed. The quality of the included studies was evaluated. The DerSimonian and Laird random-effects model was applied to determine HIV pooled seroprevalence among pregnant women in Africa. Subgroup and sensitivity analyses were conducted to identify potential sources of heterogeneity. Heterogeneity was assessed with Cochran's Q test and I2 statistics, and publication bias was assessed with Egger's test.

RESULTS

A total of 248 studies conducted between 1984 and 2020 were included in the quantitative synthesis (meta-analysis). Out of the total studies, 146 (58.9%) had a low risk of bias and 102 (41.1%) had a moderate risk of bias. No HIV-positive pregnant women died in the included studies. The overall HIV seroprevalence in pregnant women was estimated to be 9.3% [95% confidence interval (CI): 8.3-10.3]. The subgroup analysis showed statistically significant heterogeneity across subgroups (P < 0.001), with the highest seroprevalence observed in Southern Africa (29.4%, 95%CI: 26.5-32.4) and the lowest seroprevalence observed in Northern Africa (0.7%, 95%CI: 0.3-1.3).

CONCLUSION

The review found that HIV seroprevalence among pregnant women in African countries remains significant, particularly in Southern African countries. This review can inform the development of targeted public health interventions to address high HIV seroprevalence in pregnant women in African countries.

Monitoring of HIV-1 infection prevalence and trends in the general population using pregnant women as a sentinel population: 9 years experience from the Kagera region of Tanzania

In the Kagera region of Tanzania, a population-based study was initiated in 1987 followed by the establishment of antenatal-clinic-based sentinel surveillance system in the town of Bukoba in 1990. Repeat studies in both populations in Bukoba in 1993 and 1996 made it possible to study the dynamics of HIV infection prevalence and incidence in the area. This study aims at comparing the findings from this sentinel surveillance system with those of cross-sectional studies in the general population to assess its validity in estimating HIV prevalence and their trends in the general population. A multistage cluster sampling technique was used in the population-based studies whereas the antenatal-clinic-based population was obtained by consecutively recruiting antenatal care attenders coming for the first time during a given pregnancy. Antibodies against HIV infection were tested using two independent enzyme-linked immunosorbent assay (ELISA) antibody detection tests. Unlinked anonymous testing strategy was adopted for the sentinel population. Age-adjusted prevalence among antenatal care attenders decreased from 22.4% (95% confidence interval [CI], 20.6-25.2) in 1990 to 16.1% (95% CI, 15.9-18.8) in 1993 and further to 13.7% (95% CI, 11.8-14.3) in 1996. These results closely resemble those of the general population of adult women in the clinic's catchment area (the town of Bukoba) where the age-adjusted prevalence of 29.1% (95% CI, 24.4-34.6) in 1987 showed a decrease in the studies in 1993 18.7% (95% CI, 15.1-23.0) and in 1996 14.9% (95% CI, 12.0-17.1). The study indicates that general population trend estimates can be generated using sentinel surveillance data based on pregnant women visiting an antenatal clinic for the first time during a given pregnancy. The benefits of using this group outweigh its limitations that are brought about by possible selection bias. Continued surveillance of the epidemic based on antenatal care patients as a sentinel population is therefore recommended.

Seroprevalence and coprevalence of HIV and HBsAg in Nigerian children with/without protein energy malnutrition

In order to assess the seroprevalence and coprevalence of hepatitis-B surface antigen (HBsAg), human immunodeficiency virus-1 and -2 (HIV-1 and -2) antibodies in Nigerian children with/without protein energy malnutrition (PEM), we studied plasma specimens of 206 children with PEM and 200 apparently healthy reference children aged between 1 and 3 years by enzyme-linked immunosorbent assays (ELISA). HIV-seropositive cases were confirmed by immunoblotting (IB). Of the children studied, eight (4%) of the healthy and four (1.9%) of the malnourished (P = 0.22, Fisher's exact test) were positive for HIV-1 antibodies, 40 (20%) of the healthy and 54 (26%) of the malnourished (P = 0.14) were positive for HBsAg, and five (2.5%) of the healthy and four (1.9%) of the malnourished (P = 0.70) were positive for both HIV-1/HBsAg. No case of HIV-2 antibodies was found. While the seroprevalence of HBsAg was higher in the malnourished subjects, the reverse was the case with HIV antibodies. However, all the four HIV-1-positive malnourished children and five of eight of the HIV-1-positive reference children were simultaneously positive for HBsAg. This is the first epidemiological report on the seroprevalence and coprevalence of HIV and HBsAg in apparently healthy and malnourished Nigerian children.