Cohort Profile Update: The Bissau HIV Cohort-a Cohort of HIV-1, HIV-2 and Co-infected Patients

Prevalence of hepatitis and HIV infection among 18-months old children in Guinea-Bissau before vaccination

OBJECTIVES

This study reports on the prevalence of hepatitis B virus (HBV) in children in Guinea-Bissau before the hepatitis B vaccine was introduced.

METHODS

Cross-sectional study. From 2005 to 2008, 187 children aged 18 months were enrolled in a vaccine trial and had blood samples taken to test for HBV (HbsAg, anti-HBs and anti-HBc), hepatitis C virus (HCV) and HIV.

RESULTS

HBsAg prevalence was 11.2% and prevalence of any HBV serological marker was 16.0%. No children were positive for HCV. One was positive for HIV-1.

CONCLUSIONS

The prevalence of HBsAg was high compared to other sub-Saharan African countries pre-immunisation, underscoring the importance of broad and sustained HBV vaccination. This study indicates that the majority of HBV transmission is horizontal during childhood in Guinea-Bissau.

The incidence of HIV-2 infection in Spain is declining - a registry data analysis

OBJECTIVES

HIV-2 infection is a neglected disease caused by a human retrovirus that causes AIDS more slowly than HIV-1. Infection with HIV-2 is endemic in West Africa. Given its differential features, guidelines recommend ruling out HIV-2 infection in all newly diagnosed HIV-seropositive individuals.

METHODS

A national registry of HIV-2 cases was created in Spain in 1989, following the first report of three HIV-2+ individuals in Barcelona. The main demographics, clinical, and virological data are reported up to December 2023.

RESULTS

A total of 424 individuals with HIV-2 infection were recorded in the Spanish registry. After a peak in 2009 when 31 cases were reported, new HIV-2 diagnoses steadily decreased. Less than 10 cases/year have been notified since the COVID-19 pandemic. In 2023, only eight cases were reported. Mean age at HIV-2 diagnosis was 44 years old, ranging from birth to 83 years. A total of 265 (62.5%) were male. Migrants predominated, being 322 (76%) Sub-Saharan Africans; however, 60 (14.2%) were native Spaniards. Heterosexual exposure was the most likely route of infection in at least 287 (67.7%) cases. A few cases could be traced to transfusions (n = 4), vertical infection (n = 2), or injection drug use (n = 7). In addition, 15 individuals (3.5%) were men who had sex with men. Coinfection with HIV-1 was recognized in 39 (9.2%) individuals. Molecular characterization of HIV-2 subtypes was performed in 139 individuals, 121 being infected with subtype A and 18 with subtype B.

CONCLUSION

The annual incidence of HIV-2 infection in Spain has decreased after peaking 15 years ago, being the current number of cases below 10 per year. Three-quarters are African migrants, and two-thirds are male. Circulation of HIV-2 in Spain is limited and steadily decreasing.

Clinical presentations and outcomes of HIV-1 and HIV-2 among infected children in Guinea-Bissau: a nationwide study

OBJECTIVES

Disease progression, loss to follow-up, and mortality of HIV-2 compared with HIV-1 in children is not well understood. This is the first nationwide study reporting outcomes in children with the two HIV types in Guinea-Bissau.

STUDY DESIGN

Nationwide retrospective follow-up study.

METHODS

This is a retrospective follow-up study among HIV-infected children <15 years at nine ART centers from 2006 to 2021. Baseline parameters and disease outcomes for children with HIV-2 and HIV-1 were compared.

RESULTS

The annual number of children diagnosed with HIV peaked in 2017. HIV-2 (n = 64) and HIV-1 (n = 1945) infected children were different concerning baseline median age (6.5 vs 3.1 years, P < 0.01), but had similar levels of severe immunodeficiency (P = 0.58) and severe anemia (P = 0.26). Within the first year of follow-up, 36.3% were lost, 5.9% died, 2.7% had transferred clinic, and 55.2% remained for follow-up. Mortality (HR = 1.05 95% CI: 0.53-2.08 for HIV-2) and attrition (HR = 0.86 95% CI: 0.62-1.19 for HIV-2) rates were similar for HIV types.

CONCLUSIONS

The decline in children diagnosed per year since 2017 is possibly due to lower HIV prevalence, lack of HIV tests, and the SARS-CoV-2 epidemic. Children with HIV-2 were twice as old as HIV-1 infected when diagnosed, which suggests a slower disease progression. However, once they develop immunosuppression mortality is similar.