A multi-centre observational study of HIV, tuberculosis and risk of chronic lung disease in urban West Africa.

OBJECTIVE: HIV and tuberculosis (TB) are risk factors for non-communicable chronic lung disease (CLD). Despite the high prevalence of these infections in West Africa, there are no studies that compare CLD between people with HIV and HIV-negative populations in this setting. This study sought to quantify the contribution of HIV and TB infection in addition to conventional CLD risk factors, such as tobacco and biofuel exposure, to CLD in urban West Africa. DESIGN: A multi-centre cross-sectional study was conducted in three community clinics in Lagos, Nigeria between 2018 and 2019. METHODS: Spirometry, questionnaires and clinical records were used to estimate prevalence of CLD and association with risk factors. RESULTS: In total, 148 HIV-negative individuals and 170 HIV-positive individuals completed the study. Current cigarette (11 of 318, 3.5%) and lifetime domestic biofuel (6 of 318, 1.8%) exposures were low. Airway obstruction (33 of 170, 19.4% vs. 12 of 148, 8.1%, P  = 0.004) and CLD (73 of 170, 42.9% vs. 34 of 148, 23%, P  < 0.0001) were more prevalent in people with HIV compared with the HIV-negative group. HIV infection [odds ratio 2.35 (1.33, 4.17), P  = 0.003] and history of TB [odds ratio 2.09 (1.04, 4.20), P  = 0.038] were independently associated with increased risk of CLD. CONCLUSION: HIV and TB far outweigh conventional risk factors, including tobacco and domestic biofuel exposure, as drivers of non-communicable CLD in urban West Africa. Current global policy for CLD may have limited impact on CLD in this setting. Enhanced prevention, diagnosis and management strategies for incident HIV and TB infections are likely to have a significant impact on long-term lung health in sub-Saharan Africa.

SARS-COV-2 antibody responses to AZD1222 vaccination in West Africa.

Real-world data on vaccine-elicited neutralising antibody responses for two-dose AZD1222 in African populations are limited. We assessed baseline SARS-CoV-2 seroprevalence and levels of protective neutralizing antibodies prior to vaccination rollout using binding antibodies analysis coupled with pseudotyped virus neutralisation assays in two cohorts from West Africa: Nigerian healthcare workers (n = 140) and a Ghanaian community cohort (n = 527) pre and post vaccination. We found 44 and 28% of pre-vaccination participants showed IgG anti-N positivity, increasing to 59 and 39% respectively with anti-receptor binding domain (RBD) IgG-specific antibodies. Previous IgG anti-N positivity significantly increased post two-dose neutralizing antibody titres in both populations. Serological evidence of breakthrough infection was observed in 8/49 (16%). Neutralising antibodies were observed to wane in both populations, especially in anti-N negative participants with an observed waning rate of 20% highlighting the need for a combination of additional markers to characterise previous infection. We conclude that AZD1222 is immunogenic in two independent West African cohorts with high background seroprevalence and incidence of breakthrough infection in 2021. Waning titres post second dose indicates the need for booster dosing after AZD1222 in the African setting despite hybrid immunity from previous infection.