High SARS-CoV-2 seroprevalence in Lagos, Nigeria with robust antibody and cellular responses

BackgroundEarly evidence suggested that the impact of the COVID-19 pandemic was less severe in Africa compared to other parts of the world. However, more recent studies indicate higher SARS-CoV-2 infection and COVID-19 mortality rates on the continent than previously documented. Research is needed to better understand SARS-CoV-2 seroprevalence and immunity in Africa. MethodsOur collaboration with the Lagos State COVID-19 Taskforce, enabled secondary analyses of immune responses in healthcare workers (HCWs) and Oxford/AstraZeneca COVID-19 vaccine recipients from the general population across 5 local government areas (LGAs) in Lagos State, Nigeria. Western blots were used to simultaneously detect SARS-CoV-2 spike and nucleocapsid (N) antibodies and stimulation of peripheral blood mononuclear cells with N followed by an IFN-{gamma} ELISA was used to examine T cell responses. FindingsAntibody data demonstrated high SARS-CoV-2 seroprevalence of 71.6% (96/134) in HCWs and 54.8% (63/115) in the general population. Antibodies directed to only SARS-CoV-2 N, suggesting pre-existing coronavirus immunity, were seen in 10.4% (14/134) of HCWs and 20.0% (23/115) of the general population. T cell data showed that IFN-{gamma} responses against SARS-CoV-2 N were robust in detecting exposure to the virus, demonstrating 87.5% sensitivity and 92.3% specificity. InterpretationThese results have important implications for understanding the paradoxical high SARS-CoV-2 infection with low mortality rate in Africa as compared to other parts of the world, as well as for the development of T cell-based diagnostics and vaccines. FundingHarvard University, Motsepe Presidential Research Accelerator Fund for Africa

Prevalence of HIV related oral lesions in people living with HIV and on combined antiretroviral therapy: a Nigerian experience.

INTRODUCTION: oral lesions comprise significant clinical features of HIV infection and are often indicators of immune suppression. However, the advent of antiretroviral therapy has significantly reduced its prevalence. The aim of this study was to relate the prevalence of oral lesions of HIV to treatment outcome of Combined Antiretroviral Therapy (cART) in a Nigerian HIV adult population. METHODS: a cross- sectional study was conducted on 491 People Living with HIV (PLWHIV) on cART from two HIV centres in Lagos state, Nigeria. The EC-clearing house guidelines were employed to categorise oral lesions. Presence or absence of these lesions was reconciled with CD4+ cell count as a measure of efficacy of cART treatment. RESULTS: a total of 491 PLWHIV on cART were enrolled, 366 (74.5%) were females and 125 (25.5%) were males. Age ranged between 18-80 years, with a mean of 41.2 ± 9.1 years. On examination, 12 (2.4%) patients presented with HIV oral lesions. Oral hyperpigmentation (10, 2.0%) was the most common lesion seen, followed by oral ulcers (2,0.4%). Majority (75%) of the affected patients were on a Lamivudine containing regimen. 7 out of the 12 patients with oral lesions had CD4+ cell count between 200-500 cell/mm3 prior to cART initiation. Eleven (92%) of the patients with oral lesions had significant improvement of their CD4+ cell count after cART administration. CONCLUSION: the prevalence of oral lesions in HIV patients on cART therapy in Lagos is low. Oral hyperpigmentation and oral ulcers are the most frequent lesions seen. The presence or absence of oral lesions were not associated with CD4+ cell count. Therefore, we conclude that the oral lesions seen in HIV patients on cART may not be a direct manifestation of the disease.

Cord blood full blood count parameters in Lagos, Nigeria.

INTRODUCTION: Full blood count (FBC), one of the most frequently requested for laboratory investigations, is a simple, fast and cheap test and is a reliable indicator of health. Due to its usefulness in the assessment of health status of individuals, its parameters in cord blood, a major source of haemopoietic stem cell transplantation and an ideal source for laboratory investigations for newborns were determined to provide a useful guide to local neonatologists and stem cell transplant physicians. METHODS: Three millilitres of umbilical cord blood was collected from 130 normal birth weight newborns (69 males and 61 females) whose cord were clamped immediately after delivery, at a teaching hospital in Lagos, Nigeria and full blood count parameters were determined using Sysmex autoanalyzer, model KX-21N. Consented mothers of the newborns were selected based on, age between 18 and 45 years; uneventful pregnancy and delivery and haemoglobin (Hb) concentration ≥ 10 g/dL. RESULTS: There were no statistical gender differences in the mean values of Hb concentrations (M = 13.27 ±1.60 g/dL; F = 13.32±1.61g/dL; p = 0.93), total white cell count (M = 3.16±5.43 × 10(9)/L; F = 13.07±4.98 × 10(9)/L; p= 0.92), platelet count (M= 223.64± 64.21 × 10(9)/L; F = 226.69±80.83 × 10(9)/L; p = 0.81) and other parameters. CONCLUSION: Mean values of full blood count parameters obtained in this study are comparable to reports from other studies in developing countries and could be a useful guide for neonatologists and stem cell transplant physicians in our geographical location.