Since December 2019, humankind has been experiencing a ravaging severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak, the second coronavirus pandemic in a decade after the Middle East respiratory syndrome coronavirus (MERS-CoV) disease in 2012. Infection with SARS-CoV-2 results in Coronavirus disease 2019 (COVID-19), which is responsible for over 3.1 million deaths worldwide. With the emergence of a second and a third wave of infection across the globe, and the rising record of multiple reinfections and relapses, SARS-CoV-2 infection shows no sign of abating. In addition, it is now evident that SARS-CoV-2 infection presents with neurological symptoms that include early hyposmia, ischemic stroke, meningitis, delirium and falls, even after viral clearance. This may suggest chronic or permanent changes to the neurons, glial cells, and/or brain vasculature in response to SARS-CoV-2 infection or COVID-19. Within the central nervous system (CNS), microglia act as the central housekeepers against altered homeostatic states, including during viral neurotropic infections. In this review, we highlight microglial responses to viral neuroinfections, especially those with a similar genetic composition and route of entry as SARS-CoV-2. As the primary sensor of viral infection in the CNS, we describe the pathogenic and neuroinvasive mechanisms of RNA viruses and SARS-CoV-2 vis-à-vis the microglial means of viral recognition. Responses of microglia which may culminate in viral clearance or immunopathology are also covered. Lastly, we further discuss the implication of SARS-CoV-2 CNS invasion on microglial plasticity and associated long-term neurodegeneration. As such, this review provides insight into some of the mechanisms by which microglia could contribute to the pathophysiology of post-COVID-19 neurological sequelae and disorders, including Parkinson’s disease, which could be pervasive in the coming years given the growing numbers of infected and re-infected individuals globally.

Background: Transfusion transmissible infections, such as HIV, HBV, HCV and syphilis are on the rise and pose a threat to blood safety. Objective: To determine prevalence and demographic profiles of TTI's among first time blood donors in Abeokuta, Nigeria. Methods: The study was conducted between February to November 2013; 130 first time blood donors were tested for the presence of HIV, HBsAg, HCV antibodies and Treponema palidium antibodies using EIA based rapid immunochromatographic kits. Data analysis was done using SPSS with a level of significance of p<0.05. Results: Prevalence rates to HIV, HBsAg, HCV antibody, were 6.2% (n=8), 10% (n=13) and 1.5% (n=2), there was 0% prevalence to Treponema palidium antibodies. Group specific prevalence rates revealed that educational status was associated with HBsAg positivity (p = 0.028), donors with a history of previous blood transfusion was also statistically associated with HIV sero-reactivity (p = 0.013). Conclusions: High levels of HBsAg and HIV were observed, there is need to revise the donor testing algorithm in Nigeria in line with the prevalence of TTI's. We also advocate that a National surveillance system for TTI's be established through our National blood transfusion service (NBTS) program, a second serological test is also suggested to reduce the risk of occult HBV infection in Nigeria.

Highlights We established the introduction of diverse sub-Lineages of Lineage B into Africa within the first few months of the SARSCoV-2 outbreak. The evolutionary rate of SARSCoV-2 sequences in Africa is consistent with previous reports indicating congruence with global viral evolution. The G614 spike protein mutant was the most prevalent in this study.

Persons in the early stages of HIV infection are the major drivers of new infections. These individuals may also develop renal dysfunctions at this time. Nigeria, as other African countries, has one of the highest prevalence of newly diagnosed HIV infections. Despite this, limited information exists on early HIV detection in the continent. This may be related to difficulties in providing early HIV diagnosis and treatment. Patients referred for malaria testing may provide a unique opportunity for early HIV detection. In this study, a method for identifying early HIV-infected individuals was assessed. HIV-1 subtype and renal function biomarkers were also analyzed in these persons. To identify early HIV infection, over a period of 18 months blood samples were collected from persons referred by clinicians for malaria parasite tests in Nigeria. A total of 671 samples were collected and analyzed for HIV antigen/antibody and subtypes. 101 of these samples were categorized into one of four groups: early HIV, chronic HIV, malaria infection and control groups for renal function analysis. 29% of HIV infected individuals were at the early stages of infection. The predominant subtype detected was CRF02_AG (57.14%). The early HIV group had the highest mean serum creatinine (95 µmol/L) and urea (5.7 mmol/L) values across all groups with the difference significant at P < 0.05. There was no significant difference between the circulating subtype and the stage of HIV infection. Our results show the feasibility of screening persons referred for malaria tests for early HIV. This can be used to control new HIV infections in sub-Saharan Africa.

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This study investigated measles infection in vaccinated and unvaccinated children presenting with fever and maculopapular rash during measles outbreaks in the southern and western states of Nigeria. Measles, an acute viral illness caused by a virus in the family Paramyxoviridae, is a vaccine-preventable disease. Measles outbreak is common in Nigeria, despite the national immunization program. Children presenting with symptoms of measles infection in general hospitals and health centers in the states of southern and western Nigeria were recruited for this study. Vaccination history, clinical details, and 5 mL of blood were obtained from the children. Their sera samples were screened for specific immunoglobulin M antibodies to measles virus. Of 234 children tested (124 [53.2%] female), 133 (56.8%) had previously been vaccinated against measles virus, while 93 (39.7%) had not been vaccinated. Vaccination information for eight children could not be retrieved. One hundred and forty-three (62.4%) had measles IgM antibodies. Of these, 79 (55.3%) had been vaccinated for measles, while 65 (44.7%) had not. Despite the ongoing vaccination program in Nigeria, a high number of children are still being infected with measles, despite their vaccination status. Therefore, there is need to identify the reason for the low level of vaccine protection.

IntroductionHIV causes defects in memory B cells in children, but the mechanisms of those defects have not been fully elucidated. One possible mechanism is the lack of T-cell help to B cells during immune reactions. However, few studies have assessed the effect of HIV on follicular helper T cells (TFH cells) in children.MethodsIn this study, follicular-homing CD4 T cells and memory B cells were assessed in HIV-infected children and compared with children from the community. CXCR5 and CD45RO were used as markers of follicular-homing T cells and memory T cells, respectively. Memory TFH cells were identified as CD3+CD8-CD4+CXCR5+CD45RO+PD1+. Central memory T cells were identified based on CCR7 expression. Relationship between the proportions of follicular-homing CD4 T cells and memory B cells were determined in multivariable regression models.ResultsHighly viremic HIV-infected children had lower proportions of memory TFH cells when compared with community control children. In multivariable analyses, high proportions of memory TFH cells were associated with increased percentages of resting memory B cells after adjusting for other covariates.ConclusionThe impact of HIV on follicular helper T cells could influence the accumulation of memory B cells in HIV-infected children.

An understanding of the COVID-19 spread is growing around the world, yet little is known of Africa. This paper explores the time–space geographies of COVID-19 infection focusing on Africa and Nigeria especially. We appraise the global-to-local situation of confirmed cases, deaths and recoveries as well as measures engaged in response to the pandemic. Findings reveal that South Africa accounts for 40% of the total confirmed cases in Africa, followed by Egypt (18%), Nigeria (6.8%), Ghana (4.6%) and Algeria (3.6). Our study shows a significant relationship between population density and COVID-19 cases in Nigeria (R 2 = 0.76; y = 2.43x − 268.7). This expression suggests that high population densities catalyze the spread of COVID-19. While Nigeria has only recorded about 25,964 cases as at the time of writing, the country is struggling to match pressures from rising cases as a result of existing disparities in health care systems.