Backround: Data on Dengue virus (DENV) infection prevalence, geographic distribution and risk factors are necessary to direct appropriate utilization of existing and emerging control strategies. This study aimed to determine the pooled prevalence, risk factors of DENV infection and the circulating serotypes within Nigeria from January 1, 2009 to December 31, 2020. Materials and methods: Twenty-one studies out of 2,215 available articles were eligible and included for this systematic review. Relevant articles were searched, screened and included in this study according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) criteria. The risk of bias in primary studies was assessed by Cochrane's method. Heterogeneity of pooled prevalence was calculated using the chi-square test on Cochrane's Q statistic, which was quantified by I-square values. The random-effects analyses of proportions were used to determine the pooled prevalence of DENV antibodies, antigen and RNA from eligible studies. Results: Of these, 3 studies reported co-circulation of all the 4 serotypes, while 2 separately reported co-circulation of DENV-1&2 and DENV-1 to -3. All the antibody-based studies had significantly high heterogeneity (I-2 > 90%, P < 0.05), while the NS1 and PCR-based studies had low heterogeneity (I-2 < 25%, P > 0.05). The pooled prevalence of DENV IgM, IgG, RNA, NS1 and neutralizing antibodies were 16.8%, 34.7%, 7.7%, 7.7% and 0.7%, respectively. South-east Nigeria had the highest pooled DENV-IgG seropositivity, 77.1%. Marital status, gender, educational level and occupation status, the proximity of residence to refuse dumpsite, frequent use of trousers and long sleeve shirts were significantly associated with DENV IgG seropositivity (P < 0.05). Conclusion: Based on these findings, it can be inferred that Nigeria is hyperendemic for Dengue fever and needs concerted efforts to control its spread within and outside the country.

Usman A, et al. Infect Chemother. 2023 Dec;55:e55. https://doi.org/10.3947/ic.2023.0080

Influenza, Coronavirus Disease 2019 (COVID-19), and respiratory syncytial virus (RSV) are significant contributors to global respiratory illness, causing seasonal epidemics and, in the case of COVID-19 (SARS-CoV-2), a global pandemic. Influenza has historically been well-studied, with subtypes A, B, and C causing recurrent outbreaks, while RSV, though often underappreciated, significantly impacts vulnerable populations like infants and the elderly. Compared to influenza and RSV, SARS-CoV-2 exhibits a broader host range, higher transmissibility, and greater potential for severe systemic complications. This review examines the biology, mechanism of transmission, and epidemiology of these viruses, highlighting features such as antigenic variation in influenza, the zoonotic origins of SARS-CoV-2, and RSV’s seasonal nature. It also explores how COVID-19 public health measures, like social distancing and mask-wearing, affected the spread of influenza and RSV, leading to altered seasonal patterns and the potential for viral co-infections. The review stresses the importance of continued research on these viruses to inform public health strategies, such as antiviral development, vaccination programs, and infection control efforts. Emerging areas like mathematical modelling and molecular research offer new opportunities to predict outbreaks and improve disease management, ultimately reducing the global burden of these respiratory viruses.

Hepatitis B virus (HBV) infection remains a major health challenge in Nigeria, with high prevalence rates among pregnant women. The prevalence of overt and occult hepatitis B infection (HBIOV and HBIOC) among pregnant women was investigated to understand the burden and associated risk factors in this population. A cross-sectional study was conducted among 200 pregnant women. Socio-demographic and clinical data were collected, and blood samples were screened for hepatitis B surface antigen (HBsAg) and hepatitis B virus DNA (HBV-DNA) using Enzyme-Linked Immunosorbent Assay (ELISA) and real time Polymerase Chain Reaction max Eco 48 system. Data were analyzed using GraphPad Prism software (v6) and Statistical Package for the Social Sciences (IBM SPSS 23.0). A significance level of P ≤ 0.05 was considered statistically significant. The overall prevalence of hepatitis B infection was 6.0% (12/200), comprising 2.5% HBIOC and 3.5% HBIOV. The participants, aged 19 to 43 years, were predominantly married (89.5%) and urban-dwelling (69.0%), with diverse educational levels and occupations. There were no statistically significant differences in demographic factors such as age, marital status, or education between HBIOC and HBIOV groups. However, significant associations were observed between HBV infection and risk factors including blood transfusion (p = 0.01), cigarette exposure (p = 0.03), and alcohol consumption (p = 0.01). Viral load was significantly higher in the HBIov group [4.84 log IU/mL (IQR: 4.00–9.14)] compared to the HBIoc group [2.30 log IU/mL (IQR: 2.19–3.00)] (p = 0.001). The findings reveal a 6.0% prevalence of hepatitis B infection among pregnant women, with 3.5% overt and 2.5% occult infections. The results emphasize the need for HBV DNA testing in screening protocols to detect occult and overt HB infections and address key risk factors to improve antenatal care and prevention strategies.

Background: The peripartum period is both a highly vulnerable stage and a significant indicator of a population’s health status. Interest is increasing in human T-cell lymphotropic virus type-1 (HTLV-1) transmission due to its adverse health impacts. However, nationally representative data on HTLV-1 that are important for health planning are unavailable for this subpopulation.Purpose: This study aimed to conduct a pooled estimate of HTLV-1 prevalence among pregnant women in Nigeria to quantify its clinical burden and public health implications.Methods: This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis 2020 statement.Results: After a systematic review of the Nigerian literature, 12 studies (2,821 pregnant or postnatal women) were included in the final evidence synthesis. The estimated HTLV-1 prevalence in Nigerian peripartum women following a positive screening test by enzyme-linked immunosorbent assay was 5.44% (95% confidence interval [CI], 3.16%–9.20%). A subgroup analysis of the 2 major regions showed a slightly higher prevalence in the Western versus Southern region (5.55% [95% CI, 2.49%–11.87%]; and 4.91% [95% CI, 2.11%–11.02%]; P=0.84). However, a subgroup analysis by geopolitical zone revealed that Southwestern and Northwestern Nigeria had the highest prevalence (9.23% [95% CI, 4.35%–18.55%; I2=93%] and 7.15% [95% CI, 1.54%–27.54%]; I2=92%). Our decade-old subgroup analysis found inconsistencies in the HTLV-1 prevalence. Furthermore, our literature review revealed a prevalence of HTLV infection among patients with various clinical types of lymphomas/leukemias and myelopathy of 2%–22%.Conclusion: These findings have important implications in defining the epidemiological patterns of HTLV-1 infection in Nigeria. They also suggest the presence of HTLV-endemic clusters near low-endemic areas, even within the same geopolitical zones.

Background: This study aims to investigate the relationship between CD4+ T-cell counts, alanine ALT levels and HBV-DNA in acute and chronic HBV patients across varying serum ALT levels. Methods: In this cross-sectional study, 200 participants were enrolled, with an equal distribution of acute and chronic hepatitis B virus (HBV)-positive cases. HBsAg, Absolute CD4+ T-cell count, HBsAg, alanine aminotransferase (ALT) and HBV-DNA were measured using standard methods. Cases were grouped into acute or chronic HBV subjects using qualitative laboratory tests. Results: The study found a high prevalence of abnormal ALT levels in HBV-infected cases, with 100% of acute cases and 75% of chronic cases showing increased ALT levels. The median levels of ALT, CD4+ T-cell count, and HBV viral load were compared between acute and chronic HBV-positive cases. The results showed that ALT levels correlated positively with HBV-DNA and CD4 T-cell count, while HBV viral load correlated positively with CD4 T-cell count in acute infected cases only. Interestingly, increasing viral hepatitis B load was associated with a decreased CD4+ T-cell count and increased ALT levels. Conclusion: Our findings shed light on the dynamic nature of HBV infection, highlighting differences between Acute and Chronic cases in terms of liver enzyme levels, immune responses, and viral replication. Abnormal ALT levels may serve as an important clinical indicator of active HBV replication and its potential impact on the immune system. Monitoring these parameters aids in assessing and managing HBV-infected individuals, particularly those with abnormal liver enzyme levels.