Background/Objectives: The development of an effective HIV vaccine has faced persistent challenges, as evidenced by the recent discontinuation of the Mosaico phase 3 trial. This study aims to critically examine the obstacles encountered in HIV vaccine development, with a focus on the Mosaico trial, which tested the Ad26.Mos4.HIV vaccine among 3,900 participants across multiple countries. We also explore emerging vaccine technologies and their potential in overcoming these challenges, while reflecting on lessons from previous trials to inform future strategies. Methods: We reviewed the Mosaico trial’s approach, which involved testing the efficacy of the Ad26.Mos4.HIV vaccine. We compared the outcomes of the Mosaico trial with other major HIV vaccine trials, including HVTN 702, Imbokodo, and RV144. We explored the limitations of the immune responses elicited by the Mosaico vaccine. The review focused on the generation of broadly neutralizing antibodies (bNAbs) and the challenges related to antigenic diversity and B-cell engagement. Emerging vaccine technologies, such as virus-like particles (VLPs), nanoparticles, SOSIP trimers, and mRNA platforms, were also analysed for their scalability, immune durability, and potential to advance HIV vaccine development. Results: The Mosaico trial was discontinued due to insufficient efficacy in reducing HIV acquisition, primarily due to the inability of the vaccine to induce bNAbs, which are crucial for targeting the diverse HIV-1 strains. A major challenge was the inadequate engagement of germline B-cell precursors, compounded by the antigenic diversity of the virus. The analysis showed that emerging vaccine platforms, such as VLPs, nanoparticles, SOSIP trimers, and mRNA-based approaches, hold promise but present challenges related to scalability and the durability of immune responses. The role of T cells and adjuvants in enhancing vaccine efficacy was also highlighted as critical for integrating both humoral and cellular immunity. Conclusions: The Mosaico trial, as well as other major HIV vaccine trials, underscores the need for a multi-pronged approach that incorporates both antibody and T-cell responses to tackle the complexities of HIV-1. Future efforts in HIV vaccine development must focus on inducing bNAbs, generating robust T-cell responses, and utilizing scalable vaccine platforms. The integration of artificial intelligence (AI) into vaccine design offers new opportunities to optimize immunogenic targets, which could significantly improve the potential for durable and broad immune protection. The development of a successful HIV vaccine by 2030 is achievable but relies on leverage on advanced technologies including artificial intelligence, innovation and insights from past trial data.

Background: The World Health Organization (WHO) recommends hepatitis D virus (HDV) screening among hepatitis B virus (HBV) infected individuals, with a focus on priority populations in resource-limited settings like Nigeria. HDV infection is a growing public health challenge, particularly among individuals with chronic hepatitis B virus (HBV) infection. HDV accelerates liver disease progression and significantly increases the risk of cirrhosis and hepatocellular carcinoma. Despite this, the epidemiology of HDV in Nigeria remains inadequately documented. This scoping review critically evaluates the prevalence, risk factors, and clinical outcomes of HDV co-infection among HBV patients in Nigeria. Method: We conducted a systematic review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines. The review included observational cross-sectional studies published between 2009 and 2024. We focused on studies that used Immunoglobulin G (IgG) antibody testing or RNA-based diagnostics to assess HDV prevalence. We included PubMed, Google Scholar, and Dimensions databases due to their broad indexing and coverage of peer-reviewed articles and accessibility. We screened the studies for their relevance to HDV prevalence, risk factors, and clinical outcomes, while excluding those that only tested for IgM or HDV antigen. Eleven studies, with a combined sample size of 2308 participants, were included in the final analysis. We performed a narrative synthesis of the findings, considering geographic, gender, and age-based variations in HDV prevalence and clinical impact. Results: HDV prevalence among HBV-infected individuals in Nigeria ranged from 2.0% to 31.6%. The highest prevalence was reported in the Southwest (31.6%) among malaria patients, while lower rates were observed in the Southeast (2.8%). Prevalence was higher in males, particularly those aged 21–30 years in the Southwest and 31–40 years in other regions. RNA-based testing provided more accurate data on active viremia, with viremic HDV prevalence rates ranging from 3.2% to 16%. Triple infection with HIV/HBV/HDV was associated with significantly lower CD4+ cell counts and worse clinical outcomes, including elevated liver enzymes and rapid progression to liver cancer. Key risk factors for HDV co-infection included multiple sexual partners, sharing of needles, and unsafe medical practices. Co-infected patients demonstrated worse clinical outcomes, such as elevated liver enzymes, decompensated cirrhosis, and higher rates of hepatocellular carcinoma. Conclusions: Our review underscores the urgent need for routine HDV screening among HBV patients in Nigeria, especially given the severe clinical consequences of co-infection. The recent WHO guidelines recommending HDV screening align with our findings, which emphasize the importance of RNA-based HDV testing among HBV-positive patients to improve diagnostic accuracy. Public health efforts should prioritize tailored interventions based on geographic, age, and gender disparities in HDV prevalence. Triple infection with HIV/HBV/HDV requires integrated care models to address both immune suppressions as indicated by diminished CD4 cell count and liver disease progression, as these patients face worse outcomes. Targeted HDV screening in mostly affected demographics and geographies and improved Nigeria capacity for cheaper HDV RNA/PCR diagnostics can reduce liver-related morbidity and mortality caused by HBV, which can be worsened and accelerated by HDV coinfection.

Background: Hepatitis C virus (HCV) infection presents a significant public health challenge globally, particularly in high-burden countries like Nigeria, where an estimated 2.4 million individuals are living with HCV. HCV self-testing (HCVST) can potentially bridge the significant diagnosis gap and help individuals to determine their HCV status in the privacy of their homes. It offers a solution to overcome barriers related to stigma and limited access to healthcare. In Nigeria, Self-testing for hepatitis C has only been implemented in a pilot research context. This study aimed to assess stakeholder and community awareness and perceptions of HCVST in Nigeria. The findings will provide insights that could inform effective policies and future scale-up programs for HCV control. Methods: A cross-sectional descriptive study was conducted using an online social media survey administered through SurveyMonkey. The survey was disseminated across social media platforms and groups between October–November 2023. Participants included Nigerians (both health professionals and non-health professionals) aged 18 years or older residing in any of the 36 states and the Federal Capital Territory (FCT). Data collected include sociodemographic characteristics, awareness and perceptions of HCVST, and perceived benefits and barriers. Results: Of 321 respondents, 94% perceived HCVST as highly important. While 77% of respondents knew about HIVST, only 58% had prior knowledge of HCVST. The analysis also showed that healthcare workers had greater awareness of HIV self-testing (82.3%) compared to non-healthcare workers (50.0%). Most respondents (88%) were highly likely to recommend HCVST and perceived it as a cost-effective alternative to traditional testing. Key perceived benefits included increased disease detection and control (67%), improved access to testing (21%), and reduced stigma (11%). In the unadjusted model, geographical zone (Southern Nigeria: cOR = 0.49, 95% CI: 0.30–0.77, p = 0.002), work experience (more than 20 years: cOR = 2.79, 95% CI: 1.11–8.07, p = 0.039), and prior awareness of HIV self-testing (cOR = 5.24, 95% CI: 3.00–9.43, p < 0.001) were significant predictors of HCVST awareness. However, in the adjusted model, only prior awareness of HIV self-testing remained significant (aOR = 4.77, 95% CI: 2.62–8.94, p < 0.001). Conclusions: The strong support for HCVST among stakeholders in Nigeria highlights its potential to enhance HCV control, especially within the broader context of infectious diseases like STIs. The greater awareness of HIV self-testing among healthcare workers compared to non-healthcare workers indicates the need for targeted awareness campaigns for non-healthcare populations. Addressing these awareness gaps, leveraging lessons from HIVST, and using existing infrastructure will be crucial. Prioritizing public education, outreach, and effective linkage to care will drive the impact of HCVST in achieving HCV elimination goals and position it as a model for expanding similar STI interventions in Nigeria.

Background: Viral hepatitis B and C (HBV and HCV) pose significant public health concern in Nigeria, where access to healthcare and treatment affordability are limited. This study investigated sociodemographic and clinical predictors of health insurance coverage and access to care among patients with HBV and HCV in Nasarawa State, Nigeria. Methods: A cross-sectional facility-based study was conducted at two secondary hospitals in Nasarawa State, Nigeria. Participants included patients diagnosed with HBV, HCV, or both who were ≥18 years old. Data were collected using a structured questionnaire covering sociodemographic and clinical information, health insurance details, and economic impact. Binary logistic regression was used to analyze the relationship between sociodemographic/clinical factors and health insurance status. Results: Out of 303 participants, 68% had health insurance, which mostly covered hepatitis screening and vaccination. Significant predictors of health insurance coverage included being aged 36–40 years (adjusted odds ratio [aOR]: 11.01, 95% confidence interval [CI]: 2.38–50.89, p = 0.002), having post-secondary education (aOR: 25.2, 95% CI: 9.67–65.68, p < 0.001), being employed (aOR: 27.83, 95% CI: 8.85–87.58, p < 0.001), and being HIV-positive (aOR: 4.06, 95% CI: 1.55–10.61, p = 0.004). Nearly all those insured (99%) faced restrictions in insurance coverage for viral hepatitis services. Conclusions: This study reveals that while health insurance coverage is relatively high among viral hepatitis patients in Nasarawa State, significant restrictions hinder access to comprehensive services, especially for vulnerable groups like younger adults, the unemployed, and PLHIV. Key factors influencing coverage include age, education, employment, and HIV status. Expanding benefit packages to include viral hepatitis diagnosis and treatment, raising awareness about viral hepatitis as part of insurance strategy, improving access for underserved populations, and integrating hepatitis services into existing HIV programs with strong policy implementation monitoring frameworks are crucial to advancing universal health coverage and meeting the WHO’s 2030 elimination goals.

The growing exposure to occupational chemicals and the spread of human immunodeficiency virus (HIV) infection are major global health issues. However, there is little data on the carcinogenic risk profile of HIV-infected individuals who have been occupationally exposed to chemical mixtures. This study therefore investigated the levels of cancer risk biomarkers in HIV-infected individuals exposed to occupational chemicals, exploring the relationship between apoptotic regulatory and oxidative response markers as a measure of cancer risk. Study participants (mean age 38.35±0.72 years) were divided into four groups according to their HIV status and occupational chemical exposure: 62 HIV-positive exposed (HPE), 66 HIV-positive unexposed (HPU), 60 HIV-negative exposed (HNE), and 60 HIV-negative unexposed (HNU). Serum p53, β-cell lymphoma-2 (bcl2), 8-hydroxydeoxyguanosine (8-OHdG), superoxide dismutase (SOD), and malondialdehyde (MDA) were measured using standard methods. Clusters of differentiation 4 (CD4⁺) T-lymphocytes were enumerated using flow cytometry. Serum p53 and bcl2 levels in HPE (0.91±0.11ng/ml and 122.37±15.77ng/ml) were significantly lower than HNU (1.49±0.15ng/ml and 225.52±33.67ng/ml) (p < 0.05), respectively. Wildtype p53 and bcl2 were positively and significantly correlated with 8-OHdG (r = 0.35, p<0.001; r = 0.36, p<0.001) and SOD (r = 0.38, p<0.001; r = 0.39, p<0.001). After controlling for gender, age, BMI, and cigarette smoking, both HIV status and SOD activity were significantly associated with wildtype p53 and bcl2 (p < 0.05). Malondialdehyde was significantly higher in the HPE (0.72 ± 0.01 mg/ml) than in the HNE (0.68 ± 0.01 mg/ml) and HNU (0.67 ± 0.01 mg/ml) groups (p < 0.05). The HPE group showed significantly lower CD4 counts than the HNE and HNU groups. Individuals who are HIV-infected and occupationally exposed to chemicals have a constellation of depressed immunity, elevated oxidative stress, and loss of tumour suppressive functions, which together intensify cancer risk, providing valuable scientific and public health bases for preventive measures in this vulnerable population.

The growing exposure to occupational chemicals and HIV infection are both major global health issues. However, there is little data on the carcinogenic risk profile of HIV-infected individuals who have been occupationally exposed to chemical mixtures. This study therefore investigated the levels of cancer risk biomarkers in HIV-infected individuals exposed to occupational chemicals, exploring the relationship between apoptotic regulatory markers and DNA oxidative response markers as a measure of cancer risk. Apparently healthy adults (mean age 38.35±0.72years) were divided into four groups according to their HIV status and occupational chemical exposure: 62 HIV positive exposed (HPE), 66 HIV positive unexposed (HPU), 60 HIV negative exposed (HNE), and 60 HIV negative unexposed (HNU). Serum p53, bcl2, 8-hydroxydeoxyguanosine (8-OHdG), superoxide dismutase (SOD), and malondialdehyde (MDA) were estimated by standard methods. Blood samples were analysed for CD4 cell count by flow cytometry. Serum p53 and bcl2 levels in HPE (0.91±0.11ng/ml and 122.37±15.77ng/ml) were significantly lower than HNU (1.49±0.15ng/ml and 225.52±33.67ng/ml) (p < 0.05), respectively. Wildtype p53 and bcl2 were positively and significantly correlated with 8-OHdG (r=0.35, p<0.001; r=0.36, p<0.001) and SOD (r=0.38, p<0.001; r=0.39, p<0.001). After controlling for gender, age, BMI, and cigarette smoking, both HIV status and SOD activity were significantly associated with wildtype p53 and bcl2 (p < 0.05). Malondialdehyde was significantly higher in the HPE (0.72 ± 0.01 mg/ml) than in the HNE (0.68 ± 0.01 mg/ml) and HNU (0.67 ± 0.01 mg/ml) groups (p < 0.05). Additionally, the HPE group (578.87±33.64 cells/µL) exhibited significantly lower CD4 counts than the HNE (785.35±36.8 cells/µL) and HNU (862.15±43.29 cells/µL) groups. Individuals infected with HIV and occupationally exposed to chemical substances exhibit compromised immunity, elevated oxidative stress, and depressed p53 (loss of tumour suppressive capacity) and bcl2; a convergence promoting the carcinogenic pathway and elevated cancer risk. These findings provide a mechanistic basis of cancer risk and scientific justification for preventive strategies against carcinogenesis in individuals who are HIV-infected.