Alfred Kongnyu Njamnshi

HIV-1 Tat plays a critical role in viral transactivation. Subtype-B Tat has potential use as a therapeutic vaccine. However, viral genetic diversity and population genetics would significantly impact the efficacy of such a vaccine. Over 70% of the 37-million HIV-infected individuals are in sub-Saharan Africa (SSA) and harbor non-subtype-B HIV-1. Using specimens from 100 HIV-infected Cameroonians, we analyzed the sequences of HIV-1 Tat exon-1, its functional domains, post-translational modifications (PTMs), and human leukocyte antigens (HLA)-binding epitopes. Molecular phylogeny revealed a high genetic diversity with nine subtypes, CRF22_01A1/CRF01_AE, and negative selection in all subtypes. Amino acid mutations in Tat functional domains included N24K (44%), N29K (58%), and N40K (30%) in CRF02_AG, and N24K in all G subtypes. Motifs and phosphorylation analyses showed conserved amidation, N-myristoylation, casein kinase-2 (CK2), serine and threonine phosphorylation sites. Analysis of HLA allelic frequencies showed that epitopes for HLAs A*0205, B*5301, Cw*0401, Cw*0602, and Cw*0702 were conserved in 58%–100% of samples, with B*5301 epitopes having binding affinity scores > 100 in all subtypes. This is the first report of N-myristoylation, amidation, and CK2 sites in Tat; these PTMs and mutations could affect Tat function. HLA epitopes identified could be useful for designing Tat-based vaccines for highly diverse HIV-1 populations, as in SSA.

Cameroon is endemic for Buruli ulcer (BU) and organised institutional BU control began in 2002. The objective was to describe the evolution, achievements and challenges of the national BU control programme (NBUCP) and to make suggestions for scaling up the programme. We analysed collated data on BU from 2001 to 2014 and reviewed activity reports NBUCP in Cameroon. Case-detection rates and key BU control indicators were calculated and plotted on a time scale to determine trends in performance. A linear regression analysis of BU detection rate from 2005–2014 was done. The regression coefficient was tested statistically for the significance in variation of BU detection rate. In 14 years of BU control, 3700 cases were notified. The BU detection rate dropped significantly from 3.89 to 1.45 per 100 000 inhabitants. The number of BU endemic health districts rose from two to 64. Five BU diagnostic and treatment centres are functional and two more are planned for 2015. The health system has been strengthened and BU research and education has gained more interest in Cameroon. Although institutional BU control Cameroon only began 30 years after the first cases were reported in 1969, a number of milestones have been attained. These would serve as stepping stones for charting the way forward and improving upon control activities in the country if the major challenge of resource allocation is dealt with. Organised control of Buruli ulcer (BU), the third most common mycobacterial disease, began in Cameroon in 2002. We used 2001–2014 data and activity reports from the National BU Control Programme, to describe the onset, evolution, achievements and challenges of BU control in Cameroon, and make suggestions for improvement and expansion of programme activities. A cumulative number of 3700 BU cases have been detected and treated free-of-charge in five functional BU diagnostic and treatment centres. Sixty-four BU-endemic districts are now confirmed in Cameroon. Furthermore, Cameroon has actively participated in several BU research activities. However major challenges regarding demanding and costly surveillance, education, diagnostic and treatment activities remain to be addressed. Capitalizing on experiences and lessons learned in the past 14 years of activities, the National BU control programme should however be prepared to move forward.

In this study we assess the prevalence, characteristics as well as socio-demographic and clinical correlates of a positive screen for HIV-associated dementia in a group of patients on antiretroviral therapy (ART) in Bamenda, Cameroon. In a cross-sectional study, a structured questionnaire was used to collect data on 400 patients attending the Bamenda Regional Hospital AIDS-treatment Centre. Patients were assessed for neurocognitive function using the International HIV Dementia Scale (IHDS) to assess finger-tapping (FT), alternating hand sequence (AHS) and a 4-word recall (4WR), each scored on a maximum of four. A total of 297 (74%) participants were females. The total IHDS score ranged from 6–12 with a mean of 9.02 and 85% of subjects screened positive for dementia (≤10 on IHDS). Participants performed worst in the AHS assessment with a mean of 2.25 (IQR: 2–3). In multivariable analyses, screening positive for dementia was significantly associated with having primary education or less (aOR: 8.33, 95%CI: 3.85, 16.67), and having HIV symptoms (aOR: 12.16, 95%CI: 3.08, 48.05). A very high proportion of patients on ART screened positive for dementia using the IHDS. This could potentially be an indication of a high prevalence of HIV-associated neurocognitive disorders in this population and or a poor performance of the IHDS in patients on ART. Future studies will need to assess the validity of the IHDS in this population of patients on ART and also evaluate long term outcomes in patients with positive dementia screens.

Skin disorders are generally considered to be more prevalent in the rural areas of Cameroon. This study was carried out to verify this assumption by describing the spectrum of skin disorders in a rural setting of Cameroon.

Introduction: Mother–to-child transmission of HIV is a major public health problem in Cameroon. The aim of this study was to assess knowledge of pregnant women on HIV transmission and prevention, particularly the four pillars of mother-to-child transmission. Materials and Methods: This was a descriptive cross-sectional study from October 2008 to January 2009 at the Yaoundé Gynaecology-Obstetrics and Pediatric Hospital. All women presenting at the Ante-Natal Care (ANC) Clinic for the first time were included in the study after obtaining a verbal informed consent. Results: The ages of the 260 women included in the study ranged from 15 to 42 years. Almost 99% (257/260) of the women interviewed had heard about HIV. Respectively, 80.5% (209/260), 89.3% (232/260) and 81.2% (211/260) of the women cited pregnancy, delivery, and breastfeeding as risk periods for HIV transmission from mother to child. Use of the male condom, the female condom, abstinence, and faithfulness to a single partner were considered as effective methods of HIV prevention by 73% (190/260), 76% (198/260), 88% (229/260) and 46% (120/260) of respondents respectively. About 79% (64/81) of participants with higher education considered HIV infection to be contagious as opposed to 45.5% (5/11) of women with no formal education (P = 0.008). Conclusion: Our data suggest that women have some good knowledge on the Prevention of Mother-To-Child Transmission (PMTCT) of HIV. Nevertheless, improving the formal educational level of these women may contribute to a further reduction of HIV transmission.

The disease burden of human immunodeficiency virus (HIV) - acquired immunodeficiency syndrome (AIDS) is highest in sub-Saharan Africa but there are few studies on the associated neurocognitive disorders in this region. The objectives of this study were to determine whether Western neuropsychological (NP) methods are appropriate for use in Cameroon, and to evaluate cognitive function in a sample of HIV-infected adults. We used a battery of 19 NP measures in a cross-sectional study with 44 HIV+ adults and 44 demographically matched HIV- controls, to explore the validity of these NP measures in Cameroon, and evaluate the effect of viral infection on seven cognitive ability domains. In this pilot study, the global mean z-score on the NP battery showed worse overall cognition in the HIV+ individuals. Significantly lower performance was seen in the HIV+ sample on tests of executive function, speed of information processing, working memory, and psychomotor speed. HIV+ participants with AIDS performed worse than those with less advanced HIV disease. Similar to findings in Western cohorts, our results in Cameroon suggest that HIV infection, particularly in advanced stages, is associated with worse performance on standardized, Western neurocognitive tests. The tests used here appear to be promising for studying NeuroAIDS in sub-Saharan Africa.