Antifungals susceptibility pattern of Candida spp. isolated from female genital tract at the Yaoundé Bethesda Hospital in Cameroon

Introduction: Vaginal candidiasis is considered as an important public health problem worldwide and its incidence has increased nowadays. In recent years, inappropriate and disproportionate use of antifungal drugs, automedication as well as non compliance have caused drug resistance. Methods: This study aimed at determining the in vitro antifungal susceptibility patterns of Candida speciesisolated from female genital tract at Yaoundé Bethesda Hospital in Cameroon. Two hundred and fourthy five women (age range: 15 years to 49 years) attending the hospital were recruited between January and June 2014 in this cross sectional study. Vaginal smears were collected using sterile swabs from each participant and cultured on sabouraud dextrose agar supplemented with chloramphenico l 0.5%; identification of Candida spp. was performed following standard methods. The disk diffusion method was used for antifungal susceptibility testing. Results: Out of the 245 vaginal smears collected, 94 (38.4%) strains of yeast were isolates among which 43 (45.7%) were Candida albicans and 51 (54.3%) were non albicans. The highest susceptibility of the isolates was seen for nystatin 62 (83.78%), ketoconazole 61 (82.43%) and fluconazole 60 (81.08%). Conclusion: Despite the noticeable resistance of Candida spp. isolates to miconazole and itraconazole, the results indicate that nystatin, ketoconazole and fluconazole are the drugs of choice for the therapy of vaginal candidiasis in this region

Prevalence of drug-resistant mutations in newly diagnosed drug-naïve HIV-1-infected individuals in a treatment site in the Waterberg District, Limpopo province

Aim. We studied the prevalence of resistance mutations in drug-naïve HIV-infected individuals at the Bela-Bela treatment site to gather information on the presence of antiretroviral (ARV) drug-resistant viruses in drug-naïve populations, so as to improve treatment guidance. Subjects and methods. Drug-naive HIV-1-infected individuals were sequentially recruited between February 2008 and December 2008 from individuals visiting the voluntary counseling and testing (VCT) services of the Bela-Bela HIV/AIDS Wellness Clinic. Viral subtyping was done by phylogenetic analysis; drug-resistant mutations were determined according to the Stanford HIV Drug Resistance Interpretation and the International AIDS society-USA guidelines. Results. A drug-resistant mutation prevalence of 3.5% (95% confidence interval 0.019796 - 0.119077) comprising Y181C and L33F was observed; 98% of the viruses were HIV-1 subtype C on the protease (PR) and reverse transcriptase (RT) gene regions. Conclusion. The prevalence of drug-resistant mutations in drug-naïve persons may be low in Bela-Bela after 8 years of access to antiretroviral treatment (ART), and resistance testing before initiating treatment may not be needed

Prevalence of Antiretroviral Drug Resistance Mutations and HIV-1 Subtypes among Newly-diagnosed Drugna\uefve Persons Visiting a Voluntary Testing and Counselling Centre in Northeastern South Africa

Data on antiretroviral drug resistance among drug-na\uefve persons are important in developing sentinel surveillance policies. This study was conducted to determine the prevalence of antiretroviral drug resistance mutations among drug-na\uefve HIV-infected individuals attending a voluntary testing and counselling centre at the Mankweng Hospital in northeastern South Africa. In total, 79 drug-na\uefve HIV-positive individuals were sequentially recruited during February 2008-December 2008. Drug resistance mutations were determined using the calibrated population resistance tool available on the Stanford HIV drug resistance database. Viral DNA was obtained from 57 (72%) of the 79 individuals. Reliable nucleotide sequences were obtained for 54 reverse transcriptase (RT) and 54 protease (PR) gene regions from 54 individuals. Overall, five sequences (9.3%) harboured drug resistance mutations (95% confidence interval -1.53 to 16.99). Four (7.4%) of these were nucleoside RT inhibitor mutations (D67G, D67E, T69D, and T215Y), and one (1.9%) was a PR inhibitor mutation (M46I). No major non-nucleoside RT resistance mutation was detected. Several minor resistance mutations and polymorphisms common in subtype C viruses were observed in the PR and RT genes. Phylogenetic analysis of the partial pol sequences showed that 52 (96%) of the 54 isolates were HIV-1 subtype C. One isolate (08MB08ZA) was HIV-1 subtype B while another (08MB26ZA) was related to HIV-1 subtype J. HIV-1 subtype recombination analysis with REGA assigned the pol sequence to HIV subtype J (11_cpx) with a bootstrap value of 75%. The prevalence of drug resistance mutations observed in the population studied was relatively higher than previously reported from other parts of South Africa. In addition, this is apparently the first report of an HIV-1 subtype J-like virus from northeastern South Africa

Evaluation of bat adenoviruses suggests co-evolution and host roosting behaviour as drivers for diversity.

Adenoviruses (AdVs) are diverse pathogens of humans and animals, with several dozen bat AdVs already identified. Considering that over 100 human AdVs are known, and the huge diversity of bat species, many bat AdVs likely remain undiscovered. To learn more about AdV prevalence, diversity and evolution, we sampled and tested bats in Cameroon using several PCR assays for viral and host DNA. AdV DNA was detected in 14 % of the 671 sampled animals belonging to 37 different bat species. There was a correlation between species roosting in larger groups and AdV DNA detection. The detected AdV DNA belonged to between 28 and 44 different, mostly previously unknown, mastadenovirus species. The novel isolates are phylogenetically diverse and while some cluster with known viruses, others appear to form divergent new clusters. The phylogenetic tree of novel and previously known bat AdVs does not mirror that of the various host species, but does contain structures consistent with a degree of virus-host co-evolution. Given that closely related isolates were found in different host species, it seems likely that at least some bat AdVs have jumped species barriers, probably in the more recent past; however, the tree is also consistent with such events having taken place throughout bat AdV evolution. AdV diversity was highest in bat species roosting in large groups. The study significantly increased the diversity of AdVs known to be harboured by bats, and suggests that host behaviours, such as roosting size, may be what limits some AdVs to one species rather than an inability of AdVs to infect other related hosts

Kinetics of CD4+ T-cell recovery amongst HIV load suppressed patients on first-line antiretroviral therapy in Yaoundé, Cameroon

HIV infected patients on Antiretroviral Therapy (ART) are exposed to various immunological disorders. Immune reconstitution is one of the most challenging problem linked to morbidity and mortality in HIV patients. This study aimed at evaluating the kinetics of CD4+ T-cell recovery amongst HIV load suppressed patients on first-line ART in Yaoundé, Cameroon. This was a retrospective cohort study performed at the care and treatment units of the Yaoundé University Teaching Hospital and Essos Hospital Center, with viral suppressed patients initiated on ART between March and July 2015. Data were collected using a standard form and analyzed using R.3.6.2 software. A p<0.05 was considered statistically significant for a 95%CI. Of the 499 viral suppressed participants, 32% (n=160) were male and 68% (n=339) female; 33% and 40% had severe and moderate immunodepression at baseline, respectively; 9% and 28% remain respectively on the same immunological state. CD4+ T-cell count increased by 73%, 49% and 29% for patients that started treatment, with CD4+ <150 cells/ml, 150<CD4+<350 cells/ml and 350<CD4+<500 cells/ml, respectively and 14%, 34% and 40% reached a target of 500 cells/ml or more after 4 years of treatment. Elder patients and males were likely to have CD4+ T-cells less than 350 Cells/ml. Approximately 35% of patient started treatment with CD4+ T-cells <350 Cells/ml. CD4+ T-cells increased significantly during 4 years of treatment but, just 29% in average achieved CD4+ ≥ 500 cells/ml. CD4 T-cells recovery represent and important challenge in the immunological monitoring of long-term HIV infected patients on ART

Wildlife in Cameroon harbor diverse coronaviruses, including many closely related to human coronavirus 229E.

Zoonotic spillover of animal viruses into human populations is a continuous and increasing public health risk. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) highlights the global impact of emergence. Considering the history and diversity of coronaviruses (CoVs), especially in bats, SARS-CoV-2 will likely not be the last to spillover from animals into human populations. We sampled and tested wildlife in the Central African country Cameroon to determine which CoVs are circulating and how they relate to previously detected human and animal CoVs. We collected animal and ecological data at sampling locations and used family-level consensus PCR combined with amplicon sequencing for virus detection. Between 2003 and 2018, samples were collected from 6,580 animals of several different orders. CoV RNA was detected in 175 bats, a civet, and a shrew. The CoV RNAs detected in the bats represented 17 different genetic clusters, coinciding with alpha (n = 8) and beta (n = 9) CoVs. Sequences resembling human CoV-229E (HCoV-229E) were found in 40 Hipposideridae bats. Phylogenetic analyses place the human-derived HCoV-229E isolates closest to those from camels in terms of the S and N genes but closest to isolates from bats for the envelope, membrane, and RNA-dependent RNA polymerase genes. The CoV RNA positivity rate in bats varied significantly (P < 0.001) between the wet (8.2 per cent) and dry seasons (4.5 per cent). Most sampled species accordingly had a wet season high and dry season low, while for some the opposite was found. Eight of the suspected CoV species of which we detected RNA appear to be entirely novel CoV species, which suggests that CoV diversity in African wildlife is still rather poorly understood. The detection of multiple different variants of HCoV-229E-like viruses supports the bat reservoir hypothesis for this virus, with the phylogenetic results casting some doubt on camels as an intermediate host. The findings also support the previously proposed influence of ecological factors on CoV circulation, indicating a high level of underlying complexity to the viral ecology. These results indicate the importance of investing in surveillance activities among wild animals to detect all potential threats as well as sentinel surveillance among exposed humans to determine emerging threats

Clinical Manifestations of an Outbreak of Monkeypox Virus in Captive Chimpanzees in Cameroon, 2016

Monkeypox virus (MPXV) is a re-emerging virus of global concern. An outbreak of Clade I MPXV affected 20 captive chimpanzees in Cameroon in 2016. We describe the epidemiology, virology, phylogenetics, and clinical progression of this outbreak. Clinical signs included exanthema, facial swelling, peri-laryngeal swelling, and eschar. Mpox can be lethal in captive chimpanzees with death likely resulting from respiratory complications. We advise avoiding anesthesia in animals with respiratory signs to reduce the likelihood of death. This outbreak presented a risk to animal care staff. There is a need for increased awareness and a One Health approach to preparation for outbreaks in wildlife rescue centers in primate range states where MPXV occurs. Control measures should include quarantining affected animals, limiting human contacts, surveillance of humans and animals, use of personal protective equipment, and regular decontamination of enclosures.</p

Socializing One Health: an innovative strategy to investigate social and behavioral risks of emerging viral threats

In an effort to strengthen global capacity to prevent, detect, and control infectious diseases in animals and people, the United States Agency for International Development’s (USAID) Emerging Pandemic Threats (EPT) PREDICT project funded development of regional, national, and local One Health capacities for early disease detection, rapid response, disease control, and risk reduction. From the outset, the EPT approach was inclusive of social science research methods designed to understand the contexts and behaviors of communities living and working at human-animal-environment interfaces considered high-risk for virus emergence. Using qualitative and quantitative approaches, PREDICT behavioral research aimed to identify and assess a range of socio-cultural behaviors that could be influential in zoonotic disease emergence, amplification, and transmission. This broad approach to behavioral risk characterization enabled us to identify and characterize human activities that could be linked to the transmission dynamics of new and emerging viruses. This paper provides a discussion of implementation of a social science approach within a zoonotic surveillance framework. We conducted in-depth ethnographic interviews and focus groups to better understand the individual- and community-level knowledge, attitudes, and practices that potentially put participants at risk for zoonotic disease transmission from the animals they live and work with, across 6 interface domains. When we asked highly-exposed individuals (ie. bushmeat hunters, wildlife or guano farmers) about the risk they perceived in their occupational activities, most did not perceive it to be risky, whether because it was normalized by years (or generations) of doing such an activity, or due to lack of information about potential risks. Integrating the social sciences allows investigations of the specific human activities that are hypothesized to drive disease emergence, amplification, and transmission, in order to better substantiate behavioral disease drivers, along with the social dimensions of infection and transmission dynamics. Understanding these dynamics is critical to achieving health security--the protection from threats to health-- which requires investments in both collective and individual health security. Involving behavioral sciences into zoonotic disease surveillance allowed us to push toward fuller community integration and engagement and toward dialogue and implementation of recommendations for disease prevention and improved health security

Studies on human immunodeficiency virus genetic drug resistance and subtype distribution in Northern South Africa

PhD (Microbiology

Genetic Analysis of HIV-1 Integrase Sequences from Treatment Naive Individuals in Northeastern South Africa

Raltegravir, an integrase inhibitor, is not a component of the current South African antiretroviral treatment guidelines, but it could be introduced in the near future as cases of virological failures from current treatment regimens begin to occur. The aim of this study was to analyze the complete HIV integrase gene obtained from individuals at two treatment sites in northeastern South Africa for the presence of Raltegravir associated drug resistant mutations and viral subtypes based on the integrase gene. Examination for mutations against other integrase inhibitors, such as Elvitegravir and Dolutegravir, was also done. Viruses from 127 treatment naive individuals were analyzed. Genetic drug resistance mutations were determined using the Stanford HIV Drug Resistance Interpretation program and the International AIDS society-USA guidelines. Viral subtyping was done by phylogenetic analysis, and recombinants were determined using the REGA, jpHMM and RIP tools. No major resistance mutations were detected. However, 7% of the sequences had minor mutations and polymorphisms. The majority (99%) of the viruses were HIV-1 C. Recombination analysis showed that the polymerase gene of one virus was likely composed of HIV-1 subtype A1 and C sequences. The present study indicates that Raltegravir, Elvitegravir and Dolutegravir resistant mutations may be absent in the study communities and further indicates the presence of recombinant viruses in northeastern South Africa