Challenges faced by the HIV testing system in low- and middle-income countries

Introduction: Determining the HIV status of some individuals remains challenging due to multidimensional factors such as flaws in diagnostic systems, technological challenges, and viral diversity. This report pinpoints challenges faced by the HIV testing system in Cameroon. Case presentation: A 53-year-old male received a positive HIV result by a rapid testing algorithm in July 2016. Not convinced of his HIV status, he requested additional tests. In February 2017, he received a positive result using ImmunoComb® II HIV 1 & 2 BiSpot and Roche cobas electrochemiluminescence assays. A sample sent to France in April 2017 was positive on the Bio-Rad GenScreen™ HIV 1/2, but serotyping was indeterminate, and viral load was < 20 copies/mL. The Roche electrochemiluminescence immunoassay and INNO-LIA HIV I/II Score were negative for samples collected in 2018. A sample collected in July 2019 and tested with VIDAS® HIV Duo Ultra enzyme-linked fluorescent assay and Geenius™ HIV 1/2 Confirmatory Assay was positive, but negative with Western blot; CD4 count was 1380 cells/mm3 and HIV proviral DNA tested in France was 'target-not-detected'. Some rapid tests were still positive in 2020 and 2021. Serotyping remained indeterminate, and viral load was 'target-not-detected'. There were no self-reported exposure to HIV risk factors, and his wife was HIV-seronegative.Management and outcome: Given that the patient remained asymptomatic with no evidence of viral replication, no antiretroviral therapy was initiated. Conclusion: This case highlights the struggles faced by some individuals in confirming their HIV status and the need to update existing technologies and develop an algorithm for managing exceptional cases.

Technological potential of under-utilized starches from eight varieties of legumes grown in Cameroon / Potencial tecnológico de amidos subutilizados de oito variedades de leguminosas cultivadas nos Camarões

Abstract Starch samples from eight legumes cultivars instar of one variety of Vigna unguiculata L. (Cowpea), one variety of Vigna subterrenea V. (Bambara groundnut) and six varieties of Phaseolus vulgaris L. (Common bean), grown in Cameroon were isolated, and their physicochemical and pasting properties were evaluated. The objectives of the study were to investigate the starch properties and processing characteristics of different bean varieties, and to establish the basic foundation of improving the functionality of beans and their starch grown in the region. The result revealed significant differences amongst the properties of the starches. The swelling power of the legume starch isolates put them in the category of highly restricted-swelling starch. This characteristic is desirable for the manufacture of value-added products such as noodles and composite blends with cereals. The pasting properties were determined using a rapid visco analyzer, and various legumes bean starches exhibited different pasting profiles. The high breakdown viscosity (BV) was founded for Cowpea and Bambara groundnut and confirmed their low. ability to resist heat and shear stress when compared to Common bean varieties studies. The factors which influence the pasting characteristics resulting to decrease in peak viscosity (PV), trough viscosity (TV) and final viscosity (FV) of starch are attributed to the interaction of starch with the protein, fat, etc. which depended to their variety.

Resumo Foram isoladas amostras de amido de oito cultivares de leguminosas ínstar de uma variedade de Vigna unguiculata L. (feijão caupi), uma variedade de Vigna subterrenea V. (amendoim Bambara) e seis variedades de Phaseolus vulgaris L. (feijão comum), cultivadas nos Camarões, e suas propriedades físico-químicas e de pasta foram avaliadas. Os objetivos do estudo foram investigar as propriedades do amido e as características de processamento de diferentes variedades de feijão e estabelecer as bases básicas para melhorar a funcionalidade do feijão e do amido cultivado na região. O resultado revelou diferenças significativas entre as propriedades dos amidos. O poder de inchamento dos isolados de amido de leguminosas os coloca na categoria de amido com inchamento altamente restrito. Esta característica é desejável para o fabrico de produtos de valor acrescentado, tais como macarrão e misturas compósitas com cereais. As propriedades de pasta foram determinadas usando um analisador rápido de visco, e vários amidos de feijão leguminosos exibiram diferentes perfis de pasta. A alta BV foi fundada para o amendoim Cowpea e Bambara e confirmou sua baixa. capacidade de resistir ao calor e tensão de cisalhamento quando comparado com estudos de variedades de feijão. Os fatores que influenciam as características colantes resultantes da diminuição do pico de viscosidade (PV), da viscosidade mínima (TV) e da viscosidade final (FV) do amido são atribuídos à interação do amido com a proteína, gordura, etc., que dependem da sua variedade.

Low seroprevalence of Zika virus in Cameroonian blood donors

Abstract A Zika virus seroepidemiology study was performed in 1084 blood donors collected from August to October 2015 in six sites of Cameroon representing a large panel of eco-environments. Samples were tested using an anti-NS1 IgG ELISA detection kit and positives were further confirmed by seroneutralization. The observed global seroprevalence was low (around 5%, peaking at 10% and 7.7% in Douala and Bertoua, respectively) with risk factors associated with seropositivity pointing to the existence of a local (peri-)sylvatic cycle of transmission. These results call attention to the potential introduction and subsequent spread in African urban areas of Asian genotype Zika virus currently circulating in the Americas and adapted to transmission by peri-domestic mosquitoes. They should leverage reinforced surveillance efforts in Africa.

Technological potential of under-utilized starches from eight varieties of legumes grown in Cameroon

Abstract Starch samples from eight legumes cultivars instar of one variety of Vigna unguiculata L. (Cowpea), one variety of Vigna subterrenea V. (Bambara groundnut) and six varieties of Phaseolus vulgaris L. (Common bean), grown in Cameroon were isolated, and their physicochemical and pasting properties were evaluated. The objectives of the study were to investigate the starch properties and processing characteristics of different bean varieties, and to establish the basic foundation of improving the functionality of beans and their starch grown in the region. The result revealed significant differences amongst the properties of the starches. The swelling power of the legume starch isolates put them in the category of highly restricted-swelling starch. This characteristic is desirable for the manufacture of value-added products such as noodles and composite blends with cereals. The pasting properties were determined using a rapid visco analyzer, and various legumes bean starches exhibited different pasting profiles. The high breakdown viscosity (BV) was founded for Cowpea and Bambara groundnut and confirmed their low. ability to resist heat and shear stress when compared to Common bean varieties studies. The factors which influence the pasting characteristics resulting to decrease in peak viscosity (PV), trough viscosity (TV) and final viscosity (FV) of starch are attributed to the interaction of starch with the protein, fat, etc. which depended to their variety.

Resumo Foram isoladas amostras de amido de oito cultivares de leguminosas ínstar de uma variedade de Vigna unguiculata L. (feijão caupi), uma variedade de Vigna subterrenea V. (amendoim Bambara) e seis variedades de Phaseolus vulgaris L. (feijão comum), cultivadas nos Camarões, e suas propriedades físico-químicas e de pasta foram avaliadas. Os objetivos do estudo foram investigar as propriedades do amido e as características de processamento de diferentes variedades de feijão e estabelecer as bases básicas para melhorar a funcionalidade do feijão e do amido cultivado na região. O resultado revelou diferenças significativas entre as propriedades dos amidos. O poder de inchamento dos isolados de amido de leguminosas os coloca na categoria de amido com inchamento altamente restrito. Esta característica é desejável para o fabrico de produtos de valor acrescentado, tais como macarrão e misturas compósitas com cereais. As propriedades de pasta foram determinadas usando um analisador rápido de visco, e vários amidos de feijão leguminosos exibiram diferentes perfis de pasta. A alta BV foi fundada para o amendoim Cowpea e Bambara e confirmou sua baixa. capacidade de resistir ao calor e tensão de cisalhamento quando comparado com estudos de variedades de feijão. Os fatores que influenciam as características colantes resultantes da diminuição do pico de viscosidade (PV), da viscosidade mínima (TV) e da viscosidade final (FV) do amido são atribuídos à interação do amido com a proteína, gordura, etc., que dependem da sua variedade.

First Insight into the Current Prevalence of Bovine Tuberculosis in Cattle Slaughtered in Cameroon: the Case of Main Abattoirs of Yaoundé and Douala.

Aim: The aim of this study was to evaluate the current prevalence of bovine tuberculosis at Yaoundé and Douala abattoirs. Study Design: Many investigations confirmed that bovine tuberculosis is prevalent in cattle destined for consumption in Cameroon but the magnitude and the distribution of animal tuberculosis in the country are unknown. Place and Duration of Study: Sampling was made during routine meat inspection, in the Yaoundé and Douala abattoirs located in the Central and Littoral regions of Cameroon respectively. Sampling was successively carried out from November 2010 to April 2011. Sample processing (culture, acid-fast staining and spoligotyping) was made at Mycobacteriology Reference Laboratory in Centre Pasteur of Cameroon. Methods: About 16,316 slaughtered cattle, were successively inspected for tuberculosis during this study. Among them 9,127 and 7,189 were slaughtered in Yaoundé and Douala abattoirs respectively. Evidence of pathology was supported by postmortem examination of carcasses using visual examination and palpation of lungs, livers, hearts, internal bodies and lymph nodes. The prevalence was calculated as the number of cattle with suspected TB lesions divided by the number of cattle examined at post mortem within the specified period. Ziehl-Neelsen staining, culture on solid medium and spoligotyping were made to identify acid-fast Bacilli and Mycobacterium bovis. Results: The overall apparent prevalence of bovine tuberculosis based on suggestive macroscopic lesions induced by tuberculosis was 1.03%. This prevalence was split to 0.81% and 1.3% in Yaoundé and Douala abattoirs respectively. Mycobacterium bovis accounted for 47.62% of the tuberculous lesions and its prevalence was 0.49%. Conclusion: This result show that bovine tuberculosis is still prevalent in cattle destined for human consumption in Cameroon and highlighted the contribution of M. bovis as the leading cause of bovine tuberculosis in Cameroon.

Clinical and Microbiological Assessment of Trachoma in the Kolofata Health District, Far North Region, Cameroon

Background and aims: Trachoma is a sight-threatening process triggered by the infection of the conjunctiva with <i>Chlamydiae</i>. Blindness associated with trachoma was reported in Sahelian areas of Cameroon. However, data on the prevalence of this neglected infection in the Far North Region are not available. The aim of this study was a) to assess clinical trachoma and b) to detect <i>Chlamydia</i> in the conjunctiva of trachomatous populations living in the Far North Regions of Cameroon.Methods: A total of 2,423 randomly selected children (1–10 years) and 1,590 women over 14 from randomly selected villages from the Kolofata Health District (115,000 inhabitants) were included in a cross-sectional study in February 2009. Trained staff examined and obtained conjunctival swabs from trachomatous subjects. DNA was extracted and amplified to detect <i>Chlamydia</i> DNA by real-time PCR. The quality of sampling was assessed by quantifying the number of epithelial cells.Results: Children (2,397 or 98.9% of the predicted number) and women (1,543; 97.0%) were examined. The prevalence of follicular trachoma (TF) in children was 21% (95% CI 17.8–24.5) and of intense inflammatory trachoma (TI) 5.2% (95% CI 3.6–7.3). Among the women, trichiasis (TT) was observed in 3.4% (95% CI 2.4–4.7), corneal opacities (CO) in 1.4% (95% CI 0.8–2.3) and trachoma-related blindness in 0.9% (95% CI 0.4–1.8). Conditions related to income, illiteracy, latrines, water supply and animals wandering close to dwellings were similar in all the villages. PCR was positive in 35% of children with active trachoma and in 6% of adult females presenting TT and/or related corneal opacities.Conclusion: The prevalence of trachoma and the severe trachoma <i>sequelae</i> found during this survey underline the urgent need to implement efficient blindness prevention interventions to improve the visual future of the people in the Sahelian region.