BackgroundMalaria in Cameroon is due to infections by Plasmodium falciparum and, to a lesser extent, Plasmodium malariae and Plasmodium ovale, but rarely Plasmodium vivax. A recent report suggested “Plasmodium vivax–like” infections around the study area that remained unconfirmed. Therefore, molecular and antigenic typing was used to investigate the prevalence of P. vivax and Duffy in asymptomatic adults resident in Bolifamba.MethodsA cross-sectional study was conducted from July 2008 to October 2009. The status of all parasite species was determined by nested PCR in 269 blood samples collected. The P. falciparum and P. vivax anti-MSP/CSP antibody status of each subject was also determined qualitatively by a rapid card assay. Parasite DNA was extracted from a sample infected with three parasite species, purified and sequenced. The Duffy antigen status of 12 subjects infected with P. vivax was also determined by sequencing. In silico web-based tools were used to analyse sequence data for similarities and matches to reference sequences in public DNA databases.ResultsThe overall malaria parasite prevalence in 269 individuals was 32.3% (87) as determined by PCR. Remarkably, 14.9% (13/87) of infections were caused either exclusively or concomitantly by P. vivax, established both by PCR and microscopic examination of blood smears, in individuals both positive (50%, 6/12) and negative (50%, 6/12) for the Duffy receptor. A triple infection by P. falciparum, P. vivax and P. malariae, was detected in one infected individual. Anti-MSP/CSP antibodies were detected in 72.1% (194/269) of samples, indicating high and continuous exposure to infection through mosquito bites.DiscussionThese data provide the first molecular evidence of P. vivax in Duffy positive and negative Cameroonians and suggest that there may be a significant prevalence of P. vivax infection than expected in the study area. Whether the P. vivax cases were imported or due to expansion of a founder effect was not investigated. Notwithstanding, the presence of P. vivax may complicate control efforts if these parasites become hypnozoitic or latent as the liver stage.ConclusionsThese data strongly suggest that P. vivax is endemic to the south-west region of Cameroon and should be taken into account when designing malaria control strategies.

BackgroundPodoconiosis is a non-filarial elephantiasis, which causes massive swelling of the lower legs. It was identified as a neglected tropical disease by WHO in 2011. Understanding of the geographical distribution of the disease is incomplete. As part of a global mapping of podoconiosis, this study was conducted in Cameroon to map the distribution of the disease. This mapping work will help to generate data on the geographical distribution of podoconiosis in Cameroon and contribute to the global atlas of podoconiosis.MethodsWe used a multi‐stage sampling design with stratification of the country by environmental risk of podoconiosis. We sampled 76 villages from 40 health districts from the ten Regions of Cameroon. All individuals of 15-years old or older in the village were surveyed house-to-house and screened for lymphedema. A clinical algorithm was used to reliably diagnose podoconiosis, excluding filarial-associated lymphedema. Individuals with lymphoedema were tested for circulating Wuchereria bancrofti antigen and specific IgG4 using the Alere Filariasis Test Strips (FTS) test and the Standard Diagnostics (SD) BIOLINE lymphatic filariasis IgG4 test (Wb123) respectively, in addition to thick blood films. Presence of DNA specific to W. bancrofti was checked on night blood using a qPCR technique.Principal findingsOverall, 10,178 individuals from 4,603 households participated in the study. In total, 83 individuals with lymphedema were identified. Of the 83 individuals with lymphedema, two were found to be FTS positive and all were negative using the Wb123 test. No microfilaria of W. bancrofti were found in the night blood of any individual with clinical lymphedema. None were found to be positive for W. bancrofti using qPCR. Of the two FTS positive cases, one was positive for Mansonella perstans DNA, while the other harbored Loa loa microfilaria. Overall, 52 people with podoconiosis were identified after applying the clinical algorithm. The overall prevalence of podoconiosis was found to be 0.5% (95% [confidence interval] CI; 0.4–0.7). At least one case of podoconiosis was found in every region of Cameroon except the two surveyed villages in Adamawa. Of the 40 health districts surveyed, 17 districts had no cases of podoconiosis; in 15 districts, mean prevalence was between 0.2% and 1.0%; and in the remaining eight, mean prevalence was between 1.2% and 2.7%.ConclusionsOur investigation has demonstrated low prevalence but almost nationwide distribution of podoconiosis in Cameroon. Designing a podoconiosis control program is a vital next step. A health system response to the burden of podoconiosis is important, through case surveillance and morbidity management services.

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Birds are crucial in maintaining the balance of many ecosystems and provide various ecological services. Understanding their sensitivity to human disturbances should be prioritized in understudy areas for effective conservation practices. Using mist nets, this study characterized mostly understory bird communities (insectivorous, frugivorous, granivorous, and nectarivorous birds) in three habitat types (pristine forest, selectively logged forest, and young oil palm plantation) in the Talangaye rainforest, Southwest Cameroon. A total of 845 birds belonging to 27 families and 85 species were recorded in the three habitats after 294 h of mist netting. Overall, the mist-netted community was largely dominated by insectivores, followed by frugivores, nectarivores, granivores, and carnivores. Although mean species richness, abundance, and Simpson diversity index did not vary significantly among habitat types, mean species abundance and diversity index decreased in selectively logged forest and young oil palm plantation and species richness increased in both habitats. The species richness, abundance, and diversity index for insectivorous and frugivorous birds were lowest in the young oil palm plantations. For granivores, species richness and abundance increased following selective logging and the establishment of oil palm plantation. The highest mean species richness and diversity index in nectarivores were recorded in the young oil palm plantations. The study showed that selective logging and establishment of oil palm plantation had variable effects on the bird communities in the Talangaye rainforest. Also, the frugivorous birds appeared to be more sensitive to both types of disturbances, while the insectivores were more sensitive to habitat loss/conversion.

The influence of the genetic diversity of Plasmodium falciparum infection on the clinical presentation of human malaria was investigated in rural Bolifamba, Cameroon. Parasite DNA was obtained from the blood of 208 children (aged 1-15 years) with malarial infection. The prevalences of anaemia and symptomatic and asymptomatic malaria among these children were 57.7%, 51.4% and 48.6%, respectively. The frequencies of parasites carrying each of the block-2 allelic variants (MAD20, K1 and RO33) of merozoite surface protein 1 (MSP1) were compared among the symptomatic and asymptomatic cases of malaria, the anaemic and non-anaemic subjects, and in various age groupings. Although all three allelic variants were found in Bolifamba, 32.7% of the children investigated were co-infected with parasites carrying the RO33 and K1 variants. There was a significant difference in the prevalence of each MSP1 allelic variant both between age-groups and between the various categories of anaemia considered (P<0.0001 for each), with the highest number of alleles occurring in the children with severe anaemia. The combination of RO33/K1 co-infection and anaemia was detected in most (57.7%) of the children aged 3-<6 years. The RO33/K1 co-infection was also strongly associated with both fever and high levels of parasitaemia (P<0.0001 for each). Although the children of Bolifamba are exposed to all three allelic variants of MSP1, which occur either singly or in varying combinations in the infected children, RO33/K1 co-infections are particularly associated with fever and this association appears independent of age and parasite density. The preliminary data presented here should facilitate the design of future research towards the development and testing of malaria candidate vaccines in the study area.

Background Ivermectin is an excellent microfilaricide against Onchocerca volvulus. However, in some regions, long term use of ivermectin has resulted in sub-optimal responses to the treatment. More data to properly document the phenomenon in various contexts of ivermectin mass drug administration (IVM-MDA) is needed. Also, there is a need to accurately monitor a possible repopulation of skin by microfilariae following treatment. Skin snip microscopy is known to have a low sensitivity in individuals with light infections, which can be the case following treatment. This study was designed with two complementary objectives: (i) to assess the susceptibility of O. volvulus microfilariae to ivermectin in two areas undergoing IVM-MDA for different lengths of time, and (ii) to document the repopulation of skin by the O. volvulus microfilariae following treatment, using 3 independent diagnostic techniques. Method Identified microfilaridermic individuals were treated with ivermectin and re-examined after 1, 3, and 6 months using microscopy, actin real-time PCR (actin-qPCR) and O-150 LAMP assays. Susceptibility to ivermectin and trends in detecting reappearance of skin microfilariae were determined using three techniques. Microscopy was used as an imperfect gold standard to determine the performance of actin-qPCR and LAMP. Results In Bafia with over 20 years of IVM-MDA, 11/51 (21.6%) direct observe treated microfilaridemic participants were still positive for skin microfilariae after 1 month. In Melong, with 10 years of IVM-MDA, 2/29 (6.9%) treated participants were still positive. The microfilarial density reduction per skin biopsy within one month following treatment was significantly lower in participants from Bafia. In both study sites, the molecular techniques detected higher proportions of infected individuals than microscopy at all monitoring time points. LAMP demonstrated the highest levels of sensitivity and real-time PCR was found to have the highest specificity. Conclusion Patterns in skin mirofilariae clearance and repopulation were established. O. volvulus worms from Bafia with higher number of annual MDA displayed a lower clearance and higher repopulation rate after treatment with ivermectin. Molecular assays displayed higher sensitivity in monitoring O. volvulus microfilaridemia within six months following treatment.

Background Urinary tract infections (UTIs) are the second most frequent infections after respiratory tract infections that affect humans, with over 150 million cases per year. The anatomy of the female urinary tract predisposes them to UTIs than men. More so, physiological and hormonal changes during pregnancy put pregnant woman at risk of UTIs. Untreated UTI(s) in pregnancy can be detrimental to both the mother and child causing preterm labour, low birth weight and pyelonephritis. The situation is worrisome because the infection can be asymptomatic. This study investigated the prevalence and risk factors for UTIs, diagnostic potential of dipstick analyses and antimicrobial susceptibility of uropathogens from pregnant women attending ANC in some Integrated Health Centers (IHCs) in Buea Health District (BHD). Methods A structured questionnaire was administered to consenting pregnant women at participating IHCs to collect data on demographic characteristics, risk factors and symptoms of UTI. Urine samples were collected for dipstick analysis and culture. Antibiograms were performed on the isolates by the disc diffusion method. A bivariate analysis was performed to investigate the association of the risk factors to UTI. Chi square (χ2) test, odds ratios with corresponding 95% confidence intervals were used to compare statistics and test for associations at a significant level of p ≤ 0.05. Results Of the 287 participants recruited, 89(31%) were positive for UTI. There were 150 women with no symptoms of which 43(28.7%) were positive for UTI. E. coli was the most frequent (43.2%) of the organisms implicated in bacteriuria. There was no significant association between the risk factors studied and UTI. Isolates were most sensitive to ciprofloxacin (73.5%) and gentamycin (73.5%) and resistant to ceftriaxone (70.6%) and tetracycline (64.7%). Nitrite test was highly specific (100%) for the diagnosis of UTI while leucocyte esterase was more sensitive (48.3%) than specific (44.9%). Conclusions The prevalence of UTI in BHD was high. In conformity with previous findings in same area, there were no risk factors associated with UTI. We recommended a longitudinal study with a larger sample size to follow up the women to term in order to determine the gravity of this infection on pregnancy outcomes.

Background. The genetic variability of the artemisinin resistance (AR) molecular marker