Population genetics of Trypanosoma brucei circulating in Glossina palpalis palpalis and domestic animals of the Fontem sleeping sickness focus of Cameroon

BACKGROUND: Human African Trypanosomiasis is still a public health threat in Cameroon. To assess Trypanosoma brucei strains circulating in the Fontem sleeping sickness focus, we conducted a genetic structure study using microsatellites to assess genotypes circulating in both tsetse flies and domestic animals. METHOD: For this study, pyramidal traps were set up and 2695 tsetse flies were collected and 1535 (57%) living flies were dissected and their mid-guts collected. Furthermore, blood samples were collected from 397 domestic animals (pigs, goats, sheep and dogs). DNA was extracted from midguts and blood samples, and specific primers were used to identify trypanosomes of the subgenus Trypanozoon. All positive samples were genetically characterized with seven microsatellite markers. RESULTS: Seventy five (4.7%) midguts of tsetse flies and 140 (35.2%) domestic animals were found infected by trypanosomes of the subgenus Trypanozoon. The genetic characterization of 215 Trypanozoon positive samples (75 from tsetse and 140 from animals) revealed a genetic diversity between Trypanosoma brucei circulating in tsetse and domestic animals. Of these positive samples, 87 (40.5%) single infections were used here to investigate the population genetics of Trypanosoma brucei circulating in tsetse and domestic animals. The dendrogram illustrating the genetic similarities between Trypanosoma brucei genotypes was subdivided into four clusters. The samples from tsetse belonged to the same cluster whereas the samples from domestic animals and espcially pigs were distributed in the four clusters. CONCLUSION: Pigs appeared as the animal species harboring the highest number of different Trypanosoma brucei strains. They may play an important role in the propagation of different genotypes. The F(ST) values revealed a sub structuration of Trypanosoma brucei according to hosts and sometimes villages. The data obtained from this study may have considerable importance for the understanding of the transmission and the spread of specific genotypes of Trypanosoma brucei

Human African Trypanosomiasis Transmission, Kinshasa, Democratic Republic of Congo

To investigate the epidemiology of human African trypanosomiasis (sleeping sickness) in Kinshasa, Democratic Republic of Congo, 2 entomologic surveys were conducted in 2005. Trypanosoma brucei gambiense and human-blood meals were found in tsetse fly midguts, which suggested active disease transmission. Vector control should be used to improve human African trypanosomiasis control efforts

Post-partum trend in blood pressure levels, renal function and proteinuria in women with severe preeclampsia and eclampsia in Sub-Saharan Africa: A 6-months cohort study

BACKGROUND: Preeclampsia and eclampsia, which are the most frequent hypertensive disorders in pregnancy, are associated with renal involvements. We aimed to assess the time trend in blood pressure levels, renal function and proteinuria after delivery, and investigate their determinants in Cameroonian women with severe preeclampsia and eclampsia. METHODS: This was a prospective cohort study involving 54 women with severe preeclampsia and eclampsia, conducted between July 2010 and February 2012 at the central maternity unit of the Yaounde Central Hospital. Clinical and laboratory parameters were recorded from day-1 to 6months after delivery. Mixed-linear and logistic regression models were used to relate baseline and within follow-up levels of covariates, with changes in blood pressure levels, renal function and proteinuria, as well as persisting hypertension, renal failure and proteinuria. RESULTS: During follow-up, a significant improvement was observed in blood pressure, renal function and proteinuria (all p<0.002). Thirteen (24.1%) patients with renal failure at delivery recovered completely within six weeks. Twenty-six (48.1%), 17 (31.5%) and 1 (1.8%) patients had persisting proteinuria at 6weeks, 3months and 6months post-delivery, respectively. Corresponding figures for persisting hypertension were 23 (42.6%), 15 (27.8%) and 8 (14.8%). Advanced age, higher body mass index, low gestational age at delivery, low fetal birth weight, and proteinuria at delivery were the main risk factors for persisting hypertension at 3months, meanwhile low fetal birth weight, severe preeclampsia and proteinuria at delivery were correlated with persisting proteinuria at 3months. Advanced age and higher body mass index were the only determinants of the composite outcome of persisting hypertension or proteinuria at three and six months. CONCLUSION: Hypertension and proteinuria are very common beyond the postpartum period in Cameroonian women with severe preeclampsia and eclampsia. Long-term follow-up of these women will help preventing and controlling related complications

Field Evaluation of Calypte’s AWARE™ Blood Serum Plasma (BSP) and Oral Mucosal Transudate (OMT) Rapid Tests for Detecting Antibodies to HIV-1 and 2 in Plasma and Oral Fluid

As programs to prevent and care for HIV-infected persons are scaled-up in Africa, there is the need for continuous evaluation of the performance of test kits that could best support these programs. The present study evaluated the sensitivity, specificity, ease of use, and cost of AWARE ™ Blood Serum Plasma (BSP) and Oral Mucosal Transudate (OMT) Rapid HIV-1/2 test kits using real-time and archived samples of HIV-infected persons from Cameroon. Matched whole blood and OMT specimens were collected prospectively from HIV-positive and HIV-negative persons from different regions of Cameroon and tested using the AWARE ™ BSP and OMT test kits, respectively. These results were compared to the gold standard that included a combination of Determine HIV-1/2 and Enzygnost HIV-1/2. The BSP Rapid test kit was further evaluated using well characterized panels of HIV-2 and HIV-1 group O samples. Cost and end-user analysis of the OMT test kit was done by comparing its actual cost, consumables, safety, bench time and manipulation with other test kits. Of the 732 matched samples, 412 (56.3%) and 320 (43.7%) were from females and males, respectively. Of these samples, 23 (3.1%) gave discordant results between Determine HIV-1/2 and Enzygnost HIV1/2 and were excluded from the analysis. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the AWARE™ BSP were 100%. The AWARE™ OMT had 98.8% sensitivity, 98.9% specificity, 98.0% PPV and 99.4% NPV. The results of a well-characterized archived panel of HIV-2 (n=7) and HIV-1 group O (n=3) samples using the AWARE™ BSP Rapid test kit gave 100% concordance. Total per patient cost of the AWARE OMT rapid test kit was US$4.72 compared to a mean cost of US$7.33 ± 0.11 for the other test kits. Both the AWARE™ BSP and OMT Rapid test kits demonstrated high sensitivities and specificities on all samples tested and were well adapted for use in resource-constrained settings with high HIV heterogeneity such as Cameroon. The AWARE ™ HIV-1/2 OMT Rapid test kit appears to be the cheapest, safest and easiest to use compared with other available test kits

Whole blood pathogen reduction technology and blood safety in sub-Saharan Africa: A systematic review with regional discussion

Background: Despite vast improvements in transfusion services in sub-Saharan Africa over the last decade, there remain serious concerns on the safety and adequacy of the blood supply across the region. Objective: This review paper ascertains the role of pathogen reduction technology (PRT) in improving blood safety and supply adequacy in the region. Method: The state of blood safety in sub-Saharan Africa was reviewed. Meetings, seminars and correspondence were undertaken with key clinicians, scientists and professional bodies in the region, including the World Health Organization’s Regional Office for Africa, to examine the suitability of PRT for improving the safety of whole blood transfusion, a prevalent transfusion format in the region. Results: Existing literature suggests that combining PRT with current blood safety measures (such as serology) would improve the safety and adequacy of the blood supply for transfusions in sub-Saharan Africa. This was echoed by the findings of the stakeholder meetings. Conclusion: Following a detailed appraisal of two leading PRT systems, the Mirasol® PRT System and the Cerus S-303 System, we suggest that companies conduct comprehensive toxicological evaluation of the agents used for PRT and publish this in the scientific literature. We also recommend that the safety and efficacy of these technologies should be established in a randomised clinical trial conducted in sub-Saharan Africa

Microsporidian Infection Is Prevalent in Healthy People in Cameroon▿

Most studies of opportunistic infections focus on those with weak immune systems, such as human immunodeficiency virus (HIV)/AIDS patients and children. However, there is a lack of information on these infectious agents in healthy people worldwide. In the present study, stool samples from both HIV patients and healthy people were examined to begin filling in this serious gap in the understanding of human microsporidiosis, particularly the enteric parasite Enterocytozoon bieneusi. Specimens were obtained from 191 individuals living in Yaoundé, the capital city of Cameroon, in sub-Sahara Africa, including 28 HIV-positive patients who also had tuberculosis (TB). E. bieneusi prevalence was 35.7% among the HIV+ TB patients, whereas it was only 24.0% among 25 HIV− TB patients in the same hospital. Unexpectedly, the prevalence (67.5%) of microsporidiosis was found to be even higher for 126 immunocompetent individuals than for those with TB (healthy people compared to HIV+ TB and HIV− TB patients; P < 0.001). The immunocompetent group included people ranging from 2 to 70 years of age living in four different neighborhoods in Yaoundé. The highest prevalence (81.5%) was among teenagers, and the highest mean infection score (+2.5) was among children. Additional studies of immunocompetent people in other parts of Cameroon, as well as in other countries, are needed to better understand microsporidiosis epidemiology. There is still much more to be learned about the natural history of microsporidia, the pathogenicity of different strains, and the role of enteric microsporidia as opportunistic infections in immunodeficient people

Lipid peroxidation and total cholesterol in HAART-naïve patients infected with circulating recombinant forms of human immunodeficiency virus type-1 in Cameroon.

BackgroundHIV infection has commonly been found to affect lipid profile and antioxidant defense.ObjectivesTo determine the effects of Human Immunodeficiency Virus (HIV) infection and viral subtype on patient's cholesterol and oxidative stress markers, and determine whether in the absence of Highly Active Antiretroviral Therapy (HAART), these biochemical parameters could be useful in patient's management and monitoring disease progression in Cameroon. For this purpose, we measured total cholesterol (TC), LDL cholesterol (LDLC), HDL cholesterol (HDLC), total antioxidant ability (TAA), lipid peroxidation indices (LPI), and malondialdehyde (MDA) in HIV negative persons and HIV positive HAART-naïve patients infected with HIV-1 group M subtypes.MethodsWe measured serum TC, LDLC, HDLC, plasma MDA, and TAA concentrations, and calculated LPI indices in 151 HIV-positive HAART-naïve patients and 134 seronegative controls. We also performed gene sequence analysis on samples from 30 patients to determine the effect of viral genotypes on these biochemical parameters. We also determined the correlation between CD4 cell count and the above biochemical parameters.ResultsWe obtained the following controls/patients values for TC (1.96±0.54/1. 12±0. 48 g/l), LDLC (0. 67±0. 46/0. 43±0. 36 g/l), HDLC (105. 51±28. 10/46. 54±23. 36 mg/dl) TAA (0. 63±0. 17/0. 16±0. 16 mM), MDA (0. 20±0. 07/0. 41±0. 10 µM) and LPI (0. 34±0. 14/26. 02±74. 40). In each case, the difference between the controls and patients was statistically significant (pConclusionThese results show that HIV infection in Cameroon is associated with significant decrease in TAA, LDLC, HDLC and TC, and increased MDA concentration and LPI indices which seem to be linked to the severity of HIV infection as assessed by CD4 cell count. The data suggests increased oxidative stress and lipid peroxidation in HIV-infected patients in Cameroon, and an influence of CRFs on TC and MDA levels