Molecular epidemiology and phylogeography of Schistosoma mansoni around Lake Victoria

Parasitology ◽  
2010 ◽  
Vol 137 (13) ◽  
pp. 1937-1949 ◽  
Author(s):  
C. J. STANDLEY ◽  
N. B. KABATEREINE ◽  
C. N. LANGE ◽  
N. J. S. LWAMBO ◽  
J. R. STOTHARD
Keyword(s):  
Population Genetics ◽  
Schistosoma Mansoni ◽  
Molecular Epidemiology ◽  
Lake Victoria ◽  
Public Health Problem ◽  
Human Migration ◽  
Sub Saharan Africa ◽  
Major Public Health Problem ◽  
Sub Saharan ◽  
Coi Sequences

SUMMARYIntestinal schistosomiasis continues to be a major public health problem in sub-Saharan Africa, and is endemic in communities around Lake Victoria. Interest is growing in the molecular evolution and population genetic structure of Schistosoma mansoni and we describe a detailed analysis of the molecular epidemiology and phylogeography of S. mansoni from Lake Victoria. In total, 388 cytochrome oxidase 1 (COI) sequences were obtained from 25 sites along the Ugandan, Tanzanian and Kenyan shorelines of Lake Victoria, and 122 unique barcodes were identified; 9 corresponded to previously discovered barcodes from Lakes Victoria and Albert. A subset of the data, composed of COI sequences from miracidia from 10 individual children, was used for population genetics analyses; these results were corroborated by microsatellite analysis of 4 isolates of lab-passaged adult worms. Overall, 12 barcodes were found to be shared across all 3 countries, whereas the majority occurred singly and were locally restricted. The population genetics analyses were in agreement in revealing high diversity at the level of the human host and negligible population structuring by location. The lack of correlation between genetic distance and geographical distance in these data may be attributed to the confounding influence of high intra-individual diversity as well as human migration between communities.

A multi-state spatio-temporal Markov model for categorized incidence of meningitis in sub-Saharan Africa

2012 ◽  
Vol 141 (8) ◽  
pp. 1764-1771 ◽  
Author(s):  
L. AGIER ◽  
M. STANTON ◽  
G. SOGA ◽  
P. J. DIGGLE
Keyword(s):  
Positive Predictive Value ◽  
Predictive Value ◽  
Public Health Problem ◽  
Incidence Rates ◽  
Sub Saharan Africa ◽  
Major Public Health Problem ◽  
Temporal Dependence ◽  
Spatio Temporal ◽  
Sub Saharan ◽  
Annual Scale

SUMMARYMeningococcal meningitis is a major public health problem in the African Belt. Despite the obvious seasonality of epidemics, the factors driving them are still poorly understood. Here, we provide a first attempt to predict epidemics at the spatio-temporal scale required for in-year response, using a purely empirical approach. District-level weekly incidence rates for Niger (1986–2007) were discretized into latent, alert and epidemic states according to pre-specified epidemiological thresholds. We modelled the probabilities of transition between states, accounting for seasonality and spatio-temporal dependence. One-week-ahead predictions for entering the epidemic state were generated with specificity and negative predictive value >99%, sensitivity and positive predictive value >72%. On the annual scale, we predict the first entry of a district into the epidemic state with sensitivity 65·0%, positive predictive value 49·0%, and an average time gained of 4·6 weeks. These results could inform decisions on preparatory actions.

scholarly journals Plasmodium ovale: Parasite and Disease

2005 ◽  
Vol 18 (3) ◽  
pp. 570-581 ◽  
Author(s):  
William E. Collins ◽  
Geoffrey M. Jeffery
Keyword(s):  
Public Health Problem ◽  
Molecular Techniques ◽  
Sub Saharan Africa ◽  
Enzyme Linked Immunosorbent Assay ◽  
Developmental Cycle ◽  
Major Public Health Problem ◽  
Plasmodium Ovale ◽  
Malaria Parasites ◽  
Sub Saharan

SUMMARY Humans are infected by four recognized species of malaria parasites. The last of these to be recognized and described is Plasmodium ovale. Like the other malaria parasites of primates, this parasite is only transmitted via the bites of infected Anopheles mosquitoes. The prepatent period in the human ranges from 12 to 20 days. Some forms in the liver have delayed development, and relapse may occur after periods of up to 4 years after infection. The developmental cycle in the blood lasts approximately 49 h. An examination of records from induced infections indicated that there were an average of 10.3 fever episodes of ≥101°F and 4.5 fever episodes of ≥104°F. Mean maximum parasite levels were 6,944/μl for sporozoite-induced infections and 7,310/μl for trophozoite-induced infections. Exoerythrocytic stages have been demonstrated in the liver of humans, chimpanzees, and Saimiri monkeys following injection of sporozoites. Many different Anopheles species have been shown to be susceptible to infection with P. ovale, including A. gambiae, A. atroparvus, A. dirus, A. freeborni, A. albimanus, A. quadrimaculatus, A. stephensi, A. maculatus, A. subpictus, and A. farauti. An enzyme-linked immunosorbent assay has been developed to detect mosquitoes infected with P. ovale using a monoclonal antibody directed against the circumsporozoite protein. Plasmodium ovale is primarily distributed throughout sub-Saharan Africa. It has also been reported from numerous islands in the western Pacific. In more recent years, there have been reports of its distribution on the Asian mainland. Whether or not it will become a major public health problem there remains to be seen. The diagnosis of P. ovale is based primarily on the characteristics of the blood stages and its differentiation from P. vivax. The sometimes elliptical shape of the infected erythrocyte is often diagnostic when combined with other, subtler differences in morphology. The advent of molecular techniques, primarily PCR, has made diagnostic confirmation possible. The development of techniques for the long-term frozen preservation of malaria parasites has allowed the development diagnostic reference standards for P. ovale. Infections in chimpanzees are used to provide reference and diagnostic material for serologic and molecular studies because this parasite has not been shown to develop in other nonhuman primates, nor has it adapted to in vitro culture. There is no evidence to suggest that P. ovale is closely related phylogenetically to any other of the primate malaria parasites that have been examined.

scholarly journals Seroprevalence of Hepatitis B and C among Healthcare Workers in Dutse Metropolis Jigawa State, Nigeria

2018 ◽  
Author(s):  
N.M. Sani ◽  
I. Bitrus ◽  
A.M. Sarki ◽  
N.S. Mujahid
Keyword(s):  
Health Care ◽  
Hepatitis B ◽  
Health Care Workers ◽  
Healthcare Workers ◽  
Public Health Problem ◽  
Sub Saharan Africa ◽  
Chromatographic Technique ◽  
Major Public Health Problem ◽  
Care Workers ◽  
Sub Saharan

AbstractHepatitis is one of the neglected infectious diseases in sub Saharan Africa and most of the available data is based on blood donors. Health care workers (HCWs) often get infected as a result of their close contact with patients. A cross sectional study was conducted to determine the prevalence of hepatitis B and C among this group of professionals with a view to improving the quality of care to their patients. Hepatitis B and C infections pose a major public health problem worldwide. While infection is highest in the developing world particularly Asia and sub-Saharan Africa, healthcare workers are at higher risk of acquiring blood-borne viral infections, particularly Hepatitis B and C which are mostly asymptomatic. This study was aimed at determining the prevalence of Hepatitis B and C infections and associated risk factors among health care workers in Dutse Metropolis, Jigawa State - Nigeria. A standard rapid immuno-chromatographic technique i.e. rapid ELISA was used to screen all sera for Hepatitis B surface antigen (HBsAg) and Hepatitis C viral antibody (HCVAb) respectively. Strips containing coated antibodies and antigens to HBV and HCV respectively were removed from the foil. Strips were labeled according to samples. Using a separate disposable pipette, 2 drops of the sample (plasma) were added into each test strip and allowed to run across the absorbent pad. Results were read after 15 minutes. The prevalence of HBV and HCV infection in 100 healthcare workers was determined by testing the plasma collected from the clients during their normal checkup using HBsAg and HCVAb test strips. Results were subjected to statistical analysis using chi-square test. The prevalence of HBV among HCWs was 19 out of 100 (19.0%) and that of HCV was 5 out of 100 (5.0%) where in both cases, higher prevalence was observed among female nurses. It was also observed that all HCV positive cases were recorded among nurses only. The study revealed that nurses are at greater risk of contracting HBV and HCV due to their frequent contact with patients. It is therefore recommended that effective vaccination and other infection control measures be encouraged among healthcare workers.

scholarly journals Rasmussen syndrome in a tropical environment: a study of six (6) observations

2021 ◽  
Vol 57 (1) ◽  
Author(s):  
Carlos Othon Guelngar ◽  
Touré Mohamed Lamine ◽  
Barry Mamadou Ciré ◽  
Diakité Mamady ◽  
Konaté Mahadi ◽  
...  
Keyword(s):  
Public Health ◽  
Valproic Acid ◽  
Analytical Study ◽  
Public Health Problem ◽  
Epileptic Seizures ◽  
Sub Saharan Africa ◽  
Major Public Health Problem ◽  
Mental Deterioration ◽  
Rasmussen Syndrome ◽  
Sub Saharan

Abstract Background In sub-Saharan Africa, encephalitis of various etiologies is a major public health problem and Rasmussen syndrome is rarely diagnosed due to under-medicalization. The objective of this study is to describe the clinical and neuroradiological forms, especially since this affection is little known in sub-Saharan Africa as evidenced by the scarcity of publications. Results A retrospective, descriptive and analytical study of six (6) cases of Rasmussen syndrome, shows that it is an unrecognized disease in Africa. Men were more represented with a frequency of 67% with a young age. The clinical picture dominated by 100% seizures, mental deterioration and hemiparesis. The etiology is still questionable, probably autoimmune in our study. Conclusion Rasmussen syndrome accounts for 3% in 219 patients hospitalized for epileptic conditions. This study shows a clinical profile dominated by recurrent epileptic seizures refractory to the drugs Phenobarbital, Valproic Acid and Carbamazepine, the only antiepileptics available in the country. These results are valid for therapeutic and prognostic discussion.

Preterm birth and associated factors among mothers who gave birth in Dire Dawa, Ethiopia

2021 ◽  
Vol 29 (6) ◽  
pp. 338-345
Author(s):  
Alekaw Sema ◽  
Nigus Kassie ◽  
Bezabih Amsalu ◽  
Yalelet Belay ◽  
Alemu Guta ◽  
...  
Keyword(s):  
Preterm Birth ◽  
Associated Factors ◽  
Public Health Problem ◽  
Cross Sectional Study ◽  
Sub Saharan Africa ◽  
Major Public Health Problem ◽  
Cross Sectional ◽  
Eastern Ethiopia ◽  
Dire Dawa ◽  
Sub Saharan

Background The highest rate of preterm birth in the world is in Sub-Saharan Africa and Asia. However, there is limited data in this study area. Therefore, this study aims to assess the prevalence and associated factors of preterm birth in Dire Dawa City, Eastern Ethiopia. Method An institutional-based, cross-sectional study was conducted with 420 respondents. Conclusion Preterm birth is still a major public health problem in Dire Dawa City.

scholarly journals Methylene blue inhibits lumefantrine-resistant Plasmodium berghei

2016 ◽  
Vol 10 (06) ◽  
pp. 635-642 ◽  
Author(s):  
Victor Irungu Mwangi ◽  
Ruth Mwende Mumo ◽  
Daniel Muthui Kiboi ◽  
Sabah Ahmed Omar ◽  
Zipporah Waithera Ng'ang'a ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Combination Therapy ◽  
Large Scale ◽  
Public Health Problem ◽  
Drug Repurposing ◽  
Sub Saharan Africa ◽  
Major Public Health Problem ◽  
Resistant Strains ◽  
Sub Saharan ◽  
Emergence Of Resistance

Introduction: Chemotherapy still is the most effective way to control malaria, a major public health problem in sub-Saharan Africa. The large-scale use of the combination therapy artemether-lumefantrine for malaria treatment in Africa predisposes lumefantrine to emergence of resistance. There is need to identify drugs that can be used as substitutes to lumefantrine for use in combination therapy. Methylene blue, a synthetic anti-methemoglobinemia drug, has been shown to contain antimalarial properties, making it a candidate for drug repurposing. The present study sought to determine antiplasmodial effects of methylene blue against lumefantrine- and pyrimethamine-resistant strains of P. berghei. Methodology: Activity of methylene blue was assessed using the classical four-day test on mice infected with lumefantrine-resistant and pyrimethamine-resistant P. berghei. A dose of 45 mg/kg/day was effective for testing ED90. Parasitemia and mice survival was determined. Results: At 45 mg/kg/day, methylene blue sustained significant parasite inhibition, over 99%, for at least 6 days post-treatment against lumefantrine-resistant and pyrimethamine-resistant P. berghei (p = 0.0086 and p = 0.0191, respectively). No serious adverse effects were observed. Conclusions: Our results indicate that methylene blue at a concentration of 45 mg/kg/day confers over 99% inhibition against lumefantrine- and pyrimethamine-resistant P. berghei for six days. This shows the potential use methylene blue in the development of antimalarials against lumefantrine- and pyrimethamine-resistant parasites.

scholarly journals Evaluation of Vitamin D in Sickle Cell Anaemia Patients at Steady State

2020 ◽  
Vol 1 (2) ◽  
Author(s):  
Umar Aminu Abdullah ◽  
Mohammed Bashir AbdulRahman ◽  
Bello Aminu ◽  
Abubakar Umar Musa ◽  
Isah Balarabe
Keyword(s):  
Vitamin D ◽  
Steady State ◽  
Sickle Cell ◽  
Sickle Cell Anaemia ◽  
Public Health Problem ◽  
Bone Fragility ◽  
Sub Saharan Africa ◽  
Major Public Health Problem ◽  
The Mean ◽  
Sub Saharan

Background: Sickle cell anaemia is a major public health problem in sub-Saharan Africa with high morbidities like bony alterations and bone fragility especially in those with vitamin D deficiency. There is paucity of research data on bone biomarkers in patients with sickle cell anaemia especially in Northern Nigeria. The aim of this study was to evaluate vitamin D in adult sickle cell anaemia patients at steady state. Materials and Methods: Seventy-seven patients with sickle cell anaemia and equal number of apparently healthy matched controls were recruited for the study. Various biochemical parameters of bone metabolism were measured. Data were analysed using IBM SPSS version 23.0. Results: The mean age of SCA adult patients and controls wer

Schistosomes of small mammals from the Lake Victoria Basin, Kenya: new species, familiar species, and implications for schistosomiasis control

Parasitology ◽  
2010 ◽  
Vol 137 (7) ◽  
pp. 1109-1118 ◽  
Author(s):  
B. HANELT ◽  
I. N. MWANGI ◽  
J. M. KINUTHIA ◽  
G. M. MAINA ◽  
L. E. AGOLA ◽  
...  
Keyword(s):  
Schistosoma Mansoni ◽  
Small Mammals ◽  
Lake Victoria ◽  
Sub Saharan Africa ◽  
Lake Victoria Basin ◽  
Murid Rodent ◽  
Schistosomiasis Control ◽  
Wild Mammals ◽  
Sub Saharan ◽  
Reservoir Hosts

SUMMARYRecent schistosomiasis control efforts in sub-Saharan Africa have focused nearly exclusively on treatment of humans with praziquantel. However, the extent to which wild mammals act as reservoirs forSchistosoma mansoniand therefore as sources of renewed transmission following control efforts is poorly understood. With the objective to study the role of small mammals as reservoir hosts, 480 animals belonging to 9 rodent and 1 insectivore species were examined for infection with schistosomes in Kisumu, in the Lake Victoria Basin, Kenya. Animals were collected from 2 sites: near the lakeshore and from Nyabera Marsh draining into the lake. A total of 6·0% of the animals captured, including 5 murid rodent species and 1 species of shrew (Crocidura olivieri) were infected with schistosomes. Four schistosome species were recovered and identified usingcox1 DNA barcoding:S. mansoni,S. bovis,S. rodhainiandS. kisumuensis, the latter of which was recently described from Nyabera Marsh.Schistosoma mansoniandS. rodhainiwere found infecting the same host individual (Lophuromys flavopunctatus), suggesting that this host species could be responsible for the production of hybrid schistosomes found in the area. Although the prevalence ofS. mansoniinfection in these reservoir populations was low (1·5%), given their potentially vast population size, their impact on transmission needs further study. Reservoir hosts could perpetuate snail infections and favour renewed transmission to humans once control programmes have ceased.

scholarly journals Maternal Body Mass Index Is Strongly Associated with Children Z-Scores for Height and BMI

2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Pushpa Lata Tigga ◽  
Jaydip Sen
Keyword(s):  
Body Mass Index ◽  
Body Composition ◽  
Nutritional Status ◽  
Body Mass ◽  
Public Health Problem ◽  
Sub Saharan Africa ◽  
Maternal Body Mass Index ◽  
Major Public Health Problem ◽  
Maternal Body ◽  
Sub Saharan

Introduction. Undernutrition continues to be a major public health problem throughout the developing world, particularly in sub-Saharan Africa and Asia including India. Limited studies suggest associations between maternal body mass index (BMI) and child nutritional status. The present study aims to determine the relationship between maternal BMI and children nutritional status. Methods. The study was conducted among 246 mothers who had given birth to single children (n=246) and belonged to the Proto-Australoid population of North Bengal, India. The anthropometric measurements of height and weight were recorded following standard procedures. Overall body composition was evaluated using BMI. Result. The results showed that overall mean BMI among mothers was 20.63±2.53 kg/m2, while those among boys and girls were 15.19±1.62 kg/m2 and 14.86±1.37 kg/m2 (p<0.001), respectively. The BMI of mothers were significantly and highly correlated with HAZ (0.709) and BMIZ (0.748) (p<0.001) of children. These are indicative of a strong genetic component between maternal and child anthropometry. Conclusion. The results indicate significant associations between mothers’ and children’s nutritional status. Assessments of body composition and nutritional status using BMI, especially among mothers and their children, are recommended.

scholarly journals Cryptic intermediate snail host of the liver fluke Fasciola hepatica in Africa

2019 ◽  
Vol 12 (1) ◽  
Author(s):  
Anna Mahulu ◽  
Catharina Clewing ◽  
Björn Stelbrink ◽  
Fred D. Chibwana ◽  
Immaculate Tumwebaze ◽  
...  
Keyword(s):  
Cryptic Species ◽  
Fasciola Hepatica ◽  
Phylogenetic Analyses ◽  
Public Health Problem ◽  
Distinct Species ◽  
Sub Saharan Africa ◽  
Major Public Health Problem ◽  
Galba Truncatula ◽  
Divergence Time Estimates ◽  
Sub Saharan

Abstract Background Snails such as Galba truncatula are hosts for trematode flukes causing fascioliasis, a zoonosis that is a major public health problem. Galba truncatula has recently been shown to be a cryptic species complex. African populations of Galba spp. are not yet studied using molecular assessments and is imperative to do so and reconstruct the centre of origin of Galba and to understand when and by what means it may have colonized the highlands of Africa and to what extent humans might have been involved in that process. Methods Samples from all known sub-ranges throughout Africa and new samples from Europe and Asia were obtained. We used a combination of two mitochondrial (cox1 and 16S) and one nuclear (ITS2) markers and phylogenetic, divergence time estimates and phylogeographical methods to determine the identity and biogeographical affinities. We also reconstructed the colonization history including the likely mode of dispersal and tested for the presence of cryptic Galba species in Africa. Results Galba truncatula is restricted to the Palaearctic region of the continent, namely Morocco. All sub-Saharan populations proved to be a distinct species according to the phylogenetic analyses and genetic distance. We propose to use the existing name Galba mweruensis (Connolly, 1929) for this species which is morphologically indistinguishable from the other two species hitherto known to occur in northern Africa, i.e. G. truncatula and G. schirazensis. Sub-tropical Africa has been colonized only once in either the Pliocene and possibly Miocene. Diversification within G. mweruensis is dated to the Plio-Pleistocene and thus human-mediated dispersal can be ruled out for the initial colonization of the isolated mountain ranges. There are potentially even more cryptic species in high altitude areas of Africa as outlined by the distinctness of the population found at the top of Mt. Elgon, Uganda. Conclusions From a novel genetic inspection of available African material, a hitherto neglected distinct species, G. mweruensis, now appears a major host of F. hepatica throughout sub-Saharan Africa. A closer examination of trematode parasites hosted by this species is needed in order to understand transmission patterns in highlands throughout eastern and southern Africa. We encourage future studies to inspect other high altitudes areas in Africa in light of parasites of either veterinary or medical importance.

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