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In the last 300 thousand years, the genus Chlorocebus expanded from equatorial Africa into the southernmost latitudes of the continent, where colder climate was a probable driver of natural selection. We investigated population-level genetic variation in the mitochondrial uncoupling protein 1 (UCP1) gene region—implicated in non-shivering thermogenesis (NST)—in 73 wild savannah monkeys from three taxa representing this southern expansion (Chlorocebus pygerythrus hilgerti, Chlorocebus cynosuros and Chlorocebus pygerythrus pygerythrus) ranging from Kenya to South Africa. We found 17 single nucleotide polymorphisms with extended haplotype homozygosity consistent with positive selective sweeps, 10 of which show no significant linkage disequilibrium with each other. Phylogenetic generalized least-squares modelling with ecological covariates suggest that most derived allele frequencies are significantly associated with solar irradiance and winter precipitation, rather than overall low temperatures. This selection and association with irradiance is demonstrated by a relatively isolated population in the southern coastal belt of South Africa. We suggest that sunbathing behaviours common to savannah monkeys, in combination with the strength of solar irradiance, may mediate adaptations to thermal stress via NST among savannah monkeys. The variants we discovered all lie in non-coding regions, some with previously documented regulatory functions, calling for further validation and research. [ABSTRACT FROM AUTHOR]

Quantitative knowledge on the contribution of African buffalo to the epidemiology of foot‐and‐mouth disease virus (FMDV) in East Africa is lacking, and this information is essential for the design of control programs in the region. The objective of this study was to investigate the epidemiology of FMDV in buffalo, including the role of buffalo in the circulation of FMDV in livestock populations. We collected blood and oropharyngeal fluids from 92 wild buffalo and 98 sympatric cattle in central Kenya and sequenced the virus' VP1 coding region. We show that FMDV has a high seroprevalence in buffalo (~77%) and targeted cattle (~93%). In addition, we recovered 80 FMDV sequences from buffalo, all of which were serotype SAT1 and SAT2, and four serotype O and A sequences from sympatric cattle. Notably, six individual buffalo were co‐infected with both SAT1 and SAT2. Amongst sympatric buffalo and cattle, the fact that no SAT1 or 2 sequences were found in cattle suggests that transmission of FMDV from buffalo to sympatric cattle is rare. Similarly, there was no evidence that serotype O and A sequences found in cattle were transmitted to buffalo. However, viruses from FMDV outbreaks in cattle elsewhere in Kenya were closely related to SAT1 and SAT2 viruses found in buffalo in this study, suggesting that FMDV in cattle and buffalo do not constitute independently evolving populations. We also show that fine‐scale geographic features, such as rivers, influence the circulation of FMDV in buffalo and that social segregation amongst sympatric herds may limit between‐herd transmission. These results significantly advance our understanding of the ecology and molecular epidemiology of FMDV at wildlife–livestock interfaces in East Africa and will help to inform the design of control and surveillance strategies for this disease in the region. [ABSTRACT FROM AUTHOR]

Background: Simian immunodeficiency virus (SIV) naturally infects African non‐human primates (NHPs) and poses a threat of transmission to humans through hunting and consumption of monkeys as bushmeat. This study investigated the as of yet unknown molecular diversity of SIV in free‐ranging Chlorocebus species (African green monkeys—AGMs) and Papio anubis (olive baboons) within Mombasa, Kisumu and Naivasha urban centres in Kenya. Methods: We collected blood samples from 124 AGMs and 65 olive baboons in situ, and detected SIV by high‐resolution melting analysis and sequencing of PCR products. Results: Simian immunodeficiency virus prevalence was 32% in AGMs and 3% in baboons. High‐resolution melting (HRM) analysis demonstrated distinct melt profiles illustrating virus diversity confirmed by phylogenetic analysis. Conclusions: There is persistent evolutionary diversification of SIVagm strains in its natural host, AGMs and cross‐species infection to olive baboons is occurring. Further study is required to establish pathogenesis of the diverse SIVagm variants and baboon immunological responses. [ABSTRACT FROM AUTHOR]

Understanding the dynamics of foot‐and‐mouth disease virus (FMDV), an endemic and economically constraining disease, is critical in designing control programmes in Africa. This study investigates the evolutionary epidemiology of SAT1 and SAT2 FMDV in Eastern Africa, as well as between cattle and wild African buffalo. Bayesian phylodynamic models were used to analyse SAT1 and SAT2 VP1 gene segments collected between 1975 and 2016, focusing on the SAT1 and SAT2 viruses currently circulating in Eastern Africa. The root state posterior probabilities inferred from our analyses suggest Zimbabwe as the ancestral location for SAT1 currently circulating in Eastern Africa (p = 0.67). For the SAT2 clade, Kenya is inferred to be the ancestral location for introduction of the virus into other countries in Eastern Africa (p = 0.72). Salient (Bayes factor >10) viral dispersal routes were inferred from Tanzania to Kenya, and from Kenya to Uganda for SAT1 and SAT2, respectively. Results suggest that cattle are the source of the SAT1 and SAT2 clades currently circulating in Eastern Africa. In addition, our results suggest that the majority of SAT1 and SAT2 in livestock come from other livestock rather than wildlife, with limited evidence that buffalo serve as reservoirs for cattle. Insights from the present study highlight the role of cattle movements and anthropogenic activities in shaping the evolutionary history of SAT1 and SAT2 in Eastern Africa. While the results may be affected by inherent limitations of imperfect surveillance, our analysis elucidates the dynamics between host species in this region, which is key to guiding disease intervention activities. [ABSTRACT FROM AUTHOR]

Disease spreads as a result of people moving and coming in contact with each other. Thus the mobility patterns of individuals are crucial in understanding disease dynamics. Here we study the impact of human mobility on HIV transmission in different parts of Kenya. We build an SIR metapopulation model that incorporates the different regions within the country. We parameterise the model using census data, HIV data and mobile phone data adopted to track human mobility. We found that movement between different regions appears to have a relatively small overall effect on the total increase in HIV cases in Kenya. However, the most important consequence of movement patterns was transmission of the disease from high infection to low prevalence areas. Mobility slightly increases HIV incidence rates in regions with initially low HIV prevalences and slightly decreases incidences in regions with initially high HIV prevalence. We discuss how regional HIV models could be used in public-health planning. This paper is a first attempt to model spread of HIV using mobile phone data, and we also discuss limitations to the approach. [ABSTRACT FROM AUTHOR]

Africa is faced with a myriad of challenges, such as HIV/ AIDS, malaria, tuberculosis, and a variety of political and historical complications that have affected the educational system for advanced nursing practice. In Kenya, the current situation in the higher education sector does not give nurses an opportunity to pursue graduate education after they have acquired the basic diploma in nursing due to limited government support and the type of education system existing in the country today. Although distance education has been available in Kenya for professionals such as teachers, in public universities, this kind of opportunity is unreachable for nurses who are working and need to further their education. Nurses desire to have access to advanced practice education to equip them with the relevant knowledge to cope and address the complex health issues arising in the management and care of patients. A collaborative model is presented as a potential solution for this need. Four major constituents are identified including hospitals and agencies, communities of interest, Kenyan universities and international education partners. Each has a part to play including contributions to information, communication of opinion and expertise, money and support, infrastructure and in-kind resources. Distance education is cost-effective and will help in building capacity at various levels of nursing including leadership in clinical practice, teaching, administration and research. [ABSTRACT FROM AUTHOR]

Attitudes and beliefs about antiretroviral therapy (ART) may affect sexual risk behaviors among the general population in sub-Saharan Africa. We performed a cross-sectional population-based study in Kisumu, Kenya to test this hypothesis in October 2006. A total of 1655 participants were interviewed regarding attitudes and beliefs about ART and their sexual risk behaviors. The majority of participants, (71%) men and (70%) women, had heard of ART. Of these, 20% of men and 29% of women believed ART cures HIV. Among women, an attitude that “HIV is more controllable now that ART is available” was associated with sex with a non-spousal partner, increased lifetime number of sexual partners as well as a younger age at sexual debut. No significant associations with this factor were found among men. The belief that “ART cures HIV” was associated with younger age of sexual debut among women. The same belief was associated with an increased likelihood of exchanging sex for money/gifts and decreased likelihood of condom use at last sex among men. These findings were most significant for people aged 15–29 years. In high HIV seroprevalence populations with expanding access to ART, prevention programs must ensure their content counteracts misconceptions of ART in order to reduce high risk sexual behaviors, especially among youth. [ABSTRACT FROM PUBLISHER]

Objective: We conducted a community survey to estimate the prevalence and describe the features, risk factors, and consequences of convulsive status epilepticus (CSE) among people with active convulsive epilepsy (ACE) identified in a multisite survey in Africa., Methods: We obtained clinical histories of CSE and neurologic examination data among 1,196 people with ACE identified from a population of 379,166 people in 3 sites: Agincourt, South Africa; Iganga-Mayuge, Uganda; and Kilifi, Kenya. We performed serologic assessment for the presence of antibodies to parasitic infections and HIV and determined adherence to antiepileptic drugs. Consequences of CSE were assessed using a questionnaire. Logistic regression was used to identify risk factors., Results: The adjusted prevalence of CSE in ACE among the general population across the 3 sites was 2.3 per 1,000, and differed with site (p < 0.0001). Over half (55%) of CSE occurred in febrile illnesses and focal seizures were present in 61%. Risk factors for CSE in ACE were neurologic impairments, acute encephalopathy, previous hospitalization, and presence of antibody titers to falciparum malaria and HIV; these differed across sites. Burns (15%), lack of education (49%), being single (77%), and unemployment (78%) were common in CSE; these differed across the 3 sites. Nine percent with and 10% without CSE died., Conclusions: CSE is common in people with ACE in Africa; most occurs with febrile illnesses, is untreated, and has focal features suggesting preventable risk factors. Effective prevention and the management of infections and neurologic impairments may reduce the burden of CSE in ACE., (© 2015 American Academy of Neurology.)