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Ogola, J. G.

Publications and source records attributed to Ogola, J. G..

3 recordsLinked to original sources

Bartonella and hemotropic Mycoplasma species in synanthropic bats in Kenya

Identifying and characterizing zoonotic pathogens in wildlife is essential for understanding disease risk to humans. In Sub-Saharan Africa, many people live with bats in their houses and are exposed to their pathogens, yet little is known about the bacterial pathogens in Afrotropical bat species. Globally, Bartonella spp. (bartonellae) and hemotropic Mycoplasma spp. (hemoplasmas) are common bacterial pathogens in bats, and some lineages are known to spill over and cause infections in humans. To evaluate this disease risk, we screened three common synanthropic bat species in Kenya, and their ectoparasites, for hemoplasmas and bartonellae and assessed their relatedness to known human pathogens. Of 767 bats across 21 sites, 17.9% of bats were Bartonella spp. positive and 19.3% were hemoplasma positive. Bat ectoparasites had similar Bartonella prevalence (13.5-25.0%) and, for most bat species, ectoparasite loads were not associated with increased likelihood of Bartonella infection. We found that Bartonella lineages displayed phylogenetic overlap between different bat species and ectoparasites, suggesting pathogen sharing between species, while hemoplasma lineages corresponded strictly to host taxonomy. Finally, we found that 16S rRNA sequences from one heart-nosed bat (Cardioderma cor) were 97.85% similar to a human-associated hemoplasma found previously in Schreibers bats (Miniopterus schreibersii) in Spain. We show that synanthropic bats host bacteria of potential public health concern, highlighting the need to investigate the emerging impacts of these pathogens on human health in Kenya and elsewhere in Sub-Saharan Africa.

ecology↗

Rat hepatitis E virus and novel paramyxoviruses in synanthropic rodents and shrews in Kenya

The majority of emerging infectious diseases are zoonotic, having their origin in wildlife before spilling over into the human population. While small mammals are recognized as critical reservoirs for these viruses, their viral diversity remains largely uncharacterized across many African countries. We conducted molecular surveillance of synanthropic rodents and shrews in the Kibera informal settlement in Nairobi and the rural Taita Hills region of Kenya to detect and characterize potential zoonotic viruses. Tissue samples from 228 rodents and shrews were screened for six viral families using PCR assays. Rat hepatitis E virus (HEV) (Rocahepevirus ratti), a rodent-associated virus with potential for human spillover, was identified in Mus musculus and Rattus norvegicus from Kibera. NGS was conducted for the HEV positive samples, and we obtained two near-complete HEV genomes from Rattus norvegicus, which clustered within rodent-associated HEV genotypes in the phylogenetic analysis. The two sequences from the Rattus norvegicus cluster together, indicating a close genetic relationship. Paramyxoviruses belonging to the genera Jeilongvirus and Parahenipavirus were detected both from Taita and Kibera in nine different samples from Rattus norvegicus, Mus minutoides, Crocidura sp and Acomys ignitus. One paramyxovirus positive sample (Acomys ignitus) from Taita was selected for further sequencing with NGS, and a complete genome of a new jeilongvirus was assembled. Phylogenetic analysis of the detected viruses confirmed the close relation to previously known rodent-borne jeilongviruses but also revealed potentially novel jeilong- and parahenipavirus species. Our findings highlight the circulation of potentially zoonotic viruses in both urban and rural small mammals in Kenya. It emphasizes the necessity of continued genomic surveillance of zoonotic viruses to mitigate risks of their spillover into human populations. HighlightsO_LISurveillance reveals diverse rodent-borne viruses circulating in Kenya. C_LIO_LIRat-HEV was detected in Rattus norvegicus and Mus musculus from an urban low-income area. C_LIO_LIParamyxoviruses were detected across multiple rodent and shrew species, including novel Acomys ignitus jeilongvirus. C_LI Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=139 SRC="FIGDIR/small/719784v1_ufig1.gif" ALT="Figure 1"> View larger version (66K): org.highwire.dtl.DTLVardef@86c94aorg.highwire.dtl.DTLVardef@10946adorg.highwire.dtl.DTLVardef@1ff45eforg.highwire.dtl.DTLVardef@4876f1_HPS_FORMAT_FIGEXP M_FIG C_FIG

microbiology↗

Role of livestock parameters on cattle vulnerability to drought in the coastal semi-arid areas, Kenya

Livestock keeping forms main occupation in arid and semi-arid lands. Increase in drought frequency and intensity globally negatively affect livestock production and livelihood. Cattle are the most drought sensitive livestock due to size, grazing behavior and nutritional requirements. Factors for vulnerability of cattle to droughts are individual cattle parameters, health and husbandry practices. This cross sectional study aimed to those factors in semi-arid Kaloleni sub-county. Data on household (HH) head demographics, cattle and production collected from 194 enrolled HH using structured questionnaires. Cattle ages were grouped into young (<1 year old), growers (1-2 years old) and adults (>2years old). Data was analyzed using STATA 12 software. Univariate, bivariate and multivariate logistic regression analysis conducted and reported in Crude Odds Ratio (cOR), Adjusted Odds Ratio (aOR) and Confidence Interval (CI). We used Pearson product-moment correlation to determine relationship between HH head, cattle herd, individual cattle characteristics and drought characteristics, p = <0.05 being significant. Mean age HH heads was 40.7 {+/-} 12.6 years, 44.3% (86) had basic education, males were 65.3% (n=126). Mixed livestock production was practiced by 69.1% (134), while 86.1% (167) practiced free range communal grazing. Adult cattle were 54.1% (1295). Female cattle were 72.7% (1741). Average body condition score was 3.0 {+/-} 0.6, and calves had 2.6 {+/-} 1.3. About 20.6% had various forms of illness, calves mostly affected at 29.1%. Up to 63.4% HH, spray cattle at home, 93.3% HH reported no vaccination history. Home straying was protective (cOR 0.3, 95% CI 0.14 - 0.53). Herd size (aOR 2.9, 95% CI 1.5 - 5.5) and having no disease control method (aOR 2.8, 95% CI 1.85 - 9.19) were contributing to reporting disease. We report positive correlation between drought outcomes and HH head (r=0.076, p>0.01), cattle herd (r=0.216, p=0.003 and individual cattle characteristics(r=0.139, p>0.01). The findings on cattle conditions exacerbate their vulnerability in presence of stressful conditions like droughts especially in calves and cows. This study demonstrates weak disease control efforts and unorganized husbandry practices. We propose strategic and focused disease control plans to improve cattle resilience and further research on livestock based factors as drought response metrics for the livestock livelihood.

ecology↗