Diversity, prevalence, and intensity of gastrointestinal helminth infections in migratory, resident, and sedentary plains zebras (Equus quagga) in Masai Mara National Reserve and Lake Nakuru National Park, Kenya.

The diversity, prevalence and intensity of parasitic infections are influenced by factors such as movement patterns and land area available to the host. Zebras are known to harbour various genera of gastrointestinal helminths and facilitate parasite movement across large geographic areas through migration. Despite the harmful effects of helminths and their consequences on host population dynamics, little is known regarding helminth infection patterns in migratory, resident, and sedentary zebras. This study compared the diversity, prevalence, and intensity of helminth infections in zebras with different host movement patterns and space availability. Faecal samples were collected from migratory, resident, and sedentary groups of zebras between 2014 and 2015 and screened for helminth infection. They were infected by diverse groups of helminths including nematodes, trematodes and cestodes with the most prevalent being strongyle type nematodes. No significant difference in the diversity and prevalence was observed between the "three groups". Larvae were also recovered and identified species, cyathostomes, Strongylus edentatus, S.vulgaris, S. equinus, and Trichostronglus in order of abundance. The intensity of infection with the strongyle type nematodes, was highest in the migratory, then sedentary and lowest in resident zebras. It is plausible that the migratory zebras have higher energy demands and poor nutrition, resulting in reduced immune function hence high nematode burdens. Similarly, the sedentary population had high nematode burdens possibly due to high pasture contamination and depressed immunity due to the artificially restricted movement. The latter observation is particularly important in the design and size of sanctuaries in relation to parasitism.

Three Novel Haplotypes of Theileria bicornis in Black and White Rhinoceros in Kenya.

Piroplasms, especially those in the genera Babesia and Theileria, have been found to naturally infect rhinoceros. Due to natural or human-induced stress factors such as capture and translocations, animals often develop fatal clinical piroplasmosis, which causes death if not treated. This study examines the genetic diversity and occurrence of novel Theileria species infecting both black and white rhinoceros in Kenya. Samples collected opportunistically during routine translocations and clinical interventions from 15 rhinoceros were analysed by polymerase chain reaction (PCR) using a nested amplification of the small subunit ribosomal RNA (18S rRNA) gene fragments of Babesia and Theileria. Our study revealed for the first time in Kenya the presence of Theileria bicornis in white (Ceratotherium simum simum) and black (Diceros bicornis michaeli) rhinoceros and the existence of three new haplotypes: haplotypes H1 and H3 were present in white rhinoceros, while H2 was present in black rhinoceros. No specific haplotype was correlated to any specific geographical location. The Bayesian inference 50% consensus phylogram recovered the three haplotypes monophyleticly, and Theileria bicornis had very high support (BPP: 0.98). Furthermore, the genetic p-uncorrected distances and substitutions between T. bicornis and the three haplotypes were the same in all three haplotypes, indicating a very close genetic affinity. This is the first report of the occurrence of Theileria species in white and black rhinoceros from Kenya. The three new haplotypes reported here for the first time have important ecological and conservational implications, especially for population management and translocation programs and as a means of avoiding the transport of infected animals into non-affected areas.

First reported case of fatal tuberculosis in a wild African elephant with past human-wildlife contact.

Tuberculosis is emerging/re-emerging in captive elephant populations, where it causes morbidity and deaths, although no case of TB in wild African elephants has been reported. In this paper we report the first case of fatal TB in an African elephant in the wild. The infection with Mycobacterium tuberculosis was confirmed by post-mortem and histological examinations of a female sub-adult elephant aged >12 years that died in Tsavo East National Park, Kenya, while under treatment. This case is unique in that during its lifetime the elephant had contact with both humans and wild elephants. The source of the infection was unclear because the elephant could have acquired the infection in the orphanage or in the wild. However, our results show that wild elephants can maintain human TB in the wild and that the infection can be fatal.

Molecular cloning and characterization of Th1 and Th2 cytokines of African buffalo (Syncerus caffer).

The African buffalo (Syncerus caffer) has been implicated as the reservoir of several bovine infectious agents. However, there is insufficient information on the protective immune responses in the African buffalo, particularly in infected animals. In this study, we analysed Th1 cytokines IL-2 and IFN-γ, and Th2 cytokines IL-4 and IL-10. The cloned cDNA of IL-2, IL-4, IL-10 and IFN-γ contained an open reading frame of 468, 501, 408 and 540 nucleotides, encoding polypeptides of 155, 166, 135 and 179 amino acids, respectively. Nucleotide sequence homology of IL-2, IFN-γ and IL-4 was more than 98% between the African buffalo and cattle, which resulted in identical polypeptides. Meanwhile, IL-10 gene of African buffalo and cattle had 95% homology in nucleotide sequence, corresponding to thirteen amino acid residues substitution. Cysteine residues and potential glycosylation sites were conserved within the family Bovinae. Phylogenetic analyses including cytokines of the African buffalo placed them within a cluster comprised mainly of species belonging to the order Artiodactyla, including cattle, water buffalo, sheep, goat, pig and artiodactyl wildlife. A deeper understanding of the structure of these cytokines will shed light on their protective role in the disease-resistant African buffalo in comparison with other closely related species.

The opportunistic Sarcoptes scabiei: a new episode from giraffe in the drought-suffering Kenya.

The ubiquitous Sarcoptes mite is unexplainable emerging and re-emerging parasite, threatening biodiversity and human health. When a new outbreak occurs, it is not clear if it is a genuine emergence resulting from a new incidence or apparent emergence resulting from increased detection. In this paper we report, for the first time to our knowledge, an outbreak of sarcoptic mange in giraffes in the wild. Three decaying carcasses and five free-ranging subadult reticulated giraffes were observed to have mange-like lesions in the drought-suffering Wajir Region in North Eastern Kenya, while apparently all sympatric wild and domestic animals were mange-free. Affected giraffes were captured and successfully treated. The possible relations between this outbreak and annual seasons, animal age-classes and sex, and spatial distribution are discussed.

Prevalence of antibodies against Rift Valley fever virus in Kenyan wildlife.

Rift Valley fever virus (RVFV) is an arbovirus associated with periodic outbreaks, mostly on the African continent, of febrile disease accompanied by abortion in livestock, and a severe, fatal haemorrhagic syndrome in humans. However, the maintenance of the virus during the inter-epidemic period (IEP) when there is low or no disease activity detected in livestock or humans has not been determined. This study report prevalence of RVFV-neutralizing antibodies in sera (n=896) collected from 16 Kenyan wildlife species including at least 35% that were born during the 1999-2006 IEP. Specimens from seven species had detectable neutralizing antibodies against RVFV, including African buffalo, black rhino, lesser kudu, impala, African elephant, kongoni, and waterbuck. High RVFV antibody prevalence (>15%) was observed in black rhinos and ruminants (kudu, impala, buffalo, and waterbuck) with the highest titres (up to 1:1280) observed mostly in buffalo, including animals born during the IEP. All lions, giraffes, plains zebras, and warthogs tested were either negative or less than two animals in each species had low (or= 1:80. These data provide evidence that wild ruminants are infected by RVFV but further studies are required to determine whether these animals play a role in the virus maintenance between outbreaks and virus amplification prior to a noticeable outbreak.

Antimicrobial susceptibility and plasmids from Escherichia coli isolated from rats.

OBJECTIVES: To determine if antimicrobial resistance occurs in E. coli isolated from rats and if this resistance is transferable via plasmids. METHODS: Sixty Escherichia coli isolates obtained from 215 rats trapped in and around Nairobi, Kenya, were analysed for antimicrobial susceptibility to eleven commonly used antimicrobials. Plasmid DNA analysis and in-vitro conjugation tests were conducted on twenty two resistant isolates. RESULTS: A total of 12 (20%) E. coli were resistant to at least one of the commonly used drugs including ampicillin, sulphamethoxazole and streptomycin. Eight (13.3%) isolates were multidrug resistant. The drug resistant E. coli fell into five plasmid profile groups with plasmids ranging between two and 98 megadaltons (Mda). Resistance to ampicillin was transferable. CONCLUSION: The results of this study show that rats from the study area may form an important reservoir for drug-resistant E. coli that could pose a public health hazard.

Antimicrobial resistance of bacterial organisms isolated from rats.

OBJECTIVE: To determine if antimicrobial resistance occurs in various bacterial species isolated from rats. METHOD: Two hundred and fifteen rats were trapped from areas in and around Nairobi, Kenya. They were sacrificed and their intestinal, liver and spleen specimens obtained. Various bacterial species were isolated from these specimens. The species were analysed for antimicrobial susceptibility to 12 commonly used antimicrobials using the disc diffusion technique. RESULTS: The bacterial species isolated included pathogenic and potentially pathogenic ones such as Escherichia coli 137, Salmonella typhimurium 1, Klebsiella pneumoniae 2, Enterobacter cloacae 4, Enterobacter sakazakii 2, Citrobacter freundii 3, Morganella morganii (2), Pseudomonas aeruginosa 2 and Burkhoddria cepacia 6. Depending on the species, the resistance to the various antimicrobials were: 0-100% for cefotaxime, nalidixic acid, cefuroxime, tetracycline, chloramphenicol, co-amoxyclav, sulfamethoxazole, ampicillin, trimethoprim and cephradine, 0-66.6% for gentamicin and 0-25% for apramycin. CONCLUSION: The results showed that, rats from the study area harboured bacterial species with antimicrobial resistance. These micro-organisms may form an important reservoir for antibiotic resistance which could pose a public health hazard. Control of rat populations, better management of sewer systems and waste dumping sites are recommended in order to reduce occurrence of these drug resistance reservoirs.