Non-Invasive Body Temperature Measurement of Wild Chimpanzees Using Fecal Temperature Decline

New methods are required to increase our understanding of pathologic processes in wild mammals. We developed a noninvasive field method to estimate the body temperature of wild living chimpanzees habituated to humans, based on statistically fitting temperature decline of feces after defecation. The method was established with the use of control measures of human rectal temperature and subsequent changes in fecal temperature over time. The method was then applied to temperature data collected from wild chimpanzee feces. In humans, we found good correspondence between the temperature estimated by the method and the actual rectal temperature that was measured (maximum deviation 0.22 C). The method was successfully applied and the average estimated temperature of the chimpanzees was 37.2 C. This simple-to-use field method reliably estimates the body temperature of wild chimpanzees and probably also other large mammals.Human Evolutionary Biolog

Immunisation with a Multivalent, Subunit Vaccine Reduces Patent Infection in a Natural Bovine Model of Onchocerciasis during Intense Field Exposure

Human onchocerciasis, caused by the filarial nematode Onchocerca volvulus, is controlled almost exclusively by the drug ivermectin, which prevents pathology by targeting the microfilariae. However, this reliance on a single control tool has led to interest in vaccination as a potentially complementary strategy. Here, we describe the results of a trial in West Africa to evaluate a multivalent, subunit vaccine for onchocerciasis in the naturally evolved host-parasite relationship of Onchocerca ochengi in cattle. Naïve calves, reared in fly-proof accommodation, were immunised with eight recombinant antigens of O. ochengi, administered separately with either Freund's adjuvant or alum. The selected antigens were orthologues of O. volvulus recombinant proteins that had previously been shown to confer protection against filarial larvae in rodent models and, in some cases, were recognised by serum antibodies from putatively immune humans. The vaccine was highly immunogenic, eliciting a mixed IgG isotype response. Four weeks after the final immunisation, vaccinated and adjuvant-treated control calves were exposed to natural parasite transmission by the blackfly vectors in an area of Cameroon hyperendemic for O. ochengi. After 22 months, all the control animals had patent infections (i.e., microfilaridermia), compared with only 58% of vaccinated cattle (P = 0.015). This study indicates that vaccination to prevent patent infection may be an achievable goal in onchocerciasis, reducing both the pathology and transmissibility of the infection. The cattle model has also demonstrated its utility for preclinical vaccine discovery, although much research will be required to achieve the requisite target product profile of a clinical candidate

Fatal ulcerative colitis in a western lowland gorilla (Gorilla gorilla gorilla).

A captive western lowland gorilla (Gorilla gorilla gorilla) presented with watery diarrhoea that progressed to become profuse and haemorrhagic. Faecal analyses revealed Balantidium (B.) coli trophozoites and salmonella-like bacteria. Despite treatment the gorilla died on the 5th day after onset of symptoms. Post-mortem examination revealed a severe erosive-ulcerative superficial and deep colitis. Histological examination of post-mortem samples of the colon showed plentiful B. coli invading into the mucosa and submucosa, whilst PCR screening of bacterial DNA could not confirm any bacteria species which could be connected to the clinical picture. As B. coli is usually a non-pathogenic gut commensal, and as this animal previously showed evidence of non-symptomatic infection of B. coli, it is possible that the switch in pathogenicity was triggered by an acute bacterial infection. Despite successful treatment of the bacterial infection the secondary deep invasion of B. coli was not reversed, possibly because of the failure of the treatment regimen, and led to the death of the gorilla

Origin of Human T-Lymphotropic Virus Type 1 in Rural Côte d’Ivoire

Simian T-lymphotropic virus type 1 (STLV-1) strains occasionally infect humans. However, the frequency of such infections is unknown. We show that direct transmission of STLV-1 from nonhuman primates to humans may be responsible for a substantial proportion of human T-lymphotropic virus type 1 infections in rural Côte d’Ivoire, where primate hunting is common

Interspecies Transmission of Simian Foamy Virus in a Natural Predator-Prey System ▿

Simian foamy viruses (SFV) are ancient retroviruses of primates and have coevolved with their host species for as many as 30 million years. Although humans are not naturally infected with foamy virus, infection is occasionally acquired through interspecies transmission from nonhuman primates. We show that interspecies transmissions occur in a natural hunter-prey system, i.e., between wild chimpanzees and colobus monkeys, both of which harbor their own species-specific strains of SFV. Chimpanzees infected with chimpanzee SFV strains were shown to be coinfected with SFV from colobus monkeys, indicating that apes are susceptible to SFV superinfection, including highly divergent strains from other primate species

Prevalence and burden of <i>O. ochengi</i> in vaccinated and control animals at 22 months post-exposure.

a<p>Bold type indicates statistical significance at the <i>P</i><.05 level.</p>b<p>Fisher's exact test.</p>c<p>Mann-Whitney <i>U</i> test.</p>d<p>One animal was negative at this time-point but had been positive on prior occasions.</p

Total area-under-curve (OD_{405 nm}) for IgG1 and IgG2 responses to eight <i>Onchocerca ochengi</i> recombinant antigens.

<p>‘Vaccinated, patent’ (<i>n</i> = 7) or ‘vaccinated, non-patent’ (<i>n</i> = 5) refers to presence or absence of dermal microfilariae at 22 months post-exposure, respectively; all adjuvant-control animals had patent infections (<i>n</i> = 13). Area-under-curve was calculated from data obtained at 0, 4 and 21 months post-exposure. Box-and-whisker plots display the median line, 25^th–75^th IQR (box), highest and lowest values within 1.5× IQR (whiskers), outliers (○; >1.5–3.0×IQR) and extreme values (▹; >3.0×IQR).</p

Schedule of injections.

<p>Notes FCA, Freund's complete adjuvant; FIA, Freund's incomplete adjuvant; PBS, phosphate-buffered saline.</p>a<p>Preceding natural exposure to infection.</p>b<p>Adjuvant controls received an equivalent volume of PBS instead of antigen, in combination with vehicle, following an identical schedule to vaccinated animals.</p>c<p>Final injection in the Freund's series.</p