Codetection of Respiratory Syncytial Virus in Habituated Wild Western Lowland Gorillas and Humans During a Respiratory Disease Outbreak

Abstract

Pneumoviruses have been identified as causative agents in several respiratory disease outbreaks in habituated wild great apes. Based on phylogenetic evidence, transmission from humans is likely. However, the pathogens have never been detected in the local human population prior to or at the same time as an outbreak. Here, we report the first simultaneous detection of a human respiratory syncytial virus (HRSV) infection in western lowland gorillas (Gorilla gorilla gorilla) and in the local human population at a field program in the Central African Republic. A total of 15 gorilla and 15 human fecal samples and 80 human throat swabs were tested for HRSV, human metapneumovirus, and other respiratory viruses. We were able to obtain identical sequences for HRSV A from four gorillas and four humans. In contrast, we did not detect HRSV or any other classic human respiratory virus in gorilla fecal samples in two other outbreaks in the same field program. Enterovirus sequences were detected but the implication of these viruses in the etiology of these outbreaks remains speculative. Our findings of HRSV in wild but human-habituated gorillas underline, once again, the risk of interspecies transmission from humans to endangered great apes.

Keywords: enterovirus; great apes; noninvasive detection; respiratory disease; respiratory syncytial virus; western lowland gorillas.

Figure 1

Map of field site.

Figure 2

Phylogenetic positions of enteroviruses found in a human and a gorilla and two years later in another gorilla group during respiratory disease outbreaks. EVs were named as follows: ‘Gor_EV_ob_1’ Gorilla Enterovirus outbreak 1, ‘Hum_EV_ob_1’ human enterovirus outbreak 1, ‘Gor_EV_ob_3’ Gorilla Enterovirus outbreak 3. This tree is a maximum clade credibility tree generated from the output of Bayesian Markov chain Monte Carlo (BMCMC) analyses. We also ran maximum likelihood (ML) analyses; the ML tree was topologically very similar. Branch robustness was assessed through posterior probabilities (BMCMC) and nonparametric bootstrapping (ML); posterior probabilities/bootstrap values are plotted above branches.