Abstract
Transmission of human respiratory pathogens to wild, human-habituated great apes has been repeatedly documented within research and tourism projects. While the implementation of hygiene measures has significantly reduced the risk of pathogen introduction, vigilant surveillance remains essential to evaluate the effectiveness of the adopted measures and identify additional steps for risk reduction. Here, we combined behavioral observations and pathogen genomic surveillance in non-invasive samples to investigate three outbreaks of respiratory disease in human-habituated western lowland gorillas (Gorilla gorilla gorilla) across four sites within the Sangha Trinational Protected Area Network in the northwestern Congo Basin. Clinical signs of respiratory disease were recorded in three groups of monitored gorillas at two neighboring National Parks in the Central African Republic and Republic of Congo. Human respiratory syncytial viruses were identified as the causative agent for all three documented outbreaks. Genomic analyses revealed two distinct viral types suggesting independent introduction rather than intergroup transmission. All symptomatic individuals recovered. These findings highlight the importance of stringent prevention measures at great ape research sites and the need for addressing the burden of respiratory disease in neighboring human communities. The evolving integrated approach centered on the One Health concept in the Sangha Trinational Protected Area Network is proving beneficial to great ape conservation, the preservation of this high-biodiversity landscape and the public health of local communities.