Implications of Tourist-Macaque Interactions for Disease Transmission

Abstract

During wildlife tourism, proximity or actual contact between people and animals may lead to a significant risk of anthropozoonotic disease transmission. In this paper, we use social network analysis, disease simulation modelling and data on animal health and behaviour to investigate such risks at a site in Morocco, where tourists come to see wild Barbary macaques (Macaca sylvanus). Measures of individual macaques' network centrality-an index of the strength and distribution of their social relationships and thus potentially their ability to spread disease-did not show clear and consistent relationships with their time spent in close proximity to, or rate of interacting with, tourists. Disease simulation modelling indicated that while higher-ranked animals had a significantly greater ability to spread disease within the group, in absolute terms there was little difference in the size of outbreaks that different individuals were predicted to cause. We observed a high rate of physical contact and close proximity between humans and macaques, including during three periods when the macaques were coughing and sneezing heavily, highlighting the potential risk of disease transmission. We recommend that general disease prevention strategies, such as those aimed at reducing opportunities for contact between tourists and macaques, should be adopted.

Keywords: Disease transmission risks; Macaca sylvanus; Modelling; Primates; Tourist–wildlife interactions; Wildlife tourism.

Fig. 1

The association network based on nearest neighbours within 10 m. The size of the nodes reflects the interaction rate with tourists. Grey-filled nodes are males, and white are females.

Fig. 2

Mean size of the predicted outbreak with each individual (n = 17) as patient zero (over 10,000 simulations) at four different values of basic reproductive number, R0 (0.7, 1.5, 3 and 10). Individuals are arranged in rank order (1–8 are males, and 9–17 are females), in order of descending rank.