Vulnerabilities for exposure to emerging infectious diseases at urban settlements in Nepal
A PREDICT-funded analysis of animal-human contact in temporary urban and peri-urban settlements along rivers in Kathmandu, Nepal finds rodents and shrews should be considered a health threat, and targeted surveillance for emerging pathogens could improve disease control and health security for urban populations.
Key Findings
- Humans living in these informal urban settlements are routinely exposed (half of survey respondents) to animals that could act as reservoir hosts for potentially infectious zoonotic pathogens
- Identified a range of non-zoonotic and potentially zoonotic RNA viruses for the first time in urban small mammal populations in the Kathmandu Valley, including new viruses within Paramyxoviridae and Rhabdoviridae families
- The detection of murine coronaviruses (do not cause disease in humans), along with the other viruses detected could be indicators of viral risk, especially within the context of these vulnerable settlements where there is direct evidence of frequent rodent–human contact
- Five of six viruses were detected in the peri-urban sampling site, indicating that viral shedding and subsequent diversity in these small mammal populations might be linked to land use or degree of fragmentation of habitat or urbanization
Informing Action
To more comprehensively characterize zoonotic disease risks at this unique human–animal interface, we have initiated follow-up investigations that assess the presence of viruses in domestic animals, evaluate people for virus presence or exposure, and better determine whether any of the viruses detected in rodents or shrews have spilled over into domestic species or people. To understand the real potential for viral sharing and transmission at this interface, including the new viruses we detected, longitudinal and concurrent surveillance of people, wildlife, and domestic animals will be important.