A human pathogenic hantavirus circulates and is shed in taxonomically diverse rodent reservoirs

Abstract

Background Orthohantaviruses are negative-sense RNA viruses that can cause hantavirus cardiopulmonary syndrome (HCPS) in humans. In the United States, Sin Nombre orthohantavirus (SNV) is the primary cause of HCPS, with a fatality rate of 36% and most cases occuring in the southwestern states. The western deer mouse, Peromyscus sonoriensis, is the primary reservoir for SNV; however, it remains unclear if alternative reservoirs exist. Results We conducted an extensive survey of SNV genetic prevalence in wild-caught small mammal communities throughout New Mexico and observed that 27% of all animals were positive for SNV. Through longitudinal trapping at a site of patient exposure, we found that SNV circulates at a high rate in multiple species over time. Furthermore, we isolated live SNV from tissues and feces from multiple small mammal species, demonstrating infectious virus in alternative and novel reservoirs. Significance Altogether, this work shows that SNV is widely prevalent and persistent throughout New Mexico in multiple small mammal reservoirs that can harbor and shed infectious virus. This encourages future work for additional surviellance efforts and revaluates host-species dynamics for New World hantaviruses. Author summary The first reported hantavirus cases in the United States occurred in the Four Corners region (Arizona, New Mexico, Utah and Colorado) and was found to be transmitted by the droppings of western deer mice. This led to discovery of Sin Nombre virus (SNV). Unlike hantaviruses found through Europe and Asia, SNV causes hantavirus cardiopulmonary syndrome (HCPS), which has a high mortality rate. It is generally thought that only one small mammal host is capable of carrying and transmitting hantavirus to humans. However, our group and others have found hantavirus genetic material in multiple small mammal species, but these studies have been fairly limited and did not determine if the virus could replicate in these species and be transmitted through them. Here, we conducted a large study to look for SNV in wild-caught rodents throughout New Mexico in counties with and without reported human HCPS cases. We found that SNV is widespread in all areas of NM and stably circulates in rodents at a site of human infection. Importantly, we show that multiple small mammal species can carry and shed infectious SNV. Altogether, our study provides a novel shift in the understanding of host reservoir dynamics for SNV.