Specific similarities between the English sweating sickness and diseases caused by various species of hantavirus indicate that a hantavirus may have been the cause of the sweating sickness. Hantavirus species are zoonotic diseases which are carried by bats, rodents, and several insectivores. There are indications that the English sweating sickness may have been rodent borne. Evidence of this includes the seasonal occurrences, fluctuations multiple times a year, and the occasional cases which occurred between major outbreaks. Other diseases carried by rodents demonstrate similar trends.