Humans normally do not acquire FMD, but the serotypes that have been isolated include O (most commonly), C and rarely A. Humans can act as a fomite and transmit FMD to other animal species. As mentioned previously, humans can harbor the FMD virus in their respiratory tract for 1-2 days. Also, if their boots, clothing or vehicles become contaminated they can spread the virus to susceptible animals. Also, if humans ingest unprocessed milk or dairy products from infected animals, they are at risk for contracting infection. This too has very low incidence.