Yellow fever, a mosquito-borne viral disease, is not normally found in the U.S. It typically appears in travelers to other countries where the disease is more prevalent, such as sub-Saharan Africa and tropical South America. It is maintained in nature as mosquitoes pass the disease among themselves, to monkeys, then back again. Humans may also serve as hosts for the disease.

Additional Resources

• Yellow fever vaccination clinics
• Centers for Disease Control and Prevention
• World Health Organization
• MEDLINEplus, a service of the U.S. National Library of Medicine and the National Institutes of Health