No. Even in areas where the virus is circulating, very few mosquitoes are infected with the virus. Even if the mosquito is infected, less than 1 percent of people who get bitten and become infected will get severely ill. The chances you will become severely ill from any one mosquito bite are extremely small.
No. WNV is not transmitted person-to-person or from infected animals to people.
There is one documented case of transplacental (mother-to-child) transmission of WNV in humans. Although the newborn in this case was infected with WNV at birth and had severe medical problems, it is unknown whether the WNV infection itself caused these problems or whether they were coincidental. Nevertheless, pregnant women should take precautions to reduce their risk for WNV and other arboviral infections by using protective clothing and insect repellents containing DEET to avoid mosquitoes.
Infected mosquitoes are the primary source for WNV. Although ticks infected with WNV have been found in Asia and Africa, their role in the transmission and maintenance of the virus is uncertain. In addition, there is no information to suggest that ticks have played any role in the cases identified in the United States.
Following transmission by an infected mosquito, WNV multiplies in the person's blood system and crosses the blood-brain barrier to reach the brain. The virus interferes with normal central nervous system functioning and causes inflammation of brain tissue. Recommended Web sites: