New case definition raises number of pregnant women infected with Zika

NEW YORK — The number of pregnant women in the United States infected with Zika virus is suddenly tripling, due to a change in how the government is reporting cases.

[...] in the last year, infections in pregnant women have been strongly linked to fetal deaths and to potentially devastating birth defects, mostly in Brazil.

Experts think mosquitoes on the U.S. mainland will probably start spreading the virus in the months ahead, when hot weather hits and mosquito populations boom.

[...] Dr. Neil Silverman, a UCLA professor of obstetrics who has been advising the California Department of Public Health on Zika issues, explained the change in method does not indicate a greater risk of infection.

Only an estimated 1 in 5 people infected with Zika develop symptoms — fever, rash, joint pain, and red eyes — which usually last no more than a week.