There are now 433 pregnant women in the U.S. who have displayed laboratory evidence of Zika virus infection, according to the CDC's Thursday update. This marks an upswing of 33 cases since the last CDC update on July 21. Additionally, 13 infants in the U.S. have been born with Zika-related birth defects like microcephaly.
The total number of Zika cases in the U.S. reached 1,658 as of July 28, according to the CDC. All of these cases have been associated with travel to countries with active local transmission, except one which was accidentally acquired in a laboratory setting. Fifteen of the travel-associated cases were transmitted sexually. The first ever female-to-male sexual Zika transmission was recently reported in New York.
However, four cases under investigation in the state of Florida have displayed strong evidence for local, mosquito-borne Zika transmission. If these cases are confirmed, it will indicate that Zika has infiltrated the U.S. mosquito population.
Alaska, Idaho, Wyoming and South Dakota are the only states that remain Zika-free.
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