President Barack Obama's administration declared a public health emergency in Puerto Rico on Friday in response to the growing number of Zika virus cases that pose a "significant threat to public health," especially to pregnant women and women of childbearing age.
The US Department of Health and Human Services (HHS) on Friday declared the emergency as Puerto Rico said that there were 10,690 laboratory confirmed Zika cases on the Caribbean island of 3.5 million, including 1,035 pregnant women.
In a statement, HHS said the actual number of people infected with Zika is likely higher because most people with Zika infections have no symptoms and might not seek testing. The agency said the number of infections is expected to continue to rise through October, and by year's end a quarter of the island's population could be exposed.
In the US, Zika has only been spread by mosquitos in Puerto Rico and in South Florida, due to those two locations tropical climates. Puerto Rico is expected to be hit hardest, because of a lack of mosquito control infrastructure.
Zika can cause a birth defect called microcephaly, which results in developmental problems in infants and an abnormally sized head. The virus is spread by mosquitoes and by infected people through sexual intercourse.
In order to prevent Zika, HHS recommended people wear condoms, and prevent mosquito bites by wearing mosquito repellent, long sleeved shirts and pants, and staying in air-conditioned or screened rooms.
The declaration of a health emergency will give Puerto Rico access to additional funds to fight the spread of the virus. The US territory can also apply for funding to hire and train workers to assist in control and outreach efforts, and request local public health departments or agency personnel to be temporarily reassigned to assist in the Zika response.
"This emergency declaration allows us to provide additional support to the Puerto Rican government and reminds us of the importance of pregnant women, women of childbearing age, and their partners taking additional steps to protect themselves and their families from Zika," said US Health and Human Services Secretary Sylvia M. Burwell in a statement.
Also on Friday, three more cases of people infected with Zika by local mosquitoes were reported in Florida, bringing the total to 28. One of the cases included a person who does not live in Miami's one-square-mile "transmission zone," in the Wynwood neighborhood of Miami, where the health department believes local transmission is taking place.
The US Centers for Disease Control and Prevention has warned pregnant women to avoid the transmission zone.
Zika first appeared in Brazil, where it spread to the Caribbean and Latin America.
In February the Obama administration requested $1.9 billion to fight Zika, but the Republican-led Congress has not approved the funding.
The last time the Obama administration declared a public health emergency was during Hurricane Sandy in 2012.
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