A study to determine whether the Zika virus is causing babies to be born with the birth defect microephaly began in Brazil Monday.
A 16-member team of the U.S. Centers for Disease Control and Prevention started work in Joao Pessoa, in northeastern Brazil, that is the epicenter of the country's Zika outbreak.
Team members, working with members of Brazil's Health Ministry and officials from Paraiba state, will fan out though Paraiba on Tuesday to track down babies with microcephaly – a condition marked by an abnormally small head size -- and their mothers.
The team will use blood samples to help determine whether the mothers are infected with Zika.
The World Health Organization declared the Zika outbreak an international health emergency February 1.
The WHO cited a "strongly suspected" relationship between Zika infection in pregnancy and microcephaly, although much remains unknown about Zika.
Also Monday, Cuba plans to deploy more than 9,000 army troops and police officials in an effort to keep the Zika virus out of the island nation, President Raul Castro said in Granma, the state-run newspaper.
"The Revolutionary Armed Forces will assign more than 9,000 troops, among them active duty officers and reserve officers ... to the anti-vector and cleanup efforts, with the additional support of 200 officers of the National Revolutionary Police," Castro said.
He called upon all Cuban residents to assist troops and police in their efforts to spray neighborhoods and eliminate breeding spots for the Aedes genus of mosquitoes, which spreads the Zika virus.
'Take up this battle'
"It's necessary for every single Cuban to take up this battle as a personal matter," Castro told Granma.
One Health Ministry employee, who asked not to be identified as she was not authorized to talk with journalists, told Reuters the country's vast network of neighborhood doctors and clinics were put on alert for the virus weeks ago.
"There are no confirmed cases yet, but there will be. To date there have been two suspected cases that turned out negative," said the employee, who has real-time access to epidemiological data.
The Health Ministry plan to deal with the Zika virus will also help combat other mosquito-borne diseases, such as dengue and chikungunya, Castro said.
Some material for this report came from AP and Reuters.
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