Florida says first locally transmitted Zika cases ‘likely’

The governor of Florida said on Friday four people in the southern part of the state likely have contracted the Zika virus through local mosquito bites, in what would be the first such instances in the continental US.

The cases were not confirmed, as no insect trapped for testing has yet been proved to be carrying the disease. The state’s surgeon general, however, said: “We recognise that the unknown can be scary, especially for pregnant women.”

In the absence of federal funding to fight Zika, authorities in affected states have scrambled both to contain it and to be seen to be acting to do so.

"This morning we learned that four people in our state likely have the Zika virus as a result of a mosquito bite," Florida governor Rick Scott said on Friday. "This means Florida has become the first state in our nation to have local transmission.

“Florida is taking an aggressive approach. We have worked hard to stay ahead of the spread of Zika and prepare for the worst.”

Of the four new cases, Mr Scott said, two were in Miami-Dade County and two in Broward County. One was a woman and three were men. Health officials believe the infections occurred in a very small area, of about one square mile, just north of downtown Miami.

Despite stepping up the trapping and testing of mosquitos in the area, officials have yet to find an insect testing positive for the Zika virus. Officials are going door to door, offering to test the public. It was announced on Thursday that blood donations have been suspended in the affected area until all current samples can be tested.

A statement from the Florida department of health said: “While no mosquitoes trapped tested positive for the Zika virus, the department believes these [four] cases were likely transmitted through infected mosquitoes in this area.”

Local, state and federal officials were investigating. Federal authorities have confirmed more than 1,600 Zika cases in the US. All patients prior to the four reported in Florida contracted the virus while travelling abroad or through sexual contact with an infected person.

Last week, it was reported that authorities in Florida suspected one infection in Miami-Dade had occurred via local mosquito bite. Mr Scott’s words on Friday suggested a worsening of the problem.

He sought to emphasise, however, that there have been no reported cases of local transmission of Zika in central parts of his state. As every summer, the Orlando area is teeming with visitors from all over the US and the globe, attending theme parks such as Disney World, Universal Studios and SeaWorld.

No vaccine

There is no treatment or preventive vaccine for Zika. In most cases the disease produces mild symptoms, such as headache, feverishness and redness in the eyes; 80 per cent of those infected do not even realise it has happened. But for expectant mothers, Zika can lead to babies being born with serious brain defects and developmental abnormalities, especially microcephaly.

UK experts recently urged expectant mothers to avoid travel to the Olympic Games in Brazil, which has been hard struck by the disease, and parts of the US including Florida.

Florida surgeon general Celeste Philip said on Friday: “We learn more about Zika each day but we recognise that the unknown can be scary, especially for pregnant women. We’re committed to sharing as much as we can as soon as we can.”

Mr Scott advised women in the affected area of Miami-Dade and Broward counties who are pregnant or trying to become pregnant to consult their doctor for advice and Zika prevention kits.

The Centers for Disease Control and Prevention (CDC) has reported more than 400 expectant mothers among US Zika cases. It has also warned of likely outbreaks in southern coastal states as the summer heats up, with Florida, Texas and Louisiana on the frontline.

Texas reported the first case of Zika being transmitted within the US in February, in a case believed to have involved sexual contact.

In Florida, Mr Scott has released emergency funding to provide testing the public, the screening of donated blood in the affected counties, and mosquito testing and abatement measures.

Last month, a bitterly divided US Congress failed to pass $1.1bn in federal funding to combat Zika. In protest at such inaction, Florida Republican senator Marco Rubio called the Zika threat a “full-blown health crisis”, and California Democratic senator Barbara Boxer said the crisis was getting worse, adding: “We need to act now.”

Zika has hit hard in US territories such as Puerto Rico, the US Virgin Islands and American Samoa, with local transmission by mosquitoes common. The CDC has reported that the virus is infecting up to 50 pregnant women a day in Puerto Rico.

Guardian service