MIAMI – Infectious disease experts say Florida's warm climate, poverty and mosquitoes present an ideal setting for the Zika virus to spread.
There was alarm Thursday when the World Health Organization convened an emergency committee to deal with the virus. WHO's director general Margaret Chan said the virus was in 23 countries in the Americas and was "spreading explosively" across the hemisphere.
She added: The current weather patterns could mean mosquito populations were going to spread. And there are no vaccines. WHO's emergency committee will meet on Monday in Geneva.
"The level of alarm is extremely high," Chan said.
The Centers for Disease Control and Prevention identified 31 cases in the U.S. All of the cases involved patients who had traveled to areas where the virus was rampant. Florida confirmed its first cases in January. Two had traveled from Miami-Dade to Colombia, where as of this week there were some 13,800 cases.
"We expect an expansion similar to what we had with the chikungunya virus last year, to finish between 600,000 to 700,000 cases," Colombian health minister Alejandro Gaviria said Wednesday.
The other Florida patient traveled from Hillsborough County to Venezuela. On Thursday, Venezuela's health minister Luisana Melo said on state television that there were 4,700 suspected cases and the country was already starting fumigation operations.
After a mosquito bite, the Zika virus can cause fever, muscle pain and skin rashes on some people. Scientists are also investigating its link to a congenital condition associated with incomplete brain development and also to a rare disease that can lead to paralysis.
Aside from Florida, Texas, Arkansas, Iliniois and New Jersey have confirmed Zika cases. The Centers for Disease Control and Prevention was working with Brazilian health officials. All of the cases involved patients who traveled overseas.
The virus first concerned officials in 2013 when some 28,000 in French Polynesia were diagnosed. About a year later, the virus spread to Brazil with about 270 cases.
The last time WHO's Public Health Emergency of International Concern triggered a coordinated international response to stop a disease was August 2014 with Ebola. This was only a few months after the reemergence of polio May 2014. In 2009, it was done for the H1N1 influenza epidemic.
10 facts about the Zika virus
1. Aedes aegypti mosquitoes, which usually bite in the morning or evening, are the vector.
2. The virus does not transmit from person to person
3. Symptoms of mild fever, skin rash and conjunctivitis last two to seven days
4. There is no specific treatment or vaccine available
5. Virus was first identified in Uganda in 1947 and in humans in 1952
6. Virus outbreaks were first reported in 2007 in the Pacific and 2013 in French Polynesia
7. During outbreaks, health authorities may advise spraying insecticides
8. More than 13 countries in the Americas have reported Zika virus infections
9. Doctors require a blood sample to diagnose the virus
10. The best form of prevention is protection against mosquito bites