UNITED NATIONS – Florida is ground zero in the United States for the entry of the Zika virus, which can remain viable for one week in a donated unit of blood and, therefore, be transmitted by sexual intercourse, sharing drug needles or transfusion, according to a prominent epidemiologist.
Dr. Kenneth Ratzan, the chief of infectious diseases at Mt. Sinai Hospital in Miami Beach, Florida, said his state’s “warm climate and mosquitoes present an ideal setting for the Zika virus to spread.”
Florida’s first of three confirmed case of the Zika virus, contracted overseas, was in January.
“Because South Florida in an entry point for many Latin American travelers, South Florida in particular could see locally-transmitted cases of the virus by the summer,” said Ratzan, who also is on the faculty of the Miller School of Medicine at the University of Miami.
Ratzan confirmed the Aedes aegypti mosquito, found in the southeastern United States, is the species of mosquito responsible for transmitting the Zika virus. It’s the same mosquito that transmits Chikungunya, a disease WND has reported has been carried into the United States by travelers and by illegal immigrants entering the country from south of the border.
According to the Centers for Disease Control in Atlanta, the Zika virus has been reported in Central America, South America, Mexico, the Caribbean and in Puerto Rico.
Asked to comment on a report Tuesday that health officials believe a person in Texas has become infected with the virus through sexual activity, Ratzan confirmed it’s possible.
He cited a study published by the journal Emerging Infectious Diseases documenting the Zika virus was transmitted sexually by an American scientist who had worked in Senegal to his wife, who had never been to the country.
Ratzan said he has learned that the virus can remain viable for one week in a donated unit of blood.
Infected people walk virus into U.S.
“The normal way the Zika virus is brought into the United States is that a traveler gets infected with the virus in a country at risk, like Brazil,” Ratzan pointed out.
“The infected person brings the virus into the United States in their blood stream. Then a mosquito feeds on that person and transmits the virus to another person via a mosquito bite.”
In November 2014, WND reported dengue hemorrhagic fever had joined Chagas disease, Enterovirus D-68 and Chikungunya – as well as drug-resistant tuberculosis and malaria – on the list of diseases brought to the United States by illegal aliens, including through the several surges of “unaccompanied minors” that the Obama administration had admitted without health screening.
Ratzan noted that one problem in controlling the Zika virus is that 80 percent of those infected display no symptoms of the disease.
“Someone could travel, be relatively asymptomatic, but yet have the virus and get sick only when they got back to the United States,” he said. “The same person could also be bitten by a mosquito while they are yet asymptomatic [and] transmit the Zika virus even though they don’t yet realize they are infected with the Zika virus.”
Ratzan said it will be difficult “to address control measures by quarantining or isolating infected patients, because only 20 percent are symptomatic, and of those 20 percent, not all are going to seek medical help and not all of the 20 percent showing symptoms are going to be properly diagnosed as having the Zika virus, even if they do seek medical help.”
Also, Ratzan stressed that the mosquito must be of a particular species to transmit the disease.
“We know for certain the Zika virus is transmitted by the Aedes aegypti mosquito,” he affirmed. “There is another species, the Aedes albopictus, is here in the United States, and we know it can transmit both dengue fever and the Chikungunya virus, and we suspect it may be a possible vector for transmitting the Zika virus.”
Mosquito control best preventative
“The species of mosquito that transmit dengue fever, Chikungunya and the Zika virus, are already here in the United States,” Ratzan continued. “We just don’t yet have enough people infected with those diseases to serve as a reservoir for the mosquitoes to pick up and transmit the disease by feeding on those already infected, ready to transmit by a mosquito bite the disease to someone who is susceptible.”
Ratzan said the best way to deal with the Zika virus is mosquito control.
“We have a strong public health infrastructure in the United States, and we need to control the Aedes aegypti mosquito here, but we also have to control the Aedes aegypti mosquito in the countries where the Zika virus is in danger of becoming an epidemic,” he said.
One form of mosquito control, he said, is to spray chemicals that kill the mosquitoes that have hatched and another is to eliminate the sites where the mosquitoes breed, including pools of standing water.
Asymptomatic mothers can transmit microcephaly
On Monday, in an international press conference in Geneva, Switzerland, the WHO director-general, Dr. Margaret Chan, announced the outbreak of the Zika virus in Brazil had been declared an international health emergency because of a suspected causal relationship.
The virus is responsible for a surge in a birth defect called “microcephaly” in which a pregnant woman infected with the virus produces a fetus with an abnormally small head and, in some cases, potentially debilitating brain damage.
In Brazil, more than 3,500 cases of microcephaly – more than 20 times the norm – have been reported during the current outbreak.
Ratzan admitted there was much about how the Zika virus transmits microcephaly to an unborn child that medical science does not yet know.
“We don’t know for sure in what trimester the fetus has to be exposed to the Zika virus to develop microcephaly,” he conceded. “We think the fetus has to be exposed early, because microcephaly involves development of the brain. We need to know, if a mother is symptomatic, does this make it more likely the virus will be transmitted to a fetus than if the mother is asymptomatic?”
He noted that the WHO emphasized that while there appears to be a correlation in Brazil between an outbreak of the Zika virus and the incidence of microcephaly among newborn infants, medical science has yet to establish a causal relationship between the Zika virus and microcephaly in newborn children.
“There is much that yet remains to be worked out between the Zika virus and the risk of infection to the fetus,” he stressed. “It is still too early to come up with anything definitive.”
Ratzan clarified that microcephaly can occur for other reasons.
“Even in Brazil, not all instances of microcephaly in the current spike in cases have been linked definitively to the Zika virus,” he said.