NBC News, in a Jan. 16 piece, reported that a newborn infant in Hawaii has been confirmed to have microcephaly after its mother suffered a Zika infection while pregnant. The illness was contracted in Brazil, last May. That outbreak has now moved into much of the Americas and could reach the continental United States.
The Examiner spoke with Dr. Scott Weaver from the Galveston National Laboratory about the spreading Zika outbreak on Jan. 18. He stated that the Zika outbreak in the Americas has “caught a lot of people by surprise.” While Zika illnesses have been seen in Africa, Asia and in the Pacific, the appearance in Brazil and its rapid spread to infect hundreds of thousands is new.
Zika is transmitted by two species of the Aedes mosquito, and both are found throughout tropical and sub-tropical North and South America. These mosquitoes have habitat along the Gulf Coast of the United States and through much of the southern U.S.
Dr. Weaver described the cycle quite simply. A female Aedes mosquito bites a person infected with Zika. The mosquito develops an infection and then bites an uninfected human. “It only takes one bite.”
The evidence is mostly circumstantial concerning the link between maternal Zika infections and microcephaly in newborns, Weaver said. The massive Zika outbreak in northeastern Brazil coupled with over 3,500 reports of microcephaly from that nation is too coincidental to ignore. Up until now, reports of microcephaly and Guillain-Barre Syndrome linked to Zika have been rare.
“Most people don’t even know that they were infected,” he said. In other cases, the person is infectious but has an initial period where they do not experience symptoms. In either case, they can infect mosquitoes that bite them. Weaver believes that the Zika outbreak likely began with one infected person arriving in Brazil and then being bitten.
Yellow Fever is another viral illness that can be spread by Aedes mosquitoes. Dr. Weaver points out that Yellow Fever became endemic to the Americas after it developed an animal reservoir. The virus began infecting New World non-human primates and moved out of reach of mosquito control efforts around humans. He believes that it is possible that Zika and chikungunya could also find non-human reservoirs in the future.
Weaver pointed out that the Summer Olympics will be held in Brazil this year. Zika could pose “a major problem.” Attendees might easily contract Zika and carry it home to nations where the illness is unknown.
On Jan. 15, the Centers for Disease Control and Prevention (CDC) issued “interim travel guidance” about Zika infections for 14 nations and territories in the Americas. “Out of an abundance of caution” the agency recommends that pregnant women and those trying to become pregnant avoid or postpone travel to areas where Zika infections are occurring. The CDC does point out that far more research is needed about the effects a maternal Zika infection could have on the fetus.
Scott C. Weaver, M.S., Ph.D. is a Professor in the Departments of Pathology and Microbiology & Immunology at the University of Texas Medical Branch, Director of the Institute for Human Infections and Immunity and Scientific Director of the Galveston National Laboratory.