As cases of the mosquito-borne Zika virus continue to spread across Central and South America, as well as in the Caribbean, health experts predict that it is just a matter of time before the disease spreads within the U.S.
Odds Of Zika Transmission In The U.S.
In a study published in the journal The Lancet on Jan. 14, researchers who conducted a study on how the Zika virus from Brazil would spread internationally found a high likelihood of the virus being transmitted to the U.S.
"In Brazil, we identified airports within 50 km of areas conducive to year-round Zika virus transmission," the researchers wrote in their study. "Traveller volumes were greatest to the USA (2,767,337), Argentina (1,314,694), Chile (614,687), Italy (419,955), Portugal (411,407), and France (404,525)."
How Zika Will Spread
Travelers who go to Zika-affected countries could bring the virus to the U.S, where this could be transmitted to mosquitoes that feed on the blood of those infected. The virus-carrying mosquitoes would then pass along the virus when they feed on another person.
"With the recent outbreaks in the Pacific Islands and South America, the number of Zika cases among travelers visiting or returning to the United States will likely increase," the CDC said. "These imported cases may result in local spread of the virus in some areas of the United States."
Infection contracted after travelling to South America has already been reported in the U.S. The Hawaii State Health Department reported last week of a newborn who tested positive for past Zika infection. The baby's mother lived in Brazil in May 2015 and likely passed the virus to her child.
Other cases in Texas, Illinois and Florida also involved individuals who travelled to countries where Zika was endemic.
Dawn Wesson, from Tulane University School of Public Health and Tropical Medicine, said that there's a good chance that the Zika virus will spread locally this coming summer, based on the pattern observed with other mosquito-borne virus, the chikungunya.
What Happens If Zika Virus Becomes Widespread
Brazil, which currently battles with the virus, offers hints on what could happen if the Zika virus becomes prevalent in the U.S.
Between 2010 and 2014, the South American country only had about 156 cases of babies who were born with microcephaly per year. The congenital condition is marked by abnormal smallness of the head and incomplete brain development.
With the increased incidence of Zika, which was once thought of as a generally harmless illness, the number of newborns with the condition jumped to over 3,000.
To date, microcephaly occurs in two babies per 10,000 live births to about 12 babies per 10,000 live births in the U.S., but these numbers could jump significantly with increased incidence Zika as it is being suspected to cause the birth defect.
With a possible link between the mosquito-borne virus and microcephaly, an outbreak could likely prompt an advisory for women to postpone pregnancy just as Brazilian doctors advise women to avoid getting pregnant.
Experts said that should Zika follows the same migratory patterns as those of other mosquito-borne viruses such as chikungunya and dengue, Hawaii, Florida and Texas could be at risk of an outbreak in the future.