A genetics study say that the Zika virus may have arrived in the American grounds by 2013, a year before the virus was reported in Brazil.
In a study published in the US journal Science, scientists from Britain’s University of Oxford and Brazil’s Evandro Chagas Institute sequenced seven genomes of the Brazilian Zika virus, including one fatal adult case and one newborn with the birth condition microcephaly, Xinhua reported.
The study results proved that the virus had a unanimous entry into the American bloodstream, sometime between May and December of 2013, contrasting it to the first discovery of the disease only by May 2015 in Brazil.
The researchers also looked at airline data and found this timing coincided with an increase in air passengers to Brazil from Zika-endemic areas, and also with reported outbreaks in the Pacific Islands.
One hypothesis of a group of researchers is that the virus might have been first introduced during the Confederations Cup soccer tournament, in which French Polynesians participated from Tahiti.
“Although the American outbreak virus is most closely related to a strain from French Polynesia, it’s also possible that Zika was introduced separately to the Americas and French Polynesia from South East Asia,” said Professor Oliver Pybus, a biologist at the Oxford University’s Department of Zoology.
The Zika virus is transmitted to humans mainly through the bite of an infected Aedes mosquito.
The main worry being that the virus is linked to microcephaly in infants, but yet to be proved though.