Zika virus
Zika virusReuters

The Zika virus, believed to be the cause for hundreds of babies being born with abnormally small heads in Brazil since last year, could have arrived in the south American country during major sporting events such as the 2014 Football World Cup, scientists have speculated. 

Brazil's Memórias do Instituto Oswaldo Cruz medical journal published a study last June which linked the strain of the virus in Brazil to the Asian lineage of the microorganism that was first reported in the Zika virus outbreak in the French Polynesia island in 2013. 

"One plausible hypothesis is the arrival of the new emergent virus during the soccer World Cup in 2014," Brazilian researchers had said in the study. 

While the first outbreak of the Zika virus, which was said to be endemic in parts of Africa and Asia, was reported in the South Pacific in 2007 on the Yap Island, the 2013 outbreak in French Polynesia affected about 11% of the population and spread to other Pacific islands, according to the World Health Organisation

In October last year, a researcher from French Polynesia had written in the Emerging Infectious Diseases Journal of the US Centres for Disease Control and Prevention that the Zika virus may have arrived in Brazil during the Va'a World Sprint Championship canoe race held in Rio de Janeiro in August 2014. The author claimed teams from the four Pacific islands of French Polynesia, New Caledonia, Cook Islands, and Easter Island, all of which had reported cases of the virus, had participated in the event. 

The connection of the current outbreak of the Zika virus across Brazil and 22 other countries in Latin America and the Caribbean comes as concerns grow over this year's Olympic Games, to be held in Rio de Janeiro. 

The organising committee for the Rio Olympic and Paralympic Games has reportedly said it is working with Brazil's health ministry to take steps to minimise risks of the virus spreading, as lakhs of tourists are expected to arrive in the country for the sporting event. 

"The Olympic and Paralympic venues will be inspected on a daily basis during the Rio 2016 Games to ensure there are no puddles of stagnant water and therefore minimise the risk of coming into contact with mosquitoes," Phil Wilkinson, the spokesperson for the Rio Olympic Games, told CNN

On Thursday, the World Health Organisation announced it had set up an Emergency Team to look into the Zika virus outbreak, which it said was "spreading explosively" and could end up affecting nearly four million people this year.