Zika virus: Pregnant women warned to stay away from Rio Olympics

Health officials have warned pregnant tourists to avoid travelling to Brazil for the Rio 2016 Summer Olympics after an outbreak of the Zika virus which causes babies to be born with unusually small heads and brains.

Researchers have linked the rise in neurological disorder Microcephaly to the mosquito-borne disease.

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The virus has now reached 14 other countries in Latin America and the Caribbean.

Marcos Espinal, head of the Pan American Health Organization's communicable diseases department, told the Daily Mail that "travel restrictions will not stop the spread of Zika".

He said: "It's a mosquito that is endemic in the whole of Latin America and the Caribbean, and the population of the Americas was not exposed to the virus, so there's no immunity to it."

The BBC reports that officials in Colombia, Ecuador, El Salvador and Jamaica have warned women not to fall pregnant.

Brazil says the number of babies born with suspected microcephaly has reached 4,000 since October.

Meanwhile, three British travellers have been diagnosed with the Zika virus after returning to the UK from South and Central America.

In a statement, Public Health England said: "ZIKV does not occur naturally in the UK. As of 18 January 2016, three cases associated with travel to Colombia, Suriname and Guyana have been diagnosed in UK travellers."

Public Health England says the virus "is not spread directly from person to person" and "if a person acquires ZIKV abroad and becomes ill on their return to the UK, they can't pass the infection on to anyone else."