Geneva, July 25 : The Swiss authorities have recorded 28 cases of infection by the mosquito-borne Zika virus since the beginning of the year, the media reported on Monday.

All the infected people had previously travelled to areas affected by the virus transmitted by the Aedes Aegypti mosquito, which has created pandemics in regions in the South and Central America as well as the Caribbean, Xinhua news agency reported.

Four of the Swiss had travelled to the Dominican Republic while three to Colombia and Martinique, and two to Brazil and Bolivia, a report from the Swiss Federal Office of Public Health said.

The number of infections could be higher, though the data reveals that only one in four infected individuals develop symptoms like fever, rash, joint pain and conjunctivitis.

Though rarely fatal, Zika presents a risk for pregnant women with their unborn babies developing microcephaly, a defect with abnormal smallness of brain.

In 2015, the mosquito-borne virus was detected in Brazil, reporting its first case in May last year.

Zika cases on rise in Switzerland