El Salvador is urging women in the Central American nation to avoid getting pregnant until 2018 to avoid their children developing birth defects from the mosquito-borne Zika virus which has rampaged through the Americas.The Zika virus is transmitted by the Aedes aegypti mosquito, which is also known to carry the dengue, yellow fever and Chikungunya viruses. Health experts are unsure why the virus, which was first detected in Africa in 1947 but unknown in the Americas until last year, is spreading so rapidly in Brazil and El Salvador.Salvadorean Deputy Health Minister, Eduardo Espinosa, cautioned couples to take necessary precautions."This is why we're recommending to partners to plan their pregnancy. If they decide to get pregnant then take the necessary measures to protect mothers during their pregnancy they cover a large part of their bodies so they are not exposed to the mosquito which could cause Zika and a child with microcephaly," he said.Although research is still underway, significant evidence in Brazil shows a link between Zika infections and rising cases of microcephaly, a neurological disorder in which infants are born with smaller craniums and brains.The Salvadorean government decided to make the announcement because 5,397 cases of the Zika virus had been detected in El Salvador in 2015 and the first few days of this year."This implies a new risk for our population in a way that we need to face, destroying the transmitor of these illnesses. For us to be successful there can't be more than four positive cases for every 100 (patients)," said Civil Protection Minister, Jorge Melendez.Official figures show 96 pregnant women are suspected of having contracted the virus, but so far none have had babies born with microcephaly.In Colombia, which has the second-highest Zika infection rate after Brazil, the government is also advising women to delay becoming pregnant, but only for six to eight months.