Health officials are monitoring the spread of Zika virus in other countries, saying Vietnam is also at risk.
The Preventive Health Department said the virus, which has been linked to brain damage in thousands of infants in Brazil, has not been detected in Vietnam.
But it said the spread is possible as the virus’ main vector, Aedes aegypti mosquito, can be found in Vietnam. It is also known for carrying the dengue, yellow fever and Chikungunya viruses.
Travelers can also bring the virus to the country, it said.
It has ordered epidemiology institutes to conduct regular studies in Vietnam.
The Zika virus is now being transmitted in 25 countries and territories in the Americas since the first infection in Brazil was confirmed in May 2015.
Geovane Silva holds his son Gustavo Henrique, who has microcephaly, at the Oswaldo Cruz Hospital in Recife, Brazil, January 26, 2016. REUTERS/Ueslei Marcelino
CNN reported that the number of suspected cases of microcephaly, a neurological disorder in which infants are born with smaller craniums and brains, increased to 4,180 as of Wednesday.
The number of reported deaths of deformed babies rose to 49.
No vaccine or treatment is available. The symptoms are also mild which makes it hard for women to know if they have been infected during pregnancy.