Thirteen Indians have been infected with the Zika virus in Singapore, the Ministry of External Affairs confirmed on Thursday.

The Singapore government informed the Indian authorities on Thursday about the mosquito-borne infection.

The patients, who are showing mild symptoms of the fever, have been admitted in hospitals, the MEA said. 

Identities of the patients have not been revealed. 

Earlier in the day, Chinese authorities confirmed that 21 Chinese nationals were stricken with the Zika virus in Singapore. 

China on Thursday issued an alert against travelling to the island nation.

Chinese Foreign Ministry spokesperson Hua Chunying announced here that they were informed about the situation by the Singapore Health Ministry.