Singapore Zika strains’ ‘Asian lineage’ dates back to 1960s

A member of a pest control team in Singapore holds up a vial containing mosquito larvae. (Photo: Reuters)

Two locally transmitted cases of Zika in Singapore had virus strains descended from those circulating in South-east Asia since the 1960s, according to a sequencing study conducted by authorities here.

The Ministry of Health’s National Public Health Laboratory and A*STAR’s Bioinformatics Institute announced their findings at a joint briefing on Thursday (8 September), local media reports said. The two cases come from the Sims Drive-Aljunied Crescent cluster.

“The analysis of the virus found in two locally transmitted cases shows it belongs to the Asian lineage and likely evolved from a strain that was already circulating in South-east Asia,” said both agencies, according to a Channel NewsAsia report.

“Currently there is no evidence from existing studies and from this sequence to indicate whether the differences between these strains and the South American virus correlate with differences in severity or type of disease.”

Long-term studies will be needed to fully understand the virus strains and their impact, they said.

Last Saturday, the health authorities announced that the virus strain in Singapore originates from Asia.

Eight additional cases of Zika were discovered on Wednesday (7 September), meaning that there are currently 283 cases in Singapore.