Timor-Leste has recorded its first cases of community transmission of the highly contagious Delta variant of coronavirus, raising concerns by its health ministry about a possible spike.
Genomic sequencing by the Doherty Institute in the first week of August found that of 27 samples taken in the country's Ermera region from people infected with the coronavirus, 12 were of the Delta variant.
Ermera has the highest number of active cases and lowest vaccination rate in Timor-Leste, which borders Indonesia where the Delta variant has been fuelling one of Asia's worst coronavirus epidemics.
Home to 1.3 million people, Timor-Leste has recorded just 11,579 cases and 28 deaths since the start of the pandemic.
About 8.5 per cent of its 1.3 million people have been fully inoculated so far, using the vaccines of AstraZeneca and Sinovac.
Samples from other regions have yet to be tested but public health experts said growing case numbers elsewhere in the country could indicate that Delta was also present there.
Danina Coelho, the government's spokesperson on COVID-19 vaccines, said the Ermera cluster showed how critical it was to boost vaccine coverage.
"The government is very concerned about those cases specifically as the rate of vaccination is very low," she said,
"That's why the government is reinforcing the vaccine campaign."