COVID-19 cases rose in several Southeast Asian countries in April-May, driven by JN.1 subvariants (LF.7, NB.1.8), probably due to periodic waves and waning immunity. Authorities are monitoring the situation closely.

Singapore:

• Between April 27 and May 3, fresh COVID-19 cases surged to 14,200, up from 11,100 in the preceding week.

• This marks the first time the nation’s government has released data on COVID-19 case numbers - an action usually undertaken only in concerning situations.

Thailand:

• Reports a significant spike. Gatherings held for the Songkran festival may have contributed to enhanced transmission.

• Almost 70% of cases are associated with the JN.1 sub variants, followed by the previously dominant XEC variant accounts

• 49,065 new COVID-19 cases were reported between May 11-17. This number rose to almost 65,000 new cases between May 18 and 24.

• According to experts, the peak is yet to come.

Hong Kong and Mainland China

• Also experienced an uptick in cases around mid-April and early May.

• According to surveillance data from May 3-10, Hong Kong’s Centre for Health Protection noted that COVID-19 positivity rates in respiratory samples hit a one-year high.

• On May 23, the authority reported early signs of slow down in transmission, but urged citizens to continue to stay vigilant.

• The China CDC also reported that test positivity rates more than doubled in these 5 weeks. China experienced a similar trend last summer.

Taiwan:

• Cases surged by 88% during the week of May 11-17 compared to the prior week.

• The Taiwanese CDC predicts the cases to peak around mid-late June at about 55,000-60,000, which is half of what the country witnessed at the same time last year.

India:

• No significant rise so far.

• Also witnessing a gradual increase. As of May 27, the country had 1010 active cases.

• Kerala accounts for a majority of cases followed by Maharashtra, Telangana, Delhi.

• Authorities are reviewing preparedness measures and are deploying additional resources to ensure the health systems’ ability to respond to the ongoing outbreak.

Variants responsible for this outbreak:

• LF.7 and NB.1.8. Both have evolved from JN.1—the variant used in developing the current COVID-19 vaccine formulation

• The XEC variant was previously dominant in the Southeast Asia region but is now being replaced by JN.1 descendants which are more transmissible.

• These variants are unlikely to be more lethal. Hospitalizations and deaths remain in line with expected rates for the current case numbers.

Causes of rise in case numbers:

• Periodic waves of increase in case numbers, as is observed with most endemic respiratory diseases.

• Waning population immunity.

Response across the region:

• Increased international, national and subnational surveillance.

• Efforts to increase immunization coverage.

• Test kits, Vaccine supplies and capacities of healthcare facilities are being enhanced.

• Notably, the Thai government has made provisions that allow its COVID-19 infected citizens to get free online consultations via three partner applications.