SINGAPORE: A worker who assisted a family from South Asia last month could have been the infection source that led to 43 staff members at Changi Airport testing positive for COVID-19.
"Phylogenetic testing results for an initial batch of COVID-19 positive airport workers were found to be similar and of the B1617 variant, indicating that they originated from a common source," the Civil Aviation Authority of Singapore (CAAS) and Changi Airport Group (CAG) said in a joint media release on Friday (May 21).
“Preliminary investigations indicate that the initial transmission could have occurred through an airport worker who was assisting a family from South Asia, who arrived in Singapore on Apr 29, 2021 and were subsequently found to be positive for COVID-19 through their on-arrival tests."
As of Thursday, a total of 43 airport workers - including the worker who helped the family - have tested positive for COVID-19.
Most of these cases "peaked around May 13", said CAAS and CAG in their release, and none are in serious condition or require treatment in the intensive care unit.
Ten were tested during a special testing operation while 33 were detected while serving quarantine orders, through earlier rostered routine testing, through the Ministry of Health’s (MOH) voluntary testing operation for visitors to Terminal 3, or upon seeking medical treatment from a general practitioner.
Further investigations by MOH and CAAS are ongoing.
A total of 100 COVID-19 cases have been linked to Changi Airport as of Thursday, making it the country’s largest active cluster.
Authorities said last week that a number of those cases were congregated around a zone that receives travellers from higher-risk regions, including South Asia.
READ: Changi Airport terminals and Jewel to remain closed to public; additional COVID-19 testing for 'very high-risk' arrivals
CAAS and CAG added that close to 19,000 frontline and office workers in the Changi Airport Passenger Terminal Buildings and Jewel Changi Airport were tested from May 9 to May 20 during its special testing operations.
All workers at Terminal 1 and Jewel tested negative for COVID-19 while 10 workers from Terminal 3 tested positive.
“Out of an abundance of caution, all airport workers who were working around T3 Basement 2 who had tested negative for COVID-19 in their first test, have been rostered to take an additional COVID-19 test since May 20, 2021 – these results are pending,” they said.
CAAS and CAG also announced on Friday that Changi Airport's passenger terminals as well as Jewel will remain closed to the public until the end of the Phase 2 (Heightened Alert) period, while all arrivals from "very high-risk" countries and regions will undergo additional COVID-19 testing.
According to CNA's study of data published on MOH’s website, 43 out of the 100 cases linked to the cluster so far have received one or two doses of the COVID-19 vaccine.
A comparison between those who have been vaccinated and those who have not, revealed that there were 12 more symptomatic cases in the unvaccinated pool. Common symptoms include fever, cough and runny nose.
Twenty-four patients linked to the cluster preliminarily tested positive for the B1617 variant, which was first detected in India. Half of them were not vaccinated.