The Covid-19 virus that caused the recent spike in Hong Kong could have come from Philippines sailors and flight crews from Kazakhstan, DNA sequencing shows.
Twenty-six samples from patients in the “third-wave” epidemic could be split into three types, said Gilman Siu, an associate professor at the health technology department of Hong Kong Polytechnic University.
Of the 26, 19 were found to have a DNA sequence similar to the virus found in the Philippines. These cases were found in districts across Hong Kong.
Siu said the origin could be ship crews who came from the Philippines but were exempt from the city’s 14-day quarantine and virus test requirements.
Between July 1 and 27, 76 people coming from the Philippines were identified as infected. At least 15 of them were sailors. The rest were domestic and other workers, who were required to be quarantined and tested.
Another group had a similar DNA pattern to the coronavirus found in patients from Kazakhstan. These patients stayed at the Crowne Plaza Hong Kong Causeway and lived in Leighton Hill. Siu said this transmission chain could be linked to flight crews from Kazakhstan who were also exempt from quarantine and virus tests.
The last group of samples was collected from patients in Sai Kung with unknown sources.
After local cases re-emerged in Hong Kong from July 5, medical experts said people in 33 categories, including sea and flight crews, who were exempted from compulsory quarantine could have brought the virus to the city.
Since February, Hong Kong’s Security Bureau has allowed more than 290,000 incoming travelers to be exempt from quarantine and testing by giving them notifications of medical surveillance.
The government announced on July 8 that all incoming sea and flight crews must be tested but on July 19 it rejected medical experts’ criticisms that the quarantine exemptions created loopholes linked to the latest wave.
On Tuesday, Health Secretary Sophia Chan admitted that the exemptions had caused the recent virus outbreak. From Wednesday, sea and flight crews were required to be quarantined for 14 days, unless they could present a negative test certificate.
David Hui Shu-cheong, chairman of the department of medicine at the Chinese University of Hong Kong, said the government had never consulted its medical expert team about exempting sea and flight crews from quarantine and tests.
Keiji Fukuda, community medicine professor at the University of Hong Kong, said the government had not held a meeting with medical experts since July 11.
On Wednesday, the Center for Health Protection said the number of confirmed cases recorded a high of 118, made up of five imported cases and 113 local infections, within 24 hours on Tuesday. Among the local cases, 67 could be linked to previous cases while the remaining 46 had unknown sources. Most local patients were infected at home and in social gatherings while some were infected in offices and restaurants.
Hong Kong recorded an eighth straight day of triple-figure infections with the total number of cases reaching 3,002. Two more people died in the 24 hours up to Wednesday noon, bringing the total fatalities to 24.
Since the weekend, a new threat has emerged as more than a hundred patients have had to stay at home due to insufficient hospital beds. Before the “third wave” outbreak, all Covid-19 patients could be treated in hospital.
However, as of Sunday, about 100 patients were still waiting to be sent to hospital. The Hospital Authority said the situation was not satisfactory. It hoped patients could wait patiently.
Fashion designer William Tang told local media Tuesday that he was sent to a hospital four days after he tested positive. His wife and domestic worker had been sent to quarantine centers earlier.
A 40-year-old woman, who lived in Wing Ning Tsuen in northern New Territories, tested positive on July 22 but could only be admitted to hospital on July 25 after she called an ambulance. Her two sons were then infected while her husband was sent to a quarantine center. A domestic worker stayed at home.