A man who completed 21 days of mandatory quarantine upon returning to China from overseas has been identified as the likely source of a new Covid outbreak. The man underwent 14 days of compulsory hotel quarantine, another 7 days in centralized quarantine and then a further week of health monitoring. He had tested negative for the virus nine times during 21 days of quarantine, before testing positive 37 days after entering China.
Putian’s locally-transmitted epidemic mainly has two chains of transmission – the one relating to Putou Primary School and one relating to Xiesheng shoe-making factory. The total infections from the school increased to at least 15 and at least 10 other infections from the Xiesheng shoe-making factory as of press time.
Preliminary studies suggest the outbreak may be traced to father of a student at the school who recently returned to Putian from Singapore. The person surnamed Lin tested positive on September 10, 38 days after returning from Singapore on August 4, during which he took nine nucleic acid and serologic tests, which were all negative.
In its daily update on Thursday night (July 22), the Singapore Ministry of Health (MOH) revealed that of 1,096 locally transmitted infections over the last 28 days, 484 were fully vaccinated, 333 cases were partially vaccinated and 279 were unvaccinated.
Editors note: 484 out of 1,096 infections is 44 per cent of the total. If you add the 333 partially vaccinated, the percentage of vaccine breakthroughs is nearly 75% of total infections.
There is a significant risk of “vaccine breakthrough” with the Sinovac vaccine, or CoronaVac, with international evidence showing that many who had taken it were later infected with COVID-19, said the Ministry of Health’s (MOH) director of medical services Kenneth Mak on Friday, 18 June 2021.
Associate Professor Kenneth Mak said that Singapore has been assessing the experience of countries such as Indonesia, which has vaccinated a “larger proportion” of the population using CoronaVac.
Of the 36 cases of Delta-AY.1 (mountaineers) variant, 27 cases were known to have a vaccination status within the National Immunisation Management System (NIMS).
“Through routine scanning of variation in Delta a small number of sequences were detected which had acquired the spike protein mutation K417N. Information suggests that there are at least 2 separate clades of Delta with K417N. One clade is large and internationally distributed with PANGO lineage designation AY.1. A second clade found in sequences uploaded to GISAID from the USA. There is limited epidemiological information available at present.
As of 7 June 2021, 63 genomes of Delta with K417N have been identified on GISAID. from Canada (1) Germany (1), Russia (1), Nepal (2), Switzerland (4), India (6), Poland (9), Portugal (12), Japan (13), USA (14).
There are currently 36 cases of Delta-AY.1 in England (35 confirmed sequencing and 1 probable genotyping) plus an additional 10 sequences which include some cases in other UK nations and some genomes for which case data is being sought. The first 5 cases were sequenced on 26 April 2021 and were contacts of travellers to Nepal and Turkey. All these cases were detected in the West Midlands. Cases have been detected in 6 different regions in England (Table 21, Figure 26). The majority of cases are in younger individuals, with 2 cases of age 60 or over (Figure 27). Out of the 36 cases, there were 11 travel associated cases (6 travellers and 5 cases amongst contacts of travellers). Twelve cases have no history of travel or contact with travellers. Countries of travel included red-list countries (Nepal and Turkey), amber-list countries (Malaysia) and green-list countries (Singapore).
Of the 36 cases, 27 cases were known to have a vaccination status within the National Immunisation Management System (NIMS), when linked on NHS number. Of these, 18 cases occurred in people who were not vaccinated, 2 cases in people who had received their first dose within 21 days of specimen date, 5 cases in people who had received their first dose more than 21 days after specimen date. There was a total of 2 cases where there were more than 14 days between the second dose of vaccine and a positive specimen. No deaths have been recorded amongst the 36 cases.”
PHE download – SARS-CoV-2 variants of concern and variants under investigation in England – Technical briefing 15 (PDF)
A total of 78 Covid-19 cases in the current outbreak in Singapore have been vaccinated – many of whom are frontline workers – compared to about 300 unvaccinated cases, said Health Minister Ong Ye Kung. The numbers represent a ratio of about 79 per cent unvaccinated cases versus 21 per cent vaccinated ones. It’s “not quite” true that the situation in Singapore is “getting very bad”, he said.
Singapore is currently battling a fresh wave of B.1.617.2 infections introduced through Changi airport despite strict anti-covid protocols including regular antigen and RT-PCR testing for the workforce. About one quarter of the population of Singapore have been fully vaccinated and over one third have been partially vaccinated. Singapore has only approved the use of the Pfizer and Moderna Covid-19 vaccines for use in the country. It’s a stark warning about the difficulty of controlling the spread of the new variant first discovered in India.
On May 19, the director of Singapore’s National Center for Infectious Diseases, Professor Liang Yuxin, said in an exclusive interview with Singapore’s mainstream media, Lianhe Zaobao, that Singapore’s research shows that the recent local transmission of the mutant new coronavirus B.1.617.2 remains in the respiratory tract of patients in a higher amount. It also stays for longer, causing the virus to spread more easily. A study found that patients infected with the B.1.617.2 virus had a higher amount and discharge of the virus in the respiratory tract than the original, longer time in the body, and a slower rate of decline.
Professor Liang Yuxin said that the lower the circulation threshold, the more viruses in the body. The circulation threshold of a common virus is about 20, while that of a variant virus is 15, so it may be easier to spread. She also said that the recent outbreaks of multiple infection groups in Singapore are all related to the B.1.617.2 variant virus that was first discovered in India.
Eleven out of 18 positive patients were vaccinated, at least 6 are infected with the B.1.617 variant.
AT A GLANCE: The #COVID19 cluster at Singapore’s Changi Airport T3 has grown to 18, with 6 patients testing preliminarily positive for the B1617 variant https://t.co/x5GLRB5m3Z pic.twitter.com/DUwce0tdk9
— CNA (@ChannelNewsAsia) May 12, 2021