Singapore(Amazing)- Covid 19 antibodies CSI now allows MOH to determine who likely infected who

[ohmrlobalobayeh]

SINGAPORE: In a world-first, a research team at Duke-NUS Medical School established a link between two COVID-19 clusters in Singapore via serological testing on two cases, the Ministry of Health (MOH) announced on Tuesday (Feb 25).

The lab tests showed that a couple, cases 83 and 91, were infected with the coronavirus. The couple are linked to the Life Church and Missions Singapore and came into contact with cases 8 and 9, a couple from Wuhan.

Cases 83 and 91 then passed the infection during a Chinese New Year gathering on Jan 25 to Case 66, who works at Grace Assembly of God church and has been determined by MOH to be the primary case in that cluster.

READ: Chinese New Year gathering identified as missing link between COVID-19 church clusters

"This meant that cases 83 and 91 likely got infected from case 8 and 9, and went on to pass the infection to case 66 at the Chinese New Year gathering,” the health ministry said.

Cases 83 and 91 had no symptoms at the time of the investigations, the ministry explained.

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Records showed that case 91 had gone to Sengkang General Hospital the day after the gathering with symptoms consistent with COVID-19. Case 83 had also been unwell end-January, and repeatedly sought treatment at a GP clinic.

The MOH epidemiology team arranged for cases 83 and 91 to be tested at the National Centre for Infectious Diseases, including the use of serological tests developed by the Duke-NUS team.

Serological tests are tests that look for antibodies in blood samples.

"The test results confirmed they had earlier been infected with COVID-19," MOH said.

HOW THE TESTS WERE USED

According to MOH, Duke-NUS had cultured the COVID-19 virus in less than a week after Singapore confirmed its first case.

"Using the virus and genetic material derived from the virus, the research team had then rapidly developed several specific lab tests to detect the virus-specific antibodies for contract tracing and other applications," said MOH.

MOH said the lab test currently used to confirm the COVID-19 infection is a molecular test called the Polymerase Chain Reaction (PCR) which detects the the presence of viral generic material in a biological sample obtained from a patient.

The drawback with this test, said MOH, was that it would not work if the patient had recovered and the body's immune system has cleared the virus.

"However, the immune system produces antibodies in response to the infection. The virus specific antibodies will stay with the recovered patient for longer periods of time, which could be at least for several years," said MOH.

Using two different antibody testing platforms (virus neutralisation assay and ELISA assay), the Duke-NUS team proved that cases 81 and 93 were infected with COVID-19 in late January 2020, as they had very high levels of the virus-specific antibodies in the their blood.

"This result was a significant piece of evidence which confirmed the links between the church clusters and the two Wuhan travellers," added MOH.

Source: CNA/rw(mi)

 

[ohmrlobalobayeh]

SINGAPORE - The mystery behind Singapore's largest coronavirus infection cluster - the Grace Assembly of God church - has been solved, using a new test that is able to detect past infections even in recovered patients.

Using a serological test developed by Singapore's Duke-NUS Medical School, contact tracers from the Ministry of Health and the police were able to track the infection to two travellers from Wuhan, who were Cases 8 and 9.

The Wuhan couple were linked to The Life Church and Missions cluster, a Chinese New Year family gathering in Mei Hwan Drive, and finally to the Grace Assembly of God, which to date is linked to 23 cases.


This is believed to be the first time clusters have been linked using serological tests.

The new test - which is done on a blood sample - can be used on patients who have recovered. The lab tests currently used to confirm infections, known as polymerase chain reaction (PCR) tests, detect the presence of viral genetic material in biological samples obtained from a patient, such as a saliva swab. It thus will not work if the patient has recovered.

The new test works by detecting antibodies the body produces in response to an infection. These antibodies can stay in the body for several years.

The Health Ministry said on Tuesday (Feb 25) that the Grace Assembly of God church cluster began with Case 66, a 28-year-old Singaporean who works at the church and also attended a family gathering in Mei Hwan Drive.

"Case 66 had reported onset of symptoms on Jan 29 - the earliest in the cluster - and had gone to work at Grace Assembly of God while symptomatic," said the ministry.

To determine how Case 66 had been infected, contact tracers investigated the locations he had visited and the people he had close contact with.

Investigations led them to a married couple, cases 83 and 91, who attended the same Chinese New Year family gathering and were also at the Life Missions church on the day the Wuhan couple - cases 8 and 9 - were there.

The couple had no symptoms at the time of the investigation, but records showed both had earlier sought medical treatment.

Case 91 had gone to Sengkang General Hospital on Jan 26 with symptoms consistent with Covid-19, while Case 83 had repeatedly sought treatment at general practitioner clinics at the end of January.

Based on this finding, the ministry's epidemiology team arranged for cases 83 and 91 to be tested at the National Centre for Infectious Diseases, including using serological tests developed by researchers from the Duke-NUS Medical School.

Their tests - conducted while they were well - confirmed they had earlier been infected.

"This meant that cases 83 and 91 likely got infected from cases 8 and 9 (Chinese nationals from Wuhan), and went on to pass the infection to Case 66 at the Chinese New Year gathering on Jan 25," said the ministry.

"Case 66 subsequently passed the infection to his colleagues at Grace Assembly of God."














so according to article:

Wuhan couple, Case 8 and 9(attended Life Mission Church, a local church in Singapore) = Patient Zero(s)

above infected below:

Case 83 and 91(Singaporean couple who also attended Life Mission Church) = Patient One(s)

above infected below:

Case 66 (Grace assembly Church(another local church) staff who attended CNY gathering with Case 83 and 91) = Patient Two

and Case 66 is responsible for igniting a long chain of infections in singapore