Aussie study shows role of IgA antibody in neutralizing COVID

Staff check a client at a drive-through COVID-19 testing clinic at Bondi Beach in Sydney, Australia on Jan 8, 2022. (MARK BAKER / AP)

SYDNEY / MANILA / HANOI / SINGAPORE / YANGON / VIENTIANE – Immunoglobulin A (IgA) contributed to the neutralizing antibody response of wild-type COVID-19 virus, according to an Australian study published in the Clinical and Translational Immunology journal.

Conducted by researchers from Australia's Peter Doherty Institute for Infection and Immunity (Doherty Institute), the University of Melbourne and Walter and Eliza Hall Institute of Medical Research, the study published on Sunday compared different antibody responses to the virus in blood serum from 41 people who had recovered from COVID-19.

"In simple terms, we've deconstructed blood in our lab to measure its ability to smother the virus and to activate immune cells to kill SARS-CoV-2," said Samantha Davis, lead author and PhD researcher at the Doherty Institute.

"While we knew that IgG (Immunoglobulin G) is very important in the antibody response to clear the virus, we discovered that IgA also plays a key role in neutralizing it in most people," Davis noted.

According to a statement by the Doherty Institute on Monday, following COVID-19 infection, virus-specific antibodies are generated, which can both neutralize the virus and clear the infection. While much has been said about the importance of IgG antibodies for protection and control of the COVID-19 virus, the role of IgA antibodies has been relatively neglected throughout the pandemic.

Amy Chung, co-author and laboratory head of the Doherty Institute, said the new study opened door to new approaches for the development of future vaccines against COVID-19.

"Our findings are particularly important as IgA is the most abundant antibody present in the mucosa of our respiratory tract, which is the main route of virus infection," said Chung. "This means if we're able to specifically make these antibodies at these vulnerable sites, we now know that we can induce a robust immune response to protect against the virus."

Researchers also pointed out that the convalescent IgA neutralizing response is highly heterogenous between individuals. Dissecting the IgA response in the context of vaccination and to variants of concern is essential to further understanding the antibody in a protective polyclonal antibody response, according to the study.

A man receives a dose of China's Sinopharm COVID-19 vaccine at a vaccination center in Vientiane, Laos, June 17, 2021. (PHOTO / XINHUA)


The Lao Health Ministry called on people to get a booster shot of COVID-19 to strengthen their immunity as there is a high risk of a further outbreak.

Head of the Vaccine Preventable Disease Division under the ministry Kongxay Phounphenghack told a press conference in the Lao capital Vientiane on Monday that many people are reluctant to have a third dose of a COVID-19 vaccine because they believe it is unnecessary.

However, a booster vaccination offers significant added protection against the virus, he added.

The health authorities are warning everyone in Laos to be alert as there is a high risk of a further outbreak, given that a large number of Lao workers are returning from other countries, where COVID-19 infections are spiraling.

Statistics show that at least 15 percent of returning workers are carrying the virus. This poses the threat of a widespread outbreak in Laos, said Kongxay.

The health authorities are expediting the vaccination program as Laos strives to prevent a further outbreak of the virus.


Malaysia recorded 1,737 new COVID-19 infections as of midnight Monday, bringing the total tally to 4,883,796, according to the health ministry.

There were one new imported case and 1,736 more local transmissions, data released on the ministry's website showed.

Three new deaths have been reported from the pandemic, taking the death toll to 36,447.

A woman receives a shot of China's Sinopharm COVID-19 vaccine in Yangon, Myanmar, Aug 29, 2021. (PHOTO / XINHUA)


Myanmar confirmed 139 new cases of COVID-19 in the past 24 hours, bringing the tally to 630,742, according to the Ministry of Health on Monday.

The ministry said in a statement that the health authorities tested 8,920 people for COVID-19 in the past 24 hours, and the daily positivity rate was 1.56 percent.

The death toll from COVID-19 in the country reached 19,477 on Monday as one new death was reported in the past 24 hours, the ministry said.

A man shops for face masks in Divisoria, a local shopping district in Manila on May 17, 2022. (JAM STA ROSA / AFP)


The Philippines reported 1,334 new COVID-19 infections on Monday, bringing the total number of confirmed cases in the Southeast Asian country to 3,995,967.

The Department of Health said the number of active cases dropped to 22,850, while 35 more patients died from COVID-19 complications, taking the death toll to 63,814.

Metro Manila, the capital region with over 13 million people, tallied 367 new cases.

A notice warning people not to gather in groups larger than five persons as part of restrictions to hald the spread of the coronavirus is displayed at Raffles Place financial business district in Singapore on Jan 4, 2022. (ROSLAN RAHMAN / AFP)


Singapore reported 3,627 new cases of COVID-19 on Monday, bringing the country's total tally to 2,067,790.

Of the new cases, 357 were detected through PCR (polymerase chain reaction) tests and 3,270 through ARTs (antigen rapid test), according to statistics released by the Ministry of Health.

Among the PCR cases, 342 were local transmissions and 15 were imported cases. Among the ART cases with mild symptoms and assessed to be of low risk, there were 3,133 local transmissions and 137 imported cases.

One more death from COVID-19 was reported on Monday, taking the total death toll to 1,663.

Passengers wait for transportation outside the arrival hall of Noi Bai International Airport in Hanoi on March 15, 2022, as Vietnam announced the return of a visa exemption policy for 13 countries in an effort to kickstart its tourism sector. (NHAC NGUYEN / AFP)


Vietnam recorded 546 new COVID-19 cases on Monday, up by 388 from Sunday, according to its ministry of health.

All the new cases were locally transmitted, said the ministry.

The newly reported infections brought the total tally to 11,497,533. The country reported two new deaths from the pandemic in the southern Tay Ninh province on Monday, bringing the total fatalities to 43,161