Covid-19 studies being adjusted as local pandemic situation evolves: NCID

SINGAPORE - As the Covid-19 pandemic evolves in Singapore, researchers have been shifting the focus of their studies to understand the clinical features of the virus and immunity response after infection.

These studies, which come under Protect - otherwise known as the Multi-centred Prospective Study To Detect Novel Pathogens And Characterise Emerging Infections - are putting novel pathogens like Sars-CoV-2, the virus that causes Covid-19, under the microscope.

The Protect study is helmed by the National Centre for Infectious Diseases (NCID) and conducted in collaboration with seven public hospitals as well as Duke-NUS Medical School and the Agency for Science, Technology and Research.

Dr Barnaby Young, head of the Singapore Infectious Disease Clinical Research Network at NCID, told The Straits Times that the first study under Protect started in January last year when the first Covid-19 case was detected here.

Since then, more than 50 studies under Protect have been published.

"Initially, there weren't many Covid-19 cases earlier on, so we tried to approach everyone. After that, when cases started to rise, we thought about which group of people we need to understand better, and which types of infections," said Dr Young.

Since the start of the pandemic, the studies have looked at a range of infections, from those with severe disease to those who were reinfected.

One of the studies compared clinical outcomes among people infected with different variants of concern - Alpha, Beta and Delta - to those infected with the original wild-type coronavirus.

The findings suggested that those infected with the Delta variant had a higher incidence rate of severe illness.

The current focus is on breakthrough infections involving 150 individuals who took mRNA vaccines.

To have a clearer understanding of immunity among those who have been vaccinated against Covid-19, NCID also coordinated a sub-study under Protect.

The Singapore Covid-19 Vaccine Immune Response and Protection Study (Scope) started in January this year.

For Scope, researchers recruited a wide spectrum of people to understand how their immunity wanes or improves over time, and how this changes with different vaccines.

The study, which is ongoing, covers individuals who took the Pfizer-BioNTech, Sinopharm or Sinovac vaccines, said Dr Young.

Aside from looking at patients from different age groups, researchers studied the immunocompromised and those who received three doses of a vaccine as part of their primary vaccine series.

The Scope study is also looking at individuals who have recovered from Covid-19 and received one Pfizer jab, and those who had one Pfizer jab followed by two doses of Sinovac due to allergic reactions, added Dr Young.

The team is also looking to recruit those who took either the Sinopharm or Sinovac vaccine as a booster after receiving two doses of an mRNA vaccine.

"We're looking in more detail about the exact parts of the virus that the antibody binds to, and how cellular immunity is going to be different across the Sinovac, Sinopharm and mRNA vaccines," he added.