GEORGE TOWN: Experts are calling on government officials to refrain from using the term “herd immunity” as it is misleading under the present circumstances.
They said that with more infectious Covid-19 variants on the horizon and some people refusing to get vaccinated, herd immunity was virtually impossible to achieve.
Herd immunity occurs when a large part of a community becomes immune to a disease.
Universiti Sains Malaysia’s (USM) infectomics cluster lead Muhamad Amir Yunus said the right term to use now would be “path to normality”.
He said there were several factors that made herd immunity impossible at this point, including the ever-changing SARS-CoV-2 virus that caused Covid-19 and an uneven vaccine rollout across the world.
“Some countries have very high rates of vaccination and some very low. This would have an impact on whether we can wipe out the virus and come out of the pandemic,” he told FMT.
“Moreover, the vaccines being handed out now are only for adults and teens. We don’t know how children in primary school would be able to take the vaccine and stay shielded from the virus.
“Also, strong resistance from anti-vaxxers and the vaccine-hesitant will further complicate efforts towards herd immunity.”
Amir’s USM colleague, Kumitaa Theva Das, said herd immunity was a misnomer as data show that those vaccinated may not retain the initial immune levels after six months, especially in the presence of more infectious strains such as Delta.
She said this and other factors would make herd immunity impossible, and noted that even in high-vaccination territories such as Israel, Singapore and Sarawak, case numbers remained high.
“Delta has changed many things, including how we deal with this virus,” Kumitaa said. “While there is talk about Covid-19 being endemic, some SOPs must be kept and we are likely to need yearly vaccine shots to keep the worst effects at bay.”
Seasonal illness
Monash University Malaysia’s Vinod Balasubramaniam said Covid-19 was something that one would have to endure over the long run.
He said this was because people who had been vaccinated continued to violate SOPs, thus increasing their chances of contracting the virus. That alone made herd immunity impossible.
Vinod said the lack of conclusive data on waning immunity, and logistics and procurement problems in the future would also make the virus impossible to eradicate.
Covid-19 would become a seasonal illness, he said, along with other human coronaviruses already in circulation and which also caused upper respiratory infections.
“Getting Covid-19 is unlikely to give you lifelong immunity. But even if you are infected again, the second infection will likely be less serious,” he said.
“We might need booster doses against variants and to provide optimal immunological memory against the disease.”