The transmission of the highly contagious Omicron variant of coronavirus may subside at the end of this month, experts said, hoping that it may leave behind an extremely high level of immunity.

They also said the widespread Omicron infection may help Bangladesh and most countries in the world finally attain the much-talked-about herd immunity nearly two years into the Covid pandemic.

Talking to UNB, leading public health experts Dr Bijon Kumar Sil, Dr Be-Nazir Ahmed and Dr MH Chowdhury Lenin said the immunity gained through the Omicron infections may work as a shield against future same type of variants of the coronavirus for some time.

But they are not sure about how durable this immunity would be or how well it would work if a different type of Covid strain emerges in the days to come.

Blessing in disguise

Noted microbiologist Dr Bijon Kumar Sil, head of microbiology department at Gono University, said the antibody produced by Omicron can neutralise Delta and all other previous strains of Covid-19. "But the antibody created by the Delta variant can't neutralise Omicron. "So, the Omicron is producing a very strong antibody which may resist the future variants of the virus, except any unusual one.

He said not only Bangladesh but also almost all countries in the world are going to attain natural herd immunity because of massive exposure to the omicron variant.

Dr Bijon said over 40 percent of people across the world had natural or artificial antibodies before the emergence of Omicron. "As Omicron has spread rapidly all over the world, hardly anyone will remain without a natural antibody with the ebbing of its wave. So, the new variant that may arrive in the future is unlikely to spread fast."

"Most people in our country have already got infected by Omicron and the rest will also contract it in the days to come. So, we're reaching towards the natural herd immunity against the virus. We could not do it by vaccines as we can't vaccinate underage children," the expert said.

He describes Omicron as a blessing in disguise as he thinks it may help get rid of the deadly coronavirus through the immunity the variant is leaving behind.

Dr Be-Nazir Ahmed, former director of Communicable Disease Control (CDC) at the Directorate General of Health Services (DGHS), said the virus that spreads fast also ends quickly. "This is happening in the case of Omicron. If any unusual thing doesn't happen, the community transmission of Omicron will stop by this month. It means we'll achieve herd immunity by this time."

Once herd immunity is attained, he said if a similar variant emerges in the future, it will not spread quickly. "But it's difficult to say how long this antibody will work. It is also difficult to say no such variant will come that can dodge the antibody developed through the previous variants and the vaccines."

A natural vaccine

Bijon Kumar Sil said there is vaccine inequality all over the world. "Many countries still couldn't provide their majority population with vaccines. But Omicron is going to remove this inequality naturally."

He said the antibody being developed among people through widespread infection is precious. "It's a very strong immunity against any variant that may come in the future. It'll work like vaccines and reduce the severity. It may not stop infection like the vaccines, but it'll protect people by reducing the severity of illness."

The experts also said though Omicron is a relatively weaker strain, it induces a powerful natural "herd immunity" similar to what a vaccine does.

He, however, said vaccination is still necessary to create a very strong resistance against Covid. "If people who have the natural antibodies are given vaccines, their immune system will be boosted to keep them protected from the virus for a longer period."

From pandemic to endemic

Bijon Kumar Sil said the massive Omicron infections are signaling the beginning of Covid's transition to become endemic.

"Omicron can hasten the transition from pandemic to endemic. It could end up being a seasonal variant. It means Covid won't go away completely in near future, but the virus will keep circulating in some parts of the world on a small scale," he said.

Dr Bijon said the Omicron wave will end across the world by September and Covid may be declared as endemic by some countries by next year if any unusual variant does not emerge that can dodge the existing antibodies.

He said most people, including babies, are also getting infected with Omicron. "But those who will be born after one or two months won't have antibodies as the virus transmission will slow down. If these babies are not vaccinated, they'll be vulnerable to the virus."

Dr Be-Nazir said, "We can say if any different variant doesn't emerge and the Omicron-induced antibodies work well, Covid will gradually weaken and become a seasonal virus."

He also said Covid will continue to transmit sporadically in different places of the world at a different time like Influenza. "So, we can say Omicron may be the beginning of the end of the Covid pandemic, but we still remain cautious about it."

Omicron may not be last variant

Dr Leanin, chairman of the medicine department at the Health and Hope Hospital, said public health experts are not giving focus on natural herd immunity. "Rather, they're talking about getting immunity through vaccination."

"Omicron may not be the last variant as the new variants will come with their own characteristics. We saw the antibody produced by the Delta variant couldn't resist Omicron infections. So, we can't say now that the immunity gained through the Omicron infections will protect us from new variants," he said.

Dr Lenin said the government should bring at least 80 percent of the population under the mass vaccination coverage to gain herd immunity and build up strong protection against Covid instead of depending on natural immunity.