EVEN AS Maharashtra continues to log the highest number of Omicron cases in the country, 22 of the 30 patients infected with the variant admitted at the BMC-run Seven Hills hospital till Wednesday were fully vaccinated.
“Till Wednesday, we had 30 Omicron patients. Twenty two of those were fully vaccinated while the remaining eight were partially immunised,” said Dr Balkrishna Adsul, the dean of Seven Hills Hospital which is the primary designated hospital to treat Omicron patients from Mumbai. Most of these patients are asymptomatic or mildly symptomatic. Over half of these live outside Mumbai.
This again highlights the fact that Omicron, with 37 mutations in its spike protein, can evade vaccines leading to more reinfections and breakthrough infections, where a patient contracts Covid-19 despite being fully vaccinated against SARS-Cov-2.
“This is because the strain is significantly different from the earlier strains against which the current vaccines were designed. Although vaccination and prior infection still seem to offer some protection against severe disease, they do not appear to protect significantly against infection. Protection against severe disease [in case of Omicron infection] does appear to be lower than that against the earlier strains,” said Dr Lancelot Pinto, pulmonologist and epidemiologist from Hinduja Hospital.
A similar trend has also been observed across the country. Data shared by Union Health Secretary Rajesh Bhushan on Friday showed that 91% of Omicron infected cases in India were fully vaccinated, with some having been given booster shots.
Citing an example, Dr Sujit Chatterjee, CEO of L H Hiranandani Hospital, Powai, said as the influenza virus undergoes mutations regularly, its vaccine is being redeveloped each year accordingly. Similarly, the current anti-Covid vaccines won’t be effective as they won’t be specific to the new strain—Omicron.
“It can be exactly like a new disease. It depends on the virulence of the virus. Thus, there may be a great spread of the disease if people don’t follow Covid-appropriate behaviour,” he said.
Amid rising cases of breakthrough infections, some doctors highlighted the need for booster shots which can provide additional protection against the new variant.
“Booster dose is a necessity for the frontline workers and senior citizens. Initial results of studies conducted show that people who get a booster shot, or third dose of vaccine, may be better protected. Though these data are preliminary, they suggest that getting a booster may add more immunity,” said Dr Chatterjee.
However, Tedros Adhanom Ghebreyesus, director general of World Health Organisation (WHO), on December 22 cautioned against blanket use of booster doses. “No country can boost its way out of the pandemic and boosters cannot be seen as a ticket to go ahead with planned celebrations without the need for other precautions,” he said in a statement.
Till December 24 evening, India recorded 358 Omicron cases in 17 states, out of which the highest, 108, are in Maharashtra.