Moderna, Pfizer update Covid-19 jabs to fight Omicron

Moderna and Pfizer Omicron sub-variants

Drug makers Moderna and Pfizer have this week announced that they have updated their Covid-19 vaccines to tackle the Omicron sub-variants responsible for new infections globally.

Photo credit: Apu Gomes | AFP

Drug makers Moderna and Pfizer have this week announced that they have updated their Covid-19 vaccines to tackle the Omicron sub-variants responsible for new infections globally.

Vaccine experts in the country say the move is timely, but we might not get the new doses soon.

The two pharmaceutical companies use a new form of technology called messenger RNA (mRNA) that can easily be tweaked to fight new Covid-19 variants.

This comes as researchers from the Kenya Medical Research Institute (Kemri) announced that the two Omicron sub-variants, BA.4 and BA.5, were responsible for the sixth wave in the country.

Many mutations

With the many mutations of the coronavirus, the United States Food and Drug Administration had asked vaccine manufacturers to update their vaccines to fight the current versions of the virus whose infections were rising at an alarming rate.

Scientists call the updated variant-specific jab a bivalent booster, which is the old vaccine with added protection for the newer lineages of the virus.

Announcing the results of their study in June, Moderna said the bivalent booster would offer more durable protection against variants of concern.

“We are submitting our preliminary data and analysis to regulators with the hope that the Omicron-containing bivalent booster will be available in the late summer,” they said.

However, the updated shots have not been approved for use by regulators at the global level.

Most prevalent

Vaccine expert Moses Mwangi explained to the Nation Wednesday that the BA.4 and BA.5 are the most prevalent currently.

“The virus seems to have drifted in a way that the current vaccines are not as effective as they were with the other strains,” he said.

At the moment, only the US has pre-purchased the vaccine, but Dr Mwangi says it should be available globally.

“The whole world needs it. But just like in the beginning, the circulation of the vaccine is likely to take a similar pattern. Good thing the current vaccines are still largely effective since they prevent severe disease and hospitalisations,” he said.