Vaccine makers like Moderna say they’re ‘standing ready’ for human bird flu pandemic

Major vaccine companies are preparing bird flu vaccines as the H5N1 virus that killed millions of animals mutates to infect humans.

Vaccine makers GSK, Moderna and CSL Seqirus have begun developing new human injections to tackle the rapidly spreading virus strain. Others, such as Sanofi, stock vaccines for the H5N1 virus that can serve as the basis for making injections tailored to the currently circulating strain.

Epidemiologists claim the risk to humans is low, but the specter of a new pandemic upending hundreds of millions of lives worldwide has kicked scientific research into high gear.

The strain currently rampaging through bird populations – H5N1 clade 2.3.4.4b – has not evolved to infect humans, but it has begun to spread among mammals at an unprecedented rate after causing record mortality among birds, raising the prospect that the stain gets dangerous mutations.

It has already leaked onto mammals such as minks, foxes, raccoons and bears, raising fears that it may soon acquire disturbing new mutations that could cause it to cause a human pandemic. The seals found in Maine are not shown on this map

Like all flu, the virus is primarily spread through airborne droplets that are inhaled or enter a person’s mouth, eyes, or nose

An 11-year-old Cambodian girl recently made headlines when she became the first person to die of bird flu this year.

But Cambodian scientists who sequenced the genomic makeup of the virus have confirmed that the clade that killed her – 2.3.2.1c – is not the one causing mass deaths of wild and domestic birds worldwide.

Still, the virus’s proven ability to rapidly mutate and jump from birds to mammals is beginning to worry experts. There are fewer than 1,000 human cases, but it has killed about 53 percent of people with the disease.

Director General of the World Health Organization, Tedros Ghebreyesus warned last month: ‘Since H5N1 first emerged in 1996 we have seen only rare and non-sustained transmission of H5N1 to and between humans, but we cannot assume this will continue and we must prepare for any change in status quo.’

The current bird flu outbreak has infected or killed more than 200 million birds and thousands of mammals worldwide, including minks in Spain, seals in the US, sea lions in South America and dolphins in the UK.

Executives at GSK, Moderna and CSL Seqirus told Reuters that they are developing or about to test human vaccines that better match the circulating subtype. Sanofi, meanwhile, said they are “ready” to begin production if necessary, with existing H5N1 vaccine strains in stock.

The US also has a stockpile of chickens to produce eggs critical to flu vaccine development, a method that has been used for some 80 years.

Hundreds of thousands of eggs are transferred to locked and guarded facilities every day, their locations not disclosed as a matter of national security.

Nasty make the vaccinea selected virus is injected into chicken eggs where it incubates for a few days and replicates in the same way as in a human.

Scientists harvest fluid in the egg that contains the virus and inactivate it so it can no longer cause disease, purifying it and leaving behind the crucial antigen that triggers an immune response in case of infection.

Meanwhile, Moderna, manufacturer of one of the two groundbreaking mRNA vaccines for Covid, is working on a pandemic flu vaccine tailored to avian flu using the same technology.

The basis of Moderna’s successful use of mRNA technology for Covid-19 was seasonal flu shots.

While vaccines typically take years, even a decade to develop, the Covid pandemic has kick-started the process, producing two highly effective mRNA vaccines in less than 12 months.

Raffael Nachbagauer, Executive Director of Moderna for Infectious Diseases, told Politico that the company will start clinical trials this year for an mRNA vaccine against pandemic avian flu.

If they do, he hopes they can “respond to a real pandemic outbreak within the space of two months” with a shot equipped to fight the specific circulating strain.

However, there is a concern that while many varieties of flu vaccines are pre-approved by regulatory agencies, reducing the risk of lengthy human clinical trials delaying the crucial distribution of injections, mass-producing versions tailored to the specific strain may take months. to last.

Raja Rajaram, head of global medical strategy at CSL Seqirus said, “Making the first dose is the easiest… The hardest part is mass production.”