Major vaccine companies are preparing vaccines against bird flu if the H5N1 virus that has killed millions of animals mutates to infect humans.
Vaccine makers GSK, Moderna and CSL Seqirus have begun developing new human vaccines to attack the fast-spreading strain of the virus. Others, like Sanofi, have vaccines for the H5N1 virus in stock that could serve as the basis for producing injections tailored to the currently circulating strain.
Epidemiologists say the risk to humans is low, but the specter of another pandemic claiming hundreds of millions of lives around the world has accelerated scientific investigation.
The strain currently rampaging through bird populations, H5N1 clade 2.3.4.4b, has not evolved to infect humans, but has begun to spread at an unprecedented rate in mammals after causing record deaths in birds. , increasing the chance that the blot will acquire dangerous mutations.
Tens of thousands of birds die suddenly on the Peruvian coast and throughout the American continent. Municipal workers collect dead pelicans on the Santa María beach in Lima, Peru (Photo dated November 30, 2022)
It has already spread to mammals such as mink, foxes, raccoons and bears, raising fears that it will soon acquire worrying new mutations that could cause a human pandemic. Seals found in Maine are not reflected on this map.
Like all flus, the virus is transmitted primarily through airborne droplets that are inhaled or enter a person’s mouth, eyes, or nose.
An 11-year-old Cambodian girl made headlines recently when she became the first human to die of bird flu this year.
But Cambodian scientists who sequenced the genomic makeup of the virus confirmed that the clade that killed it, 2.3.2.1c, is not the one that causes mass deaths in wild and domestic birds globally.
Still, the virus’s proven ability to rapidly mutate and jump from birds to mammals has begun to worry experts. There have been fewer than 1,000 cases in people, but it has killed about 53 percent of people diagnosed with the disease.
Tedros Ghebreyesus, Director General of the World Health Organization warned last month: ‘Since H5N1 first appeared 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 must prepare for any change in the status quo. ‘
The current outbreak of bird flu has infected or killed more than 200 million birds worldwide and thousands of mammals, including mink in Spain, seals in the US, sea lions in South America and dolphins in the UK.
GSK, Moderna and CSL Seqirus executives told Reuters who are developing or about to test human vaccine samples that best match the circulating subtype. Meanwhile, Sanofi said they “stand ready” to start production if necessary, with the existing H5N1 vaccine strains in stock.
The United States also has a stockpile of chickens to produce eggs that are crucial for the development of flu vaccines, a method that has been used for about 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.
TO make the vaccinea selected virus is injected into chicken eggs where it incubates and replicates for a few days in the same way as it would in a human.
Scientists collect fluid inside the egg that contains the virus and inactivate it so it can no longer cause disease, purify it, and leave behind the crucial antigen that elicits an immune response in case of infection.
Meanwhile, Moderna, maker of one of the two historical mRNA vaccines for Covid, is working on a pandemic flu vaccine adapted to bird flu using the same technology.
The foundation of the successful harnessing of Moderna’s mRNA technology for Covid-19 was in seasonal flu vaccines.
While vaccines would normally take years, even a decade, to develop, the covid pandemic sped up the process, producing two highly effective mRNA vaccines in less than 12 months.
Raffael Nachbagauer, CEO of infectious diseases at Moderna, told politician that the company is initiating clinical studies for an mRNA vaccine against pandemic avian influenza this year.
When they do, he hopes they can respond “within a two-month period to a true pandemic outbreak” with an injection equipped to combat the specific circulating strain.
However, there are concerns that while many varieties of flu vaccines have been previously approved by regulators, mitigating the risk of lengthy human clinical trials slowing the crucial distribution of shots, mass-produced versions that have been modified according to specific needs the tension could take months.
Raja Rajaram, head of global medical strategy at CSL Seqirus, said: “Creating the first dose is the easiest… Manufacturing in large quantities is the hardest.”
