Research in China has raised concerns that the world could be on the brink of another pandemic as bird flu cases surface across some regions in poultry, cattle, and humans, according to a report by the South China Morning Post (SCMP).
Avian influenza A viruses are divided into subtypes based on a combination of two proteins found on their surfaces – hemagglutinin and neuraminidase – referred to as HxNy.
Only two subtypes of avian influenza A – H1N1 and H3N2 – are known to circulate between humans, according to the Centres for Disease Control and Prevention (CDC) in the United States.
A study led by China’s top virologist, George Fu Gao, has published a paper with his team from the Chinese Academy of Sciences that investigated the particular strain of the H2N2 virus, according to SCMP.
Decades ago, another strain of H2N2 was responsible for the “Asian flu” pandemic, which broke out in 1957 in southern China and quickly spread around the world, claiming more than 1 million lives.
After the pandemic, H2N2 became a seasonal influenza, eventually disappearing from the human population by the end of the 1960s, though low pathogenicity strains continued to circulate in Chinese poultry.
In their paper published in the peer-reviewed journal Nature Communications, Gao and his research team said that after examining several strains of H2N2, one strain from 2021 could bind to both bird and human-type receptors on the surface of a host’s cells.
While this H2N2 strain still had a preference for bird receptors, the authors said the virus behind the Asian flu also started off with a dual preference, but adapted over time to become more inclined to human receptors.
The team’s experiments in mice, guinea pigs, and ferrets revealed that the H2N2 strain could rapidly adapt to mice and acquired mammalian-adapted mutations that helped it to transmit into guinea pigs and ferrets, the preferred animal model for influenza.
The researchers also examined the impact of single mutations on the transmission and virulence of the 2021 H2N2 strain, finding that some mutations could shift the binding preference to human receptors.
One of the most well-known variants of avian influenza A is H1N1, also known as swine flu, which caused the first influenza pandemic of the 21st century in 2009.
A new A(H5N1) strain exhibits higher level of air transmission
A common strain of the bird flu – H5N1 – has been making headlines due to outbreaks at US dairy farms, leading to more than 40 human infections in the US this year. Outbreaks in farm animals are worrisome because the virus can undergo reassortment, or the swapping of genome segments between viruses.
Strengthening avian influenza virus surveillance in animals and a public health risk assessment of novel influenza viruses are imperative for the control and prevention of emerging and re-emerging influenza pandemics and epidemics.
China reports highly-contagious and alcohol-resistant virus outbreak
Chinese media had reported a rise in norovirus infections among school students which has been spreading since October this year.
It was reported that a kindergarten in Xi’an, Shaanxi Province, reported at least 48 toddlers were infected around mid-October.
According to China’s National Centre for Disease Control and Prevention, the acute infectious disease caused by Norovirus has entered its peak period.
The organisation released a guideline to remind people about the contagious virus and highlighted that the Norovirus is highly resistant to common disinfectants, while also stating that alcohol is found to be ineffective against it.
It has a low infectious dose, a long detoxification time, a short immune protection time, and the entire population is generally susceptible – CDC (China).
The guide advises everyone to wash their hands properly with soap for at least 20 seconds before meals, after defecation, and before handling food which must be cooked thoroughly before consumption. Regular use of chlorine-based disinfectants on high-touch areas is also encouraged.
