appConfigEntityId

bodyType

customContents

entityId

entityUuid

isVideo

articlePageQuery

article

articleSchemaContent

content

hooksArticlePageAdvertisementConfigArticle

hooksArticlePageFloatingButtonConfigArticle

appConfig

filter

json

liveArticle

Victoria Bela

New evidence has emerged from research in China that the world could be on the brink of another pandemic as cases of bird flu surface across some regions in poultry, cattle and humans.
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 has raised concerns that a strain of the virus H2N2 recently found in the wild can now infect humans, raising the need for higher surveillance.
Many more strains of the virus have been found in birds and other animal populations around the world, some of which can infect humans.
George Fu Gao, an immunologist who served as director of the Chinese Centre for Disease Control and Prevention from 2017 to 2022, has published a paper with his team from the Chinese Academy of Sciences that investigated the particular strain of the H2N2 virus.
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, according to the CDC.
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 on November 19, 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, and found that some mutations could shift the binding preference to human receptors.
Despite similarities between the recent H2N2 strain and 1957 pandemic strains, the team said genetic differences and the length of time since the Asian flu meant the world lacked immunity against a future outbreak.
The team said the pathogenicity risk of H2N2 was still low, and there was still only limited transmission among mammals, reducing the overall risk of a pandemic from circulating H2N2 strains.
“However, the H2N2 [low pathogenicity avian influenza] strain just acquired limited mutations that enhance the virulence in mice and enable transmission between mammals,” the team said.
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 common strain of the bird flu – H5N1 – has been making headlines due to outbreaks on US dairy farms, leading to more than 40 human infections in the US this year, according to the CDC.
Most of the cases have been linked to exposure either to cows or poultry, and none of the recent cases have been due to human-to-human transmission, but the possibility still exists, experts say.
Of the more than 900 confirmed cases of H5N1 infection reported to the World Health Organization from 2003 to 2024, about half of the cases resulted in death.
Outbreaks in farm animals are worrisome because the virus can undergo reassortment, or the swapping of genome segments between viruses. Once an avian influenza virus enters pigs – which can carry both human and bird diseases – the risk of reassortment with human seasonal influenza increases.
Another paper published in Nature Microbiology on Monday by a team of researchers from the US and the Netherlands indicates H5N1 may present a much greater pandemic risk.
In a short article, the scientists said they set out to examine H5N1 due to the “abrupt change” seen in the virus recently, characterised by the ongoing outbreak in dairy cattle in the US.
The researchers examined viral shedding – the expulsion of viral particles through processes like exhalation – of the recent H5N1 strains compared to older strains within ferrets.
The team found that compared to H5N1 viruses from the 2000s, the recent viruses have a “low but increased” level of virus shedding into the air, which could explain the recent uptick in transmissions between cattle.
“Strengthening [avian influenza virus] surveillance in animals and a public health risk assessment of novel [avian influenza viruses] are imperative for the control and prevention of emerging and re-emerging influenza pandemics and epidemics,” the Chinese team said.


China tests first practical submarine solar power plant at 10-metre depth in the open sea

Rare earth exposure can triple low birthweight risk: Chinese study

China must enforce high standards of integrity for scientists

Is China’s fabled Empress Dowager Huayang buried near an airport? A study says yes

Science

How close is the next pandemic? Chinese researchers have some answers

A study led by China’s top virologist has raised concerns that a strain of the virus H2N2 recently found in the wild now has the ability to infect humans. Photo: Reuters 

Beyond the China coronavirus: the deadly diseases Hong Kong and Asia have beaten before

Medical staff at the Jinyintan hospital in Wuhan, China, where patients with pneumonia caused by the new strain of coronavirus are being treated. Photo: Reuters

Flat copy of a series of photographs from exhibition "A Chronicle of Pasteurian Research in Hong Kong" which illustrates the plague to new emerging diseases happened in Hong Kong's Tai Ping Shan Area in 1890s. Pictured at University Museum and Art Gallery in The University of Hong Kong. 20MAY08

The President of the Legislative Council (LegCo), Mr Andrew Leung (first left), today (November 21) receives seasonal influenza vaccination at the LegCo Complex. Looking on is the Secretary for Food and Health, Professor Sophia Chan (second left). Photo: ISD

FILE - In this May 21, 2015, file photo, a thermal camera monitor shows the body temperature of passengers arriving from overseas against possible MERS, Middle East Respiratory Syndrome, virus at the Incheon International Airport in Incheon, South Korea. South Korea on Wednesday, Jan. 8, 2020, has put a 36-year-old Chinese woman under isolated treatment amid concerns that she brought back a form of viral pneumonia that has sickened dozens in mainland China and Hong Kong in recent weeks. (Kim Ju-sung/Yonhap via AP, File)

epa08006079 Indian Bruhat Bangalore Mahanagara Palike (BBMP) civic administration worker uses a fogging machine during a fumigation operation to eradicate the mosquito menace at Cubbon Park, in Bangalore, India, 18 November 2019. Mosquitos carrying deadly diseases including Malaria, Dengue fever and the West Nile virus often spread across the country. EPA-EFE/JAGADEESH NV

FILE - In this Sept. 29, 2016 file photo, Aedes aegypti mosquitoes, responsible for transmitting Zika, sit in a petri dish at the Fiocruz Institute in Recife, Brazil. The South American country declared an end to its public health emergency for the Zika virus on Thursday, May 11, 2017, 18 months after a surge in cases drew headlines around the world. (AP Photo/Felipe Dana, File)

A health worker administers free polio vaccine to a child during a government-led mass vaccination program in Quezon City, Metro Manila, Philippines, October 14, 2019. REUTERS/Eloisa Lopez

Recruits of the paramilitary police receive injections of the H1N1 vaccine at a military base in Taiyuan, Shanxi province February 2, 2010. REUTERS/Stringer (CHINA - Tags: HEALTH MILITARY) CHINA OUT. NO COMMERCIAL OR EDITORIAL SALES IN CHINA

How Hong Kong flu struck without warning 50 years ago, and claimed over a million lives worldwide

Scores of patients crowd the waiting hall of a clinic on Hong Kong Island during the influenza epidemic in July 1968. Photo: SCMP

Nurses wheel a "patient" to an isolation ward during a SARS drill at Princess Margaret Hospital. 30 OCTOBER 2003

SCMP clipping from May 1 1969

scmp

A Government doctor and nurse cope with a steady stream of patients during the influenza epidemic in Hong Kong. 27JUL68

SCMP ads from July 31 1968

Why sick minks are reigniting worries about bird flu spreading to humans

sick minks are reigniting worries about bird flu spreading to humans. Photo: AP/File

Heavy machinery is cleansed after being used by members of Danish health authorities, assisted by members of the Danish Armed Forces in disposing of dead mink in a military area near Holstebro, Denmark, on November 9 2020. Photo: AP/File

Chinese-funded Africa CDC laboratory opens in Ethiopia as Beijing looks to health diplomacy to boost influence

Chinese and African delegates tour the Africa CDC research lab following its official opening on Friday. Photo: Xinhua

The lab is named after the pioneering Chinese-Malaysian doctor Wu Lien-Teh, pictured in a laboratory in Harbin in 1911. Photo: Courtesy of the family of Wu Yu-lin

The research lab in Addis Ababa was officially opened last week. Photo: Xinhua

News

China

China’s top infectious disease expert says a strain of avian influenza virus is adapting and could make the leap from birds to mammals


China’s top infectious disease expert says a strain of avian influenza virus is adapting and could make the leap from birds to mammals.


How close is the next pandemic? Chinese researchers have some answers

.css-1c6uqr6{color:inherit;font-weight:inherit;font-size:inherit;font-family:inherit;line-height:inherit;overflow-wrap:break-word;}China’s top infectious disease expert says a strain of avian influenza virus is adapting and could make the leap from birds to mammals

China’s top infectious disease expert says a strain of avian influenza virus is adapting and could make the leap from birds to mammals