Category: Flu Virus

After declining trends over the past few weeks, flu activity rose in some parts of the country, while COVID-19 and respiratory syncytial virus (RSV) levels continued overall declines, according to the latest updates today from the US Centers for Disease Control and Prevention (CDC).

Though flu indicators declined following the winter holidays, the CDC has said that it is watching for a second peak that sometimes occurs after the winter holidays. In its respiratory virus snapshot, the CDC said some regions are seeing rising flu indicators, especially in the Midwest and South-Central regions.

Also, the percentage of respiratory samples that were positive for flu at clinical labs rose last week to 16.2%, compared to 14.2% the previous week, the CDC said in its weekly flu update. Influenza A is still dominant, with 60.4% of subtyped samples belonging to the 2009 H1N1 subtype. There were increases in the percentages of H3N2 and influenza B detections compared to the previous week.

Outpatient visits for flulike illness held steady and have been above the national baseline since November. However, CDC surveillance shows a rise for one age-group: people ages 5 to 24 years.

Eight more pediatric flu deaths were reported, lifting the season's total to 65. The deaths all occurred in January. Four were linked to influenza A, and four involved influenza B. Overall deaths from flu declined slightly compared to the week before.

Most COVID markers declined last week, except for deaths, which held steady. Hospitalizations for COVID, one of the CDC's main severity indicators, decreased by 10.9% compared to the previous week.

Among early indicators, test positivity declined 4.6% and it at 6.3% nationally. However, levels were a bit higher in the Midwest, South, and parts of the Northeast. Emergency department visits dropped 11% compared to the previous week and remain highest for infants and seniors.

The CDC's wastewater tracking shows that virus detection levels are high, down from "very high" the week before. Meanwhile, Biobot wastewater tracking shows that a steady decline in SARS-CoV-2 detections since late December has slowed, with the western region showing a slight increase.

In its every-other-week variant projections, the CDC said JN.1 continued to expand its dominance and now makes up 93.1% of sequenced samples, up from 84.3% in its last update.

Earlier this week, South African virus sequencing experts identified a new lineage from samples in South Africa that has more than 100 mutations. Tulio de Oliveira, PhD, who directs South Africa's Centre for Epidemic Response and Innovation and is also deputy director of the Wellcome Sanger Institute Genomic Surveillance Unit, said on X (formerly Twitter) that the lineage is the most divergent one identified this year.

The same group in South Africa was the first to identify the Omicron SARS-CoV-2 variant.

Scientists have designated the new variant as BA.2.87.

The lineage has been found in eight samples from two different provinces between September and November. It is distinct from currently circulating Omicron lineages and shows some diversity in the samples collected over a 10-week period.

De Oliveira said enhanced genetic surveillance shows very few signs that the new variant is spreading widely or replacing current lineages. He added that work is under way to assess potential transmissibility and pathogenicity.

The CDC said RSV activity has declined across many parts of the nation. Hospitalizations, still elevated, are declining in young children, but they remain elevated in older adults.

In its vaccination updates, the CDC estimated that 20.8% of eligible adults ages 60 and older have received an RSV vaccine.

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US flu markers show hint of a second wind - University of Minnesota Twin Cities

A deadly type of bird flu has been found in gentoo penguins for the first time, sparkingfears the virus could spread among Antarctica's remaining colonies.

Researchers from the Scientific Committee on Antarctic Research (SCAR) found about 35 penguins dead in the Falkland Islands in the South Atlantic on 19 January.

Samples taken from two of the dead penguins came back positive for the H5N1 avian influenza virus, said Ralph Vanstreels, a veterinarian who works with SCAR.

The Falkland Islands government said that many more gentoos were dying under similar circumstances.

As of 30 January, 'there are over 200 chicks dead alongside a handful of adults', said government spokesperson Sally Heathman.

The deaths confirm that gentoo penguins are susceptible to the lethal disease that has decimated bird populations across the world in recent months.

However, gentoos rarely travel between the Falklands off Argentina's coast and the Antarctic Peninsula, which lies some 800 miles (1,300 kilometres) to the south.

That means traveling penguins are unlikely to drive the spread to the southern continent, said Vanstreels, a researcher affiliated with University of California-Davis.

'The role that gentoo penguins could have, instead, is to serve as local reservoirs of infection,' he said.

'That is, maintain a pool of susceptible hosts that never leaves the islands.'

Bird flu is an infectious disease caused by a variant of the influenza A virus.

It is unique in that it can be transmitted directly from birds to humans.

There are 15 different strains of the virus, with the H5N1 strain known to affect humans.

Humans can catch bird flu through close contact with live infected birds.

Heathman said the Falkland Islands government was also awaiting test results from rockhopper penguins and 'preparing for a large-scale outbreak.'

In nearby South Georgia, authorities ruled out a report of bird flu suspected in king penguins after a detailed survey of the site, said Meagan Dewar, who leads SCAR's Antarctic Wildlife Health Network.

Hundreds of thousands of penguins gather in tightly packed colonies on the Antarctic continent and nearby islands, which could enable the deadly virus to easily jump between individuals.

Conservationists are more concerned about other species, Vanstreels said.

Elephant seals and fur seals have died in larger numbers from bird flu in South Georgia, following mass casualties in those species in South America.

'This is especially concerning because South Georgia is home to 95 percent of the world's population of Antarctic fur seals,' he said.

'If that population collapses, the species will be in a critical situation.'

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Bird flu is found in PENGUINS for the first time - sparking fears the deadly virus could spread among Antarcti - Daily Mail

Chinese health officials today announce that a 63-year-old woman from Anhui province who died in late November was coinfected with H3N2 seasonal flu and a H10N5 flu virus that is genetically related to avian subtypes.

The country's National Administration for Disease Control and Prevention posted the details on its website, which were translated and posted by FluTrackers, an infectious disease news message board. The woman's symptoms began on November 30, including cough, fever, and sore throat. Officials said she had underlying health conditions.

A few days later, she was hospitalized after her condition worsened. On December 7, the patient was transferred to a hospital in Zhejiang province, where she died on December 16.

During routine surveillance on samples from fatal cases, lab scientists in Zhejiang province isolated H3N2 seasonal flu, along with the H10N5 subtype. Repeat testing at the China Centers for Disease Control and Prevention confirmed the findings.

Investigations involving the close contacts that the woman had in the two provinces found no suspicious cases, and nucleic acid tests were negative for people who were screened.

Scientists also conducted complete sequencing of the H10N5 virus and found that it was completely of poultry origin and doesn't have the capacity to easily infect humans. Officials said the woman's illness is an example of cross-species transmission from poultry to humans. The report did not say how the woman may have contracted the H10N5 virus.

Officials said the overall health risk is low and there is no sign of human-to-human transmission.

Hong Kong's Centre for Health Protection said today that it is monitoring developments with the case. "All novel influenza A infections, including H10N5, are notifiable infectious diseases in Hong Kong," it added.

China has reported a few human H10 cases before. For example, in 2013 officials reported a fatal case involving a H10N8 virus that carried genes from H9N2 avian flu, which circulates in Chinese poultry and occasionally infects humans. H10 has also been detected in Australian slaughterhouse workers and in Egyptian infants.

In 2021, China reported an H10N3 avian flu case in a man from Jiangsu province, the first known case involving the strain. He had no clear exposure to poultry, and the virus hadn't recently been detected in local poultry.

The woman's H10N5 infection appears to be the first known case in a human. Background information on influenza A virus subtypes from the US Centers for Disease Control and Prevention said most H10 infections in people have involved exposure to infected poultry.

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China reports woman's death from H3N2-H10N5 flu coinfection - University of Minnesota Twin Cities

Bird flu viruses may pack a little taste of home to help them adapt to life in new hosts.

Viruses usually infect only certain types of hosts. For instance, many viruses that infect humans dont infect other animals. But influenza viruses often seem to jump from birds to other species. In 2009, the H1N1 swine flu made the leap from birds to pigs and then into people, setting off a pandemic (SN: 12/18/09). Even now, an outbreak of avian influenza is infecting and killing birds, sea mammals and some other animals around the world (SN: 1/25/24). No one knows whether that flu virus may eventually infect people and, if it does, whether it will have the ability to spread easily and cause a pandemic.

Despite plenty of instances of bird flu viruses infecting people, scientists werent sure exactly how the viruses overtake other species cells. A new study offers a clue about one of the first steps avian influenza viruses use to adapt to infect humans and other animals.

Avian influenza viruses tuck proteins that aid replication into their viral particles, researchers at the Chinese Academy of Agricultural Sciences in Harbin and colleagues have discovered. The reproductive aids, called ANP32 proteins, may help flu viruses make the jump from birds to mammals, the researchers report January 31 in Science Advances.

The finding may help researchers better understand and predict which flu viruses have the potential to cause a pandemic.

When viruses infect a host, they dont carry everything with them that they need, and they just hijack things that are already inside the cell to help them replicate, says Wendy Barclay, a molecular virologist at Imperial College London. Researchers knew that the viruses come equipped with basic replication machinery called polymerases. But that may not be enough to really establish an infection.

The viruses need to hijack host proteins to help the invaders quickly make copies of themselves. That includes ANP32 proteins, which help bring together proteins that form the polymerase copy machines.

Todays flu virus needs this help in order to replicate itself fast enough inside any host cell so that it doesnt get clobbered by our immune response and shut down, says Barclay, who was not involved in the work.

The researchers examined avian influenza proteins inside mammalian cells under electron microscopes and found that some viral particles carried a little bit of bird ANP32 with them. The protein is probably attached to the viral polymerase and gets bundled into the viral particle along with the rest of the replication machinery, the researchers discovered. The stronger the attraction between the polymerase and ANP32 proteins, the more helper protein that gets incorporated into viruses.

It has been a mystery how avian influenza viruses, which have different ANP32 proteins than mammals do, could grab onto and use the ANP32 proteins in human and and other mammalian cells. Researchers thought that perhaps some flu viruses already had mutations that would allow viral polymerases to interact with mammalian ANP32 proteins.

But the new study suggests that by packing their own bird versions of the proteins, flu viruses dont immediately need to grab host ANP32 proteins. Instead, the virus can use the avian ANP32 protein for one round of copies inside the human or other animal cell. This initial foothold maybe allows the virus to just replicate enough to make a few mutations, Barclay says.

Some of those mutations may then allow the bird version of the polymerase to interact with mammalian ANP32 proteins. Viruses that carried the bird version of ANP32 were more likely to acquire such adaptive mutations when grown in human cells or in mice, the researchers found. This explains how avian viruses, which shouldnt be able to replicate in human cells, are in fact able to replicate and evolve to interact with human ANP32, says Jacob Yount, a viral immunologist at the Ohio State University College of Medicine in Columbus who was not involved in the research.

If the findings hold up to further investigation, scientists may be able predict which viruses are more likely to cause a pandemic by looking at the strength of interaction between the viral polymerase and ANP32, Barclay says. There may be some [bird flu viruses] that are much better at pulling the ANP from the chicken or the duck into the human cell than others, she says. Those may be the ones which come in and get the foothold and get going with their evolution process more easily than ones [that] perhaps have a weaker interaction.

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Bird flu viruses may pack tools that help them infect human cells - Science News Magazine

Influenza A(H1N1), also known as swine flu, influenza B, and Covid have been found responsible for the viral fever outbreak in several villages of Soru Rural Municipality in Mugu district.

According to Charitra Dhami, health coordinator of the rural municipality, the National Public Health Laboratory, which had carried out tests on swab samples collected from the affected villages, confirmed the infection of A(H1N1), influenza B and Covid in the infected people.

Laboratory tests show spread of multiple virusesA(H1N1), influenza B and Covid-19in the disease-hit areas, Dhami told the Post over the phone from Mugu. The Ministry of Health and Population has deployed an expert team following the confirmation of multiple potentially deadly viruses in our area.

At least three people have died and over 200 have been infected by what was being called a mystery disease that broke out last week in Jima, Bhiee, Natharpu Sipa, Khyalcha, Bumcha, Purumuru, Mera, and Kalai villages of the rural municipality. The deceased include a 75-year-old male and 72- and 24-year-old females.

Health workers deployed in the affected villages said infected persons complained of headaches, muscle aches, loss of appetite, fatigue and sweating.

The Health Office, Mugu deployed a team of health workers and doctors to the affected rural municipalities. They collected swab samples of infected persons and sent them to the National Public Health Laboratory.

We deployed another team to the disease-hit areas of Mugu today, said Dr Prakash Budhathoki, spokesman for the health ministry. The team will reach the affected villages on Wednesday and start its work.

Research suggests the spread of multiple viruses in the same place at the same time is a serious thing, as you could get infected by more than one virus, which increases the chances of the patients mortality.

According to the World Health Organisations Global Influenza Surveillance, 17 cases of H1N1 infection have been reported in Nepal since January this year. Similarly, four cases of influenza B have been confirmed in the same period.

Both H1N1 and influenza B and Covid viruses are highly contagious and spread from person to person through airborne droplets of infected persons.

Doctors advise one and all to avoid crowds, wear face masks that protect not only from infection from various viruses but also polluted air, to wash hands frequently and maintain social distance.

Of late, major hospitals in the country have reported a surge in new cases of respiratory illnesses. Doctors say most of the virusesadenovirus, rhinovirus, and seasonal influenzabecome active in the winter season.

They say that most symptoms of the H1N1, influenza B coronavirus overlap, which can cause confusion and lead to misdiagnosis. In both infections (coronavirus and influenza), patients suffer from fever, cough, shortness of breath, fatigue, sore throat, runny or stuffy nose, headache, vomiting and diarrhoea, among other symptoms.

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'Mystery disease' that killed 3 in Mugu may be flu-Covid combo - The Kathmandu Post

MADISON, Wis. Air sampling can accurately detect flu and COVID-19 levels, according to a new study from the University of Wisconsin-Madison School of Medicine and Public Health.

The study involved placing air samplers in the Oregon School Districts school cafeterias to collect virus particles. Testing took place during the 2022-23 school year. Researchers found air sampling can be an accurate way to measure an outbreak.

As widespread community testing for the coronavirus wanes, it appears that air sampling can provide a good awareness of the presence of both the influenza A virus and the SARS-CoV-2 virus that causes COVID-19, said Dr. Jonathan Temte, lead author of the study and professor of family medicine and community health at UW. Schools are excellent places to test these methods because of their role in spreading respiratory viruses.

The study, published in JAMA Network Open, is part of a long-term respiratory surveillance project which started in 2013. Its called Oregon Child Absenteeism due to Respiratory Disease Study, or ORCHARDS. In the study, seven Oregon School District school buildings were given air monitors, which trap the virus particles in filters.

This way of measuring the virus was compared to three other methods of testing, including rapid antigen testing at school, daily counts of absent students because of suspected respiratory viruses and at-home specimen collection by students.

Similar respiratory disease patterns were found in all four methods of testings.

All the methods demonstrated the epidemic nature of influenza and the constancy of SARS-CoV-2 over the assessment period, Temte said.

Results show an influenza A outbreak in the district that had peaked from Dec. 11-24, 2022. That dropped off following the winter break.

For COVID-19, low-to-moderate levels of the virus persisted in at least two buildings from the beginning of the school year until the end of Jan. 2023. However, there was a difference between methods. The antigen testing didnt pick up on any COVID-19 following winter break, whereas the other methods did.

Researchers said the results of the study are beneficial because this method of collecting data on disease outbreaks is non-invasive and is anonymous.

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Study shows flu, COVID-19 levels can be detected through air samples - Spectrum News 1

A new study reports that multiple seasons of being vaccinated with non-egg-based flu vaccines may help refocus peoples vaccine-induced immune responses to better target circulating influenza viruses.

For more than 70 years, most influenza (flu) vaccines have been produced by growing influenza viruses in chicken eggs. One drawback of this production method is that it often introduces changes to the viruses as they adapt to grow in eggs. These so-called egg-adapted changes can render the vaccine viruses significantly different from circulating wild flu viruses. As a result, egg-based vaccines can prompt a persons immune system to direct antibodies at targets, or epitopes, on the vaccine viruses that are not found on circulating viruses. This could result in reduced vaccine effectiveness (VE). Research has shown this antibody response could be reinforced by repeated egg-based vaccination, which could contribute to further reductions in VE over time.

Two non-egg-based flu vaccinesthe recombinant flu vaccine and the cell culture-based flu vaccinewere introduced in the United States during the 2013-14 flu season. The study, which looked at data from a randomized clinical trial conducted during the 2018-2019 and 2019-2021 influenza seasons, compared antibody responses following vaccination with recombinant, cell culture-based, or standard egg-based influenza vaccines among 1,400 people.

The results indicate that vaccination with recombinant influenza vaccine induced the most robust antibody responses against multiple vaccine viruses. They also indicate that repeated vaccination with non-egg-based flu vaccines could overcome the effect of prior repeated vaccination with egg-based vaccines. Redirecting the antibody responses away from egg-adapted epitopes resulted in higher antibody responses to cell-grown viruses that better represent circulating viruses.

The findings could inform decision-making related to optimal vaccination strategies for people in different age groups and populations.

For one, vaccination with non-egg-based flu vaccines could be especially beneficial for people who have been repeatedly vaccinated with egg-based vaccines. This could include health care personnel who have annual vaccination requirements and older adults, who tend to have been vaccinated more frequently than other groups of people. The study also adds to the evidence that when young children are first immunized against influenza, they may benefit from getting a non-egg-based vaccine, as a persons first exposure to influenza virus can play a role in shaping their immune response to subsequent influenza virus infection or flu vaccinations.

Currently, recombinant and cell-based flu vaccines are the only flu vaccines made without the use of eggs that are licensed for use in the United States. The flu viruses used in the cell-based vaccines are grown in cultured cells of mammalian origin. Recombinant flu vaccines do not require the use of a candidate vaccine virus (CVV) for production because they are created synthetically.

Some observational studies have shown greater protection against flu among people who received cell-based inactivated influenza vaccines compared with those who received standard-dose egg-based vaccines. Nevertheless, egg-based vaccines remain the most widely available flu vaccines and are an important preventive tool. The benefits of vaccination with any flu vaccine, including egg-based flu vaccine, still far outweigh the potential risks of not getting vaccinated. Currently CDC does not have a preference for the use of any one flu vaccine over another except among people 65 years and older. When available, CDC recommends people 65 years and older get a high-dose, an adjuvanted, or a recombinant flu vaccinebecause a review of existing studies suggested that, in this age group, these vaccines are potentially more effective than standard-dose unadjuvanted flu vaccines.

Redirecting antibody responses from egg-adapted epitopes following repeat vaccination with recombinant or cell culture-based versus egg-based influenza vaccines. Nature Communications, 4 January 2024.

READ ALSO:

Recombinant or Standard-Dose Influenza Vaccine in Adults under 65 Years of Age

In this cluster-randomized observational study, Kaiser Permanente Northern California facilities routinely administered either a high-dose recombinant influenza vaccine (Flublok Quadrivalent) or one of two standard-dose influenza vaccines during the 20182019 and 20192020 influenza seasons to adults 50 to 64 years of age (primary age group) and 18 to 49 years of age. he high-dose recombinant vaccine conferred more protection against PCR-confirmed influenza than an egg-based standard-dose vaccine among adults between the ages of 50 and 64 years. NEJM

Leveraging Modernization of the US Influenza Vaccine Manufacturing Base to Make Better Vaccines: A Work in Progress

Initial efforts to build up domestic vaccine manufacturing started in 2004. HHS funded contracts to bolster supplies of embryonated eggs so they were available year-round and to develop a cell-based influenza vaccine with a provision to build a domestic facility for vaccine production. BARDA followed these contracts with additional cell-based influenza vaccine, adjuvant, recombinant influenza vaccine, and influenza vaccine production facility contracts. In parallel, the DoD funded the development of alternate platforms for influenza vaccine production. These efforts have resulted in the licensure of new cell-based, recombinant, and adjuvanted or dose-sparing influenza vaccines. While the use of non-egg-based vaccines is growing, the field effectiveness data in the years since their licensure suggest that we are still being served by mediocre vaccines. Vaccine Insights

Development of Cross-Reactive Live Attenuated Influenza Vaccine Candidates against Both Lineages of Influenza B Virus

The urgent need for broadly protective influenza B virus vaccines is underscored by the significant burden in the human population and the relatively high mutation rate of these viruses. A reverse genetics (RG) system is required to rapidly update the antigenic composition of vaccines, as well as to design LAIVs with a broader spectrum of protection. Such a system has been developed for the Russian LAIVs only for type A strains, but not for influenza B viruses (IBV). Vaccines

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Study Shows Potential Benefits of Newer, Non-Egg-Based Flu Vaccines - Global Biodefense

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Chinese authorities announced the death of a 63 year old woman due to a coinfection of two different types of flu. The woman from the Anhui province was infected with H3N2 seasonal flu and a H10N5 flu virus that is genetically related to avian subtypes. " According to the official website of the National Administration of Disease Control and Prevention, the National Administration of Disease Control and Prevention reported that a case of H3N2 and H10N5 mixed infection was discovered in Zhejiang Province," FluTrackers an infectious disease news message board has translated the message posted by the China authorities.

As per the report, the symptoms the woman had included cough, fever, and sore throat. Her symptoms began on November 30. She was hospitalised a few days later as her health condition worsened. A week later, on December 7 she was transferred to a hospital in Zhejiang province. She died on December 16.

H3N2, a subtype of the influenza A virus, is known for its potential to cause severe flu seasons. Characterized by frequent mutations, H3N2 can quickly evolve, posing challenges for vaccine effectiveness. It is associated with more severe symptoms, higher hospitalization rates, and increased mortality, particularly impacting the elderly and young children. The virus exhibits a propensity for antigenic drift, leading to variations that evade immunity from previous exposures or vaccinations. Its rapid transmission in crowded settings contributes to widespread outbreaks. Vigilance and timely vaccination campaigns are crucial in mitigating the impact of H3N2, as it continues to pose a significant public health threat.

H10 viruses are primarily found in wild birds, and there have been cases of H10N5 infection reported in humans. However, the overall prevalence and impact on human health have been relatively low compared to other influenza subtypes. Continuous monitoring of avian influenza strains, including H10N5, is essential to assess any potential threats to public health. For the latest and most accurate information on H10N5 or any other influenza strains, it is recommended to refer to recent updates from health authorities and research institutions.

Experts assessed that the complete genetic analysis of the virus showed that the H10N5 virus was of poultry origin and did not have the ability to effectively infect humans. The epidemic was an occasional cross-species transmission from poultry to humans. The risk of the virus infecting humans is low and no human-to-human transmission has occurred.

Experts suggest that the public should avoid contact with sick and dead poultry in daily life and try to avoid direct contact with live poultry; pay attention to dietary hygiene and improve self-protection awareness. If you have fever and respiratory symptoms, you should wear a mask and seek medical treatment as soon as possible.

Fingernails can be home to 32 different types of bacteria; here's how to keep them clean

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Woman dies of flu co-infection in China: Know what this means - IndiaTimes

Researchers have discovered a new class of antibodies capable of neutralizing various flu virus strains, potentially aiding in the development of more broadly protective flu vaccines. This breakthrough, to be published in PLOS Biology, emphasizes the importance of diversifying flu vaccine production methods and provides new avenues for vaccine design.

Researchers led by Holly Simmons from the University of Pittsburgh School of Medicine have discovered a new class of antibodies that show potential in neutralizing various types of influenza viruses. This significant advancement, which might aid in the creation of more universally effective flu vaccines, was recently published in the journal PLOS Biology.

A flu vaccine prompts the immune system to make antibodies that can bind to a viral protein called hemagglutinin on the outside of an invading flu virus, blocking it from entering a persons cells. Different antibodies bind to different parts of hemagglutinin in different ways, and hemagglutinin itself evolves over time, resulting in the emergence of new flu strains that can evade old antibodies. New flu vaccines are offered each year based on predictions of whatever the most dominant strains will be.

Extensive research efforts are paving the way to development of flu vaccines that are better at protecting against multiple strains at once. Many scientists are focused on antibodies that can simultaneously protect against flu subtypes known as H1 and H3, which come in multiple strains and are responsible for widespread infection.

Humans mount convergent H1N1-H3N2 neutralizing antibody responses to influenza virus. Panels are derived from structures reported by Simmons et al., (PDB 7TRH, 7RRI and 3UBE by Xu et al., for the model of receptor engagement). Credit: Kevin McCarthy (CC-BY 4.0)

Simmons and colleagues homed in on a particular challenge in this endeavora small change found in some H1 strains in the sequence of building blocks that makes up hemagglutinin. Certain antibodies capable of neutralizing H3 can also neutralize H1, but not if its hemagglutinin has this change, known as the 133a insertion.

Now, in a series of experiments conducted with blood samples from patients, the researchers have identified a novel class of antibodies capable of neutralizing both certain H3 strains and certain H1 strains with or without the 133a insertion. Distinct molecular characteristics set these antibodies apart from other antibodies capable of cross-neutralizing H1 and H3 strains via other means.

This research expands the list of antibodies that could potentially contribute to development of a flu virus that achieves broader protection through an assortment of molecular mechanisms. It also adds to growing evidence supporting a move away from flu vaccines grown in chicken eggscurrently the most common manufacturing approach.

The authors add, We need annual influenza virus vaccines to keep pace with continuing viral evolution. Our work suggests that the barriers to eliciting more broadly protective immunity may be surprisingly low. Given the right series of influenza virus exposures/vaccinations, it is possible to for humans to mount robust antibody responses that neutralize divergent H1N1 and H3N2 viruses, opening new avenues to design improved vaccines.

Reference: A new class of antibodies that overcomes a steric barrier to cross-group neutralization of influenza viruses by Holly C. Simmons, Akiko Watanabe, Thomas H. Oguin III, Elizabeth S. Van Itallie, Kevin J. Wiehe, Gregory D. Sempowski, Masayuki Kuraoka, Garnett Kelsoe and Kevin R. McCarthy, 21 December 2023, PLOS Biology. DOI: 10.1371/journal.pbio.3002415

The research was supported by National Institute of Allergy and Infectious Diseases Program Project Grant P01 AI089618 (to G.H.K.) and funds from the University of Pittsburgh Center for Vaccine Research (to K.R.M).

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Scientists Discover New Class of Antibodies That Could Neutralize the Flu Virus - SciTechDaily

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Since the latest bout of avian flu was first detected in a commercial poultry flock two years ago, nearly 82 million chickens, ducks and turkeys have been killed to limit the spread of the virus.

That's because whole flocks or slaughterhouse lots are killed when a single diseased bird is found, says Northeastern food policy safety expert Darin Detwiler.

Within the last few weeks, a farm in California had to euthanize its 550,000 egg-laying hens when chickens tested positive for the avian flu, as reported by the Guardian and other news sources.

Detwiler says he expects commercial flocks will remain at risk since the rising demand for poultry and the rise of industrial poultry farms create conditions conducive to the spread of avian influenza, a highly pathogenic disease.

"It created this perfect storm," says Detwiler, an associate teaching professor of food policy. "It's just Russian roulette with a larger bull's eye."

Avian flu, a specific strain of influenza adapted to birds, "is nothing new," Detwiler says, adding that outbreaks between the 1950s and 1980s tended to be smaller and sporadic.

Times have changed, and "what we have to realize is that the poultry population has grown," Detwiler says. "The poultry population as a consumer food really grew in the 1990s. Therefore, bird populations grew radically and operations have become larger and larger."

He says 51 million poultry farm birds had to be "de-populated," using the U.S. Department of Agriculture's terminology, during the last big avian flu outbreak in 201415.

The latest outbreak was detected by the USDA in a commercial poultry flock on Feb. 8, 2022.

Since then, the USDA says, the virus has struck 1,084 commercial and backyard flocks in 47 states and led to the euthanization of nearly 81.74 million birds, mainly egg-laying chickens, broilers, turkeys and ducks.

One way USDA inspectors detect avian flu in poultry birds is to examine them just before slaughter for disease symptoms, including swelling, purple discoloration, paralysis or sickness, Detwiler says.

The detection of one sick chicken results in the entire lot of chickens being slaughtered and buried or burned according to USDA regulations, Detwiler says. Chickens back on the farm where the sick one originated are also killed, he says.

"In a large lot of chickens, if any one of them is found to show the symptoms of bird flu, they depopulate the entire flock."

"That's pretty much the only way you can control the disease," Detwiler says. "We're talking about exposure, contamination, transmission of disease and control of the flock.

"It's not like the flu is getting worse," he says. It's just that the size and scope of poultry farming is growing so large that bigger and bigger flocks of birds are killed when infections are detected, Detwiler says.

The Business Research Company predicts that the demand for poultry will grow 6.9% from 2023 to 2024, due in part to people's interest in healthy protein and to rising disposable incomes.

Massive poultry farms are opening to meet rising demand, with big poultry now raising "more than a billion birds annually in densely packed barns" in North Carolina, according to the Charlotte Observer.

The growth of massive poultry operations has resulted in complaints by neighbors, environmentalists and even poultry farmers, most of whom contract with multi-billion dollar companies including Tyson Foods and Perdue Farms, "which control almost all aspects of production," the Observer reported.

Sporadic cases of avian flu have occurred among people who handle birds, although there is no evidence of human-to-human transmission, according to the Centers for Disease Control and Prevention.

The National Chicken Council says avian flu is not a food-borne illness, although people are encouraged to eat only properly cooked and handled poultry.

The USDA says, "All poultry products for public consumption are inspected for signs of disease both before and after slaughter. The inspected for wholesomeness by the U.S. Department of Agriculture seal ensures the poultry is free from visible signs of disease."

Raw chicken is a culprit in salmonella but it could possibly pose a risk for avian flu as well, Detwiler says. He says the preemptive killing of "millions and millions" of birds shows that federal inspectors consider the risk of avian flu must be taken seriously.

Poultry farmers already are taking numerous steps to combat disease transmission, including having workers don hazmat-style suits, Detwiler says.

Poultry companies are looking at other ways to minimize the costs associated with flock eradication due to disease detection, including using hormones to grow larger chicken breasts and growing poultry cells in the lab, he says.

"I believe there's work underway to find some kind of vaccine (for avian flu)," he says.

"Then the goal would be to vaccinate chickens so that (flock eradication) doesn't happen at all," Detwiler says. "As of yet, it hasn't happened."

In the meantime, the USDA says cooking eggs and poultry to the proper temperature, preventing cross-contamination, sanitizing cutting boards and washing hands with warm soap and water for at least 20 minutes after handling raw poultry and eggs will provide "protection against all avian influenza viruses" as well as salmonella and E. coli.

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What's being done to keep avian flu out of the food supply chain? - Phys.org