influenza

us-prepares-for-bird-flu-pandemic-with-$176m-moderna-vaccine-deal

US prepares for bird flu pandemic with $176M Moderna vaccine deal

Pandemic fears —

Phase 3 trial is expected to begin next year.

US prepares for bird flu pandemic with $176M Moderna vaccine deal

The US government will pay Moderna $176 million to develop an mRNA vaccine against a pandemic influenza—an award given as the highly pathogenic bird flu virus H5N1 continues to spread widely among US dairy cattle.

The funding flows through BARDA, the Biomedical Advanced Research and Development Authority, as part of a new Rapid Response Partnership Vehicle (RRPV) Consortium. The program is intended to set up partnerships with industry to help the country better prepare for pandemic threats and develop medical countermeasures, the Department of Health and Human Services said in a press announcement Tuesday.

In an announcement of its own Tuesday, Moderna noted that it began a Phase 1/2 trial of a pandemic influenza virus vaccine last year, which included versions targeting H5 and H7 varieties of bird flu viruses. The company said it expects to release the results of that trial this year and that those results will direct the design of a Phase 3 trial, anticipated to begin in 2025.

The funding deal will support late-stage development of a “pre-pandemic vaccine against H5 influenza virus,” Moderna said. But, the deal also includes options for additional vaccine development in case other public health threats arise.

“mRNA vaccine technology offers advantages in efficacy, speed of development, and production scalability and reliability in addressing infectious disease outbreaks, as demonstrated during the COVID-19 pandemic,” Moderna CEO Stéphane Bancel said in the announcement. “We are pleased to continue our collaboration with BARDA to expedite our development efforts for mRNA-based pandemic influenza vaccines and support the global public health community in preparedness against potential outbreaks.”

US health officials have said previously that they were in talks with Moderna and Pfizer about the development of a pandemic bird flu vaccine. The future vaccine will be in addition to standard protein-based bird flu vaccines that are already developed. In recent weeks, the health department has said it is working to manufacture 4.8 million vials of H5 influenza vaccine in the coming months. The plans come three months into the H5N1 dairy outbreak, which is very far from the initial hopes of containment.

Botched response

The US is badly fumbling its response to the unprecedented outbreak, drawing criticism from US-based and international experts alike. Genetic analyses suggest that the virus has been spreading among the country’s dairy cattle since late last year. But, it wasn’t until months later, on March 25, that the US Department of Agriculture confirmed the first four infected herds in two states (Texas and Kansas). Since then, the outbreak has spread to around 140 herds in 12 states—at least.

Some farms are refusing to test, and experts expect that there is a significant number of undocumented herd infections, particularly given the widespread detection of inactivated H5N1 in the commercial milk supply. Further, of the 140 herds with documented infections, federal officials do not know how many are still actively infected rather than recovered. It is unclear if infected cows can become reinfected, and if so, how quickly after an infection.

While the risk to the general public is considered to be low currently, farm workers are at higher risk of contracting the infection. To date, there have been three confirmed infections among dairy farm workers—one in Texas and two in Michigan, which has had a uniquely robust response to the outbreak. Still, with hundreds to thousands of farm workers at risk of contracting the virus, only 53 people in the country to date have been tested for H5 influenza.

In a presentation in London last month, global health leader Seth Berkley said it was “shocking to watch the ineptitude” of the US response to the H5N1 outbreak. He, like other experts, questioned whether the US public health community has learned or improved from the failures of the COVID-19 pandemic.

Similar to problems during the pandemic, a key barrier to the H5N1 response is resistance from farmers and farm workers to partner with state and federal health officials. Federal agencies have limited authority within states, but they have announced an array of assistance programs for dairy farms, including compensatory funding and access to personal protective equipment for farm workers. They have also issued guidance and restrictions to tighten biosecurity measures. But there has been little voluntary participation on both fronts.

For instance, officials figured out early in the outbreak that movement of cattle, workers, and equipment between farms is the main way H5N1 is spreading among dairies. In April, the USDA required testing of a portion of cows prior to their movement across state lines. But movement within states is governed by states. In a survey last month, which captured data from 54 percent of affected farms at the time, more than 60 percent of farmers said they continued to move cattle off their infected farms after the onset of clinical signs of infection in their animals.

The more the virus expands its footprint across US dairy farms, adapts to its newfound mammalian host, and comes in contact with humans, the more and more chances it has to leap to humans and gain the ability to spread among us.

In HHS’s Tuesday announcement of the Moderna award, Dawn O’Connell, assistant secretary for Preparedness and Response, spoke to the growing concern that the H5N1 outbreak could spark another pandemic. “The award made today is part of our longstanding commitment to strengthen our preparedness for pandemic influenza,” O’Connell said. “Adding this technology to our pandemic flu toolkit enhances our ability to be nimble and quick against the circulating strains and their potential variants.”

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As bird flu spreads in cows, US close to funding Moderna’s mRNA H5 vaccine

New jab —

If trials are successful, US government likely to buy doses for vaccine stockpile.

Testing for bird flu, conceptual image

Digicom Photo/Science Photo Library via Getty

The US government is nearing an agreement to bankroll a late-stage trial of Moderna’s mRNA pandemic bird flu vaccine, hoping to bolster its pandemic jab stockpile as an H5N1 outbreak spreads through egg farms and among cattle herds.

The federal funding from the government’s Biomedical Advanced Research and Development Authority, known as BARDA, could come as early as next month, according to people close to the discussions.

It is expected to total several tens of millions of dollars and could be accompanied by a commitment to procure doses if the phase-three trials are successful, they said.

Talks between the government and Pfizer over supporting the development of its mRNA vaccine targeting the H5 family of viruses are also ongoing. Pfizer, like Moderna, played a pivotal role in supplying mRNA vaccines for Washington’s jab rollout during the COVID-19 pandemic.

Bird flu has been detected on poultry farms in 48 states and in dairy cow herds across nine states as part of one of the worst outbreaks in recent history, according to the US Centers for Disease Control and Prevention. The CDC has also reported two cases affecting dairy workers in recent months, adding to concerns of the virus spreading in human populations.

US health authorities continue to classify the public health risk from bird flu as low, but their efforts to build up and diversify the pandemic vaccine stockpile have gathered pace. Federal health officials said last week that the government was moving ahead with plans to fill 4.8 million vials from its existing portfolio of protein-based bird flu vaccines and was in discussions with Moderna and Pfizer.

The possibility of contributing to the US pandemic vaccine stockpile also represents a commercial opportunity for the mRNA vaccine makers, whose market valuations have fallen significantly from pandemic highs. Moderna’s share price is up nearly 37 percent since the start of April.

Moderna has completed dosing of a mid-stage trial of its H5 pandemic flu vaccine, with interim data expected soon. Pfizer said in a statement on Wednesday that it “would be prepared to deploy the company’s capabilities to develop a vaccine for strategic stockpiles,” confirming that it had launched a phase-one trial for a pandemic flu vaccine last December.

Applications for BARDA grant funding for an mRNA-based pandemic flu vaccine closed in December last year, according to a project proposal seen by the Financial Times. But the bird flu outbreak has increased the urgency of talks, with federal officials acknowledging that the speed with which mRNA vaccines were designed and deployed during the COVID-19 pandemic showed their value compared with more traditional vaccine technology.

The jabs from GSK, Sanofi, and CSL Seqirus, which make up the US government’s existing pandemic vaccine portfolio, provide immunity to the current strain of bird flu, according to laboratory testing, but rely on a more time-intensive manufacturing process using egg- and cell-based cultures.

The US health department, Moderna, and Pfizer declined to comment on the potential funding.

© 2024 The Financial Times Ltd. All rights reserved. Not to be redistributed, copied, or modified in any way.

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Cats suffer H5N1 brain infections, blindness, death after drinking raw milk

Spillover —

Mammal-to-mammal transmission raises new concerns about the virus’s ability to spread.

Farm cats drinking from a trough of milk from cows that were just milked.

Enlarge / Farm cats drinking from a trough of milk from cows that were just milked.

On March 16, cows on a Texas dairy farm began showing symptoms of a mysterious illness now known to be H5N1 bird flu. Their symptoms were nondescript, but their milk production dramatically dropped and turned thick and creamy yellow. The next day, cats on the farm that had consumed some of the raw milk from the sick cows also became ill. While the cows would go on to largely recover, the cats weren’t so lucky. They developed depressed mental states, stiff body movements, loss of coordination, circling, copious discharge from their eyes and noses, and blindness. By March 20, over half of the farm’s 24 or so cats died from the flu.

In a study published today in the journal Emerging Infectious Diseases, researchers in Iowa, Texas, and Kansas found that the cats had H5N1 not just in their lungs but also in their brains, hearts, and eyes. The findings are similar to those seen in cats that were experimentally infected with H5N1, aka highly pathogenic avian influenza virus (HPAI). But, on the Texas dairy farm, they present an ominous warning of the potential for transmission of this dangerous and evolving virus.

The contaminated milk was the most likely source of the cat’s fatal infections, the study authors concluded. Although it can’t be entirely ruled out that the cats got sick from eating infected wild birds, the milk they drank from the sick cows was brimming with virus particles, and genetic data shows almost exact matches between the cows, their milk, and the cats. “Therefore, our findings suggest cross-species mammal-to-mammal transmission of HPAI H5N1 virus and raise new concerns regarding the potential for virus spread within mammal populations,” wrote the authors, who are veterinary researchers from Iowa, Texas, and Kansas.

The early outbreak data from the Texas farm suggests the virus is getting better and better at jumping to mammals, and data from elsewhere shows the virus is spreading widely in its newest host. On March 25, the US Department of Agriculture confirmed the presence of H5N1 in a dairy herd in Texas, marking the first time H5N1 had ever been known to cross over to cows. Since then, the USDA has tallied infections in at least 34 herds in nine states: Texas, Kansas, Michigan, New Mexico, Idaho, Ohio, South Dakota, North Carolina, and Colorado.

The Food and Drug Administration, meanwhile, has detected genetic traces of H5N1 in roughly 20 percent of commercial milk samples. While commercial milk is still considered safe—pasteurization is expected to destroy the virus and early testing by the FDA and other federal scientists confirms that expectation—the finding suggests yet wider spread of the virus among the country’s milk-producing cows.

Cows are only the latest addition to H5N1’s surprisingly broad host range. Amid a global outbreak over the past several years that has devastated wild bird populations and poultry farms, researchers have documented unexpected and often deadly outbreaks in mammals. Since 2022, the USDA has found H5N1 in over 200 mammals, from big cats in zoos to harbor seals, mountain lions, raccoons, skunks, squirrels, polar bears, black bears, foxes, and bottlenose dolphins.

“The recurring nature of global HPAI H5N1 virus outbreaks and detection of spillover events in a broad host range is concerning and suggests increasing virus adaptation in mammals,” the authors wrote. “Surveillance of HPAI viruses in domestic production animals, including cattle, is needed to elucidate influenza virus evolution and ecology and prevent cross-species transmission.”

In the meantime, it’s definitely not the time to start drinking raw cow’s milk. While drinking raw milk is always dangerous because it carries the threat of various nasty bacterial infections, H5N1 also appears to be infectious in raw milk. And, unlike other influenza viruses, H5N1 has the potential to infect organs beyond the lungs and respiratory tract, as seen in the cats. The authors of the new study note that a 2019 consumer survey found that 4.4 percent of adults in the US consumed raw milk more than once in the previous year, suggesting more public awareness of the dangers of raw milk is necessary.

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Fragments of bird flu virus genome found in pasteurized milk, FDA says

Milk testing —

The test cannot tell if the virus is live. The FDA still assess milk supply as safe.

Cows being milked

Enlarge / Cows being milked

The Food and Drug Administration on Tuesday announced that genetic fragments from the highly-pathogenic avian influenza virus H5N1 have been detected in the pasteurized, commercial milk supply. However, the testing completed so far—using quantitative polymerase chain reaction (qPCR)—only detects the presence of viral genetic material and cannot tell whether the genetic material is from live and infectious viral particles or merely remnants of dead ones killed by the pasteurization process.

Testing is now ongoing to see if viable, infectious H5N1 can be identified in milk samples.

So far, the FDA still believes that the milk supply is safe. “To date, we have seen nothing that would change our assessment that the commercial milk supply is safe,” the agency said in a lengthy explanation of the finding and ongoing testing.

H5N1 made its startling jump to US dairy cows recently, with the first ever documented cases in a Texas herd confirmed on March 25. It has spread widely since then with at least 32 herds in eight states now known to be infected. The unexpected spread to bovines has raised fears that the virus is evolving to infect mammals more efficiently, and so poses a heightened risk of spread to and among humans.

But amid the alarming outbreak among the country’s dairy herds, federal agencies have appeared confident that the virus poses little risk to no risk to the safety of the milk supply.

“At this time, there continues to be no concern that this circumstance poses a risk to consumer health, or that it affects the safety of the interstate commercial milk supply because products are pasteurized before entering the market” the FDA wrote in an FAQ published Friday. “Pasteurization has continually proven to inactivate bacteria and viruses, like influenza, in milk.”

In the announcement Tuesday, the FDA also highlighted that multiple studies have shown that the pasteurization process for eggs, which uses lower temperatures than what is used for milk, is effective at inactivating H5N1.

Nevertheless, the FDA, along with the Centers for Disease Control and Prevention and the US Department of Agriculture, have continued to investigate potential risks, including establishing whether pasteurization can inactivate this specific virus. The FDA noted in its announcement Tuesday that, while pasteurization is expected to kill the virus, pasteurization is “different than complete sterilization.”

As such, it carried out the qPCR tests, expecting it might find some genetic fragments in the pasteurized milk because virus has been detected in raw milk. “Based on available information, pasteurization is likely to inactivate the virus, however the process is not expected to remove the presence of viral particles,” the FDA explained. “Therefore, some of the samples collected have indicated the presence of HPAI [Highly Pathogenic Avian Influenza] using quantitative polymerase chain reaction (qPCR) testing.”

The FDA did not indicate how many samples it has tested, where the samples were collected from, or the level of viral genetic material the samples contained.

The agency is now working on assessing whether it can identify if any virus particles are infectious using egg inoculation tests, which are considered a gold-standard for determining viral viability. It added that it will release results from those tests and others in “the next few days to weeks.”

“[W]e take this current situation and the safety of the milk supply very seriously. We recognize the importance of releasing further, actionable information,” the FDA said.

Meanwhile, the agency reported that the CDC’s food safety group has been closely monitoring emergency department data and flu testing data for any unusual trends in flu-like illness, flu, or conjunctivitis, which could indicate spread of H5N1 to people. “To date, surveillance systems do not show any unusual trends or activity,” the FDA said.

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Bird flu flare: Cattle in 5 states now positive as Texas egg farm shuts down

flare-up —

The risk to the general public remains low, federal officials say.

Chicken eggs are disposed of at a quarantined farm with bird flu in Israel's northern village of Margaliot on January 3, 2022.

Enlarge / Chicken eggs are disposed of at a quarantined farm with bird flu in Israel’s northern village of Margaliot on January 3, 2022.

The flare-up of highly pathogenic bird flu continues to widen in US livestock after federal officials confirmed last week that the virus has spread to US cows for the first time. The virus has now been detected in dairy cows in at least five states, a single person in Texas exposed to infected cows, and an egg farm in Texas, all spurring yet more intense monitoring and biosecurity vigilance as the situation continues to evolve.

As of Tuesday, seven dairy herds in Texas, two in Kansas, and one each in Idaho, Michigan, and New Mexico had tested positive for the virus. The affected dairy herd in Michigan had recently received cows from one of the infected herds in Texas. It remains unclear if there is cow-to-cow transmission of the flu virus.

The virus—a highly pathogenic H5N1 avian influenza or HPAI—has been devastating wild birds worldwide for the past several years. Throughout the devastating outbreak, the flu virus has spilled over to various species, including big cats in zoos, river otters, bears, dolphins, seals, squirrels, and foxes. While cows were an unexpected addition to the list, federal officials noted last week that affected dairy farms had found dead wild birds on their farms, suggesting that wild birds introduced the virus to the cows, not an intermediate host.

On Monday, the Centers for Disease Control and Protection reported that a person in Texas who had contact with infected dairy cows had tested positive for the HPAI. The person’s only symptom was eye redness. The CDC said the person was treated with an antiviral for flu and was recovering. It is the second case of HPAI found in a person in the US. The first case was in a person in Colorado who was directly exposed to poultry infected with the virus. In that case, the person’s only symptom was fatigue over a few days. The person recovered. The CDC considers the risk of HPAI to the general public to be low.

Low risk

Meanwhile, the virus continues to spread to less-surprising animals: chickens. On Tuesday, Cal-Maine Foods, Inc., the country’s largest producer of fresh eggs, reported that HPAI was detected in one of its facilities in Texas. The facility is located in Parmer County, which sits at the border of Texas and New Mexico. It’s unclear if the egg facility is close to any of the affected dairy herds. Cal-Maine, following the US Department of Agriculture biosecurity protocols, immediately shut down the facility. Approximately 1.6 million hens and 337,000 pullets—young hens—were culled. Cal-Maine said the hens represented about 3.6 percent of the company’s total flock.

Since the outbreak began in wild birds, the virus has led to the deaths of over 82 million commercial and backyard birds in the US, with 48 states affected and over 1,000 outbreaks reported. The infections have spurred increases in egg and poultry prices.

It’s unclear if the virus will have the same effect on milk or beef, but so far, it appears that it will not. In the infected herds, the virus appears to only be affecting a small percentage of animals, particularly older animals, and they generally recover. As the USDA puts it there’s “little to no associated mortality reported.” Milk from sick cows is always diverted from the milk supply, but even if milk contaminated with HPAI were to make it into the supply, the virus would be destroyed in the pasteurization process.

Still, the continued, widespread outbreak and spillovers of HPAI in various species highlight the ever-present risk that influenza viruses could mix together, combining genetic fragments of different strains (genetic reassortment) to create a new strain that could spark outbreaks or even a pandemic in humans. In the current outbreak among dairy cattle, federal researchers were quick to check the genetic sequence of the HPAI, finding that, so far, the strain lacks mutations in key genetic regions that would signal the virus has become more infectious to humans. For now, the USDA and the CDC report that the risk to the public is low.

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cdc-ditches-5-day-covid-isolation,-argues-covid-is-becoming-flu-like

CDC ditches 5-day COVID isolation, argues COVID is becoming flu-like

New phase —

The agency released a unified “practical” guidance for respiratory viruses.

A view of the Centers for Disease Control and Prevention headquarters in Atlanta.

Enlarge / A view of the Centers for Disease Control and Prevention headquarters in Atlanta.

COVID-19 is becoming more like the flu and, as such, no longer requires its own virus-specific health rules, the Centers for Disease Control and Prevention said Friday alongside the release of a unified “respiratory virus guide.”

In a lengthy background document, the agency laid out its rationale for consolidating COVID-19 guidance into general guidance for respiratory viruses—including influenza, RSV, adenoviruses, rhinoviruses, enteroviruses, and others, though specifically not measles. The agency also noted the guidance does not apply to health care settings and outbreak scenarios.

“COVID-19 remains an important public health threat, but it is no longer the emergency that it once was, and its health impacts increasingly resemble those of other respiratory viral illnesses, including influenza and RSV,” the agency wrote.

The most notable change in the new guidance is the previously reported decision to no longer recommend a minimum five-day isolation period for those infected with the pandemic coronavirus, SARS-CoV-2. Instead, the new isolation guidance is based on symptoms, which matches long-standing isolation guidance for other respiratory viruses, including influenza.

“The updated Respiratory Virus Guidance recommends people with respiratory virus symptoms that are not better explained by another cause stay home and away from others until at least 24 hours after both resolution of fever AND overall symptom are getting better,” the document states. “This recommendation addresses the period of greatest infectiousness and highest viral load for most people, which is typically in the first few days of illness and when symptoms, including fever, are worst.”

“Residual risk”

The CDC acknowledged that the eased isolation guidance will create “residual risk of SARS-CoV-2 transmission,” and that most people are no longer infectious only after 8 to 10 days. As such, the agency urged people to follow additional interventions—including masking, testing, distancing, hygiene, and improving air quality—for five additional days after their isolation period.

“Today’s announcement reflects the progress we have made in protecting against severe illness from COVID-19,” CDC Director Dr. Mandy Cohen said in a statement. “However, we still must use the commonsense solutions we know work to protect ourselves and others from serious illness from respiratory viruses—this includes vaccination, treatment, and staying home when we get sick.”

Overall, the agency argued that a shorter isolation period would be inconsequential. Other countries and states that have similarly abandoned fixed isolation times did not see jumps in COVID-19 emergency department visits or hospitalizations, the CDC pointed out. And most people who have COVID-19 don’t know they have it anyway, making COVID-19-specific guidance moot, the agency argued. In a recent CDC survey, less than half of people said they would test for SARS-CoV-2 if they had a cough or cold symptoms, and less than 10 percent said they would go to a pharmacy or health care provider to get tested. Meanwhile, “The overall sensitivity of COVID-19 antigen tests is relatively low and even lower in individuals with only mild symptoms,” the agency said.

The CDC also raised practical concerns for isolation, including a lack of paid sick leave for many, social isolation, and “societal costs.”

The points are likely to land poorly with critics.

“The CDC is again prioritizing short-term business interests over our health by caving to employer pressure on COVID guidelines. This is a pattern we’ve seen throughout the pandemic,” Lara Jirmanus, Clinical Instructor of Medicine at Harvard Medical School, said in a press release last month after the news first broke of the CDC’s planned isolation update. Jirmanus is a member of the People’s CDC, a group that advocates for more aggressive COVID-19 policies, which put out the press release.

Another member of the group, Sam Friedman, a professor of population health at NYU Grossman School of Medicine, also blasted the CDC’s stance last month. The guidance will “make workplaces and public spaces even more unsafe for everyone, particularly for people who are high-risk for COVID complications,” he said.

COVID and flu

But, the CDC argues that the threat of COVID-19 is fading. Hospitalizations, deaths, prevalence of long COVID, and COVID-19 complications in children (MIS-C) are all down. COVID-19 vaccines are safe and effective at preventing severe disease, death, and to some extent, long COVID—we just need more people to get them. Over 95 percent of adults hospitalized with COVID-19 in the 2023–2024 respiratory season had no record of receiving the seasonal booster dose, the agency noted. Only 22 percent of adults got the latest shot, including only 42 percent of people ages 65 and older. In contrast, 48 percent of adults got the latest flu shot, including 73 percent of people ages 65 and older.

But even with the crummy vaccination rates for COVID-19, a mix of past infection and shots have led to a substantial protection in the overall population. The CDC even went as far as arguing that COVID-19 deaths have fallen to a level that is similar to what’s seen with flu.

“Reported deaths involving COVID-19 are several-fold greater than those reported to involve influenza and RSV. However, influenza and likely RSV are often underreported as causes of death,” the CDC said. In the 2022–2023 respiratory virus season, there were nearly 90,000 reported COVID-19 deaths. For flu, there were 9,559 reported deaths, but the CDC estimates the true number to be between 18,000 and 97,000. In the current season, there have been 32,949 reported COVID-19 deaths to date and 5,854 reported flu deaths, but the agency estimates the real flu deaths are between 17,000 and 50,000.

“Total COVID-19 deaths, accounting for underreporting, are likely to be higher than, but of the same order of magnitude as, total influenza deaths,” the agency concluded.

In all, the CDC was ready to fold SARS-CoV-2 into the gang of common seasonal respiratory viruses, with most cases mild and undiagnosed. “Viruses cause most acute respiratory illnesses, but it is rarely possible to determine the type of virus without testing, and oftentimes testing does not change clinical management,” the agency wrote.

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cdc-reports-dips-in-flu,-covid-19,-and-rsv—though-levels-still-very-high

CDC reports dips in flu, COVID-19, and RSV—though levels still very high

a break? —

The dips may be due to holiday lulls and CDC is monitoring for post-holiday increase.

The influenza virus from an image produced from an image taken with transmission electron microscopy. Viral diameter ranges from around 80 to 120 nm.

Enlarge / The influenza virus from an image produced from an image taken with transmission electron microscopy. Viral diameter ranges from around 80 to 120 nm.

Key indicators of seasonal flu activity declined in the first week of the year, signaling a possible reprieve from the high levels of respiratory virus transmission this season—but the dip may only be temporary.

On Friday, the Centers for Disease Control and Prevention released its latest flu data for the week ending on January 6. Outpatient visits for influenza-like illnesses (ILI) were down that week, the first decline after weeks of rapid increases. Flu test positivity and hospitalizations were also down slightly.

Percent of outpatient visits for respiratory illnesses by week.

Enlarge / Percent of outpatient visits for respiratory illnesses by week.

But transmission is still elevated around the country. Fourteen states have ILI activity at the “very high” level in the current data, down from 22 the week before. And 23 states have “high” activity level, up from 19 the week before. (You can see the week-by-week progression of this year’s flu season in the US here.)

The CDC says it is monitoring for “a second period of increased influenza activity that often occurs after the winter holidays.”

Map of ILI activity by state.

Enlarge / Map of ILI activity by state.

Flu isn’t the only virus that seems to be letting up a little in the data, at least for now. COVID-19 data also showed some dips, with the CDC reporting that “Despite test positivity (percentage of tests conducted that were positive), emergency department visits, and hospitalizations remaining elevated nationally, the rates have stabilized, or in some instances decreased, after multiple weeks of continual increase.”

The CDC speculates that some of the declines in indicators could be due to people not seeking medical care during the holidays as they would otherwise. COVID-19 wastewater activity levels remain “very high,” with all regions showing high or increasing levels. The South and Midwest have the highest levels in the latest data, but there are some early indications that rises in the Midwest and Northeast may be slowing down.

Meanwhile, RSV activity remains elevated, though some areas are starting to see declines.

The CDC notes that it’s not too late to get vaccinated against COVID-19, flu, and (for those ages 60 and over) RSV. So far, 21 percent of adults have received the 2023–2024 COVID-19 vaccine, including 41.5 percent of people ages 65 and up. Around 363,000 people have died from COVID-19 in the US since September.

For flu, about 47 percent of adults have received their annual shot, including 74 percent of people ages 65 and up. On Thursday, researchers in Canada published the first estimates of flu vaccine effectiveness this season, finding the current annual shots are 61 percent effective against the most common strain of flu circulating in the US (influenza A(H1N1)pdm09) and 49 percent effective against the less common influenza A(H3N2) and 75 percent effective against influenza B.

The CDC estimates that there have been at least 14 million flu cases, 150,000 hospitalizations, and 9,400 deaths from flu so far this season so far, the agency reported. In the first week of this year, 13 children died of flu, bringing this season’s total to 40.

CDC reports dips in flu, COVID-19, and RSV—though levels still very high Read More »