Infectious disease experts say many people are not taking the latest Covid-19 wave in the US seriously enough and are not getting vaccinated or using antiviral drugs when sick, despite a summer wave that was larger and came earlier than anticipated.

Epidemiologists are saying that while symptoms of this wave are more mild than earlier strains, the virus remains a threat – particularly for older adults and people with underlying health conditions.

In response, public health officials are urging people to get a booster now – unless they recently had Covid, in which case they should wait three to four months – and to take a rapid test when sick. And if they have Covid, they should ask their doctors about antiviral treatments.

A nurse prepares a booster dose of the Moderna Covid-19 vaccine, Spikevax – a closeup of hands wearing surgical gloves drawing the vaccine from a small bottle into a syringe
Communicate risks of not getting Covid vaccine to boost uptake, study suggests
Read more
“There is a ton of Covid out there,” said Jennifer Nuzzo, an epidemiologist and director of the Pandemic Center at the Brown University School of Public Health. “If you’re experiencing any kind of symptoms, test yourself because you might benefit from getting medicine. At the very least, you can learn that you’re infected and stay home so you don’t give it to other people.”

Notably, the Covid viral activity in wastewater in August in the United States was almost twice as high as the same time last year and about the same as the peak of summer 2023, according to Centers for Disease Control and Prevention data. Still, hospitalizations and deaths are a fraction of what they were in 2022.

Updated COVID-19 vaccines are now available: They’re meant to give you the best protection against the strain of the virus that is making people severely sick now and even causing deaths.

Many people were infected during the persistent summer wave, which may leave you wondering when you should get the updated vaccine. The short answer is that it depends on when you last got infected or vaccinated and on your particular level of risk.

We heard from six experts—including medical doctors and epidemiologists—about when they recommend getting an updated vaccine. Read on to learn what they said. And to make it easy, check out the flowchart below.

It’s been about five months since the Texas Department of State Health Services announced that a worker on a dairy farm had tested positive for avian influenza A (H5N1) virus after being exposed to apparently infected cattle. Since then, the U.S. public health response has been slow and disjointed, bringing back memories of how the federal government responded during the early phase of the Covid-19 pandemic.

Despite having a pandemic playbook in early 2020, the U.S. appeared flat-footed in its response to Covid-19, including inadequate testing and unavailable personal protective equipment. And throughout the pandemic, mixed messaging on masks and later vaccines set back public health efforts.

As H5N1 circulates, it seems that lessons from Covid-19 remain unlearned. It appears that missteps are being made regarding testing, surveillance, transparency, and failure of communication and coordination throughout the health care system, the same kinds of things that hurt the response to Covid-19.

“The World Health Organization,” according to NPR, “considers the virus a public health concern because of its potential to cause a pandemic.” What may be concerning is that the genetic sequence of the Spanish flu that killed between 50 and 100 million people from 1918 to 1919 was later found to be an H1N1 virus that originated in birds and then somehow adapted to humans. And based on confirmed cases, the case fatality rate could be as high as 50 percent, as over the past two decades roughly half of about 900 people around the globe known to have contracted bird flu died from it. (There are two caveats, however: Due to limited testing, there were likely more cases that were undetected which would lower the mortality rate. And in the last two years, the global case fatality rate seems to have decreased.)

As of Aug. 30, the U.S. Department of Agriculture reports that 196 dairy cow herds in 14 U.S. states have confirmed cases of avian influenza.

COVID-19 hasn’t gone away, and data from the Centers for Disease Control and Prevention suggests it’s on the upswing around the country.

“We’ve seen these summer increases every summer that COVID-19 has been with us,” said Dr. Amesh Adalja, a Johns Hopkins University infectious disease physician. “What’s different about these cases this summer vs. prior summers is that they don’t translate into hospitals in crisis.”

Adalja said factors in the seasonal increase could be increased travel, people staying indoors to avoid summer heat and the virus’ continued evolution – which could help it get around people’s immunity.

Testing for COVID-19 is sporadic and the true number of cases isn’t clear because many infections aren’t reported. But one way to spot trends is to see what percentage of lab tests come back positive. By that metric, COVID-19 is surging.

As of 28 July 2024, a total of 14,250 cases of mpox (2,745 confirmed; 11,505 suspected) and 456 deaths have been recorded in 10 African countries, including Burundi, Cameroon, Central African Republic, Congo-Brazzaville, Democratic Republic of Congo (DRC), Ghana, Liberia, Nigeria, Rwanda and South Africa.

The DRC outbreak, ongoing since 2022, accounts for more than 90% of the reported cases of severe mpox clade 1b. This year, the DRC identified 13,791 cases, with children under 15 accounting for 68% of cases and 85% of deaths.

Four countries – Burundi, Kenya, Rwanda and Uganda – previously unaffected by mpox, have reported cases since mid-July 2024 (at least 50 confirmed cases, with clade 1b now confirmed in Kenya, Rwanda and Uganda).

There is a vaccine that is effective against both clades, but it is not widely available. The resources to contain and avoid this unfolding crisis exist but must be brought to bear to contain the outbreak with the greatest urgency possible.

This zoonotic virus, endemic to the forested regions of east, central and west Africa, has shown increased human-to-human transmission, including by way of sexual transmission, which deviates from the historically zoonotic (animal) nature of the disease.

Kenya’s Ministry of Health confirmed an outbreak of mpox clade 1b on 29 July 2024, originating from a traveller moving through Uganda and Rwanda. The development underscored the urgent need for enhanced public health measures across east Africa, as the high mobility of populations through key transport corridors poses a significant risk for regional transmission.

Four years after SARS-CoV2 sparked a devastating global pandemic, U.S. health officials now consider COVID-19 an endemic disease.

"At this point, COVID-19 can be described as endemic throughout the world," Aron Hall, the deputy director for science at the CDC's coronavirus and other respiratory viruses division, told NPR in an interview.

That means, essentially, that COVID is here to stay in predictable ways.

The classification doesn't change any official recommendations or guidelines for how people should respond to the virus. But the categorization does acknowledge that the SARS-CoV2 virus that causes COVID will continue to circulate and cause illness indefinitely, underscoring the importance of people getting vaccinated and taking other steps to reduce their risk for the foreseeable future.

There’s no way to put a price on the pain and suffering prevented by childhood vaccines. But as it turns out, you can pinpoint the savings to the country.

For nearly three decades, childhood vaccines — including those that target measles, tetanus and diphtheria — have saved the United States $540 billion in health care costs, according to a new report from the Centers for Disease Control and Prevention.

Routine childhood vaccinations have prevented approximately 508 million cases of illness, 32 million hospitalizations and 1,129,000 deaths, the agency estimated on Thursday.

“These vaccine programs, when you create the right infrastructure to implement them, they pay for themselves right away,” said William Padula, a health economist at the University of Southern California who was not involved in the new research.

The savings estimate includes money that would have been spent on treating the initial infection and managing later, related conditions. The figure dwarfs the cost of developing the shots.

But vaccine-preventable illnesses can also cause indirect economic effects if children become permanently disabled from an infection, or parents miss work while caring for their sick children.

When factoring in those costs, the C.D.C. bumped the estimated savings to $2.7 trillion.

Dr. Padula said those figures are on par with savings from medical breakthroughs like curing hepatitis C, or major pieces of public health legislation like the Clean Air Act.

Despite the considerable health and economic benefits, attitudes toward childhood vaccines are shifting. A Gallup poll published earlier this week found that just 40 percent of Americans think it’s important for children to get vaccinated, down from about 64 percent in 2001.

How Dangerous is Avian Flu, Officially Known as “Highly pathogenic avian influenza A H5N1 clade 2.3.4.4b genotype B3.13.”?

Dr. Jennifer Nuzzo, a senior fellow for global health at the Council on Foreign Relations (CFR), and Dr. Rick Bright, former CEO of the Pandemic Prevention Institute at the Rockefeller Foundation and director of the Biomedical Advanced Research and Development Authority (BARDA) recently discussed the growing risk of avian influenza spreading in North America among poultry, dairy cows – and a small number of farm workers in direct contact with infected animals.

Dr. Nuzzo reminds us that this disease, called Highly Pathogenic Avian Influenza (HPAI) influenza virus H5N1, is a closely related strain of the H1N1 influenza A virus that infected an estimated 500 million people worldwide during the Spanish Flu pandemic of 1918-1920 – resulting in an estimated 17 to 50 million people dying from the virus

BIRD FLU CHECK-IN — More cows and humans continue to test positive for avian influenza, but the CDC maintains that the risk to the public remains low.

We checked in with several infectious disease experts to learn more about what the recent outbreak at poultry farms in Colorado means for the U.S. response to the virus.

There have been several infections at two poultry farms in Colorado. What should the public take away from these cases?

Jennifer Nuzzo, a professor of epidemiology and director of the Pandemic Center at Brown University School of Public Health: “The number of cases that we’re seeing in Colorado, and the involvement of a large number of people with symptoms at the same time at multiple farms, screams at us that this virus is not going away — that this is becoming a recurring hazard for farmworkers.”

For nearly four months, the spread of bird flu in the nation’s dairy cattle has stoked fears that, if left unchecked, the virus could eventually unleash a pandemic.

The recent cluster of human cases connected to poultry farms in Colorado only underscores that the threat remains real.

Genetic sequencing of the virus collected from the sickened poultry workers closely resembles what’s circulating in dairy herds, suggesting that cattle somehow introduced the virus into the poultry flock.

At one massive poultry facility, workers culled the birds under particularly dangerous circumstances.

The outdoor temperature flirted with 100 degrees and heat advisories blanketed the region earlier this month as workers arrived at a commercial poultry operation in Weld County to start killing chickens.

Of the 1.8 million egg-laying hens inside the operation’s barns, at least some were infected with highly pathogenic avian influenza — bird flu. The strain of the virus that is now circling the globe has shown a remarkable ability to infect all kinds of animals, from seals to skunks to mountain lions. But it spreads most rapidly and lethally in wild birds and domestic poultry.

When a commercial flock is infected, standard practice is grim but efficient: Kill all the birds at the farm, devastating one operation in the hopes of stopping the virus and sparing the rest of the industry. By the time the workers in Weld County were done, though, some discovered that the virus had survived at least for one infection longer. It had found a new host: Their own bodies.

JUST HOW deadly is the H5N1 avian flu? The virus, which is currently sweeping through U.S. dairy herds, rarely jumps to human beings, at least for now. But when it does the consequences can be grave: The World Health Organization reports that 52 percent of people known to be infected with H5N1 have died from the disease.

The figure has been widely cited in academic papers, public health communications, and media reports, where it can provoke apocalyptic visions. “Bird flu pandemic could be ‘100 times worse’ than COVID,” claimed one New York Post headline. An article in The Guardian leads with the WHO’s “enormous concern” about the spread of H5N1, which, according to one lead scientist quoted, has an “‘extraordinarily high” human mortality rate.

The Race to Protect Condors Against Bird Flu

The actual picture, while still alarming, is more complicated. The WHO’s H5N1 mortality figure, an average of wildly different death rates from past outbreaks, doesn’t factor in mild cases that went undetected. Even less certain is how lethal H5N1 would be if it evolves to spread not just from animals to humans, but also from person to person.

The first step in combating any infectious disease outbreak is detection. Without widespread testing, health officials have little sense of who is infected, when to treat patients and how to monitor their close contacts.

In that sense, the bird flu outbreak plaguing the nation’s dairy farms is spreading virtually unobserved.

As of Monday, the virus had infected 157 herds in 13 states. But while officials have tested thousands of cows and are monitoring hundreds of farmworkers, only about 60 people have been tested for bird flu.

Officials do not have the authority to compel workers to get tested, and there is no way for workers to test themselves. In the current outbreak, just four dairy workers and five poultry workers have tested positive for H5N1, the bird flu virus, but experts believe that many more have been infected.

Five people who work at a poultry farm in northeastern Colorado have tested positive for the bird flu, the Colorado public health department reported July 14. (One of the cases awaits confirmation by the federal Centers for Disease Control and Prevention.) This brings the known number of U.S. cases this year to nine.

USE OUR CONTENT
It can be republished for free.

The workers were likely infected by chickens, which they had been tasked with killing in response to a bird flu outbreak at the farm. The endeavor occurred amid a heat wave, as outside temperatures soared to 104 degrees Fahrenheit.

“The barns in which culling occurs were no doubt even hotter,” said CDC principal deputy director Nirav Shah at a July 16 press briefing. Wearing N95 respirators, goggles, and other protective gear was a challenge. Industrial fans whipped feathers around the facility that could have carried the virus, Shah added.

In this environment, the farmworkers collected hundreds of chickens by hand and placed them into carts where they could be killed by carbon dioxide gas within two minutes.

Dairy farmworkers often spend 10 to 12 hours a day milking dairy cattle in crowded, wet environments. They are in constant, intimate contact with unpasteurized cow milk, a known carrier of H5N1, the viral strain of bird flu that jumped from poultry to cows back in March.

But despite being the most exposed population to the virus, farmworkers are also offered few protections. To prevent the spread of bird flu among the general public, experts say we need to first protect the health of farmworkers.

“I don't want us to ignore what is happening right now, which is that farmworkers are getting infected with this virus,” said Jennifer Nuzzo, an epidemiologist at Brown University.

As bird flu spreads among dairy cattle in the U.S., veterinarians and researchers have taken note of Finland’s move to vaccinate farmworkers at risk of infection. They wonder why their government doesn’t do the same.

“Farmworkers, veterinarians, and producers are handling large volumes of milk that can contain high levels of bird flu virus,” said Kay Russo, a livestock and poultry veterinarian in Fort Collins, Colorado. “If a vaccine seems to provide some immunity, I think it should be offered to them.”

As bird flu spreads among dairy cattle in the U.S., veterinarians and researchers have taken note of Finland’s move to vaccinate farmworkers at risk of infection. They wonder why their government doesn’t do the same.

Excerpt: "We're flying blind," said Jennifer Nuzzo, director of the Pandemic Center at the Brown University School of Public Health. With so few tests run, she said, it's impossible to know how many farmworkers have been infected or how serious the disease is. A lack of testing means the country might not notice if the virus begins to spread between people — the gateway to another pandemic.

Excerpt: And while the federal government has made efforts to try to bolster the stockpile of supplies, “there hasn’t been a lot of transparency. It’s hard to gauge the sufficiency of it,” said Jennifer B. Nuzzo, director of the Pandemic Center at the Brown University School of Public Health.

Guest essay by Jennifer Nuzzo, excerpt: How worried you should be about H5N1, the bird flu virus spreading on dairy farms in the United States, depends on whom you are.

The Centers for Disease Control and Prevention has described the current H5N1 risk to the general public as low. The risk that the virus poses is tempered by the fact that it doesn’t spread easily among people — yet.

Right now public-health experts have the difficult task of urging authorities who can do something about H5N1 to take action, while maintaining public trust. Americans have just been through a pandemic that resulted in over one million U.S. lives lost. They may feel weary of more bad news or fear-based messaging. Communicating that while the threat level for most people is low, but if nothing is done it could become quite high, is not easy but is important.

Excerpt: “The concern about H5N1 has always been there,” said Dr. Jennifer Nuzzo, professor of epidemiology and director of the Pandemic Center at the Brown University School of Public Health. “But in the last couple of years, [the virus] started doing things that have been a bit unusual.”

“We’ve seen this virus start to infect mammals and a wide range of mammals,” she said, pointing at the different outbreaks throughout the world. “That’s a concern because humans are mammals, and so mammals are more like us than birds are.”

But what makes this recent outbreak the most concerning for Nuzzo is that the virus is now capable of infecting cows. “Cows are mammals that humans have a lot more contact with than all the other mammals that we’ve seen get infected,” she said.

Analyses by Jennifer Nuzzo, Jorge Ledesma, and others.

Excerpt: “My highest level of concern right now is for the workers on the farms, who we know are being exposed to this virus and we know are already getting sick with this virus,” said Jennifer Nuzzo, director of the Pandemic Center at the Brown University School of Public Health. “We need to be talking more about protecting the workers who are in harm’s way today.”

Excerpt: Seth Berkley, a longtime and widely respected global health leader, said Thursday that it has been “shocking to watch the ineptitude” of the U.S. response to the avian influenza outbreak among dairy cattle, adding his voice to a chorus of critics.

In a presentation in London about vaccine development, Berkley, the former CEO of Gavi, the Vaccine Alliance, raised the issue of H5N1 bird flu when discussing whether the world was ready for another pandemic following its experience with Covid-19.

Webinar hosted by USC Anneberg Center for Health Journalism which featured Jennifer Nuzzo as a panelist.

The Initiative's website collects hundreds of Pandemic Lamplighter stories and lessons learned from their innovation and ingenuity in the face of pandemic darkness

Opinion piece from Asa Hutchinson (fmr Governor of Arkansas) and Deval Patrick (fmr Governor of Massachusetts) on the American Democracy and Health Security Initiative.

Provides urgent recommendations for preparedness & response. Findings to be released June 5th.

Biosecurity Readiness through Intelligence, Data, and Global Engagement Alliance

Excerpt: “The Centre for Disease Control laboratory is one of a few labs where eye specimens can be tested for H5N1 – this needs to be fixed, easier access to eye swab testing is needed to protect and diagnose farm workers,” said Dr Jennifer Nuzzo, Director of the Pandemic Centre and Professor of Epidemiology at the Brown University on X (formerly Twitter).

Excerpt: Jennifer Nuzzo, director of the Pandemic Center at Brown University’s School of Public Health, said she wished other states were looking for H5N1 cases as aggressively as Michigan is.

“If there’s any takeaway from this finding it’s that this is probably the tip of the iceberg because this is the one state that we know of that has done the most in terms of testing on farms of both cows and also monitoring workers that are on the farms where they found cattle infections,” she told STAT.

Excerpt: Jennifer Nuzzo, director of the Pandemic Center at the Brown University School of Public Health, said she was glad to hear that the CDC is pushing for continued flu surveillance.

“So many of our data points and response options are predicated on being able to find cases, and there are currently many holes in our ability to do that,” Nuzzo said.

Excerpt: “The more this virus circulates, the more there is a chance for mutations,” said Dr. Jennifer Nuzzo, a professor of epidemiology who directs the Pandemic Center at the Brown University School of Public Health. And more mutations could mean a bigger risk of the virus becoming highly infectious among more people.

Excerpt: “We have no idea if this virus is going to evolve to become a pandemic strain but we know today that farmworkers are being exposed and we have good reason to think that they are getting sick,” said Jennifer Nuzzo, director of the Pandemic Center at Brown University School of Public Health

Here & Now's Peter O'Dowd speaks with epidemiologist Jennifer Nuzzo about the bird flu that has recently sickened dairy cows in several states but so far only one dairy worker in Texas.

Professor Jennifer Nuzzo, epidemiologist and director of the Pandemic Center at the Brown University School of Public Health, joins host Megan Hall for a timely update on the recent outbreaks of H5N1 Bird Flu.

Jennifer Nuzzo is a co-author of this piece, published in PLOS Global Public Health, featuring work for the Exemplars in Global Health program.

Opinion piece cowritten by Jennifer Nuzzo.

Excerpt: The discovery of bird flu virus particles in milk has moved the federal government to take more aggressive action to prevent the further spread of H5N1 on dairy farms. The Agriculture Department has rightly issued new testing recommendations meant to keep the virus from spreading across state lines. But this additional testing will do little to address the primary threat that H5N1 poses to humans: the infection of farmworkers. Our failure to protect them threatens their health and gives the virus an opportunity to evolve into a greater threat to people, including those who live far from dairy farms.

Excerpt: "It does feel like Ground Hog Day," said Jennifer Nuzzo, who heads Brown University's Pandemic Center. "We still seem to be stuck in reactive mode. We shouldn't be waiting for evidence that the virus is devastating us. We should be trying to act now to prevent the virus from devastating us."

Excerpt: But it's still not clear exactly where the flu virus has spread or what it's capable of, said several experts, including Jennifer Nuzzo, a professor of epidemiology and director of the Pandemic Center at the Brown University School of Public Health.

"Our surveillance is inadequate to know where this virus is and where it isn't, which is critical for protecting farmworkers and people involved in the dairy industry ‒ but also important for staying ahead of this virus to prevent a future pandemic," Nuzzo said.

Excerpt: “More testing is better,” said Jennifer Nuzzo, an epidemiologist and director of Brown University’s Pandemic Center. “But in many ways this policy is very leaky in terms of how much virus it will allow to move. And because we still don’t know what’s driving transmission between cows, we should not pin our hopes on this policy making a major dent in the infections we’re seeing.”

Excerpt: “Our job right now is to protect farmworkers,” said Jennifer Nuzzo, director of the Pandemic Center at Brown University School of Public Health. “We can’t do that unless we know where the virus is or where it isn’t.”

Excerpt: Some public health experts are concerned about how long that testing is taking — and the lack of transparency thus far about the government’s findings. Jennifer Nuzzo, director of the Pandemic Center at the Brown University School of Public Health, questioned why the FDA did not immediately say it would test milk products and expeditiously culture any potential virus fragments found.

“Just from a government credibility standpoint, being transparent about what you’re doing, it’s important,” Nuzzo said.

Excerpt: To really understand the scale of spread as well as possible mechanisms of viral transmission, it’s necessary to conduct widespread testing of animals with and without symptoms, said Jennifer Nuzzo, an epidemiologist and director of Brown University’s Pandemic Center. “If we’re only testing cows with outward symptoms, we’re missing infections in those without.”

Excerpt: So let's start with the latest update, particles of this virus found in commercial pasteurized milk. How concerned should the everyday consumer be?

Dr. Jennifer Nuzzo, Brown University School of Public Health: I don't have any reason to be concerned at this point.

Finding evidence of genetic material, which is what the test results told us, by itself is not alarming. In order to know if the virus will infect us, we have to do a different kind of test. And this test was not that. They're actually undergoing those tests now.

But I don't have any reason to think that we will be harmed, because we use pasteurization. And I have no reason to think that the H5N1 virus is any different from all the other pathogens that we think could be in milk. Pasteurization doesn't remove the genetic material of those pathogens, but it changes the pathogens and either kills or it activates them, so that they can't infect us...

Excerpt: The Food and Drug Administration on Tuesday said it had been testing milk samples throughout the dairy production process and confirmed the detection of viral particles “in some of the samples,” but declined to provide details.

The presence of genetic fragments of the virus in milk is not unexpected. Pasteurization typically works to inactivate pathogens, said Jennifer Nuzzo, director of the Pandemic Center at the Brown University School of Public Health. Pasteurization generally does not remove genetic material, but it typically renders pathogens unable to cause harm to people, Nuzzo said.

Excerpt: For decades, public health experts have warned of the danger of H5N1, also known as the avian flu, crossing over to humans. That fear became a reality when earliest this month, a dairy farm worker in Texas tested positive for the highly pathogenic avian influenza. This is the first reported cow-to-human spread of the virus. The U.S. has only ever recorded a handful of cases but there is mounting concern that mutations in the virus will allow it to spread to more mammals and possibly, more people. Are we ready for an influenza pandemic of this kind? Joining us today on AirTalk to talk about this latest outbreak and the threat it poses to humans is Jennifer Nuzzo, Professor of Epidemiology and Director of the Pandemic Center at Brown University.

Brown University Pandemic Center leader honored for outstanding humanitarian efforts and achievements in the field of global public health

Excerpt: For a virus to have pandemic potential, it needs to be able to pass easily from person-to-person. H5N1 does not have the ability to do so, but scientists fear it could develop this feature.

“The bigger picture is that this virus is not cooling off,” CFR Senior Fellow Jennifer Nuzzo told Politico. “We’ve been worrying about this virus for twenty years, more than twenty years. And in the last year, it has really been remarkable in how far across the globe it has been spreading, and how many species it’s been affecting.”