Since the earliest days of the pandemic, health officials have gauged the threat of COVID-19 by comparing it to the flu.

At first, it wasn’t even close. People hospitalized in 2020 with the then-novel respiratory disease were five times more likely to die of their illness than were patients who had been hospitalized with influenza during the preceding flu seasons.

Immunity from vaccines and past coronavirus infections has helped tame COVID-19 to the point that when researchers compared the mortality rates of hospitalized COVID-19 and seasonal influenza patients during the height of the 2022-23 flu season, they found that the pandemic disease was only 61% more likely to result in death.

Now the same researchers have analyzed data for the the fall and winter of 2023 and 2024. Dr. Ziyad Al-Aly, director of the Clinical Epidemiology Center at the VA St. Louis Health Care System, and his colleagues expected to find that the two respiratory diseases had finally equalized.

“There’s a narrative out there that the pandemic is over, that it’s a nothingburger,” Al-Aly said. “We came into this thinking we would do this rematch and find it would be like the flu from now on.”

The VA team examined electronic health records of patients treated in Veterans Affairs hospitals in all 50 states between Oct. 1 and March 27. They zeroed in on patients who were admitted because they had fevers, shortness of breath or other symptoms due to either COVID-19 or influenza. (People who were admitted for another reason, such as a heart attack, and were then found to have a coronavirus infection weren’t included in the analysis.)

The COVID-19 patients were a little older, on average, than the flu patients (73.9 versus 70.2 years old), and they were less likely to be current or former smokers. They were also more likely to have received at least three doses of COVID-19 vaccine and less likely to have shunned the shots altogether.

Yet after Al-Aly and his colleagues accounted for these differences and a host of other factors, they found that 5.7% of the COVID-19 patients died of their disease, compared with 4.2% of the influenza patients.

In other words, the risk of death from COVID-19 was still 35% greater than it was for the flu. The findings were published Wednesday in the Journal of the American Medical Assn.

“There is undeniably an impression out there that [COVID-19] is no longer a major threat to human health,” Al-Aly said. “I think it’s largely driven by opinion and an emotional itch to move beyond the pandemic, to put it all behind us. We want to believe that it’s like the flu, and we did — until we saw the data.”

Dr. Peter Chin-Hong, an infectious diseases specialist at UC San Francisco, said the study results are right in line with what he sees in his hospital.

“COVID continues to make some people in our community very ill and die — even in 2024,” he said. “Although most will not get seriously ill from COVID, for some people it is like 2020 all over again.”

That’s particularly true for people who are older, who haven’t received their most recent recommended COVID-19 booster, and who haven’t taken full advantage of antivirals such as Paxlovid. Chin-Hong noted that only 5% of the COVID-19 patients in the study had been treated with antivirals before they were hospitalized.

Even if the mortality rates for the COVID-19 and flu patients had been equal, COVID-19 would still be the bigger health threat because it is sending more people to the hospital, Al-Aly said.

Between Oct. 1 and the end of March, 75.5 out of every 100,000 Americans had been hospitalized with influenza, according to the Centers for Disease Control and Prevention. During that same period, the hospitalization rate for COVID-19 was 122.9 per 100,000 Americans, the CDC says.

“COVID still carries a higher risk of hospitalization,” Al-Aly said. “And among those hospitalized, more will die as a result.”

Yet Al-Aly noted with frustration that while 48% of adults in the U.S. received a flu shot this year, only 21% of adults are up to date with their COVID-19 vaccinations, according to the CDC.

Chin-Hong added that more than 95% of adults hospitalized with COVID-19 this past fall and winter had not received the latest booster shot, according to the CDC.

Considering all the tools available to prevent hospitalizations and deaths — and especially the fact that they are readily available to patients in the VA system — the 35% relative risk of death from COVID-19 compared with the flu was “surprisingly high,” Chin-Hong said.

And it’s not like the flu is a trivial health threat, especially for senior citizens and people who are immunocompromised. It routinely kills tens of thousands of Americans each year, CDC data show.

“Influenza is a consequential infection,” Al-Aly said. “Even when COVID becomes equal to the flu, it’s still sobering and significant.”

The researchers also compared the mortality rates of VA COVID-19 patients before and after Dec. 24, when the Omicron subvariant known as JN.1 became the dominant strain in the United States. The difference was not statistically significant.

In just the last two weeks, JN.1 appears to have been overtaken by one of its descendants, a subvariant known as KP.2. It’s part of a family of subvariants that’s taken on the nickname “FLiRT,” a moniker that references some of the mutations that have cropped up on the viruses’ spike proteins.

So far, there’s no indication that KP.2 is any more dangerous than JN.1, Al-Aly said.

“Are the hospitals filling up? No,” he said. “Are ER rooms all over the country flooded with respiratory illness? No.” Nor are there worrying changes in the amount of coronavirus detected in wastewater.

“When you look at all these data streams, we’re not seeing ominous signs that KP.2 is something the general public should worry about,” Al-Aly said.

It’s also too early to tell whether KP.2 — or whatever comes after it — will finally erase the mortality gap between COVID-19 and the flu, he added.

“Maybe when we do a rematch in 2025, that will be the case,” he said.

There is a bird flu outbreak going on. Here is what you need to know about it:

What is bird flu?

Bird flu is what’s known as a highly pathogenic avian influenza virus. The “highly pathogenic” part refers to birds, which the virus is pretty adept at killing. In virology speak, the virus is of the Influenza A type, and is called H5N1. The “H” stands for the protein Hemagglutinin (HA), of which there are 16 subtypes (H1-H16). The “N” is short for Neuraminidase (NA), of which there are 9 subtypes (N1-N9). There are many possible combinations of HA and NA proteins. The two known type A human influenza viruses are H1N1 and H3N2. (Two additional subtypes, H17N10 and H18N11, have been identified in bats).

When did this bird flu first appear?

The current strain of H5N1 circulating the globe originated in 1996, in farmed geese living in China’s Guangdong province. It quickly spread to other poultry and migrating birds. By the early 2000s, it had spread across southern Asia. By 2005, it was observed in the Middle East, Africa and Europe. In 2014, it showed up in North America, but appeared to peter out here while it still raged in Europe, the Middle East and Africa. In 2021, it showed up in wild birds migrating off Canada’s Atlantic coast. Since then, it has spread across North and South America.

What kinds of animals does bird flu effect?

Birds are the primary carriers and victims of the virus. Across the globe, hundreds of millions of wild and domestic birds have died. Since 2021, hundreds of U.S. poultry farms have had to “depopulate” millions of birds after becoming infected, presumably from sick, migrating wild birds. The virus is highly contagious among birds and has a nearly 100% fatality rate. Mammals, too have been infected and died. In most cases, these are scavenging or predatory animals that ate sick birds — and the virus has died in these animals and not become contagious between them. So far, 48 species of mammals have become infected. However, there have been a few cases in which it appears the virus may have spread between mammals, including on European fur farms, on a few South American beaches where elephant seals came to roost, and now among dairy cattle in the United States.

Can humans get bird flu?

Since 2003, when the virus first started spreading through southern Asia, there have been 868 cases of human infection with H5N1 reported, of which 457 were fatal — a 53% case fatality rate. There have been only two cases in the U.S. In 2022, a poultry worker was infected in Colorado and suffered only mild symptoms, including fatigue. In 2024, a dairy worker was infected in Texas and complained only of conjunctivitis, or pink eye.

Why is everyone paying attention to dairy cows?

On March 25, 2024, officials announced that dairy cows in Texas had been infected with bird flu. Since then, the virus has been found in 36 herds across nine states. There are no known cases in California. It is believed that there was a single introduction of the virus from wild bird exposure (either by passive exposure, or maybe from eating contaminated feed), that probably occurred in December in Texas. The virus has since been detected in milk. A study conducted by federal researchers found that 1 in 5 milk samples collected from retail stores had the virus. It is believed that the virus may be passing between cows and that there may be cows that show no symptoms. For the most part, it seems dairy cows only suffer mild illness when infected, and milk production slows. They clear the virus after a few weeks.

Is it safe to drink milk?

Yes — if it is pasteurized milk. Federal officials say the virus they have detected in pasteurized milk samples is inactive and will not cause disease. In the case of raw milk, they urge people to avoid it. That’s because they have found high viral loads in raw milk samples. In addition, studies of barn cats that have consumed raw milk have reported severe consequences. In one cluster of 24 barn cats, half of them died after consuming raw milk, with others suffering blindness, neurological distress and copious nasal discharge. The virus has not been found in sour cream or cottage cheese.

What’s the situation with wastewater?

As health officials and researchers scramble to understand how widespread avian flu is in cattle and the environment, they are analyzing municipal wastewater. One team from Emory University and Stanford University looked at 190 wastewater treatment sites in 41 states. They found a surge of Influenza A virus in the last several weeks at 59 sites. This does not necessarily mean there is bird flu at these sites. However, in places where the team has gone to investigate — including three in Texas where they knew there was H5N1 in dairy cattle — they have found bird flu. Influenza A is generally seasonal in humans — peaking from late fall to early spring. The surge the researchers noticed — including at several sites in California — started after the flu season had died down. Researchers in Texas have also detected H5N1 in the wastewater of nine of 10 cities they tested, all located in Texas. The CDC is also monitoring for Influenza A at roughly 600 sites across the nation.

Kori Thompson had long wrestled with the idea of having a child.

The 24-year-old worried about the world a kid would face as climate change overtook the globe, fearing the environmental devastation and economic strain that could follow. He had been thinking about getting a vasectomy ever since he learned about the sterilization procedure from a television show.

But “the thing that actually triggered it was the court decision,” Thompson said.

After the Supreme Court overturned Roe vs. Wade nearly two years ago, paving the way for states to usher in new restrictions on abortion, doctors started seeing more young adults seeking vasectomies or getting their tubes tied, emerging research has found.

An analysis by University of Utah researchers, released as an abstract in the Journal of Urology, found that after Dobbs vs. Jackson Women’s Health Organization, a rising share of vasectomy patients were under the age of 30.

That percentage went from 6.2% to 9.8% after the Supreme Court decision, based on their analysis of a national database that includes hundreds of millions of patients.

Among the young patients who pursued the procedure is Thompson, who decided to get a vasectomy in the aftermath of the court ruling. In Georgia where he lives, abortion is illegal roughly six weeks into a pregnancy — a point before some people may learn that they are pregnant.

“If it’s effectively illegal,” Thompson said, “then I felt that this was necessary.” His girlfriend also disliked the effects of hormonal birth control, “so now I’ve decided to go on permanent birth control. It’s way easier.”

The University of Utah researchers found that before the Supreme Court ruling, vasectomy rates were consistently higher in states categorized as “hostile” or “illegal” for abortion by the Center for Reproductive Rights, compared to states that were not as restrictive. The same was true after the ruling.

Yet researchers also found an overall uptick in vasectomy rates after the Dobbs decision — both in states where abortion is heavily restricted and those where it is not.

In California, where state leaders have vowed to protect abortion rights, the rate of men getting vasectomies rose after the court decision, from roughly 7 to 13 per 100,000 potential patients, the Utah team found.

“We’re just seeing an overall increase in vasectomies — regardless of political climate” in each state, said Dr. Jessica Schardein, a urologist at the University of Utah. Schardein said the Supreme Court ruling and increased marketing for vasectomies may have gotten more people thinking about the procedure.

“People in general, even if they don’t have a uterus, are taking responsibility for their reproductive health,” Schardein said.

Her team also examined tubal sterilizations — a medical procedure often called “getting your tubes tied,” performed on the fallopian tubes connected to the uterus — and found that after the court decision, there was an increase in the percentage of patients ages 18 to 30 among those undergoing the procedure.

In Riverside County, Jacob Snow decided to get a vasectomy after the birth of his third child, concluding it was a safer option than his wife had for sterilization. “There’s no reason why all the blame and stress and trying to stop a pregnancy should be placed on the female when I can stop it at my end,” the 28-year-old said.

Even though Snow was already a parent, the doctor balked because of his age, he said. “They said I might change my mind in the future,” Snow recalled. “They flat out just refused.”

Vasectomies are intended to be permanent. The surgery may be able to be reversed with other procedures, but physicians caution that doing so is not a guaranteed option.

Snow ultimately found another doctor to do the procedure. Besides the pushback from the first physician, Snow said some men have been aghast when he tells them he had a vasectomy, saying it would make them feel like less of a man. But Snow said he doesn’t “feel that reproducing is how I need to prove that I’m a man.”

The University of Utah findings, presented at the annual meeting of the American Urological Assn., have been echoed in other recent research.

Last month, researchers from the University of Pittsburgh School of Public Health and Boston University published findings in JAMA Health Forum showing “an abrupt increase” in vasectomies and tube tying following Dobbs, with a sharper increase in tubal ligation.

The difference “likely reflects the fact that young women are overwhelmingly responsible for preventing pregnancy and disproportionately experience the health, social and economic consequences of abortion bans,” University of Pittsburgh assistant professor Jacqueline Ellison said in a statement.

Another analysis in the Journal of Urology that included multiple medical centers around the country — including UCLA — found that after the Dobbs decision, the typical patient seeking a vasectomy was younger than before. Researchers also found that an increased share were childless.

There was also a rise in the number of patients consulting doctors about the medical procedure, said Dr. Kara Watts, a urologist at Montefiore Medical Center in New York City — and longer waits to get the surgery after a consultation. If wait times weren’t an issue, Watts said, “the numbers would probably be even more dramatic.”

Researchers detected a similar trend in the UC San Diego health system, where there was a rise in men seeking consultations about vasectomies after the Dobbs decision, as well as increased rates of patients going through with the procedure after their consultations, according to another review presented at the urology meeting.

Even though California has enshrined abortion rights in its state constitution, “I think that vasectomy consultations and completion rates still increased due to the national media coverage on the Supreme Court ruling,” said Dr. Vi Nguyen, one of the authors of the analysis.

And at Ohio State University, urologists surveyed patients about why they chose to get vasectomies and found that after the Dobbs decision, they were more likely to cite concerns about abortion access or say that “they did not want to bring children into the current political climate.”

Other reasons for wanting a vasectomy, such as health concerns, did not change after Dobbs, the survey found. Dr. Jessica Yih, an assistant professor of urology at the Ohio State University, wasn’t surprised.

“Immediately after the Dobbs ruling, many people were extremely concerned about their reproductive rights,” Yih said in an email. “We had a threefold increase in referrals of patients who were wanting to be scheduled to discuss vasectomies and the number of vasectomies performed around this time increased dramatically.”

Abortion has been a sharply contested issue in Ohio, where a law banning abortion after six weeks of pregnancy initially went into effect after the Dobbs ruling. That ban was later put on hold in court, and Ohio voters have since backed protections for abortion access in its state constitution.

“Many patients told us at our clinics that they wanted their vasectomies done as soon as possible due to concerns about restrictions in abortion access,” Yih said.