There’s a good chance you’ve seen headlines about HMPV recently, with some touting “what you need to know” about the virus, aka human metapneumovirus. The answer is: not much.
It’s a common, usually mild respiratory virus that circulates every year, blending into the throng of other seasonal respiratory illnesses that are often indistinguishable from one another. (The pack includes influenza virus, respiratory syncytial virus (RSV), adenovirus, parainfluenza virus, common human coronaviruses, bocavirus, rhinovirus, enteroviruses, and Mycoplasma pneumoniae, among others.) HMPV is in the same family of viruses as RSV.
As one viral disease epidemiologist at the US Centers for Disease Control summarized in 2016, it’s usually “clinically indistinguishable” from other bog-standard respiratory illnesses, like seasonal flu, that cause cough, fever, and nasal congestion. For most, the infection is crummy but not worth a visit to a doctor. As such, testing for it is limited. But, like other common respiratory infections, it can be dangerous for children under age 5, older adults, and those with compromised immune systems. It was first identified in 2001, but it has likely been circulating since at least 1958.
The situation in China
The explosion of interest in HMPV comes after reports of a spike of HMPV infections in China, which allegedly led to hordes of masked patients filling hospitals. But none of that appears to be accurate. While HMPV infections have risen, the increase is not unusual for the respiratory illness season. Further, HMPV is not the leading cause of respiratory illnesses in China right now; the leading cause is seasonal flu. And the surge in seasonal flu is also within the usual levels seen at this time of year in China.
Last week, the Chinese Center for Disease Control and Prevention released its sentinel respiratory illness surveillance data collected in the last week of December. It included the test results of respiratory samples taken from outpatients. Of those, 30 percent were positive for flu (the largest share), a jump of about 6 percent from the previous week (the largest jump). Only 6 percent were positive for HMPV, which was about the same detection rate as in the previous week (there was a 0.1 percent increase).
Slivered onions are the likely source of the multi-state E. coli outbreak linked to McDonald’s Quarter Pounder burgers that continues to grow, the Centers for Disease Control and Prevention announced Wednesday.
Onions were one of two primary suspects when the CDC announced the outbreak on October 22, with the other being the beef patties used on the burgers. But onions quickly became the leading suspect. The day after the CDC’s announcement, McDonald’s onion supplier, Taylor Farms, recalled peeled and diced yellow onion products and several other fast food chains took onions off the menu as a precaution. (No other restaurants have been linked to the outbreak to date.)
According to the CDC, traceback information and epidemiological data collected since then have all pointed to the onions and, according to McDonald’s, state and federal testing of the beef patties has all come back negative.
In the CDC’s update Wednesday, the agency reported that 15 more people were identified as sickened in the outbreak, including five who were hospitalized. In all, that brings the outbreak to 90 cases, including 27 hospitalizations and one death, which collectively span 13 states.
All the newly reported illnesses had onsets prior to the October 23 onion recall. The most recent illness onset was October 16. Additional illnesses may be reported, as it can take three to four weeks to link illnesses to an outbreak.
“Due to the product actions taken by McDonald’s and Taylor Farms, the CDC believes the continued risk to the public is very low,” the agency said in a media alert.
McDonald’s says that Quarter Pounders—without onions—will return to the menus of affected restaurants this week. Prior to the recall, 900 restaurants had received onions from Taylor Farms, including in Colorado, Kansas, and Wyoming, as well as portions of Idaho, Iowa, Missouri, Montana, Nebraska, Nevada, New Mexico, Oklahoma, and Utah.
The 26 new cases represent a 50 percent increase in the case count from October 22, bringing the total to 75 cases. With the new cases, health officials also reported 12 more hospitalizations, including one new adult case of hemolytic uremic syndrome (HUS), a severe complication to an E. coli O157:H7 infection. Three more states are also newly affected: Michigan, New Mexico, and Washington.
In all, the outbreak now stands at 75 cases, including 22 hospitalizations and two cases of HUS, across 13 states. The number of deaths linked to the outbreak remains at one. The most recent illness onset for the cases identified so far is October 10.
The states with cases now include: Colorado (26 cases), Montana (13), Nebraska (11), New Mexico (5), Utah (5), Missouri (4), Wyoming (4), and Michigan (2), and one case each in Iowa, Kansas, Oregon, Washington, and Wisconsin.
The source of the outbreak has not yet been confirmed, but investigators have focused on the beef patties and slivered onions used on McDonald’s Quarter Pounders. McDonald’s immediately pulled the popular burger off the menu and paused distribution of the slivered onions from affected restaurants when the CDC announced the outbreak Tuesday. McDonald’s considered the affected areas to be Colorado, Kansas, Utah, and Wyoming, as well as portions of Idaho, Iowa, Missouri, Montana, Nebraska, Nevada, New Mexico, and Oklahoma.
Onions recalled and destroyed
On Wednesday, one of McDonald’s onion suppliers, Taylor Farms, recalled peeled and diced yellow onion products. Taylor Farms told Bloomberg earlier this week that its testing had not turned up E. coli, but that it decided to issue the recall anyway.
If you’re going to eat a bear, make sure it’s not rare.
You’d be forgiven for thinking that once the beast has been subdued, all danger has passed. But you might still be in for a scare. The animal’s flesh can be riddled with encased worm larvae, which, upon being eaten, will gladly reproduce in your innards and let their offspring roam the rest of your person, including invading your brain and heart. To defeat these savage squirmers, all one must do is cook the meat to at least 165° Fahrenheit.
But that simple solution continues to be ignored, according to a report today in the Centers for Disease Control and Prevention’s Morbidity and Mortality Weekly Report. In this week’s issue, health officials in North Carolina report that rare bear meat was served at a November 23 gathering, where at least 22 people ate the meat and at least 10 developed symptoms of a worm infection. Of the 10, six were kids and teens between the ages of 10 and 18.
The infection is from the roundworm Trichinella, which causes trichinellosis. While the infection is rarely fatal, the nematodes tend to burrow out of the bowels and meander through the body, embedding in whatever muscle tissue they come across. A telltale sign of an infection in people is facial swelling, caused when the larvae take harbor in the muscles of the face and around the eyes. Of the 10 ill people in North Carolina, nine had facial swelling.
Local health officials were onto the outbreak when one person developed flu-like symptoms and puzzling facial swelling. They then traced it back to the gathering. The report doesn’t specify what kind of gathering it was but noted that 34 attendees in total were surveyed, from which they found the 22 people who ate the rare meat. The 10 people found with symptoms are technically considered only “probable” cases because the infections were never diagnostically confirmed. To confirm a trichinellosis infection, researchers need blood samples taken after the person recovers to look for antibodies against the parasite. None of the 10 people returned for blood draws.
If you were looking for a reason to keep a flamethrower around the house, you may have just found one.
This week, the Los Angeles County health department reported that two people were infected with a raccoon parasite that causes severe, frequently fatal, infections of the eyes, organs, and central nervous system. Those who survive are often left with severe neurological outcomes, including blindness, paralysis, loss of coordination, seizures, cognitive impairments, and brain atrophy.
The parasitic roundworm behind the infection, called Baylisascaris procyonis, spreads via eggs in raccoons feces. Adult worms live in the intestines of the masked trash scavengers, and each female worm can produce nearly 200,000 eggs per day. Once in the environment, those eggs can remain infectious for years. They can survive drying out as well as most chemical treatments and disinfectants, including bleach.
Humans get infected if they inadvertently eat soil or other material that has become contaminated with egg-laden feces. Though infections are rare—there were 29 documented cases between 1973 and 2015—younger children and people with developmental disabilities are most at risk.
For instance, an 18-month-old boy with Downs syndrome in Illinois died from the infection after he chewed and sucked on pieces of contaminated firewood bark. An autopsy later found three worm larvae per gram of his brain tissue, with a total estimated burden of 3,027 parasitic larvae, according to a 2016 report.
Burn it down
In a news release this week, the LA health department said the risk to the general public is “low” but that the two cases are “concerning because a large number of raccoons live near people, and the infection rate in raccoons is likely high. The confirmed cases of this rare infection are an important reminder for all Los Angeles County residents to take precautions to prevent the spread of disease from animals to people, also known as zoonotic disease.”
According to the Centers for Disease Control and Prevention, one of the best prevention methods for raccoon roundworms is to kill it with fire. While chemicals stand little chance of killing off infectious eggs, extreme heat destroys them instantly.
If you have raccoons around your property, you might need to employ this method. Raccoons tend to poop in communal, pungent latrines, which are often at the base of trees, on raised surfaces—such as tree stumps, woodpiles, decks, and patios—as well as in attics and garages.
If you suspect you have an outdoor raccoon latrine on your property, the CDC recommends dousing the area in boiling water or setting it ablaze. While the CDC recommends a propane torch, specifically, a personal flamethrower could also do the trick. The agency does caution that flaming a latrine site “could cause a fire, burn injury, or surface damage.”
“Before flaming any latrine site, call your local fire department for details on local regulations and safety practices,” the CDC says. “Concrete pads, bricks, and metal shovels or garden implements can be flamed without damage. Do not attempt to flame surfaces that can melt or catch fire.”
For indoor latrines, the CDC advises not to use fire. Instead, it outlines a cautious cleaning method with hot, soapy water. However, if you want, any removed feces or contaminated material can be flamed outside, if not buried or put in the trash.
Enlarge/ Herpes simplex virus, (HSV). Image taken with transmission electron microscopy.
As the US Surgeon General recently highlighted, parenting is stressful. From navigating social media to facing a youth mental health crisis, challenges abound. But, for one father in Spain, even the simple, loving, everyday act of giving your child a peck on the cheek has turned to nightmare fuel.
According to a case report in the New England Journal of Medicine, the man’s 9-year-old daughter developed a fever along with a crusty, blistering lesion on her left cheek. Doctors initially diagnosed the blotch as impetigo, a bacterial infection on the skin’s surface layers that is fairly common in children. It’s often caused by Staphylococcus aureus or Streptococcus bacteria and is generally easily treated with antibiotics.
Enlarge/ The lesion on the girl’s cheek with satellite blisters noted by arrows.
But, after several days of treatment for impetigo, the child’s symptoms weren’t getting better. At that point, it had been seven days since the lesion erupted, and it was 3 centimeters in diameter on the side of her face. So, he took her to a dermatology clinic. There, specialists closely examined the lesion, noting the red, raised area with blisters and a “honey-crusted appearance,” which is a classic sign of impetigo. They also noted smaller “satellite” blisters around the cheek, as well as swollen lymph nodes on the left side of her neck, the same side as the lesion. All of the symptoms still lined up with impetigo. But then the specialists looked over at her dad.
The doctors took note of a crusting on her father’s lower lip, which he said had started 10 days earlier. It looked like a classic case of common cold sores, aka oral herpes. And the doctors made a connection.
Stress begets stress
Cold sores are caused by herpes simplex virus type 1 (HSV-1), a highly contagious virus that is estimated to infect 3.7 billion people under the age of 50 globally. (There’s also HSV-2, which causes genital herpes). In an initial infection, herpes viruses invade cells on the body’s surfaces, but then go into hiding in nerve cells. From there, they can occasionally reactivate and produce new lesions and infections. For HSV-1, that usually means cold sores around the mouth.
There is no cure for herpes infections; the virus will lurk in a person’s nerve cells for the rest of their lives, with the potential to spur recurring outbreaks. However, there are antiviral treatments that can ease the symptoms of outbreaks and help them clear up a little faster.
When a cold sore develops, the lesions are highly infectious. It’s often transmitted through oral-oral contact, but any direct contact or contact with contaminated saliva can spread the virus. (HSV-2 primarily spreads through sexual contact.) And, while HSV-1 lesions typically erupt around the mouth and on mucosal surfaces, they can sometimes also flare elsewhere on the skin.
The dermatologists treating the 9-year-old ran a test for HSV-1, confirming the genetic traces of the virus were present. They started the girl on an oral antiviral drug. They also noted that there was no concern for sexual abuse. The lesion cleared without scarring.
In their report on the case, they end with a note of caution for other doctors: “When HSV-1 infection manifests in children as cutaneous lesions without mucosal involvement, it may be confused with the honey-crusted appearance of impetigo.”
For parents, the lesson is to be careful not to kiss your child (or anyone else) when you have a cold sore flare up. While those viral reactivations can be sparked by many things, one notable factor will likely strike home for parents: stress.
who refused to isolate and get treatment for her active case of infectious tuberculosis for over a year. She even spent around three months on the lam, dodging police as they tried to execute a civil arrest warrant. During her time as a fugitive, police memorably reported that she took a city bus to go to a casino.
The woman, identified only as V.N. in court documents, had court orders to get treatment for her tuberculosis infection beginning in January of 2022. She refused to comply as the court renewed the orders on a monthly basis and held at least 17 hearings on the matter. The judge in her case issued an arrest warrant in March of 2023, but V.N. evaded law enforcement. She was finally arrested in June of last year and spent 23 days getting court-ordered treatment behind bars before being released with conditions.
This week, James Miller, a health officer for Washington’s Tacoma-Pierce County, where V.N. resides, announced the happy ending.
“The woman cooperated with Pierce County Superior Court’s orders and our disease investigators. She’s tested negative for tuberculosis (also called TB) multiple times. She gained back weight she’d lost and is healthy again,” Miller reported. He noted that V.N. and her family gave the county permission to share the news and said they are now happy she received the treatment she needed.
Amid the legal attempts to get V.N. treated, the health department noted in court documents that V.N. had been in a car accident in January 2023, after which she had gone to an emergency department complaining of chest pain. Doctors there—who did not know she had an active case of tuberculosis—took X-rays of her lungs. The images revealed that her lungs were in such bad shape that the doctors thought she had cancer. In fact, the images revealed that her tuberculosis case was worsening.
Risky infection
Tuberculosis is a potentially life-threatening bacterial infection caused by Mycobacterium tuberculosis, which mostly infects the lungs but can invade other areas of the body as well. The bacteria spread through the air when an infected person coughs, sneezes, spits, or otherwise launches bacterial cells into the air around them. Although transmission mostly occurs from close, prolonged contact, inhaling only a few of the microscopic germs is enough to spark an infection. According to the World Health Organization, tuberculosis killed 1.3 million people in 2022 and infected an estimated 10.6 million. Worldwide, it was the second leading infectious killer after COVID-19 that year.
Treatment for tuberculosis requires lengthy antibiotic regimens, which are typically taken for four to nine months. Drug-resistant infections require second-line, more toxic drugs. In the past, treatment for multi-drug resistant tuberculosis could last up to 20 months, but newer clinical guidances prioritize shorter regimens.
Given the risks to herself and those around her, county health officials did all they could to get V.N. treated. “Seeking a court order is our last resort after we exhaust all other options,” Miller said. “It’s a difficult process that takes a lot of time and coordination with other agencies.”
But according to Miller, V.N. softened to the idea of being treated once she was in custody and county disease investigators worked to gain her trust. “At that point, she realized how serious her situation was and decided to treat her illness,” he said. With treatment, she “regained her health over time.”
“She is now cured, which means that tuberculosis no longer poses a risk to her health,” he concluded. “This also means she is no longer at risk of infecting others.”
The highly pathogenic avian influenza H5N1 virus that spilled from wild birds into US dairy cows late last year may have recently seeped from a dairy farm in Colorado to a nearby poultry farm, where it then infected five workers tasked with culling the infected chickens
In a press briefing Tuesday, federal officials reported that four of the avian influenza cases have been confirmed by the Centers for Disease Control and Prevention, while the fifth remains a presumptive positive awaiting CDC confirmation.
All five people have shown mild illnesses, though they experienced variable symptoms. Some of the cases involved conjunctivitis, as was seen in other human cases linked to the H5N1 outbreak in dairy cows. Others in the cluster of five had respiratory and typical flu-like symptoms, including fever, chills, sore throat, runny nose, and cough. None of the five cases required hospitalization.
The virus infecting the five people is closely related to the virus infecting the chickens on the poultry farm, which, in turn, is closely related to virus seen in infected dairy herds and in other human cases that have been linked to the dairy outbreak. The affected poultry farm is in Colorado’s northern county of Weld, which has also reported about two dozen outbreaks of avian influenza in dairy herds.
Dairy to poultry hypothesis
In one fell swoop, Colorado’s poultry farm outbreak has more than doubled the number of human avian influenza cases linked to the dairy cow spillover, bringing the previous tally of four cases to nine. While officials have previously noted instances where it appeared that H5N1 on dairy farms had moved to nearby poultry farms, this appears to be the first time such spread has led to documented human infections.
The link between the poultry farm cases and neighboring dairy farms is still just a hypothesis, however, Nirav Shah, the principal deputy director at the CDC, emphasized to reporters Tuesday. “It is a hypothesis that needs and requires a full investigation. But that is a hypothesis at this point,” he said of the link between the dairy farms and the poultry farm. So far, there is no direct evidence of a specific source of the poultry farm’s infection, and the route of infection is also unclear.
Throughout the outbreak of H5N1 on dairy farms, officials have noted that the primary way the virus appears to spread to new farms is via the movement of cows, people, and machinery between those facilities. There remains no evidence of human-to-human transmission. But milk from infected cows has been found to be brimming with high levels of infectious virus, and milk-contaminated equipment is a prime suspect in the spread.
In the press briefing Tuesday, Eric Deeble, acting senior advisor for H5N1 response with the US Department of Agriculture, noted the poultry are very susceptible to avian influenza and are easily infected. “It does not take much to introduce this into a flock,” Deeble said. The USDA is now working on a “trace-back” investigation on how the Colorado poultry farm was infected.
Searing spread
As for how the farm workers specifically became infected with the virus, health officials pointed to high temperatures that prevented workers from donning protective gear. The poultry farm is a commercial egg layer operation with around 1.8 million birds. Given the presence of bird flu on the premises, all 1.8 million birds need to be culled, aka “depopulated.” This is being carried out using mobile carts with carbon dioxide gas chambers, a common culling method. Workers are tasked with placing the birds in the chambers, which only hold a few dozen birds at a time. In all, the method requires workers to have a high degree of contact with the infected birds, going from bird to bird and batch to batch with the carts.
Amid this grim task, temperatures in the area reached over 100° Fahrenheit, and massive industrial fans were turned on in the facility to try to cool things down. Between the heat and the fans, the approximately 160 people involved in the culling struggled to use personal protective equipment (PPE). The required PPE for the depopulation involves a full Tyvek suit, boots, gloves, goggles, and an N95 respirator.
“The difficulty with wearing all that gear in that kind of heat, you can imagine,” said Julie Gauthier, executive director for field operations at the USDA’s Animal and Plant Health Inspection Service (APHIS). The industrial fans blowing large amounts of air made it yet more difficult for workers to keep goggles and respirators on their faces, she said.
The CDC and the USDA are both involved in further investigations of the poultry farm outbreak. CDC’s Shah noted that the team the agency deployed to Colorado included an industrial hygienist, who can work on strategies to prevent further transmission.
To date, at least 161 herds in 13 states have tested positive for avian influenza since the dairy outbreak was confirmed in March. Since January 2022, when US birds first tested positive for the H5N1 virus, 99 million birds in the US have been affected in 48 states, which involved 1,165 individual outbreaks.
Enlarge/ A dog gets examined by veterinary technicians in Texas.
Two separately owned dogs in New Jersey tested positive last year for a dreaded, extensively drug resistant bacterial strain spread in the US by contaminated artificial eye drops manufactured in India. Those drops caused a deadly multi-state outbreak in humans over many months last year, with at least 81 people ultimately infected across 18 states. Fourteen people lost their vision, an additional four had eyeballs surgically removed, and four people died.
The preliminary data on the dogs—presented recently at a conference of disease detectives hosted by the Centers for Disease Control and Prevention—highlights that now that the deadly outbreak strain has been introduced around the US, it has the potential to lurk in unexpected places, spread its drug resistance to fellow bacteria, and cause new infections in people and animals who may have never used the drops.
The two dogs in New Jersey were not known to have received the drops linked to the outbreak: EzriCare Artificial Tears and two additional products made by the same manufacturer, which were recalled in February 2023. Such over-the-counter products are sometimes used in animals as well as people. But the dogs’ separate owners said they didn’t recall using the drops either. They also didn’t report any exposures in health care settings or recent international travel that could explain the infections. One of the dogs did, at one point, receive eye drops, but they were not an outbreak-associated brand. The only connection between the two dogs was that they were both treated at the same veterinary hospital, which didn’t stock the outbreak-associated eyedrops.
The dogs’ infections were caught between March and June 2023 when clinicians at the veterinary hospital were working to address a chronic cough in one of the dogs and a stubborn ear infection in the other, according to CBS News, which was present for the CDC’s conference of its Epidemic Intelligence Service in Atlanta. The ear and lung swabs were sent to an academic veterinary laboratory in Pennsylvania, where a microbiologist noticed that bacteria from both swabs had uncommon drug-resistance features. The microbiologist then uploaded genetic sequences of the bacterial strains to a national database, where they caught the attention of the CDC and state health authorities.
The genetic sequences uploaded were of the carbapenemase-producing carbapenem-resistant Pseudomonas aeruginosa (CP-CRPA) strain—and they were highly similar to the bacterial strain identified in the deadly eyedrop outbreak. These bacteria are extensively resistant to antibiotics, resisting even last-line drugs, and can silently colonize animals and humans for months or years. An investigation ensued.
Infection gaps
Emma Price, the CDC epidemic intelligence service officer who presented the investigation’s findings at the conference, suggested it was fortunate they were able to make the connection. “Because [the academic veterinary laboratory] had a grant and a veterinary microbiologist works there, he did his great due diligence and uploaded the results. That’s how we got the notification, because the strain matched the outbreak strain,” Price told CBS News.
However, the disease detectives were ultimately unable to identify exactly how the two dogs became infected. “Shared exposures included treatment in the veterinary hospital’s surgical preparation and recovery areas for both canines and ophthalmology department visits by either the affected canine or another animal in the same household,” Price and colleagues wrote in their findings. But all of the sampling done of the veterinary hospital where the dogs were treated turned up negative for the eyedrop outbreak strain.
In the process of the investigation, the epidemiologists also conducted an infection control assessment of the veterinary hospital, finding a variety of “gaps.” These included problems with hand hygiene practices, personal protective equipment use—including use of gloves—and equipment and environmental cleaning and disinfection at the hospital. Price noted that these problems are not uncommon and that there is a general lack of emphasis on infection control in veterinary settings.
Though Price and her colleagues were unable to identify the direct route of infection, they suspect the dogs were likely infected either by exposure to a contaminated product or secondary transmission at the veterinary hospital.
Both dogs have since made full recoveries, but because CRPA strains can silently colonize many body sites on both humans and animals, it’s possible that the bacteria still linger on the dogs or on the other pets and people in their households. Price warned the owners of possible future transmission and recommended they flag this risk to their health care providers. She also noted the potential for the bacteria to spread from dog to dog. It would be ideal to “keep the dogs away from other dogs in the future, which we understand is a difficult thing to do,” she said.
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.
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.
Enlarge/ A view from a hospital as children receiving medical treatment, in capital Kabul, Afghanistan on April 18, 2022. More than 130 children have died from the measles in Afghanistan since the beginning of this year.
The Centers for Disease Control and Prevention and the American Medical Association sent out separate but similar pleas on Monday for unvaccinated Americans to get vaccinated against the extremely contagious measles virus as vaccination rates have slipped, cases are rising globally and nationally, and the spring-break travel period is beginning.
In the first 12 weeks of 2024, US measles cases have already matched and likely exceeded the case total for all of 2023. According to the CDC, there were 58 measles cases reported from 17 states as of March 14. But media tallies indicate there have been more cases since then, with at least 60 cases now in total, according to CBS News. In 2023, there were 58 cases in 20 states.
“As evident from the confirmed measles cases reported in 17 states so far this year, when individuals are not immunized as a matter of personal preference or misinformation, they put themselves and others at risk of disease—including children too young to be vaccinated, cancer patients, and other immunocompromised people,” AMA President Jesse Ehrenfeld said in a statement urging vaccination Monday.
The latest data indicates that vaccination rates among US kindergarteners have slipped to 93 percent nationally, below the 95 percent target to prevent the spread of the disease. And vaccine exemptions for non-medical reasons have reached an all-time high.
The CDC released a health advisory on Monday also urging measles vaccination. The CDC drove home the point that unvaccinated Americans are largely responsible for importing the virus, and pockets of unvaccinated children in local communities spread it once it’s here. The 58 measles infections that have been reported to the agency so far include cases from seven outbreaks in seven states. Most of the cases are in vaccine-eligible children aged 12 months and older who are unvaccinated. Of the 58 cases, 54 (93 percent) are linked to international travel, and most measles importations are by unvaccinated US residents who travel abroad and bring measles home with them, the CDC flagged.
The situation is likely to worsen as Americans begin spring travel, the CDC suggested. “Many countries, including travel destinations such as Austria, the Philippines, Romania, and the United Kingdom, are experiencing measles outbreaks,” the CDC said. “To prevent measles infection and reduce the risk of community transmission from importation, all US residents traveling internationally, regardless of destination, should be current on their [measles-mumps-rubella (MMR)] vaccinations.” The agency added in a recommendation to parents that “even if not traveling, ensure that children receive all recommended doses of MMR vaccine. Two doses of MMR vaccine provide better protection (97 percent) against measles than one dose (93 percent). Getting MMR vaccine is much safer than getting measles, mumps, or rubella.”
For Americans who are already vaccinated and communities with high vaccination coverage, the risk is low, the CDC noted. “However, pockets of low coverage leave some communities at higher risk for outbreaks.” This, in turn, threatens wider, continuous spread that could overturn the country’s status of having eliminated measles, which was declared in 2000. The US was close to losing its elimination status in 2019 when outbreaks among unvaccinated children drove 1,247 cases across 31 states. Vaccination rates have only fallen since then.
“The reduction in measles vaccination threatens to erase many years of progress as this previously eliminated vaccine-preventable disease returns,” the AMA’s Ehrenfeld warned.
As Ars has reported previously, measles is among the most contagious viruses known and can linger in airspace for up to two hours. Up to 90 percent of unvaccinated people exposed will contract it. Symptoms can include high fever, runny nose, red and watery eyes, and a cough, as well as the hallmark rash. About 1 in 5 unvaccinated people with measles are hospitalized, while 1 in 20 infected children develop pneumonia, and up to 3 in 1,000 children die of the infection. Brain swelling (encephalitis) can occur in 1 in 1,000 children, which can lead to hearing loss and intellectual disabilities. The virus can also destroy immune responses to previous infections—a phenomenon known as “immune amnesia”—which can leave children vulnerable to various other infections for years afterward.
An Oregon resident contracted bubonic plague from their “very sick” pet cat, marking the first time since 2015 that someone in the state has been stricken with the Black Death bacterium, according to local health officials.
Plague bacteria, Yersinia pestis, circulates cryptically in the US in various types of rodents and their fleas. It causes an average of seven human cases a year, with a range of 1 to 17, according to the Centers for Disease Control and Prevention. The cases tend to cluster in two regions, the CDC notes: a hotspot that spans northern New Mexico, northern Arizona, and southern Colorado, and another region spanning California, far western Nevada, and southern Oregon.
The new case in Oregon occurred in the central county of Deschutes. It was fortunately caught early before the infection developed into a more severe, systemic bloodstream infection (septicemic plague). However, according to a local official who spoke with NBC News, some doctors felt the person had developed a cough while being treated at the hospital. This could indicate progression toward pneumonic plague, a more life-threatening and more readily contagious variety of the plague that spreads via respiratory droplets. Nevertheless, the person’s case reportedly responded well to antibiotic treatment, and the person is recovering.
Health officials worked to prevent the spread of the disease. “All close contacts of the resident and their pet have been contacted and provided medication to prevent illness,” Richard Fawcett, Deschutes County Health Officer, said in a news release.
Fawcett told NBC News that the cat was “very sick” and had a draining abscess, indicating “a fairly substantial” infection. The person could have become infected by plague-infected fleas from the cat or by handling the sick cat or its bodily fluids directly. Symptoms usually develop two to eight days after exposure, when the infection occurs in the lymph nodes. Early symptoms include sudden onset of fever, nausea, weakness, chills, muscle aches, and/or visibly swollen lymph nodes called buboes. If left untreated, the infection progresses to the septicemic or pneumonic forms.
It’s unclear how or why the cat became infected. But cats are particularly susceptible to plague and are considered a common source of infection in the US. The animals, when left to roam outdoors, can pick up infections from fleas as well as killing and eating infected rodents. Though dogs can also pick up the infection from fleas or other animals, they are less likely to develop clinical illness, according to the CDC.
While plague cases are generally rare in the US, Deschutes County Health Services offered general tips to keep from contracting the deadly bacteria, namely: Avoid contact with fleas and rodents, particularly sick, injured, or dead ones; Keep pets on a leash and protected with flea control products; Work to keep rodents out and away from homes and other buildings; and avoid areas with lots of rodents while camping and hiking and wear insect repellant when outdoors to ward off fleas.
According to the CDC, there were 496 plague cases in the US between 1970 and 2020. And between 2000 and 2020, the CDC counted 14 deaths.
