A federal vaccine advisory panel, newly reconstituted by U.S. Health Secretary Robert F. Kennedy Jr., has voted against thimerosal, a preservative long used in multi-dose flu vaccines, for use in all age groups. The recommendation, made by a unanimous vote, has caused shock waves in the medical and scientific communities, generating debate on vaccine safety, public confidence, and potential future availability of flu vaccines. The move revisits a debate many experts considered settled and could reshape how influenza vaccines are produced and distributed worldwide.

The newly restructured vaccine panel led by U.S. Health Secretary Robert F. Kennedy Jr. voted to advise against the use of thimerosal in flu shots given annually to millions of Americans. The move, taken by the Advisory Committee for Immunization Practices (ACIP), has raised alarm among scientists and public health professionals concerned the ruling could erode confidence in vaccinations and create disruptions in vaccine supplies, particularly during flu season.

In a 5-1 vote, with one abstention, ACIP members voted to limit thimerosal in all age groups for seasonal flu vaccines. The revamped panel, reorganized by Kennedy after she had all 17 of the agency's previous members dismissed over charges of conflict of interest, now includes appointees sympathetic to Kennedy's long-time vaccine skepticism.

"The threat from influenza is so much larger than the non-existent — to our knowledge, at least — threat from thimerosal," said Dr. Cody Meissner, professor of pediatrics at Dartmouth's Geisel School of Medicine and the lone dissenter. "I would be sorry if an individual did not get the influenza vaccine because the only product available contains thimerosal."

The Advisory Committee on Immunization Practices (ACIP), which advises the Centers for Disease Control and Prevention (CDC) on vaccine policy, is now in the middle of a storm. In June, Kennedy replaced all 17 of the former members, citing conflicts of interest, and appointed eight new members, many of whom are like-minded skeptics of vaccine safety. Five voted for, one voted against, and one abstained to limit thimerosal in flu vaccines.

What is Thimerosal?

Thimerosal is an ethylmercury-containing preservative that was first used in the 1930s to stop bacterial contamination of multi-dose vaccine vials. The compound in thimerosal, ethylmercury, is different from methylmercury—the form present in seafood—which is stored in the body and carries known health dangers. Ethylmercury, however, is metabolized and eliminated much faster.

The dose of ethylmercury from a standard dose of flu vaccine (25 micrograms) is about half that in a 3-ounce serving of canned tuna (40 micrograms) Thimerosal has been eliminated from almost all routine pediatric and most adult vaccines in the U.S. since the early 2000s as a precaution, even though there was no evidence to implicate it in harm. Now it still appears in only around 5% of multi-dose vials of flu vaccine.

Why Is Thimerosal Controversial?

Thimerosal became controversial in the late 1990s because it contains mercury and was theorized to cause autism and other neurodevelopmental disorders. Despite repeated, large-scale studies conducted in many countries, numerous studies have determined that there is no connection between thimerosal and neurological injury. The Centers for Disease Control and Prevention, the World Health Organization, and many scientific organizations have all determined that thimerosal, when administered in vaccines, is safe.

The preservative has never been part of the MMR vaccine, as is often incorrectly stated. Now, nearly 96% of all flu shots in the United States are thimerosal-free, with only a few kept to serve multi-dose vials for cost-effectiveness and logistical purposes.

Despite this, thimerosal was a rallying cry for anti-vaccine activists, including Kennedy himself. Thimerosal-autism theories have been repeatedly discredited, and the preservative was voluntarily phased out from most childhood vaccines in the U.S. by 2001. Significantly, the rates of autism continued to increase even after the removal of thimerosal, further eroding the supposed connection.

Several large-scale international studies have identified no link between thimerosal and autism or other neurologic problems. A standard flu shot with thimerosal contains approximately 25 micrograms of ethylmercury — half as much mercury as in a 3-ounce tuna can. Ethylmercury is excreted from the body in approximately a week, with no potential for bioaccumulation.

In addition, studies indicate that autism rates have continued to climb even since thimerosal was phased out of children's vaccines in the early 2000s, further refuting the theory that it is responsible for developmental disorders.

Implications for Flu Season and Global Vaccine Supply

Whereas the panel again emphasized that all Americans above six months of age should be vaccinated against flu, the vote will potentially restrict access in some settings. Several clinics, particularly in low-income or rural areas, depend on multi-dose thimerosal-containing vials because they are less expensive and easy to store.

Experts are concerned that the suggestion might trigger unnecessary shortages or access blockages for underprivileged groups. It also has the potential to impact international vaccine policies, especially in low- and middle-income nations where thimerosal-containing vaccines are still important for logistical and economic reasons.

Today, 96% of flu vaccines given in the U.S. are thimerosal-free, with even greater percentages in federal programs such as Vaccines for Children. The majority of children already receive thimerosal-free single-dose vaccines. Nevertheless, the few remaining multi-dose vials are important to maintaining overall vaccine coverage, especially during peak demand or when supplies are low.

Although the U.S. has for the most part abandoned thimerosal, it is still used in most global health programs. The World Health Organization has consistently underscored that thimerosal is safe, especially considering its important role in vaccine integrity in poor-world settings.

Any change in U.S. policy would have a multiplier effect globally, possibly promoting hesitancy and making supply chains more complex.

ACIP's vote is not law, but it is a strong force behind CDC recommendations and insurance payments. It is not clear if the CDC will ultimately endorse the panel's new recommendation. An official announcement from the agency should come before the beginning of next season's flu season.

The resurgence of the thimerosal controversy is an outgrowth of deeper stresses in America's public health system. It is a fundamental conflict between scientific consensus and ideological disruption. As flu season approaches, experts caution against vigilance, not only against the virus, but against disinformation.

Health officials in California have confirmed that a South Lake Tahoe resident tested positive for the plague, the centuries-old disease that killed millions during the Black Death. The individual is believed to have contracted the infection after being bitten by an infected flea while camping near the Lake Tahoe Basin. According to El Dorado County Public Health, the patient is receiving care and recovering at home.

“Plague is naturally present in many parts of California, including higher-elevation areas of El Dorado County,” said Kyle Fliflet, the county’s acting public health director. “It’s important that individuals take precautions for themselves and their pets when outdoors, especially while walking, hiking and camping in areas where wild rodents are present.”

Though most people associate the plague with medieval Europe, the bacterium that causes it—Yersinia pestis—still circulates in parts of the United States. The Centers for Disease Control and Prevention (CDC) estimates an average of seven human cases occur each year nationwide.

Most of these cases are sporadic, linked to fleas feeding on infected wild rodents such as ground squirrels and chipmunks. California, Arizona, New Mexico, and Colorado report the majority of cases. While the disease is now treatable with common antibiotics, untreated infections remain dangerous and potentially fatal.

In El Dorado County, plague activity is not unusual. State monitoring programs have detected Y. pestis exposure in at least 45 wild squirrels and chipmunks in the Lake Tahoe Basin since 2021. Most recent human case of plague in the region occurred in 2020 and was due to flea exposure.

How The Plague Spreads?

Most common way of transmission is by being bitten by an infected flea, but people can also get infected through handling infected animals or less commonly from pets like cats and dogs that are infested with fleas. There are three main forms of plague.

Bubonic plague – Most frequent, resulting from flea bites. The signs and symptoms are painful, swollen lymph nodes (buboes), fever, chills, headache, and weakness.

Septicemic plague – What happens when bacteria multiply in the blood, leading to bleeding beneath the skin, pain in the abdomen, and shock.

Pneumonic plague – Rarest but deadliest variety. It occurs when infection reaches the lungs and can be spread person to person through respiratory droplets.

More than 80% of U.S. cases are bubonic. If diagnosed early, antibiotics such as streptomycin, doxycycline, or ciprofloxacin can cure the disease. Without treatment, however, mortality remains high.

The term "plague" usually brings to mind the Black Death that caused an estimated 25 million deaths in Europe in the 14th century. That epidemic spread quickly from rat and flea populations in densely populated cities.

In the United States, the most recent rat-to-human plague outbreak took place in Los Angeles in 1924–1925. Since then, cases have been mostly confined to rural settings where people come in contact with wild rodents.

Only last month, an Arizona patient succumbed to pneumonic plague, highlighting that though unusual, the illness remains dangerous, especially when diagnosis is late.

How Did Lake Tahoe Become A Hotspot for Plague

Lake Tahoe’s mix of wilderness, high elevation, and rodent populations makes it one of California’s plague monitoring hubs. The California Department of Public Health (CDPH) routinely tests rodent populations, especially ground squirrels and chipmunks, for signs of Y. pestis exposure.

Officials stress that the presence of plague in wildlife does not mean widespread human danger. Instead, it highlights the importance of preventive measures for campers, hikers, and residents. Recommended precautions include:

• Using insect repellent containing DEET when outdoors
• Wearing long pants tucked into boots to minimize flea exposure
• Avoiding contact with wild rodents, dead animals, or their burrows
• Never feeding squirrels or chipmunks
• Keeping pets leashed or at home, and treating them with flea prevention

The South Lake Tahoe patient’s infection is believed to stem from a flea bite during a recent camping trip. Local health officials are investigating the case and have issued public advisories to remind residents and visitors about safety practices.

While the patient’s identity has not been disclosed, officials confirmed that they are receiving proper medical care and are expected to recover. The case has sparked renewed efforts to remind the public that while plague is rare, awareness is essential.

Is Plague Still A Cause Of Concern?

Globally, plague continues to cause outbreaks, particularly in parts of Africa, Asia, and South America. The World Health Organization reports several hundred cases per year, with Madagascar being one of the most affected countries.

In the United States, where public health infrastructure and antibiotics are readily available, cases are usually isolated and treatable. Still, experts say that ignoring plague entirely would be a mistake. Rodent populations are reservoirs for the bacterium, and climate change, increased outdoor recreation, and human encroachment into wildlife habitats may increase opportunities for transmission.

The South Lake Tahoe case is a reminder that ancient diseases are not fully relegated to history books. But unlike the Middle Ages, modern medicine provides effective tools to treat and contain outbreaks.

For residents and visitors, the takeaway is practical rather than alarmist: enjoy the outdoors but take precautions. For health authorities, it is a call to continue surveillance, public education, and rapid response when rare cases occur.

As Kyle Fliflet put it, “Plague is naturally present in many parts of California…It’s important that individuals take precautions for themselves and their pets when outdoors.”

While viral diseases increase worldwide, scientists are uncovering breakthroughs that could shift the tide. A rare genetic mutation recreated in labs shows potential to make humans nearly immune to viruses, offering hope amid growing global health challenges. This discovery marks a critical step in reimagining future antiviral defenses. What if immunity to nearly all viruses wasn’t science fiction but a possibility hiding inside the cells of a few rare people? That’s the exciting promise scientists are now exploring after recreating a genetic mutation that seems to grant natural resistance to viral infections. In recent experiments, researchers used mRNA technology to mimic this mutation in animals, creating short-term but powerful antiviral protection. The findings, published in Science Translational Medicine, could change the way we prepare for pandemics and treat viral outbreaks.

The story begins with a rare immune disorder called ISG15 deficiency, first identified about 15 years ago by Columbia University immunologist Dusan Bogunovic. At first, the mutation seemed like bad news—it increased vulnerability to certain bacterial infections. But as more patients were studied, something unusual came into focus: these individuals rarely got seriously sick from viral diseases.

Flu, measles, mumps, chickenpox—patients carried evidence in their blood of past viral encounters, yet none recalled being laid up in bed or experiencing the kind of severe illness that typically accompanies these infections.

The secret was a constant, low-level immune activation. Normally, the body’s antiviral proteins are switched on only during an infection. But in ISG15-deficient people, the “on switch” never flips off. Their immune systems exist in a perpetual state of mild inflammation—enough to keep viruses from ever gaining a foothold.

From Rare Condition to Universal Antiviral Blueprint

For years, Bogunovic wondered if this quirk could be harnessed for broader use. “In the back of my mind, I kept thinking that if we could produce this type of light immune activation in other people, we could protect them from just about any virus,” he explained.

That theory now has proof of concept. Using technology similar to COVID-19 mRNA vaccines, Bogunovic’s team designed a therapy that temporarily reproduces the ISG15 effect in healthy animals. Instead of shutting down ISG15 completely—which produces dozens of proteins, not all beneficial—the researchers pinpointed 10 specific proteins responsible for antiviral resistance.

The therapy delivers mRNA instructions, wrapped in lipid nanoparticles, that prompt cells to make those proteins. The result: a body on viral high alert, but only for a few days.

Testing the Antiviral Shield in Animals

In experiments, mice and hamsters received the therapy via a nasal drip. When exposed to influenza and SARS-CoV-2, the animals’ bodies rapidly produced the antiviral proteins, which blocked the viruses at multiple stages of their life cycles.

The results were striking. Viral replication was restricted, disease severity dropped, and—crucially—the rest of the immune system functioned normally. Unlike people naturally born with ISG15 deficiency, the treated animals didn’t show harmful levels of inflammation.

Even more impressive: in lab cultures, no virus tested so far—including flu and coronaviruses—has managed to bypass the defense. “We have yet to find a virus that can break through the therapy’s defenses,” Bogunovic said.

Could This Work Like Powerful Protection For Viral Diseases?

The antiviral protection lasted three to four days—a short window, but potentially a lifesaving one in the right circumstances. Unlike vaccines, which take weeks to build immunity and must be tailored to specific pathogens, this therapy acts quickly and broadly.

That makes it especially promising for pandemic preparedness. Imagine health workers receiving a dose before entering a hospital during an outbreak, or family members protecting themselves while caring for a sick loved one. “We believe the technology will work even if we don’t know the identity of the virus,” Bogunovic said.

In effect, it could serve as a kind of biological personal protective equipment (PPE)—a temporary antiviral shield until traditional vaccines or treatments are developed.

For all its promise, the therapy faces steep challenges. Delivering mRNA precisely to where it’s needed in humans remains one of the toughest problems in biotechnology. In animals, the nasal route worked, but optimizing delivery for people is far from solved.

“Once the therapy reaches our cells, it works,” Bogunovic noted. “But the delivery of any nucleic acid, DNA or RNA, into the part of the body you want to protect is currently the biggest challenge in the field.”

There’s also the question of durability. Protection that lasts only a few days may limit practical use unless it can be safely repeated. Long-term effects on the immune system must also be carefully studied.

And then there’s public trust. The therapy relies on mRNA technology—the same platform behind COVID-19 vaccines—which has faced political and social backlash despite its scientific success. Convincing people to embrace another mRNA-based innovation could be difficult.

Despite these obstacles, the implications are profound. If scientists can refine and safely scale this approach, it could give humanity an entirely new tool against viral threats one not limited to known pathogens or dependent on predicting the next pandemic strain.

Bogunovic envisions a world where doctors could deploy the therapy in nursing homes during flu season, where first responders could be inoculated at the front lines of outbreaks, and where households could shield vulnerable family members when new viruses emerge.

“Our findings reinforce the power of research driven by curiosity without preconceived notions,” Bogunovic said. “We were not looking for an antiviral when we began studying our rare patients, but the studies have inspired the potential development of a universal antiviral for everyone.”

Only a few dozen people on Earth naturally carry the ISG15 mutation, but their biology may unlock a universal antiviral strategy for the rest of us. For now, the work is confined to labs and animal trials But the concept that a rare genetic glitch could be recreated to protect against virtually any virus is a remarkable reminder of how much nature still has to teach us.

The Food and Drug Administration just approved the first-ever glucose monitoring system specifically for weight loss, establishing a new option for Americans to manage their weight. Until now, the main options have been expensive obesity drugs like Wegovy and Zepbound or surgical interventions both usually limited to people with a certain BMI. Even then, access is tough: high price tags, patchy insurance coverage, and limited supply often put these treatments out of reach.

Could a wearable device that tracks your body’s glucose in real time open up a more accessible, personalized way to manage weight? This approval suggests the answer might finally be yes.

Continuous glucose monitors (CGMs) were designed as lifesaving devices for people living with diabetes. They eliminate the need for constant finger-prick tests, instead offering near real-time blood sugar readings through a small wearable sensor. For individuals managing type 1 diabetes, type 2 diabetes on insulin, or gestational diabetes, this technology has transformed daily life—improving safety, flexibility, and long-term health outcomes.

But lately, CGMs are appearing on the arms of people who don’t have diabetes. Celebrities, elite athletes, and wellness influencers are adopting these devices in the name of performance, longevity, or “biohacking.” While the movement reflects a growing cultural obsession with data-driven health, experts are increasingly asking: is this medical technology being used responsibly—or is it being misapplied in ways that provide more confusion than clarity?

What Is Glucose?

To understand the debate, it helps to revisit the basics. Glucose is the body’s main source of energy, fueling muscle, brain, and organ function. Think of it like gasoline for a car: too little, and the system stalls; too much, and long-term damage builds up.

In healthy individuals, the body keeps glucose within a safe range by releasing insulin, a hormone made in the pancreas that helps shuttle glucose from the bloodstream into cells. For those with diabetes, this regulatory system is impaired, which makes constant monitoring critical.

Even without diabetes, blood sugar naturally fluctuates throughout the day depending on meals, physical activity, stress, illness, or even puberty. These swings are normal. What’s not normal is chronic dysregulation—something CGMs were designed to help patients detect and manage.

How Continuous Glucose Monitors Work?

Traditionally, people with diabetes relied on finger-prick testing several times a day. CGMs replaced much of that burden. A small sensor, often worn on the arm or abdomen, measures glucose levels in the fluid between cells every few minutes. The data is sent to a reader or smartphone app, allowing patients to track trends, prevent dangerous highs or lows, and adjust treatment accordingly.

For someone with type 1 diabetes, this technology can be the difference between life and death. It allows immediate action when glucose drops during sleep or spikes after meals. For pregnant women with gestational diabetes or people with type 2 diabetes on insulin, CGMs have also been shown to improve outcomes and reduce complications.

How Does A Wellness Tracker Work Without Diabetes?

Now, CGMs are crossing over into the wellness market. High-profile users—from tech CEOs to pro athletes—praise the devices for giving insights into how food, exercise, and stress affect their glucose patterns. Apps connected to CGMs often promise personalized nutrition advice or “metabolic optimization.”

There is some appeal: glucose spikes after eating highly processed carbohydrates or sugary foods can leave anyone feeling sluggish, and seeing that spike in real time can reinforce healthier food choices. For endurance athletes, monitoring glucose may help optimize fueling strategies during long events.

But the scientific evidence in support of CGM use among healthy individuals is lean. A 2022 study published by the University of the Sunshine Coast concluded that CGMs offered little clinically significant benefit for non-diabetic athletes. More recently, scientists examining international data in 2024 cautioned that promotional suggestions for CGM use in healthy populations might be "misleading," considering how little proven outcomes exist.

Is There Any Potential Downsides of Over-Monitoring

There's a second danger, information overload. For individuals who don't require vigilant watching, the data stream can cause worry or even unhealthy preoccupation. Every rise in blood sugar doesn't need a response—though some users might feel obligated to "correct" every spike, perhaps ending up on a restricting diet or feeling unduly anxious.

Its economic burden is also important. A CGM sensor with a life of just 14 days can be over $100 if it is not covered by insurance or public subsidies in the United States.For individuals without diabetes, that’s a steep price for information that may not translate into measurable health benefits.

Part of the fascination comes from the broader movement toward “biohacking” and quantified health. Wearables like smartwatches, sleep trackers, and fitness rings have made people more comfortable tracking biometric data daily. CGMs fit naturally into this landscape, offering a continuous metabolic data stream that feels cutting-edge and personalized.

Add in celebrity influence—musicians, influencers, and athletes openly wearing CGMs in interviews or on social media—and public interest has surged. For some, it represents empowerment: a way to take control of invisible processes in the body. For others, it’s simply the latest wellness trend in a crowded marketplace of supplements, gadgets, and health apps.

It’s worth noting why CGMs appeal to so many people. Nearly 74% of Americans are overweight or obese, according to government data, with obesity-related conditions costing the U.S. healthcare system more than $170 billion annually. With metabolic health under such strain, many are searching for tools to stay ahead of potential problems.

CGMs may feel like a proactive solution but experts caution that prevention is less about constant glucose monitoring and more about proven strategies: balanced nutrition, physical activity, adequate sleep, and routine medical check-ups. For now, CGMs aren’t a shortcut to better health if you don’t already have a condition requiring them.

Should People Without Diabetes Use CGMs?

The answer isn’t black and white. For individuals with diabetes, CGMs are life-changing and medically essential. For those without diabetes, the benefits are mostly speculative, while the risks anxiety, cost, and misuse of data are very real.