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Do milder winters mean Lyme disease season lasts all year?

The lack of snow cover and mild winter weather that has people trading in snowshoes and skis for hiking boots, and shovels for gardening rakes, is also increasing their exposure to Lyme disease year-round, scientists say.

“We have had weather conditions very conducive for exposure risk,” says Larry Dapsis, an entomologist in Massachusetts who has produced a series of videos on ticks and tick-borne disease prevention.

The deer ticks that cause Lyme and other diseases are active when temperatures hit 40 degrees, or maybe even a bit lower, Dapsis says.

Warmer winters, more tick activity

And when they emerge from the leaf litter, “they are going to be very hungry” and looking for a blood meal, says Constantin Takacs, an assistant professor of biology at Northeastern University who studies the borrelia burgdorferi bacterium that causes Lyme disease.

Climate change means fewer freezing temperatures across the U.S. In fact, winter was the fastest warming season for 74 of 246 locations analyzed by Climate Central for a Jan. 25 report.

And what of the recent cold snap that sent temperatures plummeting well below freezing in parts of the Northeast where Lyme disease is endemic?

As life-threatening as the weather was in terms of human exposure, it likely did not deliver much of a death blow to the deer tick population, Takacs and Dapsis say.

“They go into the ‘blanket’ of leaf litter,” Takacs says, adding, “The ones that dig very, very deep in those leaf mounds are going to survive, no matter how cold the temperature is.”

“The ones that stay close to the surface will be killed by long periods of subfreezing temperatures,” he says. But “the fewer the number of very cold days there are, the more likely larger numbers of ticks will survive the winter.”

Ticks make their own antifreeze

Deer ticks also have a secret weapon—a naturally occurring type of antifreeze, Dapsis says.

“They make a chemical called glycerol. That reduces the freezing point temperature of their cells,” says Dapsis, who coordinates the tick project for the Cape Cod Cooperative Extension.

That means that even the sub-freezing temperatures experienced in the Northeast Friday and Saturday didn’t kill ticks hidden in the ground and forest floor, Dapsis says.

“They burrow down. They’re happy. When it’s warm enough they’ll come up looking for dinner,” he says.

Ticks don’t burrow up through snow, but this year has seen precious little snow cover in southern New England and other parts of the country.

Dapsis says he tells people to take protective measures against tick exposure whenever it’s above freezing and the ground is bare.

Winter ticks carry lots of Lyme  

The deer ticks that emerge in winter are in the adult stage and looking to make a blood meal out of large mammals, including deer, coyotes, dogs—and humans.

“The adult stage ticks prefer a larger host,” Dapsis says.

He says adult ticks also are more likely to carry the pathogen responsible for Lyme disease than the nymphal ticks that emerge in mid-May, and they have an infection rate of 50% versus 20% to 25%.

The nymphal stage ticks are responsible for 85% of Lyme disease cases, mainly because their size—that of a poppy seed—makes them so hard to see, Dapsis says.

But he says adult ticks aren’t that much larger, approximately the size of a sesame seed, so it’s important to take precautionary measures such as wearing shoes and pants treated with the insecticide permethrin and doing tick checks after spending time outdoors.

Protect yourself and pets

“I tell people to tick check year-round, especially in a milder climate like southeastern Massachusetts,” says Dapsis.

In a series of 10 tick disease prevention videos available on Youtube and through Barnstable County, Dapsis demonstrates how to treat clothing with permethrin and discusses the importance of wearing repellent on bare skin and protecting pets.

Hikers may balk at the optics of one common piece of tick prevention, which is to pull socks—preferably light colored for better tick detection—up over their pants.

But creating a barrier between oneself and the creepy, crawly eight-legged ticks that more closely resemble spiders than six-legged insects is a good idea, Takacs says.

“We should keep going in nature and be outdoors,” he says. “When we come back, we do a tick check. We take a hot shower. People need to be aware of the dangers that come with (ticks’) presence and how to be safe around them.”

This article originally appeared on Northeastern Global News

Photo by Getty Images & Matthew Modoono/Northeastern University


February 06, 2023

Tom Brady without football: A look at the psychology of a retiring athlete

Twenty-three seasons and seven Super Bowl rings later, quarterback Tom Brady is hanging up his jersey and donning civilian clothes. His retirement announcement on Wednesday comes a year after the 45-year-old football star initially said he was stepping away from the sport before committing again to what would be a final season with the Tampa Bay Buccaneers.

Even a sporting megastar like Brady, widely considered the greatest quarterback of all time, faces uncertainty when making the  leap from public celebrity to private citizen.

But Brady, who for years has said he wanted to play football past the age of 40, has built a legacy on sporting longevity, planning for retired life while he was still chasing championships with the New England Patriots and Buccaneers, says Grayson Kimball, a psychology professor at Northeastern who also works as a mental performance coach.Dr. Greyson Kimball

“He has, over the last five or so years, laid out his post-retirement plan” while still playing, Kimball says. “He’s got the TB12 brand; he now has a clothing line. He knows what he’s doing. He’s been planning for this.”

It’s true. The success of Brady’s business ventures, coupled with the career earnings, more than ensures he will be financially comfortable in life after football—and perhaps even busier than he imagines. It’s a phase likely to be filled with new meaning and fulfilling replacement activities, the quarterback said over Instagram last year, when he first considered retirement, adding: “I have loved my [National Football League] career, and now it is time to focus my time and energy on other things that require my attention.”

But for many athletes, retirement can be sudden and unplanned, leading to higher rates of mental-health and substance-abuse issues. It’s more often the case that athletes are forced out of competition because of injury, or are discarded as has-beens and displaced by younger talent, Kimball says.

“It’s rare that an athlete goes out on their own terms,” he says. “Many times you’ll hear that so-and-so retired because of an injury. That they tried to come back and just couldn’t do it.”

The average career length for an NFL player is between three and four years, and about 78 percent of players go broke within three years of retirement, according to data from the National Bureau of Economic Research.

Average career length is only slightly longer for National Basketball Association players—and for baseball players, it’s even less. While organizations like the NFL do have career-transition services in place to help players plan their post-football futures, they’re hardly used, Kimball says.

“There are services available,” Kimball says. “But do the athletes take advantage of it? The answer is no.”

The question of how athletes—professional and college alike—fare emotionally after they step away from sport is really a discussion about meaning and identity, says Jeff Levin, a psychotherapist and life coach who’s worked closely with Northeastern student-athletes.

“My feeling is that when you’re at a level like that, and your job depends upon success—when that goes away, it’s definitely a loss from the ego standpoint,” Levin says. “I think people need to go through a grieving process.”

Levin says the pressures on young athletes, such as those who have not yet turned professional, to succeed can have devastating consequences on their mental health. These pressures are a product of a culture of “hero worship,” he says. Even upper-echelon college athletes today can make money on “their likeness and image” in the ways professional athletes do, Levin says.

“The athletes I know, who are under the age of 30, have ‘outcome fever,’” he says. “They’ve been raised to put all of their eggs in the athletic basket. And when it doesn’t work out for them, they can get into serious trouble.”

So how will Brady do when his fame and popularity fade away?

“How the inside of his head works—I have no idea,” Levin says. “As much as he preaches about focus and humility, he’s clearly literally capitalized on his fame. I hope he can retain his humility and find peace.”

This article originally appeared on Northeastern Global News

Photo by Adam Glanzman/Getty Images & Matthew Modoono/Northeastern University

February 02, 2023

Can ‘digital traces’ from internet searches and social media predict outbreaks of COVID-19?

Your Google searches and Twitter accounts alert marketers about what items you might like to  purchase—could they also serve as an early warning system when COVID-19 levels are about to take off?

A team of scientists including Northeastern University machine learning expert Mauricio Santillana says internet users’ “digital traces” can be adopted to alert public health officials to sharp increases in COVID-19 at the county level one to six weeks ahead of a major outbreak.

In a paper published Wednesday, Jan. 18, in Science Advances, Santillana and other authors say digital data will help close information gaps left by existing surveillance methods.

Analysis of the data streams will allow policymakers to get a jump on decisions such as whether to reissue masking recommendations or bump up vaccination and boosting campaigns, says Santillana, director of the Machine Intelligence Group for the Betterment of Health and the Environment at the Network Science Institute at Northeastern

“What we aspire to do is to use the same information that Google or Amazon or any of these big firms use to send ads to you” to inform public health decisions early on in an outbreak, Santillana says.

COVID-19-related digital streams include internet searches for fever, clinician searches for COVID-19 treatments and Twitter users’ comments about being too sick to work, among other things.

The researchers also used machine learning methods that took historic information from outbreaks in 97 U.S. counties from Jan. 1, 2020, and 2022 and combined them to create a single predictive indicator.

“The goal is not necessarily to quantify how many infections there are but to quantify when sharp increases in infections will happen,” says Santillana, who participated in the research with scientists from Boston Children’s Hospital, Harvard Medical School, Oklahoma State University and other organizations.

Researchers found that the predictive capacity at the state and county levels was roughly similar—the early warning system deployed at one to six weeks in advance at the county level and four to six weeks at the state level.

The study says the digital data will help fill in vital missing information for the Centers for Disease Control and Prevention, which it says has failed to reliably forecast “rapid changes in the trends of reported cases and hospitalizations.”

“When CDC COVID-19 forecasts were shared with the public, they very frequently missed the timing of when outbreaks were starting,” Santillana says. He says by the time actual case numbers were tallied, surges were already well under way.

“The next chapter would be for the CDC to say, ‘We know that this is an alternative and complementary way to anticipate outbreaks. We will implement it inhouse, and we will have it as an additional tool in our toolbox,” Santillana says.

“He says the study is part of a new CDC initiative started by President Biden called the Center for Forecasting and Outbreak Analytics within the CDC.”

“It is within that effort that we did the work in this paper,” published in an open access journal of the American Association of the Advancement of Science, Santillana says.

He says he and his team already had been working with the CDC for three to four years on predicting flu incidence and flu hospitalizations, but he wasn’t satisfied with what he considered the CDC’s inability to incorporate novel Internet-based sources of information into their prediction systems.”

“When COVID hit, they called and said, ‘We need all hands on deck. So please do what you can.’”

“I asked if they could be flexible, because my team and I were interested in innovating rather than just continuing to implement the exact same models,” Santillana says.

“The model is not perfect,” he says

The counties studied were only a fraction of the 3,006 counties in the United States, according to the paper on using digital traces to build prospective and real-time county-level early warning systems.

“Our internet search-based methods may struggle to perform well in areas with poor literacy rates and limited access to internet resources,” the paper says.

The researchers say a possible solution for counties with poor internet access or literacy challenges may be to use state-level early warning systems to guide county-level decisions around outbreaks.

“When we navigate the internet on our computer or phone it leaves traces,” Santillana says.

“Whether we like it or not, the reality is that most companies use this information to increase their profit or their margins,” he says.

“Instead, we want to use that information to inform public officials when the next outbreak will happen.”

This article originally appeared on Northeastern Global New

Photo by Matthew Modoono/Northeastern University


January 18, 2023

The fungal zombies in HBO’s ‘The Last of Us’ are based on real, horrifying biology

In the premiere of HBO’s big budget video game adaption “The Last of Us,” a scientist on a 1960s Dick Cavett-like talk show raises the idea that a fungal, not viral, infection will spell the end of humanity. On the surface, it’s laughable, and the idea is met with bemused laughter by the host and audience.

But as the scientist explains his theory, the energy in the room slowly shifts from amusement to horror. All it would take is for one gene in a fungus to mutate and suddenly it “could become capable of burrowing into our brains taking control not of millions but billions of us,” he says. “Billions of puppets with poisoned minds, permanently fixed on one unifying goal: to spread the infection to every last human alive by any means necessary.”

The scientist goes on to say there are no treatments or cures for this kind of infection. There’s only one possible conclusion: “We lose.”

In the world of “The Last of Us,” those words are prophetic. In 2003, a fungal infection ravages the world, turning humans into ravenous, mind-controlled zombies. HBO’s latest hit, and the game that it’s based on, might sound like pure science fiction, but it’s actually based on real, horrifying science.

The developer behind “The Last of Us,” Naughty Dog, took inspiration for its fungal zombies from the cordyceps fungus. A kind of parasitic fungus that infects insects and, in some cases, plants, it’s nature’s zombifying agents

The spores dispersed by the cordyceps sit in the soil and attach to the bodies of insects. Over the course of 24 to 48 hours, the parasite grows into the body of the insect, before spreading throughout the body over the course of a few weeks.

“It already starts changing the neurobiology of the host so that it basically makes it a zombie organism, meaning this parasite takes over, producing some kind of neurotoxins or neuromodulators that change the behavior of the host,” says Rebeca Rosengaus, associate professor of marine and environmental sciences at Northeastern.

The parasite surrounds the muscles of an insect, affecting its motor neurons and turning the host into a marionette. David Hughes, an entomologist who consulted on “The Last of Us” game, says there are clear similarities between the fictional infected and how the parasite operates in the ants he studied.

At first, infected humans in “The Last of Us” don’t immediately display signs of infection. However, that quickly changes. They start twitching and become hyperaggressive and overly energetic. Survivors in “The Last of Us” call those infected in this stage “runners.”

This behavior is somewhat based in reality, Hughes says. The cordyceps parasite releases a chemical compound that causes insects to twitch and convulse.

“They do not enter the brain, but what they do is push chemicals into the brain across the blood-brain barrier so that they can control the brain at a distance,” Hughes says.

Ants infected with the cordyceps parasite also start becoming more antisocial, a notable shift in highly social ant societies, and wander off from the rest of the colony. Similarly, the show’s infected humans lose all ability to speak and, instead, scream and shriek in rage and pain.

But the parasite isn’t just forcing the host to wander mindlessly. There’s intent and purpose behind where infected ants—and their fictional counterparts—roam.

Ants are very adept at detecting infected members of their colony through changing chemicals and scents. If an ant is sick, it is killed and its body is deposited outside the colony. In order to circumvent that, the parasite needs to make its host die outside the colony if it has any hope of infecting more hosts.

This manifests in a behavior called summiting. The infected host will climb to a certain height before lodging its mandibles in a branch, stem or leaf. Up until this point, the host was still alive but totally unable to control its movement. However, at this point, the fungus starts eating the host alive from the inside before sprouting a long tendril-like stalk with a “fruiting body” that disperses spores. From on high, the spores catch on the wind and can infect an even larger area.

“The ants are forced every day to go out looking for food, so as they go out, they walk underneath a sniper’s alley of their dead siblings, which are hanging underneath the underside of the leaf, producing spores,” Hughes says. “You can imagine a dome of death which is surrounding the colony that the ants have to pass through every day, and this is why the fungus is winning.”

Although the 2013 video game featured spores as a method of infection, HBO’s adaptation of the “The Last of Us” has done away with them, marking the biggest departure from its scientific inspiration.

As for whether we’ll ever have to face a fungal zombie outbreak, Hughes says there’s no reason to worry. The motor systems of ants and humans are different enough that the cordyceps can’t make the leap into humans—but that doesn’t mean fungi can’t affect our behavior or even infect our bodies.

LSD is, of course, derived from hallucinogenic fungi. But other kinds of fungi can have a much more dangerous effect. The coccidioides fungus causes a condition called Valley Fever when inhaled and has been found, notably, in California prisons.

In 2022, the World Health Organization released its first list of health-threatening fungi, which included 19 fungi that “represent the greatest threat to public health.” According to the report, fungal infections kill about 1.6 million people per year and present a particular danger for severely ill patients who are already immunocompromised. The frequency and geographic range of fungal diseases are also on the rise, due to global warming and an increase in international travel and trade.

Emerging from the shadows of the bacterial antimicrobial resistance pandemic, fungal infections are growing, and are ever more resistant to treatments, becoming a public health concern worldwide,” says Dr. Hanan Balkhy, WHO’s assistant director of antimicrobial resistance

While fungal infections are becoming more common, the idea of a fungal apocalypse is still the stuff of science fiction, Hughes and Rosengaus agree. However, Rosengaus says fungal parasites can still provide a new lens through which to look at more common viral infections like the flu or even COVID-19. There’s a reason we sneeze and cough while we have the flu.

“The word that we call ‘symptoms,’ yes, they’re symptoms of the disease, but the question I think is interesting to ask is, are these symptoms really the reflection of the [virus] manipulating our physiology, our behavior, in order to be more helpful in transmitting the disease?” Rosengaus says. “It’s astonishing the kind of evolutionary back and forth that these parasites have been able to manage in order to manipulate the behavior of the host.

This article originally appeared on Northeastern Global News.

Photo By HBO Max


January 18, 2023

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