Science

Q&A: Why COVID-19 booster shots turned out to be more complicated than vaccines

Published

3 years ago

March 12, 2022

Q&A: Why COVID-19 booster shots turned out to be more complicated than vaccines

Just some months in the past, the safety provided by COVID-19 vaccines introduced Individuals pleasure and reduction, permitting the totally immunized to ditch their masks and return to a semblance of pre-pandemic life. Now that safety appears extra like an phantasm.

What occurred?

Has our vaccine-induced immune response actually fizzled? Is the Delta variant guilty for waning vaccine effectiveness? Is the resurgent dread of COVID-19 warranted? Will booster pictures restore our safety — and the hope that got here with it?

Each the Meals and Drug Administration and the Facilities for Illness Management and Safety grappled with these questions earlier than giving the go-ahead to boosters in sure populations. If that steering appeared disjointed or confused, it was largely as a result of the science remains to be rising.

Issue within the crosswinds of politics, worry, rampant misinformation and a vaccination marketing campaign that has misplaced its momentum, and issues change into much more fraught.

As an example, in declining to suggest {that a} third dose of the Pfizer-BioNTech vaccine be made out there to all who obtained their second dose a minimum of six months earlier, members of a CDC advisory panel made clear they didn’t wish to undermine public confidence in COVID-19 vaccines when so many haven’t even gotten their first dose.

How did we get right here?

Let’s begin by acknowledging that vaccines had been by no means excellent

Even in medical trials, the Pfizer-BioNTech vaccine was reported to be 95% efficient at stopping circumstances of COVID-19. Meaning the chance of changing into sick after getting the pictures was small however not zero — and it doesn’t say something concerning the vaccine’s capability to thwart a coronavirus an infection within the first place.

Furthermore, that lofty determine was unlikely to carry underneath real-world situations. In the US, shut to three% of adults are immune-compromised and subsequently unlikely to mount a robust protecting response to a vaccine. Plus, new viral variants are regularly being incubated domestically or imported from overseas.

Random mutations to the coronavirus’ genome may alter it in ways in which may make it extra transmissible, or improve its capability to make individuals severely in poor health. One other fear is that mutations might change the virus in ways in which stop vaccine-induced antibodies from recognizing it.

The rise of the Delta variant exhibits that scientists are proper to be frightened. In chart after chart, FDA and the CDC specialists cited analysis suggesting that the now-dominant pressure has helped erode vaccines’ effectiveness in myriad methods.

Vaccines have an effect on the immune system in complicated, and mysterious, methods

The primary months following immunization are the heyday for antibodies: They’re plentiful, not too long ago skilled to acknowledge their goal virus, and diversified sufficient to acknowledge a number of of its options. A virus trying to invade is unlikely to sneak previous.

However as that preliminary spate of antibodies decays, the immune system can depend on its reminiscence banks — the legions of white blood cells through which resides the battle plan for preventing a brand new an infection. The looks of a virus ought to immediate these specialised cells to swing into motion. Helper T cells stimulate B cells to provide a contemporary crop of antibodies. In addition they immediate different T cells to search out cells which were contaminated and kill them.

However this course of isn’t instantaneous, and if the coronavirus can set up itself within the nostril and mouth rapidly sufficient, the immune system might not reply quick sufficient to bar the gates. An infection occurs.

For most individuals — however clearly not all — the cavalry will arrive in time to blunt an all-out invasion and head off extreme illness. That will clarify why researchers have discovered that the longer the time since vaccination, the higher the chances that inoculated individuals take a look at constructive for a coronavirus an infection, despite the fact that the speed at which they’re being hospitalized for COVID-19 has risen a lot much less steeply.

This sample has been noticed in Israel, Qatar and the US. In a single examine that targeted on New York, the three out there vaccines’ mixed capability to stop an infection fell from 92% in early Might to about 77% in late August, and the decline was seen in all age teams. But throughout the identical interval, when age was taken into consideration, the vaccines’ effectiveness in stopping hospitalization held regular. (By mid-June, nonetheless, hospitalization charges amongst vaccinated adults over 65 did start to climb.)

In the case of immunity, age issues

Immunity typically weakens as we become old, and so does our response to vaccines. Each of these information have been key within the present pandemic.

Earlier than vaccines turned out there, individuals 65 and older had been by far probably to die of COVID-19. In order that they had been among the many first Individuals to get vaccine — and notably the Pfizer-BioNTech vaccine, which turned out there first.

That makes senior residents the age group furthest out from vaccination. And with clear proof that they’re as soon as once more susceptible to extreme COVID-19, advisors to the FDA and CDC agreed that these 65 and up who obtained their second dose of the Pfizer-BioNTech vaccine a minimum of six months earlier ought to have a booster shot of that vaccine made out there to them.

A examine by the CDC suggests this group is amongst these most in want of booster pictures. For these 65 and over within the U.S. who obtained the Pfizer-BioNTech vaccine, the safety in opposition to being hospitalized for COVID-19 fell from 86% between January and Might to 73% between June and August.

Older Individuals who obtained the Moderna vaccine fared higher: Their safety declined from 91% to 86%, a distinction too small to be statistically important.

For probably the most half, the Moderna vaccine held up higher than the Pfizer-BioNTech one among age teams, although all the adjustments had been sufficiently small that they may have been because of probability.

The reason for this pattern is under no circumstances clear. It may replicate the significance of age, the size of time since vaccination, or the actual vaccine they obtained.

Dose most likely issues too

Different variables possible play a job in a vaccine’s longevity, although scientists nonetheless have a lot to be taught. As an example, does the variety of occasions a vaccinated particular person is uncovered to the coronavirus have an effect on his or her danger of an infection? Does the quantity of virus matter? Do these (or different) components affect the chance of changing into severely in poor health?

The solutions are of important curiosity to healthcare employees and others with important jobs who’re in frequent contact with individuals who might carry the virus. If vaccine safety may be overwhelmed by frequent or excessive doses of the virus, these employees may need periodic refreshers so long as the pandemic continues.

The uncertainty was mirrored in final week’s regulatory actions concerning booster pictures.

On Wednesday, the FDA amended its emergency authorization for the Pfizer-BioNTech vaccine to permit the usage of a booster in adults “whose frequent institutional or occupational publicity to SARS-CoV-2 places them at excessive danger of significant problems” of COVID-19.

The next day, the CDC’s Advisory Panel on Immunization Practices voted in opposition to an equivalent proposal after a number of panel members argued there was not sufficient proof these employees would profit. However inside hours, CDC Director Dr. Rochelle Walensky put aside that recommendation and signed off on offering these employees entry to boosters.

What’s true for the Pfizer-BioNTech vaccine will not be true for others

Three vaccines defend Individuals, and so they’re every distinctive.

Those made by Pfizer-BioNTech and Moderna use mRNA to instruct cells to make a bit of the coronavirus that’s sufficiently big to coach the immune system to acknowledge it, however far too small to do any injury.

Past that, the 2 vaccines are formulated otherwise. The Pfizer product incorporates 30 micrograms of vaccine, an quantity that’s the identical for all three doses. Moderna’s first and second pictures have 100 micrograms of vaccine, however its booster dose incorporates 50 micrograms.

The timing of pictures additionally differs. Pfizer’s first two doses are given three weeks aside, and Moderna’s are spaced 4 weeks aside.

Vaccine specialists have begun to counsel that giving the immune system extra time to reply to an preliminary dose earlier than giving the second may make for stronger, and presumably extra sturdy, immunity. The extra week between Moderna doses could be an essential cause for that vaccine’s comparatively higher endurance.

Both manner, a interval of six months between the second and third pictures could also be even higher for inducing lasting immunity.

The only-dose Johnson & Johnson vaccine makes use of a extra conventional vaccine design — a innocent chilly virus with a payload that introduces the immune system to the SARS-CoV-2 spike protein.

In its opening days, the vaccine was discovered to scale back the chance of symptomatic an infection by 66%, and a later examine reported that it decreased the chance of extreme illness in individuals over 50 by 68%.

There’s some proof that the Delta variant has decreased its effectiveness, though a examine sponsored by J&J confirmed {that a} single jab decreased the chance of COVID-19 by 79% with none decline because the Delta variant rose to prominence. A big examine revealed by the CDC discovered that safety in opposition to hospitalization fell to 60% after Delta turned dominant within the U.S.

Final week, J&J launched preliminary findings of a giant examine that examined the worth of including a second jab. None of those that obtained a booster shot 56 days after their preliminary dose developed a extreme or important case of COVID-19. Amongst examine individuals in the US, the booster decreased the chance of reasonable illness by 94%.

Science

Panama Canal’s Expansion Opened Routes for Fish to Relocate

Published

3 hours ago

January 7, 2025

Press Room

Panama Canal’s Expansion Opened Routes for Fish to Relocate

Night fell as the two scientists got to work, unfurling long nets off the end of their boat. The jungle struck up its evening symphony: the sweet chittering of insects, the distant bellowing of monkeys, the occasional screech of a kite. Crocodiles lounged in the shallows, their eyes glinting when headlamps were shined their way.

Across the water, cargo ships made dark shapes as they slid between the seas.

The Panama Canal has for more than a century connected far-flung peoples and economies, making it an essential artery for global trade — and, in recent weeks, a target of President-elect Donald J. Trump’s expansionist designs.

But of late the canal has been linking something else, too: the immense ecosystems of the Atlantic and the Pacific.

The two oceans have been separated for some three million years, ever since the isthmus of Panama rose out of the water and split them. The canal cut a path through the continent, yet for decades only a handful of marine fish species managed to migrate through the waterway and the freshwater reservoir, Lake Gatún, that feeds its locks.

Then, in 2016, Panama expanded the canal to allow supersize ships, and all that started to change.

In less than a decade, fish from both oceans — snooks, jacks, snappers and more — have almost entirely displaced the freshwater species that were in the canal system before, scientists with the Smithsonian Tropical Research Institute in Panama have found. Fishermen around Lake Gatún who rely on those species, chiefly peacock bass and tilapia, say their catches are growing scarce.

Researchers now worry that more fish could start making their way through from one ocean to the other. And no potential invader causes more concern than the venomous, candy-striped lionfish. They are known to inhabit Panama’s Caribbean coast, but not the eastern Pacific. If they made it there through the canal, they could ravage the defenseless local fish, just as they’ve done in the Gulf of Mexico and the Caribbean.

Already, marine species are more than occasional visitors in Lake Gatún, said Phillip Sanchez, a fisheries ecologist with the Smithsonian. They’re “becoming the dominant community,” he said. They’re “pushing everything else out.”

Science

Sitting hurts. Train for your desk job with these 5 easy exercises for your head and neck

Published

4 hours ago

January 7, 2025

Press Room

Sitting hurts. Train for your desk job with these 5 easy exercises for your head and neck

It’s Monday morning, the start of your work week. You’ve put the finishing touches on that big report, prepared for that imminent presentation. But it’s likely that there’s one aspect of the job you’re not ready for: the marathon of sitting at your desk all day.

Time to start training. Because while it might not be earthshaking news, it bears repeating: Prolonged desk work can lead to a host of musculoskeletal issues, from annoying aches and pains to injuries.

Even if your work space is ergonomically correct — and even if you exercise regularly in your free time — excessive desk work (considered three or four continuous hours) can lead to weakened, tight muscles, joint stiffness, inflammation in the muscles and tendons and tight fascia (connective tissue). Add it all up, and the result is typically some level of discomfort.

Left untreated, muscles that are stressed and deconditioned can lead to painful soft tissue problems, such as tendonitis and carpal tunnel syndrome, as well as chronic lower back pain. You can also become at risk for bulging or herniated discs, pinched nerves and other issues.

Desk work can also lead to biomechanical imbalances. Weakened glutes from sitting, for example, can lead to stress on the knees and lower back; tired hip flexors can alter pelvic movement, leading to lower back pain.

Which is concerning seeing as sitting for work is both on the rise and can put us at risk for other serious health issues, says Stella Volpe, president of the American College of Sports Medicine.

“We know that there are more Americans now that have sedentary jobs than ever in the past,” Volpe says. “The more we sit, the greater risk we have of diabetes, obesity and cardiovascular disease.”

Blame our sitting-related woes on the advent of furniture, says David Raichlen, a USC evolutionary biologist who studies sedentary behavior and exercise.

Before chairs with a back and arm rests debuted as a status symbol among ancient Egyptians about 5,000 years ago, he says that humans mostly kneeled or squatted for about 2 million years. Those resting postures require light muscle activity, but when the body is fully supported by a chair or a couch, it turns off that activity in the body parts being supported by the furniture, Raichlen says. Prolonged inactivity can then lead to muscle atrophy and other problems.

“From an evolutionary standpoint, the human body hasn’t yet adapted to furniture,” Raichlen says. “It never had to deal with completely inactive muscles for long periods of time until very recently.”

But the good news is you can train for long-distance sessions at your desk by working out your neck, your wrists, your lower back, even your feet and toes. These “exercise snacks,” as trainers call them, don’t require a trip to the gym, or equipment, or even much time.

They’re not meant to replace regular exercise, but they will — if done regularly — prepare your body for the challenge that is desk work by stretching and strengthening your muscles, taking pressure off your joints and reducing stiffness and inflammation in the area — all of which may alleviate pain and prevent new injuries.

“We’re designed to be hunter-gatherers, not to wiggle our fingers on a keyboard for eight hours straight,” says Dr. Joshua T. Goldman, a UCLA sports medicine physician. “We need to build up strength, for endurance purposes, to help those body parts tolerate that activity.”

“The human body hasn’t yet adapted to furniture. It never had to deal with completely inactive muscles for long periods of time until very recently.”

— David Raichlen, USC evolutionary biologist

We spoke to exercise physiologists, sports medicine physicians, personal trainers, physical therapists and others to devise a short, five-minute exercise routine for six key regions of the body. We’ll roll out one routine a week — starting with the head and neck area — for six weeks, until you have a complete full-body workout.

Each exercise is purposefully simple, meant to take 30-60 seconds. And each routine lasts about five minutes or less in total. They’re ideally done throughout the day, so as to promote mobility and circulation, bringing blood flow and nutrients to the muscles and tendons, and increasing lubrication in the joints. Set a timer. Take a five-minute break to execute one routine. Then get back to work.

Still too busy? Do just one exercise, for 30-60 seconds, then continue working. If you get through one routine by day’s end, consider it a win. Focus on a different routine the next day.

“It all adds up,” Volpe says. “Our society often thinks that if you’re not running a marathon, you’re not doing enough. But the additive effect is still good for you.”

A routine for your head and neck

The neck is a common area in which to develop pain from desk work. Looking at a computer monitor, we often jut our neck forward rather than tucking in our chin, as we should. That pushes our cervical column out of alignment and creates excess stress on the bones and discs of the cervical spine. It shortens and tightens muscles in the neck, which can lead to pain and cause tension headaches.

Do these exercises to help stretch and strengthen the muscles that support your head and neck. They’re demonstrated by trainer Melissa Gunn, of Pure Strength LA, whose team trains desk workers on how to protect their bodies through exercise.

Clasp your hands behind your head and gently tuck your chin down toward your chest. Hold 10 seconds. Do five times.

Slowly tilt your head to the left, bringing your ear toward your shoulder. Hold for 10 seconds, then raise it slowly back up to the starting point. Switch sides. Do three times on each side. To increase the stretch, after bringing your ear to your shoulder and holding, turn your head and look down toward your armpit on the same side, then return to starting position.

Place your back flat against a wall and stand with your feet about eight inches from the wall, with knees slightly bent. Your arms should be flush against the wall, with palms facing outward. Tuck your chin slightly and push your head gently against the wall. Slide your arms up the wall, as if doing a snow angel. Go as far as you can with your arms and hands flush against wall. Stop when they begin to pull away from the wall — typically when palms are between shoulder height and head height. Do 10 times.

Stand up straight and align your head, shoulders, hips and ankles — most people jut their neck forward without knowing it, creating static tension there, so consciously move your head back so it’s above your shoulders. Slowly roll your head in a circle, first to the left, clockwise, all the way around; then to the right, counter-clockwise. Do 3 times on each side.

Stand up straight and align your head, shoulders, hips and ankles. Your arms should be beside you and your palms facing outward. Then pull your arms back but no further than the back pockets of your pants — without lifting your shoulders — and draw your shoulder blades together. Hold for 2-5 seconds. Do 5-10 times.

(Exercises came from Dr. Joshua T. Goldman, UCLA sports medicine; Melissa Gunn, Pure Strength LA; Tom Hendrickx, Pivot Physical Therapy; Vanessa Martinez Kercher, Indiana University-Bloomington, School of Public Health; Nico Pronk, Health Partners Institute; Niki Saccareccia, Light Inside Yoga.)

Science

Lead Poisoning May Have Made Ancient Romans a Bit Less Intelligent

Published

10 hours ago

January 7, 2025

Press Room

Lead Poisoning May Have Made Ancient Romans a Bit Less Intelligent

Roughly 2,000 years ago, the Roman Empire was flourishing. But something sinister was in the air. Literally.

Widespread pollution in the form of airborne lead was taking a toll on health and intelligence, researchers reported on Monday in the journal Proceedings of the National Academy of Sciences.

During the roughly two centuries starting in 27 B.C., a period of relative stability and prosperity known as the Pax Romana, the empire extended throughout Europe, the Middle East and North Africa. Its economy relied on silver coinage, which required huge mining operations.

But extracting silver from the Earth creates a whole lot of lead, said Joseph McConnell, an environmental scientist at the Desert Research Institute, a nonprofit group based in Nevada, and the lead author of the new research. “If you produce an ounce of silver, you’d have produced something like 10,000 ounces of lead.”

And lead has a host of negative effects on the human body. “There is no such thing as any safe level of lead exposure,” said Deborah Cory-Slechta, a neurotoxicologist at the University of Rochester Medical Center who was not involved in the research.

Dr. McConnell and his colleagues have now detected lead in layers of ice collected in Russia and Greenland that date to the time of the Roman Empire. Lead entered the atmosphere from Roman mining operations, hitched a ride on air currents and eventually fell out of the atmosphere as snow in the Arctic, the team surmised.

The levels of lead that Dr. McConnell and his collaborators measured were extremely low, roughly one lead-containing molecule per trillion molecules of water. But the ice samples were collected thousands of miles from southern Europe, and lead concentrations would have been highly dispersed after such a long journey.

In order to estimate the amount of lead originally emitted by Roman mining operations, the researchers worked backward: Using powerful computer models of the planet’s atmosphere and making assumptions about the location of the mining sites, the team varied the amount of lead emitted to match the concentrations they measured in the ice. In one case, they assumed that all silver production took place at a historically important mining site in southwestern Spain known as Rio Tinto. In another case, they presumed that silver mining was equally spread out across dozens of sites.

The team calculated that anywhere from 3,300 to 4,600 tons of lead were being emitted into the atmosphere each year by Roman silver-mining operations. The researchers then estimated how all that lead would be scattered across the Roman Empire.

“We ran the model in the forward direction to see how those emissions would be distributed,” Dr. McConnell said.

With those atmospheric-lead concentrations in hand, the researchers next used modern-day data to estimate how much lead would have entered the bloodstreams of people in ancient Rome.

Dr. McConnell and his colleagues focused on infants and children. Young people are particularly susceptible to taking up lead from their environment via ingestion and inhalation, said Dr. Bruce Lanphear, a public heath physician at Simon Fraser University in British Columbia who was not involved in the research. “Pound for pound, children, particularly infants, eat more and breathe more.”

In recent decades, lead levels in children’s blood have been correlated with a slew of physical and mental health metrics, including I.Q., Dr. Cory-Slechta said. “We have actual data on I.Q. scores in kids with different blood-lead concentrations.”

Using those modern-day relationships, Dr. McConnell and his team estimated that children across much of the Roman Empire would have had around 2 to 5 additional micrograms of lead, per deciliter of blood. Such levels correspond to I.Q. declines of roughly 2 or 3 points.

For comparison, American children in the 1970s had average blood-lead-level enhancements of around 15 micrograms more lead per deciliter of blood before the phasing out of leaded gasoline and leaded paints. Their corresponding average I.Q. decline was about 9 points.

But lead exposure would have had other negative effects on Romans as well. Higher levels of lead in the blood have also been linked to higher incidences of preterm births and reduced cognitive functioning in old age. “It follows you throughout life,” Dr. Lanphear said.

Some scholars have hypothesized that lead poisoning played an important role in the decline of the Roman Empire. But that idea has been called into question, at least when it comes to water contaminated by lead pipes. A 2014 study showed that, while the pipes used to distribute water in Rome increased lead levels, the water was unlikely to be truly harmful.

These new findings make sense, said Hugo Delile, a geoarchaeologist at the French National Centre for Scientific Research, who was not involved in the research. “They confirm the extent of lead pollution resulting from Roman mining and metallurgical activities.”

According to Dr. McConnell, the research also confers a dubious honor on Roman mining. “To my knowledge, it’s the earliest example of widespread industrial pollution,” he said.