U.S. Provincetown Outbreak Shows Delta Can Spread Among Vaccinated, But Cases Are Mild

Ernie Mundell and Robin Foster wrote . . . . . . . . .

The Cape Cod resort town of Provincetown draws big crowds every summer. In July, those largely vaccinated crowds — packed into bars, restaurants and private homes — were the genesis of an outbreak of the Delta variant that could be a sobering model for the nation.

New data on the outbreak, released Friday, shows there were a known total of 469 COVID-19 cases “associated with multiple summer events” among Provincetown revelers. Three-quarters (74%) of those cases occurred among people who’d gotten their COVID vaccinations an average of almost three months before.

In 89% of those cases, the highly contagious Delta variant was implicated, concluded a team led by Dr. Catherine Brown of the Massachusetts Department of Public Health.

There was some good news, however: While many of the 346 cases among vaccinated individuals might have made them feel miserable for a time — coughs, headache, sore throat, aches and fever being the major symptoms — there were only four cases (1.2%) in this group that required hospital care.

In all four of those hospitalized cases, patients had underlying medical conditions that upped their odds for severe COVID-19, the researchers found.

A fifth case requiring hospitalization occurred in an unvaccinated patient, Brown’s team noted, and that case also involved an underlying medical condition.

There were no deaths linked to the outbreak.

The researchers noted that it’s not surprising that three-quarters of cases in the Provincetown outbreak occurred among the vaccinated, because a full 69% of the town’s vaccine-eligible residents have gotten their shots — a number that’s much higher than the national average.

Equal viral loads

However, given the increased transmissibility of the Delta variant, Brown’s team believe their findings “suggest that even jurisdictions with substantial or high COVID-19 transmission might consider expanding prevention strategies.”

Those strategies should include “masking in indoor settings regardless of vaccination status, given the potential risk of infection during attendance at large public gatherings,” they said.

The Provincetown findings also confirm that, unlike its predecessor, the Delta variant appears to produce high viral loads in people’s systems, upping transmission risks.

“Specimens from 127 vaccinated persons with breakthrough cases were similar to those from 84 persons who were unvaccinated,” the research team noted.

That finding helped drive the CDC’s decision this week to reverse course on its masking advisory. The agency now recommends that even the vaccinated once again don masks in many indoor settings, to lessen the odds they might transmit SARS-CoV-2 to others.

It also adds new energy to federal, state and local efforts to get more Americans vaccinated.

However, one leading infectious disease expert stressed that the one thing the Provincetown report should not do is lessen the average American’s faith in the power of vaccines to protect against what’s most important: Severe illness.

“The new data should not alarm anyone, but reinforce that vaccinations are the solution to the pandemic,” said Dr. Amesh Adalja, a senior scholar at the Johns Hopkins Center for Health Security in Baltimore.

A return to masking indoors

“That severe breakthrough infections were rare is testament to the vaccines, which limit the harm an infection can do in a fully vaccinated person,” he said. “It’s also important to remember the breakthroughs that occurred in this situation are likely not completely applicable to the everyday life of the vaccinated, as the intensity and nature of exposure was in the context of a large public gathering.”

Another expert said the implications of the findings are clear.

“At this time, even fully vaccinated people need to consider large gatherings as a potential place to contract the virus,” said Dr. Teresa Murray Amato, chair of emergency medicine at Long Island Jewish Forest Hills, in Queens, N.Y. “This also means that for Americans that are not yet vaccinated,” they should strongly consider doing so.

Adding to the Provincetown findings, a new internal federal government document also finds the Delta variant can cause more severe illness than earlier coronavirus variants, especially among the unvaccinated, and spreads as easily as chickenpox.

In laying out the evidence that this variant looks like the most dangerous one yet, the document urges health officials to “acknowledge the war has changed,” the Washington Post reported.

The document mirrors the data in the Provincetown study, finding that vaccinated people infected with Delta have viral loads similar to those who are unvaccinated and infected with the variant, the Post reported.

CDC scientists were so alarmed that the agency changed masking guidance for vaccinated people earlier this week, even before making the new data public, the newspaper said.

CDC Director Dr. Rochelle Walensky said in a statement on Friday that the Provincetown investigation “is one of many CDC has been involved in across the country and data from those investigations will be rapidly shared with the public when available.”

The Provincetown study was published in the CDC journal Morbidity and Mortality Weekly Report.

Source: HealthDay

Two Types of Blood Pressure Meds Prevent Heart Events Equally, But Side Effects Differ

People who are just beginning treatment for high blood pressure can benefit equally from two different classes of medicine – angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) – yet ARBs may be less likely to cause medication side effects, according to an analysis of real-world data published today in Hypertension, an American Heart Association journal.

While the class of blood pressure-lowering medicines called angiotensin-converting enzyme (ACE) inhibitors may be prescribed more commonly, angiotensin receptor blockers (ARBs) work just as well and may cause fewer side effects. Currently, ACE inhibitors are prescribed more commonly than ARBs as a first-time blood pressure control medicine.

The findings are based on an analysis of eight electronic health record and insurance claim databases in the United States, Germany and South Korea that include almost 3 million patients taking a high blood pressure medication for the first time with no history of heart disease or stroke.

Both types of medicines work on the renin-angiotensin-aldosterone system, a group of related hormones that act together to regulate blood pressure. ACE inhibitors lower blood pressure by blocking an enzyme early in the system so that less angiotensin, a chemical that narrows blood vessels, is produced, and blood vessels can remain wider and more relaxed. ARBs block receptors in the blood vessels that angiotensin attaches to, diminishing its vessel-constricting effect.

“In professional guidelines, several classes of medications are equally recommended as first-line therapies. With so many medicines to choose from, we felt we could help provide some clarity and guidance to patients and health care professionals,” said RuiJun Chen, M.D., M.A., lead author of the study, assistant professor in translational data science and informatics at Geisinger Medical Center in Danville, Pennsylvania, and NLM postdoctoral fellow at Columbia University at the time of the study.

The AHA/ACC 2017 Guideline for the Prevention, Detection, Evaluation and Management of High Blood Pressure in Adults says the primary medications for treating high blood pressure are thiazide diuretics, ACE inhibitors, ARBs, and calcium channel blockers as they have been shown to reduce cardiovascular events. Physical activity and other lifestyle changes are recommended for managing all levels of high blood pressure, even if medication is required.

Health records for patients who began first-time blood pressure-lowering treatment with a single medicine between 1996-2018 were reviewed for this study. Researchers compared the occurrence of heart-related events and stroke among 2,297,881 patients treated with ACE inhibitors to those of 673,938 patients treated with ARBs. Heart-related events include heart attack, heart failure or stroke, or a combination of any of these events or sudden cardiac death recorded in the database. The researchers also compared the occurrence of 51 different side effects between the two groups. Follow-up times varied in the database records, but they ranged from about 4 months to more than 18 months.

They found no significant differences in the occurrence of heart attack, stroke, hospitalization for heart failure, or any cardiac event. However, they found significant differences in the occurrence of four medication side effects. Compared with those taking ARBs, people taking ACE inhibitors were:

  • 3.3 times more likely to develop fluid accumulation and swelling of the deeper layers of the skin and mucous membranes (angioedema);
  • 32% more likely to develop a cough (which may be dry, persistent, and bothersome);
  • 32% more likely to develop sudden inflammation of the pancreas (pancreatitis); and
  • 18% more likely to develop bleeding in the gastrointestinal tract;

“We did not detect a difference in how the two types of medicine reduced the complications of hypertension, but we did see a difference in side effects,” said George Hripcsak, M.D., senior author of the study and professor and chair of biomedical informatics at Columbia University Vagelos College of Physicians and Surgeons and medical informatics services director at New York-Presbyterian/Columbia University Irving Medical Center. “If a patient is starting hypertension therapy for the first time, our results point to starting with the ARB over the ACE inhibitor.”

“ARBs do not differ in effectiveness and may have fewer side effects than ACE inhibitors among those just beginning treatment,” said Chen. “We unfortunately cannot extend these conclusions to people who are already taking ACE inhibitors or those who are taking multiple medications. We would reiterate that if you experience any side effects from your medicine, you should discuss with your doctor whether your antihypertensive regimen may need to be adjusted.”

The study is limited by wide variation in the length of time patients were included in the different databases. Although many people were followed for a long period of time, those who had shorter follow-up periods may not have taken the medications long enough to experience their full benefits in preventing cardiovascular disease events. Most of the participants taking ACE inhibitors (80%) were taking lisinopril, and the most used ARB (45% of those taking this class of medication) was losartan, so the results may not be fully generalizable to other medicines in these classes. It is also important to note that results from this analysis of first-line therapy may not be generalizable to people with hypertension who have been prescribed combination treatment or who switch from one type of medication to another.

“In addition to encouraging patients to live a healthy lifestyle and taking medication as prescribed to control blood pressure, the American Heart Association recommends regular self-blood pressure monitoring with a validated device and working with a health care professional on a plan to reduce blood pressure,” said Willie Lawrence, M.D., interventional cardiologist and medical director for Health Equity, Spectrum Health, Benton Harbor, Michigan and head of the American Heart Association’s National Hypertension Control Initiative Oversight Committee.

Source: American Heart Association

Swimming Gives Your Brain a Boost – But Scientists Don’t Know Yet Why It’s Better than Other Aerobic Activities

Seena Mathew wrote . . . . . . . . .

It’s no secret that aerobic exercise can help stave off some of the ravages of aging. But a growing body of research suggests that swimming might provide a unique boost to brain health.

Regular swimming has been shown to improve memory, cognitive function, immune response and mood. Swimming may also help repair damage from stress and forge new neural connections in the brain.

But scientists are still trying to unravel how and why swimming, in particular, produces these brain-enhancing effects.

As a neurobiologist trained in brain physiology, a fitness enthusiast and a mom, I spend hours at the local pool during the summer. It’s not unusual to see children gleefully splashing and swimming while their parents sunbathe at a distance – and I’ve been one of those parents observing from the poolside plenty of times. But if more adults recognized the cognitive and mental health benefits of swimming, they might be more inclined to jump in the pool alongside their kids.

Until the 1960s, scientists believed that the number of neurons and synaptic connections in the human brain were finite and that, once damaged, these brain cells could not be replaced. But that idea was debunked as researchers began to see ample evidence for the birth of neurons, or neurogenesis, in adult brains of humans and other animals.

Now, there is clear evidence that aerobic exercise can contribute to neurogenesis and play a key role in helping to reverse or repair damage to neurons and their connections in both mammals and fish.

Research shows that one of the key ways these changes occur in response to exercise is through increased levels of a protein called brain-derived neurotrophic factor. The neural plasticity, or ability of the brain to change, that this protein stimulates has been shown to boost cognitive function, including learning and memory.

Studies in people have found a strong relationship between concentrations of brain-derived neurotrophic factor circulating in the brain and an increase in the size of the hippocampus, the brain region responsible for learning and memory. Increased levels of brain-derived neurotrophic factor have also been shown to sharpen cognitive performance and to help reduce anxiety and depression. In contrast, researchers have observed mood disorders in patients with lower concentrations of brain-derived neurotrophic factor.

Aerobic exercise also promotes the release of specific chemical messengers called neurotransmitters. One of these is serotonin, which – when present at increased levels – is known to reduce depression and anxiety and improve mood.

In studies in fish, scientists have observed changes in genes responsible for increasing brain-derived neurotrophic factor levels as well as enhanced development of the dendritic spines – protrusions on the dendrites, or elongated portions of nerve cells – after eight weeks of exercise compared with controls. This complements studies in mammals where brain-derived neurotrophic factor is known to increase neuronal spine density. These changes have been shown to contribute to improved memory, mood and enhanced cognition in mammals. The greater spine density helps neurons build new connections and send more signals to other nerve cells. With the repetition of signals, connections can become stronger.

But what’s special about swimming?

Researchers don’t yet know what swimming’s secret sauce might be. But they’re getting closer to understanding it.

Swimming has long been recognized for its cardiovascular benefits. Because swimming involves all of the major muscle groups, the heart has to work hard, which increases blood flow throughout the body. This leads to the creation of new blood vessels, a process called angiogenesis. The greater blood flow can also lead to a large release of endorphins – hormones that act as a natural pain reducer throughout the body. This surge brings about the sense of euphoria that often follows exercise.

Research in people suggest a clear cognitive benefit from swimming across all ages. For instance, in one study looking at the impact of swimming on mental acuity in the elderly, researchers concluded that swimmers had improved mental speed and attention compared with nonswimmers. However, this study is limited in its research design, since participants were not randomized and thus those who were swimmers prior to the study may have had an unfair edge.

Another study compared cognition between land-based athletes and swimmers in the young adult age range. While water immersion itself did not make a difference, the researchers found that 20 minutes of moderate-intensity breaststroke swimming improved cognitive function in both groups.

Kids get a boost from swimming too

The brain-enhancing benefits from swimming appear to also boost learning in children.

Another research group recently looked at the link between physical activity and how children learn new vocabulary words. Researchers taught children age 6-12 the names of unfamiliar objects. Then they tested their accuracy at recognizing those words after doing three activities: coloring (resting activity), swimming (aerobic activity) and a CrossFit-like exercise (anaerobic activity) for three minutes.

They found that children’s accuracy was much higher for words learned following swimming compared with coloring and CrossFit, which resulted in the same level of recall. This shows a clear cognitive benefit from swimming versus anaerobic exercise, though the study does not compare swimming with other aerobic exercises. These findings imply that swimming for even short periods of time is highly beneficial to young, developing brains.

The details of the time or laps required, the style of swim and what cognitive adaptations and pathways are activated by swimming are still being worked out. But neuroscientists are getting much closer to putting all the clues together.

For centuries, people have been in search of a fountain of youth. Swimming just might be the closest we can get.

Source: Conversation

Global COVID-19 Cases Are Rising Again

Data of 220 countries and territories as of July 29, 2021

Source: Worldometers

Want to Avoid Sleep Apnea? Get Off the Sofa

Here’s yet another reason to limit screen time and get moving: Boosting your activity levels could reduce your risk of sleep apnea, according to a new study.

Compared to the most active people in the study, those who spent more than four hours a day sitting watching TV had a 78% higher risk of obstructive sleep apnea (OSA), and those with sedentary jobs had a 49% higher risk.

And that added risk was not due to their weight.

“We saw a clear relationship between levels of physical activity, sedentary behavior and OSA risk. People who followed the current World Health Organization physical activity guidelines of getting at least 150 minutes of moderate activity per week, and who spent less than four hours per day sitting watching TV, had substantially lower OSA risk,” said study leader Tianyi Huang, an assistant professor and associate epidemiologist at Brigham and Women’s Hospital and Harvard Medical School, in Boston.

People with this disorder stop and start breathing many times during sleep. Common symptoms include snoring, disrupted sleep and excessive tiredness. Poorly managed sleep apnea can increase the risk of high blood pressure, stroke, heart attack, irregular heartbeat and type 2 diabetes.

After accounting for risk factors such as obesity, age, smoking and drinking, the researchers found that people whose activity levels were equivalent to three hours of running a week had a 54% lower risk of sleep apnea than those whose activity levels were equivalent to two hours a week of walking at an average pace.

The study included more than 138,000 U.S. women and men without a diagnosis of sleep apnea. They were followed for 10 to 18 years. Over that time, more than 8,700 were diagnosed with the condition.

So are desk jockeys doomed? Not necessarily.

The researchers said folks with sedentary jobs could lower their risk by getting more exercise in their leisure time. Also, those who can’t do much physical activity due to physical limitations could lower their risk of sleep apnea by standing or doing other gentle activities more often.

The study was published in the European Respiratory Journal.

“Importantly, we saw that any additional increase in physical activity, and/or a reduction in sedentary hours, could have benefits that reduce the risk of developing OSA,” Huang explained in a journal news release.

The difference in risk between sedentary work and time spent sitting watching TV could be explained by other behaviors related to those activities, the researchers suggested.

“For example, snacking and drinking sugary drinks is more likely to go along with watching TV compared with being sedentary at work or elsewhere, such as sitting during traveling. This could lead to additional weight gain, which we know to be a risk factor for OSA,” Huang noted.

It’s estimated that 1 billion adults worldwide, aged 30 to 69, have mild to severe sleep apnea.

Anita Simonds, president of the European Respiratory Society, was not involved with the study but commented on the report. She said, “It is encouraging that even a small increase in physical activity or reduction in sedentary hours could reap potential benefits. It is therefore an important message to get across to our patients and their families in primary care and respiratory clinics.”

Source: HealthDay