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Alzheimers and Covid-19 share a genetic risk factor - کرونا و آلزایمر

An anti-viral gene that impacts the risk of both Alzheimer’s disease and severe Covid-19 has been identified by a UCL-led research team.

The researchers estimate that one genetic variant of the OAS1 gene increases the risk of Alzheimer’s disease by about 3-6% in the population as a whole, while related variants on the same gene increase the likelihood of severe Covid-19 outcomes.

The findings, published in Brain, could open the door for new targets for drug development or tracking disease progression in either disease, and suggest that treatments developed could be used for both conditions. The findings also have potential benefits for other related infectious conditions and dementias.

Release date: 08 October 2021
Source: University College London

COVID-19 Coughing without masks distancing alone is not enough - فاصله گذاری بدون ماسک کم اثر

To prevent the spread of COVID-19 indoors, the two metres physical distancing guideline is not enough without masks, according to researchers from Quebec, Illinois, and Texas. However, wearing a mask indoors can reduce the contamination range of airborne particles by about 67 percent.

“Mask mandates and good ventilation are critically important to curb the spread of more contagious strains of COVID-19, especially during the flu season and winter months as more people socialize indoors,” says Saad Akhtar, a former doctoral student under the supervision of Professor Agus Sasmito at McGill University.

While most public health guidelines recommend physical distancing of two metres for people from different households, the researchers say distancing alone is not enough to prevent the spread of COVID-19. In a study published in Building and Environment, the researchers found that when people are unmasked, more than 70 percent of airborne particles pass the two metres threshold within the 30 seconds. By contrast, less than 1 percent of particles cross the two-metre mark if masks are worn.

Release date: 05 October 2021
Source: McGill University

Those under 40 more likely than older adults to recover COVID-related smell and taste loss - بویایی و کرونا

Ongoing survey tracking smell and taste recovery of COVID-19 survivors shows 4 out of every 5 recover senses within 6 months.

RICHMOND, Va. (October 5, 2021) — Sense of smell or taste returns within six months for 4 out of every 5 COVID-19 survivors who have lost these senses, and those under 40 are more likely to recover these senses than older adults, an ongoing Virginia Commonwealth University study found.

Among 798 respondents to the ongoing COVID-19 smell and taste loss survey who had tested positive for COVID-19 and reported a loss of smell or taste, participants who were younger than 40 recovered their sense of smell at a higher rate than those older than 40, according to study results published in the American Journal of Otolaryngology last month. The VCU study requires survey participants to be 18 years or older.

What symptoms COVID-19 survivors experienced and what pre-existing conditions they had also offered insights into their recovery. Those with a history of head injury were less likely to recover their sense of smell. Recovery was also less likely for those who had shortness of breath during COVID-19. However, those with nasal congestion had a higher likelihood of smell recovery.

Release date: 05 October 2021
Source: Virginia Commonwealth University

COVID19 has caused the biggest decrease in life expectancy since World War II - بیشترین کاهش امید به زندگی بعد از جنگ جهانی دوم

The research team assembled an unprecedented dataset on mortality from 29 countries, spanning most of Europe, the US and Chile – countries for which official death registrations for 2020 had been published. They found that 27 of the 29 countries saw reductions in life expectancy in 2020, and at a scale which wiped out years of progress on mortality, according to the paper published today in the International Journal of Epidemiology.

Women in 15 countries and men in 10 countries were found to have a lower expectancy at birth in 2020 than in 2015, a year in which life expectancy was already negatively affected by a significant flu season.

According to the study’s co-lead author Dr José Manuel Aburto, ‘For Western European countries such as Spain, England and Wales, Italy, Belgium, among others, the last time such large magnitudes of declines in life expectancy at birth were observed in a single year was during WW-II.

But, he says, the scale of the life expectancy losses was stark across most countries studied, ‘Twenty two countries included in our study experienced larger losses than half a year in 2020. Females in eight countries and males in 11 countries experienced losses larger than a year. To contextualize, it took on average 5.6 years for these countries to achieve a one-year increase in life expectancy recently: progress wiped out over the course of 2020 by COVID-19.’

Release date: 27 September 2021
Source: University of Oxford

Poorly Circulated Room Air Raises Potential Exposure to Contaminants by up to 6 Times - اهمیت تهویه در کنترل سرایت کرونا

Berkeley Lab experiments quantify the effects of overhead heating on room air mixing with implications for COVID-safe meetings and classrooms. Having good room ventilation to dilute and disperse indoor air pollutants has long been recognized, and with the COVID-19 pandemic its importance has become all the more heightened. But new experiments by indoor air researchers at Lawrence Berkeley National Laboratory (Berkeley Lab) show that certain circumstances will result in poor mixing of room air, meaning airborne contaminants may not be effectively dispersed and removed by building level ventilation.

Using CO2 as a tracer to track small respiratory aerosols that travel with air currents in a room, the Berkeley Lab team found that when overhead vents (or diffusers) are supplying heated air, it created thermally stratified conditions that block the flow of clean air down to the “breathing zone” in the middle height of the room. As a result, even when people are sitting more than 6 feet from each other, some occupants may be exposed to respiratory aerosols from others at a rate 5 to 6 times higher than if the same room were well mixed.

Their study, “Measured influence of overhead HVAC on exposure to airborne contaminants from simulated speaking in a meeting and a classroom,” was published recently in the journal Indoor Air.

Release date: 22 September 2021
Source: DOE/Lawrence Berkeley National Laboratory

COVID19 Nasal Vaccine Candidate Effective At Preventing Disease Transmission - واکسن تنفسی کرونا

IN THROUGH THE NOSE…

Breathe in, breathe out. That’s how easy it is for SARS-CoV-2, the virus that causes COVID-19, to enter your nose. And though remarkable progress has been made in developing intramuscular vaccines against SARS-CoV- 2, such as the readily available Pfizer, Moderna and Johnson & Johnson vaccines, nothing yet – like a nasal vaccine – has been approved to provide mucosal immunity in the nose, the first barrier against the virus before it travels down to the lungs. But now, we’re one step closer.

Navin Varadarajan, M.D. Anderson Professor of Chemical and Biomolecular Engineering at the Cullen College of Engineering, and his colleagues are reporting in iScience the development of an intranasal subunit vaccine that provides durable local immunity against inhaled pathogens.

Release date: 15 September 2021
Source: University of Houston

Physical distance may not be enough to prevent viral aerosol exposure indoors- فقط فاصله گذاری کافی نیست

Eighteen months ago, stickers began to dot the floors of most shops, spaced about six feet apart, indicating the physical distance required to avoid the COVID-19 virus an infected person may shed when breathing or speaking. But is the distance enough to help avoid infectious aerosols?

Not indoors, say researchers in the Penn State Department of Architectural Engineering. The team found that indoor distances of two meters — about six and a half feet — may not be enough to sufficiently prevent transmission of airborne aerosols. Their results were made available online print edition of Sustainable Cities and Society.

The researchers examined three factors: the amount and rate of air ventilated through a space, the indoor airflow pattern associated with different ventilation strategies and the aerosol emission mode of breathing versus talking. They also compared transport of tracer gas, typically employed to test leaks in air-tight systems, and human respiratory aerosols ranging in size from one to 10 micrometers. Aerosols in this range can carry SARS-CoV-2.

Release date: 16 September 2021
Source: Penn State

Diet may affect risk and severity of COVID19 - تغذیه مناسب در ایام کرونا

A healthy plant-based diet was linked to a lower risk of getting COVID-19, and among people with COVID-19, a lower risk of experiencing severe symptoms. There was a synergistic relationship between poor diet and increased socioeconomic deprivation with COVID-19 risk that was higher than the sum of the risk associated with each factor alone.

Although metabolic conditions such as obesity and type 2 diabetes have been linked to an increased risk of COVID-19, as well as an increased risk of experiencing serious symptoms once infected, the impact of diet on these risks is unknown. In a recent study led by researchers at Massachusetts General Hospital (MGH) and published in Gut, people whose diets were based on healthy plant-based foods had lower risks on both counts. The beneficial effects of diet on COVID-19 risk seemed especially relevant in individuals living in areas of high socioeconomic deprivation.

For the study, Merino and his colleagues examined data on 592,571 participants of the smartphone-based COVID-19 Symptom Study. Participants lived in the UK and the US, and they were recruited from March 24, 2020 and followed until December 2, 2020. At the start of the study, participants completed a questionnaire that asked about their dietary habits before the pandemic. Diet quality was assessed using a healthful Plant-BasedDiet Score that emphasises healthy plant foods such as fruits and vegetables.

During follow-up, 31,831 participants developed COVID-19. Compared with individuals in the lowest quartile of the diet score, those in the highest quartile had a 9% lower risk of developing COVID-19 and a 41% lower risk of developing severe COVID-19.

Release date: 08 September 2021
Source: Massachusetts General Hospital

Double vaccination halves risk of Long COVID - واکسیناسیون و سندرم پس از کرونا

The study, published in The Lancet Infectious Diseases, found that in the unlikely event of catching COVID-19 after being double vaccinated, the risk of Long COVID was reduced by almost half. There were also fewer hospitalisations (73% less likely) and lower burden of acute symptoms (31% less likely) among those fully vaccinated. The nature of the most common symptoms were similar to unvaccinated adults – e.g. anosmia,(loss of smell) cough, fever, headaches, and fatigue. All these symptoms were milder and less frequently reported by people who were vaccinated, and they were half as likely to get multiple symptoms in the first week of illness. Sneezing was the only symptom which was more commonly reported in vaccinated people with COVID-19.

However, people living in most deprived areas were at greater risk of infection after a single vaccination. While age on its own was not a risk factor, individuals who had health conditions that limited their independence – such as frailty – were up to two times more likely to contract COVID-19 infection after vaccination, and of getting sick.

The findings demonstrate the need to target at-risk groups. Frail adults have already been shown to be disproportionately affected by COVID-19. The research team suggests strategies such as a timely booster programme, targeted infection control measures and more research into the immune response to vaccination in this group could help address the issue.

Release date: 01 September 2021
Source: King’s College London

Prior exposure to common cold coronaviruses enhances immune response to SARS-CoV-2 - سرماخوردگی قبلی و محافظت کوویدی

Researchers from Charité – Universitätsmedizin Berlin, the Berlin Institute of Health at Charité (BIH) and the Max Planck Institute for Molecular Genetics (MPIMG) have shown that certain immune cells, which are found in people previously exposed to common cold coronaviruses, enhance the body’s immune response to SARS-CoV-2, both during natural infection and following vaccination. The researchers, whose work has been published in Science, also report that this ‘cross-reactive immunity’ decreases with age. This phenomenon may help to explain why older people are more susceptible to severe disease and why their vaccine-induced immunity is often weaker than that of young people.

Last year, researchers from Charité and the MPIMG made a surprising discovery. They were the first to report that individuals with no prior exposure to SARS-CoV-2 nonetheless had immunological memory cells capable of recognizing this novel virus. The researchers concluded that these ‘T helper cells’ must have been generated to deal with mostly harmless common cold coronaviruses and that, thanks to the structural similarities between coronaviruses (in particular the characteristic spike protein found on their outer surface), these T helper cells will also attack the novel coronavirus. This ‘cross reactivity’ hypothesis has since been confirmed by a range of studies.

Release date: 31 August 2021
Source: Charité – Universitätsmedizin Berlin