Fast Walking in Narrow Corridors Can Increase COVID-19 Transmission Risk - راه رفتن سریع در راهروهای باریک می تواند سبب افزایش سرایت ویروس کرونا گردد

Computational simulations have been used to accurately predict airflow and droplet dispersal patterns in situations where COVID-19 might be spread. In the journal Physics of Fluids, by AIP Publishing, results show the importance of the shape of the space in modeling how virus-laden droplets move through the air.

The cough-generated droplets from a walking individual disperse differently in a narrow corridor and an open space. In an open space, the droplets are dispersed in a large range attached to the person; in narrow corridors, the droplets are concentrated in a small bubble and are left further behind. CREDIT: Xiaolei Yang

If a person walking in a corridor coughs, their breath expels droplets that travel around and behind their body, forming a wake in the way a boat forms a wake in water as it travels. The investigation revealed the existence of a “re-circulation bubble” directly behind the person’s torso and a long wake streaming out behind them at approximately waist height.

Release date: 15 December 2020
Source: American Institute of Physics

Coronavirus spread during dental procedures could be reduced with slower drills - استفاده از ابزارهای مناسب حین اقدامات دندانپزشکی می تواند به کاهش انتشار ویروس کرونا کمک کند

Dental procedures can pose a high risk of viral transmission because the tools that are used often produce aerosols, which can contain high numbers of Coronavirus.

The aerosols are generated when saliva mixes with water and air streams used in dental procedures. As a result, access to routine dentistry continues to be limited during the current COVID-19 pandemic.

They found that using air turbine drill types, which are the most common type of dental drill, creates dense clouds of aerosol droplets that spread as fast as 12 metres per second and can quickly contaminate an entire treatment room. Just one milliliter of saliva from infected patients contains up to 120 million copies of the virus, each having the capacity to infect.

They tested a different type of drill, known as high torque electric micromotor, with and without the use of water and air streams. They found that using this drill type at low speeds of less than 100,000 rpm without air streams produced 60 times fewer droplets than air turbine drill types.

In addition, they found that aerosol concentration and spread within a room is dependent on the positioning of the patient, presence of ventilation systems, and the room’s size and geometry. It is also influenced by the initial direction and speed of the aerosol itself, which can be affected by the type of cutting instrument (burr), and the amount and type of cooling water used.

Release date: 17 December 2020
Source: Imperial College London

Business closures partial reopenings due to COVID may cost the US in GDP - تعطیلی های کرونا برای تولید ناخالص ایالات متحده هزینه دارد

Among highlights of the study, the researchers projected:

  • 54 million to 367 million work days would be lost due to people getting sick or die from COVID.
  • 2 million to nearly 15 million work days would be lost due to employees staying home to care for sick loved ones.
  • Job losses could range from 14.7% to 23.8%, and in the worst case affect an estimated 36.5 million workers.
  • Demand for health care has risen with COVID infections. Medical expenses due to COVID-19 from March 2020 to February 2022 could range from nearly $32 billion to $216 billion.
  • A loss in demand for some services — such as the use of public transit and school attendance, restaurant dining and travel — as people avoid public places and services to reduce their risk of exposure.
  • An uptick in demand for communication services, as many employees during this pandemic have had to work from home.
  • An increase in pent-up demand since consumers are unable to spend money on big-ticket items such as cars, as well as travel, restaurants, hotels, merchandise, fitness, sporting events and concerts during the closures, and, to a lesser extent, during the phased reopenings.

Economics of Disasters and Climate Change

Release date: 30 November 2020
Source: University of Southern California

SARS-CoV-2 mutations do not appear to increase transmissibility - به نظر نمی رسد جهش های ژنی کرونا باعث افزایش سرایت پذیری ویروس گردد

None of the mutations currently documented in the SARS-CoV-2 virus appear to increase its transmissibility, according to a UCL-led study.

The analysis of virus genomes from over 15,000 Covid-19 patients from 75 countries is published today as a pre-print on bioRxiv and has not yet been peer-reviewed.

The findings build on a peer-reviewed study published in Infection, Genetics and Evolution earlier this month that characterised patterns of diversity emerging in the genome of SARS-CoV-2, the coronavirus causing the ongoing pandemic of the Covid-19 disease. Nature Communications 

Release date: 22 November 2020
Source: University College London

COVID-19 affects the eyes - کرونا می تواند باعث ایجاد زخم در چشم گردد

The study found that sore eyes was significantly more common when the participants had COVID-19, with 16% reporting the issue as one of their symptoms. Just 5% reported having had the condition beforehand.

While 18% of people reported suffering from photophobia (light sensitivity) as one of their symptoms, this was only a 5% increase from their pre-COVID-19 state.

Of the 83 respondents, 81% reported ocular issues within two weeks of other COVID-19 symptoms. Of those, 80% reported their eye problems lasted less than two weeks.

The most common reported symptoms overall were fatigue (suffered by 90% of respondents), a fever (76%) and a dry cough (66%).

Release date: 08 December 2020
Source: Anglia Ruskin University

Significant increase in depression seen among children during first lockdown - افزایش قابل توجه افسردگی در کودکان به دنبال قرنطینه

The first lockdown led to a significant increase in symptoms of depression among children, highlighting the unintended consequences of school closures, according to a new study from the University of Cambridge.

In response to the COVID-19 pandemic, the UK Government implemented a national ‘lockdown’ involving school closures and social distancing. There has been widespread concern that these measures would negatively impact child and adolescent mental health. To date, however, there is relatively little direct evidence of this.

To test whether changes in emotional wellbeing, anxiety and depression symptoms occurred during lockdown since their initial assessment, a team at the Medical Research Council (MRC) Cognition and Brain Sciences Unit, University of Cambridge, examined data from mental health assessments on 168 children (aged 8-12 years) before and during the UK lockdown. These assessments included self-reports, caregiver-reports, and teacher-reports.

“Put differently, if you randomly selected a child from the sample there is a 70% chance that their depression symptoms were worse during lockdown than before the pandemic.”

The results of their study are published in Archives of Disease in Childhood.

Release date: 08 December 2020
Source: University of Cambridge

COVID-19 persistent symptoms in one third of cases - کووید19 باقی ماندن علایم در یک سوم مبتلایان

A total of 669 people were followed (mean age 43 years, 60% female, 25% of healthcare professionals and 69% without underlying risk factors that could be related to complications from COVID-19). At 6 weeks from diagnosis, nearly a third of participants still had one or more symptoms related to COVID-19, mainly fatigue (14%), shortness of breath (9%) and loss of taste or smell (12%). In addition, 6% reported a persistent cough and 3% reported headaches. Dr. Mayssam Nehme, Senior Resident in Professor Guessous’s team and first author of this work, also explains how these patients felt: “In addition to the physical distress of their symptoms, many were very worried: how much longer would it last? Were some after-effects irrecoverable? Even without a clear medical answer, in the current state of knowledge, it is important to accompany concerned patients and to listen to them,” she adds. With this in mind, the HUG has set up a specific consultation for long COVID patients in order to improve their care and guide them through the health system.

These results, which can be seen in the Annals of Internal Medicine, call for better communication, particularly with patients and with the physicians who follow them, and for ongoing messages to the general public, reminding them that SARS-CoV-2infection is not trivial.

Release date: 08 December 2020
Source: Université de Genève

Elevated Biomarker Related to Blood Vessel Damage in All Children with SARS CoV 2 - مارکر نشان دهنده آسیب عروقی در همه کودکان مبتلا به کرونا افزایش میابد

Researchers at Children’s Hospital of Philadelphia (CHOP) have found elevated levels of a biomarker related to blood vessel damage in children with SARS-CoV-2 infection, even if the children had minimal or no symptoms of COVID-19. They also found that a high proportion of children with SARS-CoV-2 infection met clinical and diagnostic criteria for thrombotic microangiopathy (TMA). TMA is a syndrome that involves clotting in the small blood vessels and has been identified as a potential cause for severe manifestations of COVID-19 in adults.

To assess the role of complement activation in children with SARS-CoV-2, the Immune Dysregulation Frontier Program, including co-senior authors Edward Behrens, MD and Hamid Bassiri, MD, PhD and co-first authors Caroline Diorio, MD and Kevin McNerney, MD, analyzed 50 pediatric patients hospitalized at CHOP with acute SARS-CoV-2 infection between April and July 2020. Of those 50 patients, 21 had minimal COVID-19, 11 had severe COVID-19, and 18 were diagnosed with MIS-C. The researchers used soluble C5b9 (sC5b9) as a biomarker for complement activation and TMA. sC5b9 has been implicated as an indicator of severity in TMA after hematopoietic stem cell transplant; transplant patients with markedly elevated sC5b9 have increased mortality.

The findings were published in Blood Advances.

Release date: 08 December 2020
Source: Children’s Hospital of Philadelphia

COVID-19 May Deepen Depression Anxiety and PTSD Among Pregnant and Postpartum Women - همه گیری کرونا مشکلات روانپزشکی دوران بارداری و پس از آن را تشدید کرده است

In a new study published in Psychiatry Research, researchers from Brigham and Women’s Hospital surveyed pregnant women and those who had recently given birth, finding concerning rates of depression, generalized anxiety and post-traumatic stress disorder (PTSD) symptoms, which were found to be exacerbated by COVID-19-related grief and health worries. The researchers launched the Perinatal Experiences and COVID-19 Effects Study (PEACE) to better understand the mental health and well-being of pregnant and postpartum individuals within the U.S. during the COVID-19 pandemic. Among 1,123 of these women surveyed between May 21 and August 17, 2020, the researchers found that more than 1-in-3 (36.4 percent) reported clinically significant levels of depression. Before the pandemic, rates of perinatal depression (depression occurring during or after pregnancy) were generally considered to be 15-20 percent. Furthermore, 1-in-5 (22.7 percent) reported clinically significant levels of generalized anxiety, and 1-in-10 (10.3 percent) reported symptoms above the clinical threshold for PTSD.


Release date: 01 December 2020
Source: Brigham and Women’s Hospital

More than one-third of children with COVID-19 show no symptoms - بیش از یک سوم کودکان مبتلا به کووید19 هیچ علامتی ندارند

More than one-third of kids who have COVID-19 are asymptomatic, according to a University of Alberta study that suggests youngsters diagnosed with the disease may represent just a fraction of those infected.

For the study, McAlister’s team analyzed results for 2,463 children who were tested during the first wave of the pandemic—March to September—for COVID-19 infection.

All told, 1,987 children had a positive test result for COVID-19 and 476 had a negative result. Of children who tested positive, 714—35.9 per cent—reported being asymptomatic.

We can do all the COVID-19 questionnaires we want, but if one-third of the kids are asymptomatic, the answer is going to be no to all the questions—yet they’re still infected.

Because of the asymptomatic nature of the disease in up to one-third of children, McAlister said the province was right to close schools for a longer period over Christmas.

As far as we know, kids are less likely to spread disease than adults, but the risk is not zero. Presumably asymptomatic spreaders are less contagious than the person sitting nearby who is sneezing all over you, but we don’t know that for sure.

The researchers also found that although cough, runny nose and sore throat were three of the most common symptoms among children with COVID-19 infection—showing up in 25, 19 and 16 per cent of cases respectively—they were actually slightly more common among those with negative COVID-19 test results, and therefore not predictive of a positive test.

Kids are at risk of contracting many different viruses, so the COVID-specific symptoms are actually more things like loss of taste and smell, headache, fever, and nausea and vomiting, not runny nose, a cough and sore throat.

Release date: 27 November 2020
Source: University of Alberta Faculty of Medicine & Dentistry