By Nancy Lapid

Here is a roundup of some of the latest scientific studies on the novel coronavirus and efforts to find treatments and vaccines for COVID-19, the illness caused by the virus.

Smell test might improve COVID-19 screening

A "smell test" might be a better way to screen for the novel coronavirus than checking for cough or fever, a new study suggests. COVID-19 patients often lose their sense of smell without realizing it, but researchers were able to use simple scratch-and-sniff cards to correctly identify 75% of infected individuals and 95% of people without the disease. In the study, 163 adults - who were being screened for COVID-19 with gold-standard PCR analysis of nasal swabs - were each given a card with scratch-and-sniff scents that they had to identify from a multiple-choice selection. "Compared to other symptoms like cough, fever, fatigue, and history of COVID-19 exposure, failing the smell card was the best predictor of COVID-19 positivity," Dr. Mena Said of the University of California, San Diego told Reuters. Quick smell tests might be a practical way to reduce COVID-19 transmission, he added, if larger studies with more diverse populations confirm these findings, which were reported on Thursday in JAMA Otolaryngology

Good vaccine responses seen in patients with solid tumors

The Pfizer-BioNTech COVID-19 vaccine appears to work well in patients receiving cancer treatments, according to a study from Israel. While there was a "pronounced" lag in antibody production in the cancer patients compared with non-cancer study subjects, most patients caught up after the second dose, researchers reported in JAMA Oncology https://bit.ly/3hqTIbB. They studied 232 patients with solid tumors receiving various treatments - such as chemotherapy, biological agents, or immunotherapy, or some combination - and 261 healthy people of similar ages. After the first dose of vaccine, 29% of cancer patients were producing antibodies, compared with 84% of controls. But after the second dose, cancer patients' rate reached 86%. Side effects were similar to those in trials of healthy individuals, and none of the cancer patients has developed a case of COVID-19, the researchers said. They added that cancer patients' second dose should be given according to the schedule recommended by the manufacturer, even in regions where the usual policy is to delay the second dose due to vaccine shortages.

COVID-19 complications impair life after hospital discharge

Nearly 50% of adults hospitalized with COVID-19 develop complications, and often these problems affect their ability to care for themselves after discharge, new research indicates. Men and those older than 50 were most likely to develop complications, but younger, previously healthy adults were not spared, researchers reported on Thursday in The Lancet https://bit.ly/3ikvgbi. "This work contradicts current narratives that COVID-19 is only dangerous in people with existing comorbidities and the elderly," coauthor Dr. Calum Semple of the University of Liverpool said in a news release. His team studied 73,197 adults hospitalized with COVID-19 across the UK in 2020. Overall, 49.7% suffered at least one complication, affecting the kidneys in 24%, breathing in 18%, multiple organs in 16%, the heart in 12%, the gastrointestinal system in 11%, and the nervous system in 4%. Complications occurred in 39% of individuals ages 19 to 49, compared to 51% of those over age 50. Rates were highest in Black patients. After leaving the hospital, more than one in four patients were less able to care for themselves than before they got sick. "Just focusing on death from COVID-19 is likely to underestimate the true impact, particularly in younger people who are more likely to survive severe COVID-19," coauthor Dr. Aya Riad of the University of Edinburgh said in the news release.

Emergency departments seeing more mask-related injuries

The spike in face mask use during the pandemic came with a spike in mask-related injuries, a new study shows. From 2016 through 2019, an average of 200 such injuries were treated annually in U.S. emergency departments. In 2020, that number went up by 2,400%, to nearly 5,000, according to data published on Friday. The injuries occurred at all ages, with white and Black people equally represented, researchers reported in the Journal of the American Academy of Dermatology. Most common were skin irritation, rashes, and allergic reactions. But 14% of mask-related injuries were due to obscured vision and included falls and motor vehicle accidents. Five percent were in children who had eaten a piece of a mask or stuck a piece into the nose or other orifice. Three percent of injuries, all in elderly people, were due to falls from bending over to pick up a dropped mask. "The Centers for Disease Control and Prevention has published recommendations and resources to aid in the choice and proper fit of face masks," the study authors wrote. "The results of the current study underscore the need for increased awareness of these resources in order to minimize the future occurrence of mask-related injuries."