Asthma patients less likely to die from virus; new test better at telling who is still infectious | Reuters
The following 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.
Asthma patients appear less likely to die from COVID-19
Patients with asthma who become infected with the new coronavirus appear to have no higher risk of hospitalization or need for mechanical breathing assistance compared to COVID-19 patients without asthma – and the asthma patients are less likely to die from the disease, a new study suggests. Researchers at a Boston healthcare system studied 562 asthma patients with COVID-19 and 2,686 similarly-aged COVID-19 patients without asthma. The two groups were hospitalized at similar rates (18% to 21%) and had similar need for mechanical ventilation (3% in the asthma group vs 4%). But the asthma patients were 70% less likely to die from the virus, researchers reported. None of the 44 patients with severe asthma died. “Although the factors underlying these findings are not yet known, important considerations include: possible biologic mechanisms … and possible protective effects of asthma medications (such as corticosteroids),” the researchers said in a report posted on Monday on medRxiv ahead of peer review. (bit.ly/3iAgxXD)
New test better at identifying who is still infectious
Becton Dickenson and Co’s BD Veritor System for rapid detection of the novel coronavirus is better than gold standard RT-PCR lab tests at distinguishing between infectious and non-infectious virus in swab samples obtained within a week of symptom onset, according to a new study. One drawback of the RT-PCR (real-time polymerase chain reaction) is that patients can test positive even after they are no longer infectious, because the tests detect small amounts of viral RNA that most likely represent infected cells that have died. Newer “antigen-based” tests look for viral proteins instead of RNA. The antigen-based approach could potentially “be used to identify and isolate contagious individuals more effectively than current RNA-based (RT-PCR) testing,” coauthor Celine Roger-Dalbert of BD Life Sciences told Reuters. “Although it may not replace RNA-based testing, because we still need to identify anyone who was infected in order to trace the spread of the virus, it should help make isolation more efficient and effective as a public health intervention used to slow down the spread of COVID-19,” she added. The study results were published on Monday on medRxiv ahead of peer review. (bit.ly/2SBqkCg)
Intubation may be less risky for doctors than feared
Placing a tube in a patient’s airway, or removing it, is thought to be one of the highest-risk procedures for medical staff, because of the very close proximity to air being expelled through the mouth of a potentially infected person. But in operating rooms, at least, these procedures might present less of a risk of virus transmission than has been feared. In operating room experiments in anesthetized patients, intubation and extubation produced far fewer potentially virus-carrying aerosols than expected. Overall, 19 tube insertions generated about one thousandth of the aerosol generated by a single cough, the researchers reported on Tuesday in the journal Anesthesia. Fourteen tube removals produced more aerosols, but still less than 25% of that produced by a voluntary cough. The same might not be true in an emergency room setting. Surgical teams presently wear respirators and high level personal protective equipment to avoid aerosols. After each case, special cleaning is undertaken, which reduces operating room turnover and increases waiting times for operations, the authors say. The findings call for “reappraisal of what constitutes an aerosol-generating procedure and the associated precautions for routine anesthetic airway management,” they said. (bit.ly/3jG0usS)
Full beard need not rule out tight face mask seal
Frontline healthcare workers caring for COVID-19 patients must wear respirator face masks that form a tight seal with the skin, but full beards can make that impossible. Doctors in the UK have come up with a solution. The answer, outlined in a report published on Saturday in the Journal of Hospital Infection, involves covering the beard over the chin and cheeks with an under-mask elastic rubber sheet (as is used in yoga and pilates) and tying it in a knot at the top of the head. The technique was pioneered by a transplant surgeon and adopted by 32 bearded British healthcare providers, 30 of whom passed respirator fit tests, according to the report. “Bearded individuals who are unable to shave may have a new innovative technique to be able to wear respirator masks,” the authors write. While noting it was tested in a small number of people, the authors said, “it provides encouraging results to pave way for larger scale studies.” (bit.ly/2SCQyEB)
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