Little is known about the effectiveness of personal protective equipment for health care workers who take care of patients infected with the novel coronavirus.
The Annals of Internal Medicine today published a report that describes the clinical outcome of health care workers who took care of a patient with severe pneumonia before the diagnosis of COVID-19 was known.
The patient was a middle-aged man who was hospitalized in February 2020 for community-acquired pneumonia. He had not traveled recently to China nor had had contact with anyone known to have COVID-19. He required supplemental oxygen on admission; the following day, he developed respiratory distress that required endotracheal intubation by the emergency airway team and mechanical ventilation in the intensive care unit (ICU).
He was transferred to the ICU for intubation and had a difficult intubation that required use of a video laryngoscope and an airway bougie. He improved clinically after three days of mechanical ventilation and was subsequently extubated to noninvasive ventilation. On the day that the patient was extubated, he tested positive for COVID-19.
During the patient’s admission, 41 health care workers were identified as having exposure to aerosol-generating procedures for at least 10 minutes at a distance of less than two meters from the patient. All 41 health care workers were placed under home isolation for two weeks, with daily monitoring for cough, dyspnea, and myalgia and twice-daily temperature measurements. None of the exposed health care workers developed symptoms, and all subsequent tests were negative.
The primary route for the spread of COVID-19 is thought to be through aerosolized droplets that are expelled during coughing, sneezing, or breathing, but there also are concerns about possible airborne transmission. In the situation we describe, 85% of health care workers were exposed during an aerosol-generating procedure exposed while wearing a surgical mask, and the remainder were wearing N95 masks. That none of the health care workers in this situation acquired infection suggests that surgical masks, hand hygiene, and other standard procedures protected them from being infected.
Our observation is consistent with previous studies that have been unable to show that N95 masks were superior to surgical masks for preventing influenza infection in health care workers. We emphasize, however, that nearly all experts recommend that health care workers wear an N95 mask or equivalent equipment while performing an aerosol-generating procedure. We recognize the limitations of this single case report and acknowledge that additional studies are necessary to determine how best to protect health care workers from becoming infected while they are providing care for patients with COVID-19.
Source: Annals of Internal Medicine