CMAAO CORONA FACTS and MYTH BUSTER 80
Dr K K Aggarwal
President Confederation of Medical Associations of Asia and Oceania, HCFI, Past National President IMA, Chief editor Medtalks
With additional inputs from Dr Monica Vasudeva
778: Universal Face Shields for COVID-19
The CDC currently recommends all Americans wear cloth masks in public to curtail transmission of COVID-19 coronavirus, but another form of personal protective equipment might be a better idea: plastic face shields.
A JAMA Viewpoint recently published by Eli Perencevich, MD, of the University of Iowa, and colleagues discussed how face shields for the community may be a viable alternative.
Face shields can be reused indefinitely and are easily cleaned with soap and water, or common household disinfectants. They are comfortable to wear, protect the portals of viral entry, and reduce the potential for autoinoculation by preventing the wearer from touching their face.
And unlike medical masks, face shields do not have to be removed to communicate with others.
A simulation study of influenza virus found face shields reduced viral exposure by 96% when worn within 18 inches of a cough, and when this study was repeated using the recommended distancing protocol of 6 feet, inhaled virus was reduced by 92%. Face shields are also an important PPE component for healthcare workers.
779: COVID-19 Might Be Most Transmissible in the Presymptomatic Period
Anthony L. Komaroff, MD reviewing He X et al. Nat Med 2020 Apr 15
Peak infectivity is estimated to occur 2 days before symptom onset.
Influenza is most transmissible at or just before the onset of symptoms, whereas SARS is most transmissible at 7 to 10 days after symptom onset.
A team from Wuhan, China, created models based on data from two different studies of patients with COVID-19. First, they obtained 414 serial throat swabs from 94 moderately ill patients, starting at symptom onset and continuing for the next 32 days. Second, they obtained data from 77 transmission pairs and estimated an incubation period of 5.2 days. The researchers found the highest viral loads on throat swabs collected at symptom onset; the loads rapidly declined during the next 7 days. They estimate that 44% of secondary cases were infected in the 2 days prior to onset of symptoms, at least among transmissions that occurred among people in close contact (e.g., households).
The researchers' conclusion, that COVID-19 is highly infectious in the 2 days before symptom onset, is based on modeling: No samples were obtained in patients prior to onset of symptoms. Nevertheless, these findings are consistent with anecdotal evidence of relatively frequent spread by asymptomatic carriers. If this hypothesis is correct, quarantining will be less effective in controlling this virus than it was with SARS, and aggressive tracing of contacts will be critical. NEJM
780: SARS-CoV-2 Found in Aerosols in Hospital Staff Areas, Public Places;
Edited by David G. Fairchild, MD, MPH, and Jaye Elizabeth Hefner, MD
New findings, published in Nature, add to the evidence indicating that SARS-CoV-2 can persist in aerosol samples. Researchers in Wuhan measured SARS-CoV-2 RNA concentrations in aerosol samples taken from 30 sites inside two hospitals dedicated to treating COVID-19, as well as from several public areas.
Patient areas: Viral RNA concentrations generally were very low or undetectable in patient areas (e.g., ICUs, coronary care unit), except in a patient mobile toilet room, which was not ventilated.
Medical staff areas: Some sites — including rooms where personal protective equipment was removed — had high SARS-CoV-2 RNA levels; these levels became undetectable after better sanitization procedures were implemented.
Public areas: Two areas that got a lot of foot traffic — the entrance to a department store and a site next to one of the hospitals — had high viral RNA concentrations.
SARS-CoV-2 may have the potential to be transmitted via aerosols. Room ventilation, open space, sanitization of protective apparel, and proper use and disinfection of toilet areas can effectively limit the concentration of SARS-CoV-2 RNA in aerosols. [NELM]
781: COVID-19 in Healthcare Personnel
Stephen G. Baum, MD reviewing Heinzerling A et al. MMWR Morb Mortal Wkly Rep 2020 Apr 17 Burrer SL et al. MMWR Morb Mortal Wkly Rep 2020 Apr 17 Chow EJ et al. JAMA 2020 Apr 17
Initial data on vulnerability to, manifestations of, and steps to prevent COVID-19 in healthcare workers are presented in three early studies.
SARS-CoV-2 infection of healthcare personnel (HCP) was inevitable, given that the virus is highly contagious via the respiratory route and appears to be transmitted from symptomatic, presymptomatic, and asymptomatic persons and given the ongoing shortage of appropriate personal protective equipment (PPE).
Three groups now report details of early HCP infections with SARS-CoV-2.
Heinzerling and colleagues report HCP exposure from one of the earliest community-acquired cases in Solano County, California, in February 2020. An unsuspected, and therefore undiagnosed patient underwent multiple aerosol-generating procedures while under only standard precautions and exposed an apparent 121 HCP, of whom 35.5% developed COVID-19–compatible symptoms within 14 days of exposure and were tested for SARS-CoV-2.
Of these, 3 had positive tests; these and 34 other HCP were interviewed. The process identified that risk factors for COVID-19 acquisition included doing a physical examination and having long exposure during nebulizer treatments.
Those with high or medium risk were furloughed and monitored. Over the course of monitoring a total of 145 HCP with potential exposure, 36% became symptomatic and were tested for SARS-CoV-2, still yielding only the 3 positive HCP, one deemed at medium exposure risk and 2 at high risk. None of these 3 HCP consistently wore significant PPE. Because little community infection was present, and given the lack of HCP PPE, these infections are considered to be work-associated.
Burrer and colleagues characterize 9282 HCP-associated cases of COVID-19 reported in the U.S. up to April 9, 2020. Median age was 42 years and 73% were female, mirroring the HCP population at large. Where racial data were available, 72% were white, 21% were Black, and 5% were Asian. Exposure occurred in healthcare (55%), households, and community settings, and 38% reported at least one underlying health condition. Although most reported fever, cough, or shortness of breath, 8% reported no symptoms. Most (90%) were not hospitalized, but severe outcomes including 27 deaths occurred, mostly in HCP ≥65 years.
Chow and colleagues examine the efficacy of current COVID-19 screening practices in HCP. Of 50 HCP identified as exposed and infected in King County, Washington, in February 2020, where the first outbreak in a long-term care facility was reported, 48 were interviewed. Median age was 43 years, 77.1% were female, and 77.1% were involved in direct patient care; 47.9% had chronic medical conditions. The most common symptoms were cough (50%), fever (41.7%), and myalgias (35.4%). Of the 16.7% without cough, fever, shortness of breath, or sore throat, the most common complaints were chills, myalgias, coryza, and malaise.
The authors calculate that if chills and myalgias had been included in screening, case detection would have increased from 83.3% to 89.6%. Of those interviewed, 64.6% reported working a median of 2 days (range, 1–10 days) while symptomatic. [NEJM Reproduced]
782: A pregnant woman in Switzerland delivered a stillborn infant at 19 weeks' gestation after testing positive for COVID-19
David Baud, MD, PhD, of the Lausanne University Hospital in Switzerland, and colleagues "This case of miscarriage during the second trimester of pregnancy in a woman with COVID-19 appears related to placental infection with SARS-CoV-2, supported by virological findings in the placenta," Baud's group wrote in a research letter in JAMA.
After delivery, swabs and biopsies of the placenta tested negative for bacterial infection, but positive for SARS-CoV-2. The placenta remained positive at 24 hours after delivery.
Placental infection resulting in miscarriage or fetal growth abnormalities were observed in 40% of maternal infections with SARS and MERS coronaviruses.
783: The novel coronavirus (SARS-CoV-2) stays significantly longer in stool than in the lungs and serum
The management of stool samples is important for controlling the virus, clinicians in China report.
Reuters: Dr. Tingbo Liang and colleagues of First Affiliated Hospital in Hangzhou estimated the viral load from 3497 respiratory, stool, serum and urine samples from 96 patients with SARS-CoV-2 infection.
Infection was confirmed in all patients via sputum and saliva samples, they report in a fast-track report in The BMJ.
RNA was detected in the stool of 55 (59%) patients, in the serum of 39 (41%) patients, and the urine of only one patient.
The average lifespan of the virus was 22 days (range 17-31 days) in stool compared to 18 days (range 13-29 days) in respiratory tissue and 16 days (range 11-21 days) in serum, the researchers report.
The virus persists for a longer period and peaks later in respiratory tissue in people with severe disease. The average duration of virus in respiratory samples of patients with severe disease was 21 days (range 14-30 days) compared with 14 days (range 10-21 days) in those with mild disease.
In those with mild disease, the viral loads peaked in respiratory samples in the second week after disease onset, whereas viral load continued to be high during the third week in those with severe disease.
Reducing viral loads through clinical means and strengthening management during each stage of severe disease should help to prevent the spread of the virus.
The virus lasts longer in men than women and in patients over age 60 years, which may partly explain the high rate of severe illness in older patients.
784: Case Definition Published for Rare Child Syndrome
UK paediatricians have published a working definition of an inflammatory syndrome affecting a very small number of children that may be linked to COVID-19.
The working definition includes:
A child presenting with persistent fever, inflammation and evidence of single or multi-organ dysfunction with additional features. This may include children fulfilling full or partial criteria for Kawasaki disease.
Exclusion of any other microbial cause.
SARS-CoV-2 PCR testing may be positive or negative.
785: Nearly two-thirds of U.S. patients with COVID-19 report gastrointestinal symptoms, according to a multicenter study.
Harvard Medical School: Overall, 61.3% of patients presented with at least one gastrointestinal symptom, including most commonly anorexia (34.8%), diarrhea (33.7%), and nausea (26.4%).
Gastrointestinal symptoms were the initial symptoms in 14.2% of patients and were the predominant presenting complaint in 20.3% of patients, according to the online report in Gastroenterology.
More patients with than without gastrointestinal symptoms also reported fatigue (65.1% versus 45.5%, respectively), myalgia (49.2% versus 22%), sore throat (21.5% versus 9.8%), and loss of smell or taste (16.9% versus 6.5%).
Nausea and anorexia were significantly associated with anosmia and ageusia after controlling for other factors, whereas other gastrointestinal symptoms were not.
Laboratory findings did not differ significantly between patients with and without gastrointestinal symptoms.
Among 202 patients who had completed their hospitalizations at the time of data analysis, 17.5% required a stay in the ICU, 13% required mechanical ventilation, and 15.8% died. These rates did not differ significantly between patients with and without gastrointestinal symptoms.
COVID-19 should be considered in patients presenting with new or acute-onset digestive symptoms, even in the absence of respiratory complaints, fevers, or other typical COVID-19 symptoms.
Failure to identify COVID-19 patients with primarily digestive symptoms may lead to delayed care, inadequate isolation, and further transmission.
Patients presenting with new or acute-onset digestive symptoms should be triaged and treated in the same way as patients presenting with respiratory COVID-19 symptoms.
786: Fact: There were trends toward lower rates of ICU stay and death in the group with gastrointestinal symptoms, which is similar to early trends we have seen in New York City.