CDC recommends people wear cloth masks to block the spread of COVID-19

Fact. Yes. Surgical masks and N95 respirators should be set aside for healthcare workers.

The Centers for Disease Control and Prevention (CDC) has released guidelines to recommend that US people should wear homemade face coverings to prevent the spread of the novel coronavirus.

The CDC has also advised simple cloth coverings to prevent people who may have the virus and are unaware, from transmitting it to others.

The White House task force and the CDC were re-evaluating the mask recommendations over the past few days. Research has suggested that people who do not have symptoms can infect others, and the virus may spread when people speak or breathe. It is not merely by coughing or sneezing. Considering the new evidence, the CDC and the task force recommend that people wear cloth face coverings in public settings where it might be difficult to maintain other distancing measures.

If people cover their faces with a cloth mask or another such barrier, it may decrease the amount of virus-laden particles they release.

While there is limited evidence to suggest that these substitute masks prevent the spread of disease, some research suggests that they limit the amount of particles a person wearing them spreads. Some experts say that it is better to use these makeshift masks than nothing. The CDC further states that people should remain six feet apart when in public as much as possible, even if they’re wearing masks.

Some cities and states, like Colorado and New York City, had already advised people to cover their faces when out in public. (Source: The Verge)

There are Groups at Higher Risk for Severe Illness

Fact: According to what is known, those at high-risk for severe illness from COVID-19 include:

People >65 years of age

People residing in a nursing home or long-term care facility

People of all ages with underlying medical conditions have increased risk of severe illness, more so, if the underlying medical conditions are not well controlled. This includes individuals with:

 Chronic lung disease or moderate to severe asthma

Serious heart conditions

Conditions that can predispose a person to be immunocompromised, including cancer treatment, smoking, bone marrow or organ transplantation, immune deficiencies, poorly controlled HIV or AIDS, and prolonged use of corticosteroids and other immune weakening medications.

Severe obesity (body mass index [BMI] >40)

Diabetes

Chronic kidney disease and those who are undergoing dialysis

Liver disease. (Source: CDC)

Younger people can be serious

Yes, Fact: In Italy, with one of the largest outbreaks of COVID-19 in the world, 10-15% of all people in intensive care are under 50.

In Korea, one in six deaths have been reported in people below the age of 60.

Last month, world health officials highlighted a study in China that assessed 2,143 cases of children with confirmed or suspected COVID-19 that were reported to the Chinese Centers for Disease Control and Prevention from Jan. 16 to Feb. 8. Over 90% of the cases were asymptomatic, mild or moderate cases. Around 6% of the children’s cases were severe or critical, compared with 18.5% for adults. (Source: CNBC)

Stability of SARS-CoV-2 in different environmental conditions

Fact: According to a study published in The Lancet Microbe, SARS-CoV-2 can be highly stable in a favorable environment, but it is also susceptible to standard disinfection methods.

Alex W. H. Chin, MD, University of Hong Kong, Hong Kong, China, and colleagues conducted various experiments to test the stability of SARS-CoV-2 at different temperatures, on various surfaces, and its susceptibility to disinfection methods. 

The researchers assessed the stability of SARS-CoV-2 at different temperatures. SARS-CoV-2 in virus transport medium (final concentration ∼6.8 log unit of 50% tissue culture infectious dose [TCID50] per mL) was incubated for up to 14 days and was then tested for its infectivity. 

Results showed that SARS-CoV-2 is highly stable at 4 degrees Celsius, but has sensitivity to heat. At 4 degrees Celsius, only around 0.7 log-unit reduction of infectious titre was noted on day 14. As the incubation temperature increased to 70 degrees Celsius, the time for virus inactivation decreased to 5 mins.

Researchers then assessed the stability of the virus on varying surfaces, including paper, tissue paper, wood, cloth, glass, banknotes, stainless steel, plastic, and surgical masks. A 5 μL droplet of virus culture (∼7.8 log unit of TCID50 per mL) was pipetted on a surface and left at room temperature (22 degrees Celsius) with a relative humidity of around 65%. The inoculated objects retrieved at desired time-points were soaked with 200 μL of virus transport medium for a span of 30 mins to elute the virus. 

No infectious virus was recovered from printing and tissue papers after a 3-hour incubation, while no infectious virus could be detected from treated wood and cloth on day 2. On the contrary, the virus was more stable on smooth surfaces. No infectious virus could be detected from treated smooth surfaces on day 4 (glass and banknote) or day 7 (stainless steel and plastic). 

Of note, a detectable level of infectious virus was still present on the outer layer of a surgical mask on day 7 (∼0.1% of the original inoculum). 

Can povidone iodine kill the virus

Yes; in the study published in The Lancet Microbe, researchers assessed the virucidal effects of disinfectants by adding 15 μL of the virus culture (∼7.8 log unit of TCID50 per mL) to 135 μL of various disinfectants at working concentration.

Disinfectants included household bleach, hand soap, ethanol, povidone-iodine, chlorhexidine, and benzalkonium chloride. With the exception of a 5-minute incubation with hand soap, no infectious virus was detectable after a 5-minute incubation at room temperature. 

Can the virus survive in waste water

In an article, published in The Lancet Gastroenterology & Hepatology, researchers have reported the detection of SARS-CoV-2 in wastewater. 

From February 17, 2020, onwards, Willemijn Lodder, and Ana Maria de Roda Husman, Centre for Infectious Disease Control, Bilthoven, the Netherlands, took samples once a week from human wastewater collected at Amsterdam Airport Schiphol, Haarlemmermeer, the Netherlands. Samples tested positive for virus RNA as per quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) methodology 4 days after the first cases of COVID-19 were identified in the Netherlands on February 27, 2020.

This could be attributed to virus excretion from potentially symptomatic, asymptomatic, or pre-symptomatic individuals passing through the airport.

Human wastewater sampled near the first Dutch cases in Tilburg, Netherlands, had also tested positive for the presence of viral RNA within a week of the first day of disease onset.

This suggests that wastewater could serve as a sensitive surveillance system and early warning tool, as was previously shown for poliovirus.

Feco-oral transmission

Fact: It is not yet clear if the SARS-CoV-2 is viable under environmental conditions that could promote fecal-oral transmission. However, the possibility of fecal-oral transmission of COVID-19 has implications, particularly in areas with poor sanitation where diagnostic capacity might be limited, such as Africa. Wastewater surveillance, especially in areas with a scarcity of data, might provide information, as we have previously shown in monitoring antibiotic resistance on a global scale.

Can you convert anesthesia machines into ventilators

American Society of Anesthesiologists (ASA) has published guidance on how to safely and effectively convert anesthesia into life-sustaining mechanical ventilation for patients during the COVID-19 pandemic, when there is scarcity of ICU ventilators. 

Although guidance is available from the manufacturers, the guidance may not convey all of the clinical considerations. Anesthesia professionals will be needed to put these machines into service and to manage them while in use. Safe and effective use requires an understanding of the capabilities of the machines available, the differences between anesthesia machines and ICU ventilators, and how to set anesthesia machine controls to mimic ICU-type ventilation strategies.

[References: https://www.thelancet.com/journals/lanmic/article/PIIS2666-5247(20)30003-3/fulltext, The Lancet Microbe; https://www.thelancet.com/journals/langas/article/PIIS2468-1253(20)30087-X/fulltext, The Lancet Gastroenterology & Hepatology; American Society of Anesthesiologists]

Dr KK Aggarwal

President CMAAO