COVID-19: Can normal breathing spread infection? | First antibody test gets FDA authorization

As of Thursday afternoon, the total number of confirmed COVID-19 cases has surpassed 1 million, with more than 50,000 deaths globally. In the United States, the number of confirmed cases has increased to more than 225,000, with over 5,000 deaths.

The death toll in the United States is not expected to peak until April 15th. The projected peak total of deaths has increased to 2,600 for that day, and the peak expected bed shortage has increased to 87,674, with an ICU bed shortage of 19,863.

With the projected US peak less than 2 weeks away, the race to study SARS-CoV-2 has ramped up. New research into transmission and true prevalence is aiming to shed more light on the extent of the pandemic.

Virus may be spread through normal breathing

A letter from the chair of a committee with the National Academy of Sciences said that results of current research are consistent with aerosolization of the virus through normal breathing, in addition to coughing or sneezing.

Harvey Fineberg, MD, wrote the letter in response to a query from the White House Office of Science and Technology Policy. 

The letter explained that research at a hospital in China revealed the virus could be suspended in the air as healthcare professionals remove protective gear, while floors are cleaned, or through movements of hospital staff. In addition, research from the University of Nebraska found that the virus could be detected in rooms more than 6 feet from a patient with COVID-19.

SARS-CoV-2 is not as infectious as measles or tuberculosis, but Dr. Fineberg suggested that aerosolized viral droplets may hang in the air, with the potential of infecting passersby. Variables for this scenario include how much viral shedding is present in a particular person and the amount of circulation in the room. A breeze will likely disperse the droplets outdoors.

Dr. Fineberg added that he is likely to begin wearing a non-surgical mask when he goes out in public.

FDA issues EUA for antibody test

The FDA has issued an emergency use authorization (EUA) for a serologic test that can identify past infections with SARS-CoV-2. These types of tests may be beneficial for clarifying the true prevalence of COVID-19, as the results will show which individuals have been infected while showing mild or no symptoms.

The test is manufactured by Cellex Inc. Currently, it can only be performed in a certified laboratory.

The FDA has previously discouraged antibody testing for the coronavirus, as antibodies can take time to develop. However, the agency has signaled that the benefits of the new test outweigh the potential risks. 

On Tuesday, a company falsely claimed the FDA had granted an EUA for its antibody test. Bodysphere claimed to have the FDA’s blessing for its 2-minute antibody test, but later stated that the test had not received authorization.

New York swabs the subway

Just how widespread is the novel coronavirus in the epicenter of the US outbreak? A team from Cornell Weill Medical School is investigating whether the virus is present in the New York subway system. The team has been testing for the virus in major cities around the world, such as Zurich, London, Tokyo, and Kolkata. The group anticipates obtaining more than 10,000 swab samples, representing 59 cities in 25 countries. 

The samples will run through 6 assays that can take anywhere from 20 minutes to 3 days. The unusually large number of assays is a result of the need to gain as much knowledge as possible about the once-in-a-century pandemic. 

As of yet, the team has not found SARS-CoV-2 in the New York subway system, but the number of samples collected so far is small. 

The team, which is led by Christopher Mason, PhD, associate professor, Cornell Weill Medical School, has found samples that include 10% human RNA and 1% to 2% viral DNA in the New York subway. The other 88% is RNA of unknown origin, which Dr. Mason said is not unusual for such a small number of samples.

At-home disinfection

Few studies have addressed which disinfectants are most efficacious against SARS-CoV-2, but scientists are operating under the assumption that this coronavirus will respond to agents that work against other viruses in the family.

The CDC recommends that frequently touched objects at home—such as tables, doorknobs, keyboards, and faucets—be disinfected daily. They also state that soiled surfaces should be cleaned with soap and water prior to disinfection.

One-quarter cup of bleach diluted in 1 gallon of cold water is effective against bacteria, fungi, and most viruses, including coronaviruses. Disinfecting abilities of this solution decrease over time, so it is recommended to use the solution within 24 hours.

Household items should have 10 minutes of bleach exposure before being wiped off, provided the items will not be damaged by the bleach. Non-porous items can be immersed in bleach for 30 seconds. 

Diluting alcohol with water to a solution of at least 70% is effective against coronaviruses. Objects should have a minimum of 30 seconds contact time. Pure alcohol will evaporate too quickly to properly disinfect a surface.

Vinegar, tea tree oil, and other natural products are not recommended for disinfection.