The current estimation of median incubation period of the virus is ~4 days. This is 1 day shorter than two previous estimates. (https://wwwnc.cdc.gov/eid/article/26/7/20-0282_article). The incubation period determines the average length of time between infection and displaying symptoms, but that does not mean that patients cannot spread the virus before they demonstrate symptoms. The coronavirus can start being shed within two days of contraction; for context, the flu is generally shed in the first few days upon demonstrating symptoms. This is what makes the coronavirus so easily transmissible: many people are beginning to shed the viral load before they have any inkling that they may be sick. (“Clinical presentation and virological assessment of hospitalized cases of coronavirus disease 2019 in a travel-associated transmission cluster”). The good news is that the virus does generally stop shedding when the patient goes into recovery, which is usually 8 or more days after contraction. (https://www.statnews.com/2020/03/09/people-shed-high-levels-of-coronavirus-study-finds-but-most-are-likely-not-infectious-after-recovery-begins/).

Dr. Jeffrey N. Martin, a professor in the Department of Epidemiology and Biostatistics at the University of California, San Francisco, said that "At this point, I don't think anyone can take a group of people with COVID, say how each person has become infected, and then say that xx% got infected with droplets and yy% got infected via touching surfaces." This kind of study has not been conducted for any viral infection previously. A study published April 16 in the New England Journal of Medicine found that virus particles that were aerosolized could remain viable for up to 3 hours. This could lead to many new infections from one source, especially in a public outdoor setting. One study found that SARS-CoV-2 could remain viable on surfaces such as cardboard for up to 24 hours, and on plastic and steel for 2 to 3 days. However, ultimately the most common route of transmission is hypothesized to be through droplets from sneezing or coughing.

The results of these tests have been wildly inconclusive. According to the Center for Evidence-Based Medicine, “between 5-80%” of people testing positive for COVID-19 may be asymptomatic. Younger people are more likely to be asymptomatic. Most asymptomatic cases are not hospitalized and are recommended to self-isolate for two weeks in their homes. (Source)

Remdesivir is a nucleotide analogue prodrug originally tested in Ebola patients. It is being used for patients with severe COVID-19 through a compassionate release. In the study conducted by New England Journal of Medicine, 68% of patients saw improvement after being treated with Remdesivir (https://www.nejm.org/doi/full/10.1056/NEJMoa2007016). Gilead Sciences is the company that works to produce Remdesivir. Currently, the company has committed to providing the drugs for studies in 70 countries through the WHO. “In anticipation of potential future needs, we have accelerated manufacturing timelines to increase our available supply as rapidly as possible.” (https://www.gilead.com/-/media/gilead-corporate/files/pdfs/covid-19/gilead_rdv-development-fact-sheet-2020.pdf). The production goals are

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