Defining a "Close Contact" for Contact Tracing of Covid-19 Transmission

A major tool currently used in controlling the spread of the virus outside China is contact tracing. This is trying to find people that have become infected by a known case of Covid-19.

This standard can also be used to help define "high risk" behavior if Covid-19 becomes an epidemic in your area.

1) Being within two meters (6 feet 6 inches) of an infected person for 15 minutes.
2) Being in the same office (defined as large open space) for two hours.
2b) Airplanes, because of their airflow of outside air, are defined as within 3 rows
3) Contact with secretions of infected person (this includes sneezes)

Anyone who is known to meet any of these criteria is then "traced" as potentially infected.

This may be useful information in case Covid-19 becomes widespread.

As of February 15th, no data (that I am aware of) has been released on how long the virus is viable on a surface. Given the behavior of other corona viruses (the four that cause 25% of common colds), this can be expected to be for an extended period measured in hours to a few days in ideal conditions (for the virus).

Studies have shown that the viral load in the noses (nasal passages) of asymptomatic people (those not aware that they are sick) infected with Covid-19 can be (at the high end) comparable to the viral loads of those that are clearly sick. Asymptomatic people will not cough as much, so they are not as contagious in that regard - but they are contagious.

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