In December 2019, a novel corona virus infection was detected in Wuhan, China, Hubei province. Initial cases all had a common link to an large seafood and live animal marketplace. Corona viruses are a broad class of viruses that are responsible for most of the common colds, as well as several viral illnesses transmitted from animals to humans. They are so-named due to their similar appearance under electron microscopy to the sun's corona during a total solar eclipse (see Fig. 1, Fig. 2 1 , 2 ). The virus responsible for the current outbreak was originally called novel corona virus, now renamed SARS-CoV-2, since it is related to the SARS virus that caused an epidemic in China in 2002-2003 (postulated at that time to have originated in civet cats and then jumped to humans , and the MERS corona virus-related to transmission from camels https://www.cdc.gov/coronavirus/2019-nCoV/summary.html. The infection is now called COVID-19, and within a few weeks, it became clear that COVID-19 infection was easily spread from person to person, as there was an exponential rise in newly-reported cases seen in China. Travelers from China then spread the COVID-19 to other countries, causing the WHO to declare the epidemic a Global Health Emergency on January 30, 20203 . Simple recommendations of respiratory protection and glove use early on in the official guidance from health agencies contrasted sharply with wide coverage in the 24-hour news media, showing graphic pictures of civilian authorities and health care personnel in Asian countries wearing extensive protective gear reminiscent of that used for Ebola or even hazmat incidents. While initially it was felt that droplet transmission was most the likely mode, recommendations have been upgraded to airborne and contact transmission, since the natural course of this infection is still not completely understood, infectivity or contagiousness seems higher than SARS, and people seem to be able to transmit infection before they ever become symptomatic, and for some days after seemingly full recovery (https://www.cdc.gov/coronavirus/2019-ncov/about/transmission.html) (Figs. 3 4 , 3a 5 , 6 , 4a 7 ).
Fig. 1 Coronavirus- CDC.
Fig. 2 NASA: Sun's Corona during Solar Eclipse August 21, 2017.
Fig. 3 CDC- airborne particles from a sneeze.
Fig. 3a NIOSH- Approved N95 mask (above) and N95 duck bill and other styles (below).
Fig. 4a fit testing N95 mask with qualitative solutions (isoamyl acetate, saccharine, etc.).