Over the last 34 years lessons learned from the dental office, are very helpful in stopping the spread of Covid-19. In the 1980’s the disease AIDS required a new set of “Universal Precautions” in the dental setting. Unlike AIDS, Covid-19 appears to be transmitted through the air. Because Covid-19 is airborne, to control the virus’s spread, “Universal Precautions” will be required in all settings. “Universal Precautions” are required where anyone could be an asymptomatic carrier, thus everyone is treated as an infected person.
All dental personal see a video “if saliva were red” showing a half hour dental procedure with a bright red saliva stain. Several versions of this video have been produced. A patient has his/hers saliva stained red. Even in the old black and white version of the film, virtually every area of the dental office ends up with a red stain. Protective eyewear that dentist and dental assistant wear have red spots, as do dental records, phones, all surfaces though out the office. The color version is a real eye opener.
The key to stopping Covid-19 is to get the infection rate (R) from person to person transmission under 1. The (R) rate tells you the average number of people who will contract a contagious disease from one person with the disease. Lets take a look at five infectious cycles for a contagious disease where the infection starts with a single person. Covid-19 has a (R) rate of over 3. Over a 5 course cycle of infections with an (R) rate of 3 we find the following: without mask and social distancing one person infects 3, who infect 9, who infect 27, who infect 81. With some social distancing and a few people wearing mask, one person infects 2, who infect 4, who infect 8, who infect 16. With everyone wearing a mask, the infection rate drops below one. Using an infection rate of .8 means that one person has an 80% chance of infecting another, but a 20% chance of not infecting someone. The next infected person has a 20% chance of not infecting someone. Eventually in this chain of events there will be a failure of the next infected person to infect someone and the virus dies out.
Without mask and social distancing, after 5 cycles 81 people are getting infected. With masks, hand washing, and social distancing the infection rate drops to less than one and few will be infected after 5 infectious cycles. With each additional cycle beyond 5 cycles and wearing mask and careful sanitation the virus eventually dies out. The better we social distance and wear masks, the faster the virus dies.
If your Grandparents were stuck in a car on a railroad track and you could throw a switch to save them from the oncoming train, would you throw the switch? Since it is the elderly that are at more risk, and since you could be an asymptomatic carrier, you could be the proverbial “covid-19 train” bearing down on your Grandparents. Over 50% of Covid-19 carriers are asymptomatic. Wearing a mask could save your Grandparents or some other retired citizen. Please stop the “Covid-19 Train” that is killing our Grandparents. Remember some younger folks have been disabled by this outbreak. Wear your mask!!