Responses to COVID-19
Measures taken against COVID-19 can be tied to the different basic reproductive numbers, or R0. Masks comprised of different materials make a huge influence in contact rates for the COVID-19 virus. Throughout the pandemic, several types of masks were mass-produced to protect people from the airborne virus: blue-surgical, N95s, and homemade cloth masks. Recent research shows the difference in effectiveness of each of these masks with protection against contracting COVID-19. In a study conducted by the Center for Disease Control, researchers found that cloth masks lowered the odds of contracting the virus by 56% (Andrejko et. al.; 2022). Next, they found that surgical masks lowered the risk by 66% (Andrejko et. al.; 2022). Finally, they found that N95/KN95 masks lowered odds by 83% (Andrejko et. al.; 2022).
These masks can be correlated connected to the concept of basic reproductive number from class. R0 is calculated by multiplying possible number of hosts (k) times infection rate (p) (Easley and Kleinberg; 2016). If R0>1, the disease will continue to reproduce (Easley and Kleinberg; 2016). If R0<1, the disease will cease to reproduce (Easley and Kleinberg; 2016). Although we can’t determine the exact infection rate of COVID-19, we can make assumptions on the value of each mask’s R0 value. The sequence would look something like the following: R0(No Mask)>R0(Cloth Mask)>R0(Surgical Mask)>R0(N95 Mask)>1. Since using no mask is obviously not effective in controlling the disease, it has the highest value for R0. This is followed by each slightly more effective mask method: cloth masks, surgical masks, and N95 masks. We can assume that each of these R0 values are greater than 1 as each one of these methods are not enough to put an end to the virus.
Researchers noticed that wearing a mask was not going to be enough to end the COVID-19 Pandemic. As a result, policies were put in place to mandate a nation-wide quarantine. All citizens, besides essential workers, were to stay indoors for several weeks. People no longer attended jobs or school in-person. These researchers thought that the best method to combat the virus was to reduce the k value (number of hosts) of the basic reproductive number equation. Although R0 would did not have fall below 1 (the disease continued to spread). The mass quarantine heavily reduced the contraction rate in an effort to produce a vaccine.
Sources
Andrejko KL, Pry JM, Myers JF, et al. Effectiveness of Face Mask or Respirator Use in Indoor Public Settings for Prevention of SARS-CoV-2 Infection — California, February–December 2021. MMWR Morb Mortal Wkly Rep 2022;71:212–216. DOI: http://dx.doi.org/10.15585/mmwr.mm7106e1
Easley, David, and Jon Kleinberg. “Epidemics and the Branching Process Model.” Networks, Crowds, and Markets, 26 April 2016, Cornell University, https://learning.edx.org/course/course-v1:CornellX+INFO2040x+1T2016/block-v1:CornellX+INFO2040x+1T2016+type@sequential+block@93476177d47d4d1c914c044a6f6c31d3/block-v1:CornellX+INFO2040x+1T2016+type@vertical+block@2b5cdf104de247de84c49a04ddfdfb7e. Lecture.