Can we know the numbers of active COVID-19 cases and the number recovered? Sort of

Every day, the Mississippi State Department of Health reports the number of confirmed new cases and deaths from the virus from the previous day, adding them to the state’s cumulative total of COVID-19 cases and deaths.

Many also want to know how many people have recovered from the virus, and how many active cases are still in their county.

MSDH has been providing a statewide estimate of those presumed recovered using the following information:

• A person can be presumed recovered if:
  • It has been 14 days or more since they tested positive and they were not hospitalized.
  • It has been 21 days or more since they tested positive and they were hospitalized, or hospitalization is unknown.

As of May 17, MSDH estimates that 7,681 people can be presumed recovered, or about 58% of the state’s 13,252 confirmed cases as of Sunday. (MSDH says its presumed recovered estimate will be updated weekly. It was not updated Sunday)

Based on the information provided from MSDH on its website, Mississippi does not seem to be tracking every confirmed case of illness unless that person is hospitalized (and may not be tracking every person who has been hospitalized after their release). Without that exact data, it is not possible to provide anything more than an estimate of recovered and active cases.

Also, because MSDH has not released the numbers of people hospitalized by county, any calculation of a county’s recovered and active cases must use the 21-day benchmark.

The calculation looks like this: Go back 21 days to the number of infections, subtract the known outcomes (deaths) to get the number of people presumed recovered. Active cases would be presumed recovered plus deaths subtracted from cumulative infections to date.

In Warren County, the number of cases reported 21 days ago (Sunday, May 3) was 81. Number of deaths to date (known outcomes) is six. 81 – 6 = 75 presumed recovered.

Number of cumulative cases to date (Sunday, May 24) is 150. 150 – 75 (presumed recovered) – 6 deaths = 67 active cases.

Note that these are only estimates. Without additional data, it is not possible to know exact numbers.

In addition, because cases are reported in the county where that person resides, not the county where he or she was tested or is hospitalized, it would be inaccurate to say that active cases are currently in the county. They could, for example, be hospitalized in Jackson. Conversely, a person hospitalized in Warren County may not be counted in Warren County’s COVID-19 cases or deaths because their permanent address is in Claiborne or Yazoo County.