COVID-19 Q&A: As disease continues to spread, how accurate are hospitalization case counts?

June 28, 2022
Elke Shaw-Tulloch, Division of Public Health administrator

Idaho public health officials are watching several metrics as the number of COVID-19 cases increases across the state this month. One of those metrics is the number of people hospitalized who also have tested positive for COVID-19.

There is debate in some communities about why all patients who are hospitalized with COVID are counted, instead of only those who are hospitalized because of COVID. That debate centers around which of those numbers are the best way to assess COVID-19 risk in communities.

What does it mean to be hospitalized with COVID-19?

This measure counts infected people who are admitted to hospitals because they need medical care that may be for something other than COVID-19. They may only find out they have COVID-19 when they are tested for it as they are being admitted. Some people hospitalized with COVID-19 are sick from the virus, and are admitted for the virus-related illness. “Hospitalized with COVID-19” includes both groups, and is based on positive hospital admission test results among people living in a defined area. This measure is also called “COVID-19-associated hospitalizations,” and does not imply that all those hospitalizations were solely or even partially due to COVID-19 infection.

What does it mean to be hospitalized because of COVID-19?

This includes only people who are admitted to hospitals because they need medical care for a moderate or severe case of COVID-19. They often either suspect or know they have COVID-19 before going to the hospital, but this also may include people who initially went to the hospital with symptoms of a heart attack, stroke, or pneumonia, and were only discovered to have COVID-19 when they were tested at the hospital.

Is it important to count both?

Ideally, keeping track of both numbers is important because it shows how much COVID-19 is spreading in communities. Realistically, however, it is complicated, as some of the examples show. Some people who may appear to be hospitalized for unrelated reasons may actually have underlying COVID-19 illness making their symptoms worse.

Overall, it is most critical for hospitals and public health agencies to better understand how COVID-19 is affecting hospitals. Caring for someone who has COVID-19 in the hospital requires additional healthcare staffing, supplies, and space, whether they are there because of COVID-19 or for another reason. In either case, they must be isolated, and staff needs to take special precautions while caring for them.

The hospitals are reporting this data to the National Healthcare Safety Network (NHSN). The Centers for Disease Control and Prevention (CDC) gets it from that source and displays it on their data tracker and incorporates it into their COVID-19 Community Levels.

The CDC is aware this metric contains a mix of people who are sick with the disease and those who may be admitted for other reasons. It’s also worth noting that sometimes a person’s COVID-19 diagnosis is not completely clear. A person could go to the hospital because they have chronic lung disease and are having worsening cough or shortness of breath. If they are also infected with COVID-19, that could mean the virus is causing their chronic lung disease to be worse.

It's not a perfect measure, but hospitals cannot easily separate the positive test results, so this overall measure is what's used. If the number of admissions of people positive for COVID-19 is increasing, this indicates more COVID-19 virus circulating in our communities, and very likely reflects increases in those severely ill with the disease.

Is it legitimate to include ALL hospital patients with COVID-19 in community risk levels?

Including all hospital patients with COVID-19 when assessing community risk levels reflects the burden of disease in our communities, even if the disease isn’t severe for most. It will be severe for some.

For example: If 10 percent of admissions have COVID-19, but only half of those are being admitted for COVID-19 disease and the other half just happen to have COVID-19, the result STILL reflects a high community burden of disease because it’s making a lot of people sick and it also reflects a burden on the hospitals.

It shows that COVID-19 is circulating and causing infections in a large percentage of the population. The more it circulates, the more often it can mutate and potentially become more dangerous for people it infects.

Elke Shaw-Tulloch is the administrator of the Division of Public Health, and the state’s public health officer. She has worked for the department since 1996 and was promoted to division administrator in 2012. Since February 2020, she has focused most of her time on responding to the coronavirus pandemic. 

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