It is not easy to tell the difference between being hospitalized ‘for Covid-19’ (primary Covid) and ‘with Covid-19’ (incidental Covid)


While patients having COVID incidentally is less worrying than them having severe COVID, it does not mean that there is nothing to worry about.

The complications of having COVID while also having other medical problems could still severely harm patients, Strain said.


A new way of breaking down hospitalization data in Massachusetts is giving physicians, and the public, a chance to understand better how COVID-19 is affecting patients.

But even though the new system now classifies almost half of hospitalizations with COVID as “incidental” as opposed to “primary,” that doesn’t mean the situation in the state’s hospital is any less serious than it’s been made out to be, say doctors.

On Thursday, the state launched a new method of reporting “primary” versus “incidental” cases. Primary cases are when someone is hospitalized because of COVID-19, whereas incidental cases are when patients test positive for COVID-19 after being hospitalized for other reasons. 

For example, someone with an incidental case could have come in for a broken bone or a heart attack, and only upon testing at the hospital learn they have COVID. 

Breaking down the data in this way, and knowing exactly how many patients are hospitalized primarily for COVID, makes it easier to compare current data to information from past waves, said Cassandra Pierre, an associate hospital epidemiologist and medical director of public health programs at Boston Medical Center.

“In previous waves, we’ve used this idea of hospitalization as a marker of severe COVID. And in a time where we have increasing levels of people who are vaccinated, it’s really important to understand what is the severity, what are we experiencing with each new wave?” Pierre said.

In past waves, for example the original spread of the virus in early 2020, basically all hospitalized people with COVID came to the hospital because of COVID or complications from the virus — so number of people hospitalized with COVID was a good indicator of the disease’s current severity. Now, that is not so much the case. 

State released COVID-19 data for Jan. 18 says of 3,192 hospitalized patients with COVID statewide, 52.2% are considered primary cases, and the remaining 47.8% tested positive while being hospitalized for other reasons. Basically this means, even with more people hospitalized with COVID than there were at this time last year, a smaller proportion of patients are severely ill because of the virus. 

Situation in hospitals is still dire

Even though recent numbers show about half of hospitalized patients with COVID weren’t admitted for it, which is a good indication for public health measures, the situation in hospitals is still dire. 

“The reality is that from the standpoint of the hospital and healthcare workers, it’s still pretty stressful. Even if half the people aren’t sick because of COVID, but they have it, it means they have to be really careful with how they deal with it and so there’s added cost and added stress,” said David Hamer, an attending physician in infectious diseases at Boston Medical Center.

Being diagnosed with COVID while hospitalized for something unrelated can also have a mental toll on the patient, both Hamer and Pierre said, due in part to the isolation protocols that are in place.


  • Some hospitals have started tracking patients who enter the hospital because of COVID-19 separately from people who show up for another medical reason and test positive on screening.
  • In New York, 57 percent of coronavirus-positive patients were admitted “for COVID,” while the rest were admitted “with COVID.”
  • All coronavirus-positive patients in the hospital pose a risk to healthcare workers and other patients, even if the patient showed up at the hospital for a non-COVID reason.


In Ontario, Canada, 54 percent of coronavirus-positive patients in the hospitals were admitted for COVID-19. However, “for COVID” patients make up 83 percent of ICU patients in the province.

This distinction is intended to better capture the pandemic’s burden on healthcare systems and society.

“Tracking these two types of patients helps us prioritize who can benefit from [certain] treatments in some cases,” said Dr. Tammy Lundstrom, an infectious disease specialist and chief medical officer at Trinity Health. “It will also help us to better understand the true severity of illness and death due to COVID infection.”

Experts caution that because of the need for strict infection-control measures, both groups of patients further strain hospitals at a time when COVID-19 hospitalizations in the United States are at a record high.

All coronavirus-positive patients in the hospital pose a risk to healthcare workers and other patients, even if the patient showed up at the hospital for a non-COVID reason.

“There are many patients for whom [coronavirus] infection can exacerbate their underlying condition — those with diabetes, cancer, underlying heart or lung disease, for example,” said Lundstrom.

To help prevent the transmission of the virus in the hospital, both “for COVID” and “with COVID” patients are isolated, said Lundstrom. Staff also need to wear personal protective equipment whenever they are around these patients.

Staff taking care of patients with COVID-19 are also not available to treat patients who do not have the coronavirus.

This can increase hospital staffing issues, said Lundstrom, but “we need to make sure we operate in a way that provides the best possible care without exposing other patients to infection.”

Healthcare systems are under considerable stress due to a surge in COVID-19 patients.

‘For COVID’ and ‘with COVID’ not always clear

While counting the number of patients in the hospital or ICU is straightforward, it is not always easy to determine whether a person is in the hospital “with” or “for” COVID.

Specific COVID-positive hospitalizations are clearly incidental — a person in a car accident or a child who breaks an arm falling off a swing.

However, because the coronavirus can affect multiple organsTrusted Source, including the heart, lungs, kidneys, skin, and brain, as well as cause blood clottingTrusted Source, COVID-19 can show up in many ways.

In a Jan. 4 Twitter thread, Dr. Ashish Jha, dean of the Brown University School of Public Health, gave the example of an 86-year-old man with kidney disease who had COVID-19 with fever and a sore throat.

“Two days of fevers caused him to become dehydrated [and] go into acute kidney failure,” Jha wrote. “His COVID is ‘better’ but he’s in the hospital with kidney failure. Was he admitted for COVID? No. With COVID? Yes.”

While some doctors might classify this patient as an incidental COVID-19 patient, others could argue that the man wouldn’t have had kidney failure if it weren’t for the coronavirus infection.

“Many patients present for a work-up of unusual symptoms, including those related to diarrhea/enteritis or blood clotting/vascular symptoms,” Dr. Howard Forman, a professor in the Yale School of Medicine, wrote on Twitter.

“These [cases] are being called ‘incidental,’ and we just do not know what contribution COVID is making, but it is likely significant,” Forman wrote.

“Some patients are admitted with typical stroke or myocardial infarction [heart attack], and these are almost always called ‘incidental,’ and they may well be,” he continued. “But we have strong evidence to support higher risk for these disorders in patients testing positive for COVID.”




This entry was posted in Uncategorized and tagged . Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s