State changes COVID reporting to distinguish between primary and incidental hospital cases

The coronavirus is so widespread in Massachusetts that the state health department is now asking hospitals to divide patients who test positive into two groups: primary and incidental cases.

Primary refers to patients hospitalized because they have a serious case of COVID-19. The incidental patients are those who happen to test positive when they arrive with some other urgent problem. Data from the first week using this kind of reporting show a near-even split between the two.

The distinction is supposed to offer a clearer view of just how much severe illness COVID is causing patients and help hospitals manage the burden of this disease. Patients with incidental COVID still have to be isolated, and staff must still take extra precautions when caring for them, but they may be less likely to need intensive oxygen support, for example.

Some doctors say the picture created by this new reporting requirement is murky because it will miss many patients with serious cases of COVID. Hospitals are told to identify primary COVID patients based on whether they were prescribed the steroid dexamethasone, often used to reduce lung inflammation linked to COVID. Physicians say that filter won’t capture patients who have heart problems or blood clots related to COVID, those who are readmitted with lingering COVID ailments, or someone who falls while they are home sick with COVID.

“The key thing here is to recognize that this change in definition is likely erring on the side of undercounting patients who are admitted to hospitals with acute COVID,” says Dr. Jason Wasfy, a cardiologist and medical director with the Massachusetts General Physicians Organization.

The Massachusetts Department of Public Health says the use of dexamethasone is considered an indicator of moderate to severe COVID and will capture the vast majority of patients.

“While there is no single proxy that has been identified that will correctly identify all cases without inaccurately including others … over 90% of cases hospitalized due to COVID received the steroid as part of their treatment,” a DPH spokeswoman said in an email.

The statewide numbers may mask some important regional variations. Some hospitals in Boston have been seeing a growing number of incidental COVID cases for weeks, while hospitals in Brockton and Lawrence reported very few earlier this month.

And there are questions about how a change in reporting who has serious COVID and who doesn’t in Massachusetts will affect national comparisons. The state health department says there is no national standard for reporting COVID hospitalizations, but that several states are watching how this distinction works as they see more patients with what’s considered an incidental positive test result.