In case you needed one more thing to worry about. Until I read this article at the NY Times I was under the impression the impact of the coronavirus was limited to clogging up people’s lungs, often seriously enough that they needed the help of machines to breath. But it turns out doctors around the world have also seen a subset of coronavirus patients who experience serious mental problems. The exact mechanism for this is still unknown but it’s pretty frightening that the first symptom of the virus some people experience isn’t a cough but confusion:

In early March, a 74-year-old man came to the emergency room in Boca Raton, Fla., with a cough and a fever, but an X-ray ruled out pneumonia and he was sent home. The next day, when his fever spiked, family members brought him back. He was short of breath, and could not tell doctors his name or explain what was wrong — he had lost the ability to speak…

On Tuesday, doctors in Detroit reported another disturbing case involving a female airline worker in her late 50s with Covid-19. She was confused, and complained of a headache; she could tell the physicians her name but little else, and became less responsive over time. Brain scans showed abnormal swelling and inflammation in several regions, with smaller areas where some cells had died.

The Detroit Free Press published a story about the woman’s case yesterday. It notes that she had coughs and aches for several days before she was taken to the hospital and diagnosed. But the Times cites two studies suggesting more seriously ill patients are more likely to display these symptoms:

[A] Chinese study in February said that about 15 percent of those patients with severe illness experienced a change in mental status, compared with 2.4 percent of those who did not have severe illness, according to that study.

Another study, published in the British Medical Journal in late March, found that of 113 patients from Wuhan who died of Covid-19, 22 percent had experienced disorders of consciousness, ranging from somnolence to deep coma, compared with only 1 percent of another group of patients who recovered from the illness.

However, another example given in the story involves four “elderly patients” who came to a hospital in Connecticut complaining of confusion. All four tested positive for coronavirus but only two of them ever needed oxygen. This may be an exception to the rule but it is apparently possible that you can have coronavirus and the most serious symptom can be related to your brain rather than your lungs.

It’s worth noting that the unusual cases described in this story mostly involve older patients. The woman in Detroit was 58 years old. The man in Florida was 74. So this appears to be further proof the coronavirus is especially dangerous to the health of older people.

This report from Taiwan dated March 9 mentions two additional cases of coronavirus related encephalitis, one in China and one in Japan.