HARTFORD, Conn. (AP)– A 7-week-old baby who died at a hospital in the Hartford area had the coronavirus, Connecticut Gov. Ned Lamont said Wednesday. The cause of death is unknown.

The unidentified child from Hartford was unresponsive when taken to the hospital recently and could not be revived. The infant tested positive during a postmortem exam for the virus that causes COVID-19, said Josh Geballe, the governor’s chief operating officer.

Dr. James Gill, the state’s chief medical examiner, said the infant had no other known medical conditions. An autopsy has been done but more tests are needed before a cause of death can be determined, he said.

“That baby was less than 7 weeks old. And just a reminder that nobody is safe with this virus,” Lamont said at a news conference after touring a temporary hospital set up at Southern Connecticut State University.

Children have made up a small fraction of coronavirus cases worldwide.

A letter published in the New England Journal of Medicine by Chinese researchers last month reported the death of a 10-month-old with COVID-19. The infant had a bowel blockage and organ failure and died four weeks after being hospitalized.

Separate research published in the journal Pediatrics traced 2,100 infected children in China and noted one death, a 14-year old. The study found less than 6% of children were seriously ill.

For most people, the coronavirus causes mild or moderate symptoms, such as fever and cough that clear up in two to three weeks. For some, especially older adults and people with existing health problems, it can cause more severe illness, including pneumonia, and death.

More than 43,000 people have died from the virus, while more than 185,000 have recovered.