A patient who contracted and died of rabies earlier this month in Maryland contracted the disease after a kidney transplant a year earlier, the federal Centers for Disease Control and Prevention announced on Friday.

“The patient was one of four people who had received an organ from the same donor,” the CDC said in a statement. “Other patients who received organs from same donor getting anti-rabies shots. The donor was from Florida and organs were sent to patients in Florida, Georgia, Illinois, and Maryland.

In early March, the Maryland Department of Health and Mental Hygiene launched an investigation after the patient died, which led to the rabies diagnosis. The patient hadn’t had any reported bites from animals; rabies, nearly always fatal if untreated, is most often transmitted from bites from infected animals.

Advertisement - Continue Reading Below

“At the time of the donor’s death, rabies was not suspected as the cause and testing for rabies was not performed,” the CDC stated. Organs typically aren’t screened for rabies unless the donor is known to have been exposed and the CDC called transplant-related transmission of rabies “extremely rare.”

The CDC’s preliminary laboratory analysis indicates that the recipient and the donor both had the same type of rabies virus-a raccoon type. This type of rabies virus can infect not only raccoons, but also other wild and domestic animals. In the United States, only one other person is reported to have died from a raccoon-type rabies virus. Fewer than five rabies cases are diagnosed every year in the U.S.

Rabies infects the central nervous system, ultimately causing disease in the brain and death. Initial symptoms include fever, headache, and general weakness or discomfort, which progress without treatment to more specific symptoms that include insomnia, anxiety, confusion, partial paralysis, hallucinations, agitation, and increased saliva production.

Potential organ donors are screened for a variety of infectious diseases including hepatitis and HIV, but rabies isn’t one of them. A 2010 workshop convened by the US Food and Drug Administration estimated that transmission of infectious diseases to organ recipients occurs about one percent of the time.