A Skunk, a Bat Virus and a Kidney: How Rabies Passed Through an Organ Transplant, 2024–2025

Rabies usually spreads through the bite or scratch of an infected mammal, and without timely post-exposure prophylaxis (PEP) it is almost always fatal. But it has also passed from person to person through organ and tissue transplants: from 1978 to 2013, three such events in the United States affected nine recipients. This is the story of the fourth.

The kidney recipient

In December 2024, an adult man from Michigan received a left kidney from an Idaho donor at a hospital in Ohio.

CDC found rabies virus RNA in his saliva, a skin biopsy from the back of his neck, and brain tissue, and rabies antibodies in his blood. The virus was the silver-haired bat (Lasionycteris noctivagans) variant. His family reported no animal exposures. CDC was notified on January 27, 2025.

Clinical course, testing and investigation timeline, November 2024–February 2025. CDC

The donor

Interviews with the donor's family filled in what the questionnaire hadn't.

• In late October 2024, a skunk approached the donor as he held a kitten in an outbuilding on his rural property. In the struggle, which left the skunk unconscious, he got a scratch on the shin that bled. He didn't think he had been bitten, and put the skunk's behavior down to it hunting the kitten.
• About 5 weeks later, in early December, he became confused, had trouble swallowing and walking, hallucinated and had a stiff neck. Two days later he was found unresponsive at home after a presumed cardiac arrest. He was resuscitated but never regained consciousness, and was declared brain dead on hospital day 5.
• His left kidney, heart, lungs and both corneas were recovered for donation.

The hospital had not known about the skunk scratch and attributed his symptoms to long-standing health problems. Rabies isn't part of routine donor testing, because it is so rare in U.S. patients and so complex to diagnose.

Once rabies was suspected, his stored blood from his third hospital day tested negative for rabies antibodies. But a weeks-long search turned up kidney biopsy samples, and in the right kidney's sample CDC found rabies RNA of the same silver-haired bat variant — confirming the infection came from the donated organ. (The left kidney's sample was too small to test.)

How it likely happened: skunks are not a rabies reservoir in Idaho, but bat-borne variants, including the silver-haired bat variant, circulate there. The investigators think a rabid bat infected the skunk, the skunk infected the donor, and the kidney infected its recipient.

The other tissues

Finding everyone exposed

Rabies can pass when saliva, tears or nerve-containing tissue from an infected person or animal touches broken skin or mucous membranes. Investigators looked for anyone in contact with the skunk, the donor or the recipient from 14 days before symptoms until death and decontamination.

No other people or animals were exposed to the skunk. Whether everyone advised to get PEP did so is not known.

What the record shows about PEP

Across all four U.S. transplant-rabies events, 13 recipients were involved: the seven who did not get PEP died, and all six who did survived. Worldwide, PEP has failed in two of 21 organ and tissue recipients — one who started but didn't finish the series, and one for unclear reasons. Removing the corneas as well may have reduced risk further: corneas lie close to the optic nerves and the brain, which raises worries about a shorter incubation period, and they are far easier to remove than a life-sustaining organ.

Lessons

• Overall, the risk of catching any infection from a transplant, rabies included, is low.
• There is no standard guidance for transplant teams on donors' animal exposures. CDC, the Health Resources and Services Administration and partners are reviewing them.
• If a potential donor — especially one with acute encephalopathy — was bitten or scratched by a rabies-susceptible animal in the past year, transplant teams should consider consulting public health officials.
• That consultation can happen before or shortly after transplantation. Rabies usually incubates for weeks to months, and PEP decisions are urgent but not emergencies. If a donor is suspected of rabies after the fact, a quick risk assessment can speed testing, possible removal of the graft, and PEP for recipients and contacts — and save lives.

Sources

Based on Earnest R, Carter KK, Margrey SF, et al., "Human-to-Human Rabies Transmission via Solid Organ Transplantation from a Donor with Undiagnosed Rabies — United States, October 2024–February 2025," MMWR volume 74, number 39, Centers for Disease Control and Prevention, with authors from CDC and state and local health departments in Idaho, Ohio, Michigan, California, Maryland, Missouri, New Mexico and Washington, and the University of Toledo; a work of the United States government in the public domain.