Fecal Microbiota Transplants Could Spread Monkeypox, FDA Warns

Patients who undergo fecal transplants may face an increased risk of contracting monkeypox, according to a new warning issued by federal health officials.

The U.S. Food and Drug Administration (FDA) issued a safety alert on August 22, indicating that doctors and patients should be aware that monkeypox may be spread through fecal microbiota transplantation (FMT), resulting in a call for safety precautions to be taken.

A monkeypox has struck multiple countries since May, including the United States, involving a disease that is spread through close contact with infected, symptomatic people.

According to the FDA, recent studies document the presence of the monkeypox virus in rectal swabs and stool samples from infected individuals. Another study indicated rectal swabs from people without symptoms also contained the virus. This data indicates it may be possible for the virus to be transmitted through fecal transplant.

There is currently a test to detect monkeypox from swab samples taken from lesions, but not from stool. So, the true risk of contracting monkeypox from fecal transplant is unknown.

Fecal Transplant Infection Risks

Fecal transplants involve the use of stool from healthy donors transferred to the gastrointestinal tract of other patients suffering from various health concerns, including Clostridium difficile. Fecal transplants are intended to introduce healthy bacteria into the intestinal tract to replenish good bacteria. In some cases, fecal transplants can pose a risk to recipients.

“Whether, and the extent to which, monkeypox virus can be transmitted through feces or from asymptomatic infected individuals is not known,” the FDA said in the recent safety alert.

The procedure has been known to carry the risk of spreading infectious diseases, according to the FDA.

A case study from  2019 indicated two fecal transplant patients contracted E. coli bacteria from a fecal stool donor, leading to the death of one patient.

In 2020, the FDA issued a warning about fecal transplants indicating the procedure can cause serious infections in the recipients. Six serious illnesses were linked to fecal transplants, resulting in one death. To that end, the FDA issued new safety precautions for fecal transplants amid the COVID-19 pandemic. The pandemic may leave patients susceptible to coronavirus transmission if the stool is not properly screened.

Fecal Transplant Safety Protocols

The FDA is recommending additional protections for fecal transplant protocols if it involves stool donated after March 15, 2022. The agency recommends implementing enhanced donor screening with questions focusing on monkeypox risk, criteria to exclude donors based on screening, and informed consent including information about transmission of monkeypox via FMT.

The FDA urges all doctors and patients to report any suspected side effects related to fecal microbiota transplantation products to the FDA’s MedWatch Adverse Event Reporting Program.