A team of researchers says a relatively new foodborne pathogen documented in a man who had eaten raw salmon before becoming ill is all the evidence needed to warn the public against consuming raw seafood.
“This case highlights the importance of preventing seafood-associated infections and the need to consider rare human pathogens in elderly or immunocompromised, marine-exposed populations, as well as persons who might consume at-risk food that might have been imported from outside the United States and persons who might have been infected outside the United States when traveling,” according to research reported on by the CDC’s Morbidity and Mortality Weekly Report.
Made up of scientists from academic institutions from coast to coast, the team reviewed the case of an 87-year-old man who was treated in a Flushing, NY, emergency department a year ago. Doctors diagnosed appendicitis and used laboratory tests to determine he had an infection caused by Shewanella haliotis.
The patient was the first documented case of Shewanella haliotis infection in the Americas. The illness was the first ever documented case of the organism infecting a patient’s appendix, according to the researchers.
“S. haliotis is an emerging human pathogen, first isolated from abalone gut microflora in 2007,” according to the report. “The geographic distribution of human infections caused by S. haliotis is concentrated in Asia, with most reports coming from China, Japan, South Korea, and Thailand. No cases of S. haliotis human infections had (previously) been reported in the World Health Organization’s Region of the Americas.”
The bacteria is widespread in marine environments, including broad contamination of cultivated shellfish, according to the researchers.
The patient whose case is highlighted in the report said he art raw salmon 10 days before becoming ill. He did not have any other marine exposures or exposure to ill contacts. His symptoms began within the 3- to 49-day window that is consistent with data on infections from Shewanella haliotis.
The epidemiologic exposure history of the patient supports the link between raw fish consumption and infection, according to the researchers. No other organisms were isolated in this patient.
Some antibiotic resistance has been documented in some isolates of Shewanella haliotis, but the case patient’s strain did not show such resistance. Treatment with intravenous piperacillin-tazobactam while in the hospital and a discharge prescription for oral amoxicillin-clavulanic acid appeared to have resolved the infection when the patient was examined 13 days after leaving the hospital.
Authors on the research are listed as Dakai Liu, PhD; Roberto Hurtado Fiel, MD; Lucy Shuo Cheng, MD; Takuya Ogami, MD; Lulan Wang, PhD; Vishnu Singh; George David Rodriguez, PharmD; Daniel Hagler, MD; Chun-Chen Chen, MD, PhD; and William Harry Rodgers, MD, PhD.
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