[Skip to Navigation]
March 1986

An Outbreak of Type 4b Listeria monocytogenes Infection Involving Patients From Eight Boston Hospitals

Author Affiliations

From the Bacterial Diseases Division and Hospital Infections Program, Center for Infectious Disease, Centers for Disease Control, Atlanta (Dr Ho); Emory University School of Medicine, Atlanta (Dr Shands); Montefiore Hospital, Albert Einstein College of Medicine, Bronx, NY (Dr Friedland); Massachusetts State Department of Public Health, Boston (Mr Eckind); and Swarthmore (Pa) College (Dr Fraser). Dr Ho is now with the Department of Medicine, New England Medical Center, Boston.

Arch Intern Med. 1986;146(3):520-524. doi:10.1001/archinte.1986.00360150134016

• During September and October 1979,23 patients admitted to hospitals in the Boston area had systemic Listeria monocytogenes infection. Twenty (87%) of these isolates were L monocytogenes type 4b, whereas only nine (33%) of the isolates serotyped during the preceding 26 months had been 4b. Patients with type 4b Listeria infection during the epidemic period (case patients) differed from patients with sporadic Listeria infection in the preceding two years in that more of the case patients had hospital-acquired infection (15/20 vs 4/18), had received antacids or cimetidine before the onset of listeriosis (12/20 vs 3/18), and had gastrointestinal tract symptoms that began at the same time as fever (17/20 vs 4/18). In addition, more case patients took antacids or cimetidine compared with patients matched for age, sex, and date of hospitalization (12/20 vs 10/40). Three foods were preferred by case patients more frequently than by control patients: tuna fish, chicken salad, and cheese. However, the only common feature appeared to be the serving of these foods with raw celery, tomatoes, and lettuce. The raw vegetables may have been contaminated with Listeria, which was able to survive ingestion because of gastric acid neutralization and subsequently to cause enteritis, bacteremia, and meningitis in susceptible hosts. However, we cannot exclude pasteurized milk as a source of this outbreak.

(Arch Intern Med 1986;146:520-524)

Add or change institution