Nosocomial Pseudoepidemic Caused by Bacillus cereus Traced to Contaminated Ethyl Alcohol from a Liquor Factory

Abstract

From September 1990 to October 1990, 15 patients who were admitted to four different departments of the National Taiwan University Hospital, including nine patients in the emergency department, three in the hematology/oncology ward, two in the surgical intensive care unit, and one in a pediatric ward, were found to have positive blood (14 patients) or pleural effusion (1 patient) cultures for Bacillus cereus. After extensive surveillance cultures, 19 additional isolates of B. cereus were recovered from 70% ethyl alcohol that had been used as a skin disinfectant (14 isolates from different locations in the hospital) and from 95% ethyl alcohol (5 isolates from five alcohol tanks in the pharmacy department), and 10 isolates were recovered from 95% ethyl alcohol from the factory which supplied the alcohol to the hospital. In addition to these 44 isolates of B. cereus, 12 epidemiologically unrelated B. cereus isolates, one Bacillus sphaericus isolate from a blood specimen from a patient seen in May 1990, and two B. sphaericus isolates from 95% alcohol in the liquor factory were also studied for their microbiological relatedness. Among these isolates, antibiotypes were determined by using the disk diffusion method and the E test, biotypes were created with the results of the Vitek Bacillus Biochemical Card test, and random amplified polymorphic DNA (RAPD) patterns were generated by arbitrarily primed PCR. Two clones of the 15 B. cereus isolates recovered from patients were identified (clone A from 2 patients and clone B from 13 patients), and all 29 isolates of B. cereus recovered from 70 or 95% ethyl alcohol in the hospital or in the factory belonged to clone B. The antibiotype and RAPD pattern of the B. sphaericus isolate from the patient were different from those of isolates from the factory. Our data show that the pseudoepidemic was caused by a clone (clone B) of B. cereus from contaminated 70% ethyl alcohol used in the hospital, which we successfully traced to preexisting contaminated 95% ethyl alcohol from the supplier, and by another clone (clone A) without an identifiable source.

Comparison of PCR-RFLP, ribotyping and ERIC-PCR for typingBacillus anthracisandBacillus cereusstrains

“…Bacillus anthracis causes anthrax and represents one of the most molecular monomeric bacteria known. Jackson et al (1997) reported that PCR analysis of 198 B. anthracis isolates revealed a variable region of the vrrA gene sequence, which resulted in ®ve polymorphisms among isolates. In vrrA±RFLP analysis, the unique restriction digestion pattern in all but one strain of B. anthracis con®rmed the clonal nature of this species.…”

“…In view of the need for new, fast and reproducible tools to improve our knowledge of relatedness with B. cereus group bacteria, suitable genes for genotype typing schemes were investigated. The VNTR region located in the B. anthracis vrrA gene sequence can separate all known B. anthracis strains into ®ve categories (Jackson et al 1997). It has also been reported that B. cereus and B. mycoides vary from B. anthracis isolates by 158and 170-nucleotide differences, respectively (Andersen et al 1996).…”

“…A DNA fragment difference among strains was identi®ed from RAPD using M13 primer. This sequence (vrrA gene) contained a 12 bp repeat that was present in different copy numbers to generate polymorphic DNA fragments (Jackson et al 1997). Recently, Keim et al (1997) also detected 31 polymorphic chromosomal regions in 78 B. anthracis isolates using the AFLP (ampli®ed fragment length polymorphism) method.…”

“…The general methodology is referred to as enterobacterial repetitive intergenic consensus±PCR or ERIC±PCR. ERIC±PCR has been applied to type various B. cereus strains (Hsueh et al 1999). However, ERIC±PCR studies have not been done on B. anthracis isolates as far as is known.…”

Epidemiologic Background of Hand Hygiene and Evaluation of the Most Important Agents for Scrubs and Rubs

“…A pseudo-outbreak was reported due to contamination of ethanol with spores of B. cereus. The ethanol was used in the hospital pharmacy for preparation of skin antiseptics without spore filtration (219). Another report described contamination of 70% ethanol with spores of Clostridium perfringens, which was eliminated by addition of 0.27% hydrogen peroxide over 24 h (602).…”