EPA Science Inventory

Acid Resistance in Francisella tularensis

Citation:

Adcock, N. J., B. J. Morris, AND E. W. Rice. Acid Resistance in Francisella tularensis. MicrobiologyOpen. Wiley-Blackwell Publishing, Hoboken, NJ, 3(1):133-138, (2014).

Description:

Journal article

Purpose/Objective:

Francisella tularensis, the etiologic agent of tularemia, can survive under acidic conditions. Tularemia can be acquired by several routes, including by ingestion of contaminated food or water. While acid resistance is usually associated with a low oral infective dose, the infective dose for gastrointestinal illness is quite high. In this study, four strains of F. tularensis ssp. tularensis (type A) and four strains of F. tularensis ssp. holarctica (type B) were examined for innate acid resistance and the ability to survive in synthetic gastric fluid under in vitro conditions similar to passage through the human stomach. Survival for all strains was significantly less in pH 2.5 synthetic gastric fluid than in pH 2.5 phosphate buffered saline and pH 4.0 synthetic gastric fluid. Attenuated strains were consistently less resistant. Type B strains are most often associated with waterborne outbreaks and were examined after storage in natural water. Low nutrient pre-adaptation resulted in increased resistance. Although F. tularensis can persist under certain acidic conditions, it is sensitive to conditions replicating the fasting human stomach. This may help explain the high infective dose required for gastrointestinal infections.

URLs/Downloads:

ACID RESISTANCE IN FRANCISELLA TULARENSIS   Exit

Record Details:

Record Type: DOCUMENT (JOURNAL/PEER REVIEWED JOURNAL)
Start Date: 02/01/2014
Completion Date: 02/01/2014
Record Last Revised: 04/14/2015
Record Created: 09/05/2013
Record Released: 09/05/2013
OMB Category: Other
Record ID: 259755

Organization:

U.S. ENVIRONMENTAL PROTECTION AGENCY

OFFICE OF RESEARCH AND DEVELOPMENT

NATIONAL HOMELAND SECURITY RESEARCH CENTER

WATER INFRASTRUCTURE PROTECTION DIVISION