Related Experiment Video
Updated: Jul 30, 2026
Detection and Isolation of Campylobacter spp. from Raw Meat
Published on: February 23, 2024
PCR comparison of Mycobacterium avium isolates obtained from patients and foods
S Yoder1, C Argueta, A Holtzman
1Education and Research Institute, Olive View-UCLA Medical Center, Sylmar, California 91342, USA. sean.yoder@csun.edu
Abstract:
Mycobacterium avium is a cause of disseminated disease in AIDS patients. A need for a better understanding of possible sources and routes of transmission of this organism has arisen. This study utilized a PCR typing method designed to amplify DNA segments located between the insertion sequences IS1245 and IS1311 to compare levels of relatedness of M. avium isolates found in patients and foods. Twenty-five of 121 food samples yielded 29 mycobacterial isolates, of which 12 were M. avium. Twelve food and 103 clinical M. avium isolates were tested. A clinical isolate was found to be identical to a food isolate, and close relationships were found between two patient isolates and two food isolates. Relatedness between food isolates and patient isolates suggests the possibility that food is a potential source of M. avium infection. This study demonstrates a rapid, inexpensive method for typing M. avium, possibly replacing pulsed-field gel electrophoresis.
Insights
Mycobacterium avium (M. avium) infections in AIDS patients may originate from food sources. A new PCR typing method revealed genetic links between M. avium found in food and clinical isolates, suggesting food as a potential transmission route.
Area of Science:
- Microbiology
- Infectious Diseases
- Molecular Biology
Background:
- Mycobacterium avium (M. avium) causes disseminated disease in individuals with Acquired Immunodeficiency Syndrome (AIDS).
- Understanding M. avium transmission routes is crucial for public health interventions.
- Existing typing methods for M. avium may be time-consuming or expensive.
Purpose of the Study:
- To investigate the potential sources and transmission routes of M. avium in AIDS patients.
- To compare the genetic relatedness of M. avium isolates from food and clinical samples.
- To evaluate a novel PCR-based typing method for M. avium.
Main Methods:
- A PCR typing method amplifying DNA between insertion sequences IS1245 and IS1311 was developed.
- M. avium isolates were obtained from food samples and clinical cases of disseminated disease.
- Genetic relatedness was assessed by comparing PCR profiles of 12 food and 103 clinical M. avium isolates.
Main Results:
- Twelve M. avium isolates were identified from 121 food samples.
- One clinical M. avium isolate was identical to a food isolate.
- Close genetic relationships were observed between other patient and food M. avium isolates.
Conclusions:
- Food may serve as a potential source for M. avium infections in immunocompromised individuals.
- The developed PCR typing method is rapid, inexpensive, and effective for M. avium strain differentiation.
- This method shows promise as an alternative to traditional techniques like pulsed-field gel electrophoresis.
