Overview of Opportunistic Bacteria


  • Ahmed Talib Abdulkarem Ministry of Health. Iraq
  • Ahmed Abbas Hasan College of Pharmacy, University of Kerbala, Kerbala, Iraq
  • Hasan Raheem Khudhur College of Education for Pure Science, Al-Muthanna University. Iraq
  • Saif M. Abed Department of Medical Laboratories, College of Medical and Health Techniques, Sawa University, Samawah, Iraq




Opportunistic bacteria, Predisposing Factors, Foodborne Opportunistic, waterborne Opportunistic, Airborne Opportunistic


The receptive patient and the bacterium serve as the two defining criteria for opportunistic bacteria. Theoretically, no saprophytic or typical commensal microbes can infiltrate a healthy receptive person. Only specific "undesirable" commensal species, "such as Vargues' Specific Pathogenic Bacteria", can infect this person. Several species from the typical commensal flora, or opportunistic bacteria in the wide meaning of the word, “may infiltrate an otherwise healthy host if their immune defences temporarily deteriorate”. Even species that were previously thought to be non-virulent may assault an immunosuppressed patient with a significant and protracted immune system depression, “including various saprophytic and commensal microbes”. Several bacteria that are typically found in water, food, and the air have recently become opportunistic pathogens in both people and animals. The issue is made more difficult by the introduction of many antibiotic-resistant strains of these opportunistic pathogens, which make hospital-acquired infections in susceptible hosts challenging to treat in the setting of illness.