Bacteria Affect Seafood Quality and Safety (part 3) Brian Himelbloom, PhD University of Alaska Fairbanks School of Fisheries and Ocean Sciences Kodiak Seafood and Marine Science Center Kodiak, AK 99615 bhhimelbloom@alaska.edu 1
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Clostridium species Gram-positive Spore-forming Anaerobic Curved or straight bacilli >100 species Most have flagella 3
Clostridium species Soils, freshwater and marine sediments, intestinal tract of humans and animals 4
C. botulinum Identified in late 1800's Relatively rare but often fatal Seven types: Type E seen mainly in marine products 5
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C. botulinum Symptoms: Onset of illness 12-72 hours Paralysis of nerves and muscles in face, head, throat & extremities Death due to respiratory failure Patients require antitoxin and intensive respiratory care 7
C. botulinum Control measures: Adequate time-temperature processing for retorted products Water-phase salt concentrations for inhibition Temperature control for vacuumpackaged products 8
Listeria species Gram-positive Non-spore-forming Facultatively anaerobic Short bacilli 7 species Motile 9
Listeria species Soils and decaying vegetation Cold-tolerant Salt-tolerant 10
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L. monocytogenes Identified in late 1920's Relatively rare but often fatal to immunocompromised people 12
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L. monocytogenes Symptoms: Onset of illness 1 day to weeks Meningitis, encephalitis or septicemia in non-pregnant adults, elderly and immunocompromised patients In pregnant women, flu-like illness may result in stillbirth or spontaneous abortion 14
L. monocytogenes Control measures: Adequate pasteurization process Prevent cross-contamination of ready-toeat products Use Listeria-specific sanitation procedures Environmental testing program 15
Vibrio species Gram-negative Straight or curved bacilli Facultatively anaerobic Motile Halophilic >30 species 16
Vibrio species First incidences of cholera and identified bacteriologically in 1800's Natural inhabitants of brackish and salt water worldwide, primarily tropical seawater 17
Pathogenic Vibrio species Symptoms: Onset of illness 8-72 hours Gastroenteritis infections from V. cholerae range from no fever to mild to severe 18
Pathogenic Vibrio species Control measures: Testing of raw seafood susceptible to vibrios Pasteurization 19
Scombroid (Histamine) Poisoning Microorganisms growing on certain types of fish to produce histamine (chemical) 20
Scombroid (Histamine) Poisoning Scombroid fish (tuna, mackerel) and non-scombroid fish (herring, mahi-mahi) Primarily through growth of enteric-related bacteria 21
Symptoms: Scombroid (Histamine) Poisoning Mild illness and short duration Skin rash and facial flush, itching, tingling and burning sensations, nausea, vomiting and diarrhea Can be confused with food allergies 22
Scombroid (Histamine) Poisoning Control measure: Prevent onboard temperature abuse of scombroid species 23
Staphylococcus species Gram-positive cocci Non-motile Non-spore-forming Facultative anaerobe Over 30 species 24
Staphylococcus species Widespread in nature Found on skin, skin glands and mucous membranes of animals and humans Salt-tolerant 25
S. aureus Symptoms: Vomiting, abdominal pain and diarrhea within 1-6 hours (no fever) 26
S. aureus Control measures: Prevent hand contamination of ready-to-eat products Pasteurization Water activity <0.85 27
Salmonella species Gram-negative Non-spore-forming Motile or non-motile Facultatively anaerobic rods 28
Salmonella species Discovered in early 1900 s Widely distributed on plants, in soil, water and intestines of humans and animals 29
Salmonella species Symptoms: Onset of illness 8-72 hours Infections ranging from mild gastroenteritis (2-7 days) to lifethreatening fever 30
Salmonella species Control measures: Personnel sanitation Pasteurization 31