Question

Please answer true or false. Words cannot be changed or added in to make it true or false.

1. Listeria monocytogenes: Gram-positive, motile rods, ubiquitous and non-sporeforming
2. Listeriosis (~25% mortality rate): usually diagnosed from blood sample or cerebrospinal fluid.
3. Septicemia, meningitis, encephalitis: systemic listeriosis, In pregnant women: abortion and neonatal listeriosis.
4. Listeria cells invade intestinal cells.
5. Listeria outbreak is usually coming from ready to eat food
6. Acriflavine in listeria enrichment broth is major active compound against Proteous, Staphylococcus and fungus.
7. Esculin in Oxford medium is a chromogenic compound to isolate listeria spp.  
8. Oxford medium contains high concentration of sodium chloride and lithium chloride.
9. Listeria is esculin hydrolyzing bacteria. A hydrolyzed product binds with a ferrous salt which shows black precipitation.
10. Phenylethanol in LPM agar is bacteriostatic for Gram-negative bacteria and inhibits DNA synthesis.   
11. Enzymatic cleavage of X-phos-inositol leads to turquoise colonies of Listeria spp. easy to enumerate.
12. Listeria monocytogenes and pathogenic Listeria ivanoviiare then further differentiated by their ability to produce the phospholipase enzyme, phosphatase.
13. Multiplex PCR can be a useful tool to detect multi-Listeriaspp.
14. Vibrio: Gram-negative, motile rods.
15. Origin of Vibrio is almost exclusively marine or estuarine.
16. Food borne illness of Vibrio is related with consumption of seafood (fish, shellfish), potable water or foods that have come into contact with seafood or marine source.
17. Vibiro parahaemolyticusis a most common Vibrio human pathogen.
18. Vibrio vulnificusshows most severe illness.
19. Vibrio vulnificus: leading cause of death in US due to seafood consumption. Usually associated with West Coast oysters
20. Vibrio cholera: not common in US.
21. Vibriousually found in shallow sea waters.
22. Vibrio in winter survives in sediment, resuscitate in spring and grow to high numbers in summer.
23. Vibrio cannot tolerate hydrostatic pressure processing.
24. Vibrio parahaemolyticuscauses beta-hemolysis of human blood cells on Wagatsuma’s agar medium.
25. Wagatsuma’s agar medium has a low salt concentration.
26. Vibriosis (Vibrio parahaemolyticus): everyone is susceptible
27. Symptoms of vibriosis may appear in 16 h (3-76 h range) and last 1-8 days.
28. Vibrio: implicated in numerous outbreaks associated with raw oysters, also implicated in outbreaks related to seaweed, palm fruit, and frozen coconut milk
29. Vibrio vulnificusshow seasonal prevalence (15-22°C, 59-72°F)
30. Vibrio vulnificusis very invasive in soft tissues – intestines, wounds
31. Higher infection rate of Vibrio vulnificuson middle-aged men with liver problems with high iron levels
32. Adding condiments to raw oysters does not offer good protection against Vibrio vunificus.
33. TCBS can be used for the selective isolation Vibrio parahaemolyticus.
34. Vibrio parahaemolyticuscannot ferment sucrose in TCBS.
35. Bromothymol blue is a pH indicator in TCBS.
36. Sodium citrate maintains high pH in TCBS.
37. Vibrio spp. do not produce hydrogen sulfide
38. Vibrio parahaemolyticusforms a green colony on TCBS.
39. Vibrio choleraeforms a yellow colony on TCBS.
40. Vibrio cholerae can grow without salt
41. Vibrio parahaemolyticuscannot ferment cellobiose.  
42. Vibrio vulnificuscannot grow at 0% NaCl.
43. Vibro vlunificusreduce tellurite to form tellurium.
44. Polymyxin B in mCPC inhibits growth of Pseudomonas aeruginosa, and Acinetobacter.
45. Yersinia is Gram-negative rod belonging to Enterobacteriaceae family
46. Yersinia produce heat-stable enterotoxin
47. Yersinia may mimic appendicitis
48. Yersinia are able to ferment mannitol

Answer 1

1. Listeria monocytogenes: Gram-positive, motile rods, ubiquitous and non-sporeforming- TRUE
2. Listeriosis (~25% mortality rate): usually diagnosed from blood sample or cerebrospinal fluid.- TRUE
3. Septicemia, meningitis, encephalitis: systemic listeriosis, In pregnant women: abortion and neonatal listeriosis.-TRUE
4. listeria cells invade intestinal cells- TRUE
5. Listeria outbreak is usually coming from ready to eat food- TRUE