Enterobacteriaceae: Genus- Yersinia
27 October 2020 22:17
The Enterobacteriaceae: Genus - Yersinia
Genus Yersinia contains 17 species and only 3 of those species are pathogenic to humans or animals.
1. Yersinia. Enterocolitica
Self-limiting gastroenteritis
2. Yersinia. Pseudotuberculosis
Self-limiting gastroenteritis usually without diarrhoea, rare but more likely to become systemic.
These two yersinia species is transmit infection through food and water borne transmission routes.
3. Yersinia. Pestis
Pneumonic and bubonic plague
This infection is flea-based transmission. This infection has a large impact on society (bubonic plague
pandemic).
Characteristics of Yersinia:
- Non-motile at 37 degrees Celsius (motile below 30 degree Celsius except Y. pestis which is
non-motile.)
- Optimum growth 28-29 degrees Celsius.
Y.enterocolitica/ pseudotuberculosis disease and impact
• Around 100 cases/ year caused by foodborne infection worldwide, low mortality rate.
• Self-limiting acute gastroenteritis and mesenteric lymphadenitis that mimics acute
appendicitis.
Symptoms: Fever, vomiting, abdominal pain (localised to right hand side), diarrhoea.
• Most common in individuals under the age of 7.
• Rare systemic or rheumatologically (joint) complications.
Treatment:
○ Usually self-limiting - supportive care only
○ Antibiotics on occasion of sepsis (e.g. fluoroquinolones)
Y.pestis: impact
• Causative agent of plague
• Huge impact on society since 6th century
• 100s of millions have died
• Historically caused major pandemics e.g. Justinian's Plague (6–8th centuries) and Black Death
(14–18th centuries). The black death killed 30-50% of the country's population (England )
Black Death (1347-1352):
○ Originated in Asia and spread to the Crimea, then Europe and Russia.
○ A quarter of Europe's population were killed (25 million).
○ Today, WHO reports 1-2,000 cases per year globally (8-10% mortality)
○ Most of the infection occurred via human-rodent transmission.
Plague exists as a disease of wild rodents and can be transmitted to human by fleas
E-Yersinia Page 1
27 October 2020 22:17
The Enterobacteriaceae: Genus - Yersinia
Genus Yersinia contains 17 species and only 3 of those species are pathogenic to humans or animals.
1. Yersinia. Enterocolitica
Self-limiting gastroenteritis
2. Yersinia. Pseudotuberculosis
Self-limiting gastroenteritis usually without diarrhoea, rare but more likely to become systemic.
These two yersinia species is transmit infection through food and water borne transmission routes.
3. Yersinia. Pestis
Pneumonic and bubonic plague
This infection is flea-based transmission. This infection has a large impact on society (bubonic plague
pandemic).
Characteristics of Yersinia:
- Non-motile at 37 degrees Celsius (motile below 30 degree Celsius except Y. pestis which is
non-motile.)
- Optimum growth 28-29 degrees Celsius.
Y.enterocolitica/ pseudotuberculosis disease and impact
• Around 100 cases/ year caused by foodborne infection worldwide, low mortality rate.
• Self-limiting acute gastroenteritis and mesenteric lymphadenitis that mimics acute
appendicitis.
Symptoms: Fever, vomiting, abdominal pain (localised to right hand side), diarrhoea.
• Most common in individuals under the age of 7.
• Rare systemic or rheumatologically (joint) complications.
Treatment:
○ Usually self-limiting - supportive care only
○ Antibiotics on occasion of sepsis (e.g. fluoroquinolones)
Y.pestis: impact
• Causative agent of plague
• Huge impact on society since 6th century
• 100s of millions have died
• Historically caused major pandemics e.g. Justinian's Plague (6–8th centuries) and Black Death
(14–18th centuries). The black death killed 30-50% of the country's population (England )
Black Death (1347-1352):
○ Originated in Asia and spread to the Crimea, then Europe and Russia.
○ A quarter of Europe's population were killed (25 million).
○ Today, WHO reports 1-2,000 cases per year globally (8-10% mortality)
○ Most of the infection occurred via human-rodent transmission.
Plague exists as a disease of wild rodents and can be transmitted to human by fleas
E-Yersinia Page 1
