What are Yersiniaceae species?

From the Guidelines

Yersinieae species, particularly Yersinia pestis, require immediate treatment with antibiotics such as ciprofloxacin, levofloxacin, or doxycycline for 7-10 days to prevent high morbidity and mortality rates. These gram-negative bacteria are facultative anaerobes that can be found in various environments, including soil, water, and animals, and are transmitted primarily through flea bites, causing bubonic, pneumonic, or septicemic plague 1. The optimal treatment duration for bubonic plague is unknown, but 10-14 days is probably adequate, and patients with bubonic plague may develop secondary pneumonic plague and should be placed in respiratory isolation until after 48 hours of effective drug therapy 1.

Key Considerations

• Y. pestis is the causative agent of plague, which can be severe and lethal if left untreated
• Immediate treatment with antibiotics is essential to prevent high morbidity and mortality rates
• Ciprofloxacin, levofloxacin, and doxycycline are recommended antibiotics for the treatment of plague, with dosages of 15 mg/kg every 12 hours, 10 mg/kg every 12 hours, and 2.2 mg/kg every 12 hours, respectively 1
• Patients with pneumonic plague should be placed in respiratory isolation until after 48 hours of effective drug therapy
• Breastfeeding mothers with bubonic or septicemic plague can continue to breastfeed their infants if able, but mothers with pneumonic plague should avoid direct breastfeeding until they have received antimicrobial treatment for ≥48 hours and demonstrated clinical improvement 1

Prevention Measures

• Proper food handling and clean water access can help prevent the spread of Yersinieae species
• Flea control and avoiding contact with potentially infected animals are essential in endemic plague areas
• Early recognition and treatment of plague are critical to preventing high morbidity and mortality rates, and rapid diagnostic techniques are essential for early detection 1

From the Research

Yersinieae Species Overview

• The Yersinieae species include Yersinia pestis, Yersinia enterocolitica, and Yersinia pseudotuberculosis, which are all pathogenic bacteria 2, 3, 4, 5.
• Yersinia pestis is the causative agent of plague, a disease that can manifest in three clinical forms: bubonic, septicemic, or pneumonic 2.
• Yersinia enterocolitica is a zoonotic agent that causes gastrointestinal disease in humans, as well as reactive arthritis and erythema nodosum 3.

Genetic Relationships

• A multilocus sequence typing (MLST) scheme has been developed to study the population structure and evolutionary relationships of the three pathogenic Yersinia species 4.
• The MLST analysis showed that Yersinia pestis is a clone that evolved from Yersinia pseudotuberculosis 1,500-20,000 years ago 5.
• Yersinia enterocolitica strains formed a relatively conserved group, with most strains clustering within specific sequence types (STs) 4.

Disease Transmission and Prevention

• Yersinia pestis can be transmitted to humans through the bites of infected fleas or direct contact with infected animals 2.
• Yersinia enterocolitica can be acquired through the consumption of contaminated foods, particularly pork products 3.
• Food safety measures, such as proper handling and cooking of food, can help minimize the risk of human infection with Yersinia enterocolitica 3.
• Patients with plague should be placed in strict isolation for the first 48 hours of treatment to prevent human-to-human transmission 2.