Part:BBa_K3289014

Yersinia Pestis is a rod shaped, Gram-negative coccobacillus bacteria. It has no spores and is nonmotile once inside a host. Y. Pestis is a very dangerous type of bacteria as it is the cause of Bubonic plague, Septicemic plague, and Pneumonic plague, which are all infectious, life-threatening diseases if not treated properly.

Major Concerns and Geographical prevalence:

Y. Pestis has been the cause of 3 major epidemics in the past, the most notable one being “the Black Death”, where a third of the population of Europe were killed during the 14th century. Nowadays, the plague is not that common; they can still be found in regions in Africa such as the Democratic Republic of the Congo and Madagascar. The World Health Organization reported 3248 cases of the plague from 2010 to 2015, including 584 deaths.

Although the plague is not the most relevant disease, Y. Pestis has been reported to be a potential bioweapon to be used for bioterrorism. The Pneumonic form of the disease can kill within 24 hours of infection, and the disease has a mortality rate of almost 100%. Therefore, rapid detection techniques for diagnosis of the pathogen are essential in case of a breakout.

Infection and Transmission:

The plague is an animal disease and can be found in all continents except Oceania. Humans are at risk of infection wherever there exists animals that have the disease and vectors that can transmit the disease. The main vector of the disease is the oriental rat flea- a parasite that feeds on rodents. The oriental rat flea is very small in size, ranging from 1/16 to 1/8 of an inch. After having fed on an infected rodent, the oriental rat flea can transmit the bacteria to humans by feeding on the human targets.

Once infected, human to human transmission of the bacteria can happen in two ways. The first being direct contact with infectious body fluids or contaminated material. The second being in the case of Pneumonic plague, where a person can get infected by the inhalation of droplets from an infected patient.

Symptoms of Infection:

Bubonic plague:

Development of inflamed, red, painful lymph nodes called “buboes”, which develop rapidly near insect bites. Fever, muscle pain, headache and extreme weakness can occur 2-6 days after an insect bite. If untreated, it can lead to the septicemic plague.

Septicemic plague:

This form of plague results when the bacteria enters the bloodstream and causes septicemia. Symptoms include nausea, muscle pain, vomiting, diarrhea, bruise development, bleeding problems (skin, nose, mouth, rectum, urine), drops in blood pressure, high pulse, kidney failure, breathing problems and possibly death.

Pneumonic plague:

This form of plague occurs when the bacteria enters the lungs and causes pneumonia. Symptoms include headaches, pain in the chest, fever, cold, increased breathing rate, shortness of breath, and coughing blood. Without treatment, the disease can cause death.

Target Gene for Detection:

YPO2088: Gene specific to Y. Pestis. Protein coding gene that makes the enzyme methyltransferase. The enzyme moves methyl groups from one compound to another.