Yersinia Pestis

My microbiology term project. I rock

1. Septicemic Plague Yersinia pestis Bubonic Plague Pneumonic Plague By: Andrea Robertson

2. Gram negative proteobacteria that causes Bubonic Plague Rod-Shaped Facultative Anaerobe

3. Transmission Bubonic plague is a serious, life-threatening disease, which is transmitted to humans when they are bit by an infected rat flea and causes death quickly. There are more than 100 species of fleas that have been reported to naturally be infected with the plague. Y. pestis is mostly found in rats but have also been found in other wild animals such as prairie dogs.

4. Global Significance Researches have found that the plague causes more infections after warmer spring months and wetter summer months. The World Health Organization reports 1-3,000 cases of plague each year. 1 in 7 people die from the disease. People under 20, especially men are more likely to get the plague.

5. The first known pandemic was in 542AD and lasted about 60 years. This outbreak killed millions of people and most of the deaths were located in people living along the Mediterranean Sea. The second pandemic was in the 14 th century. This was believed to be the worst outbreak of plague. It was known as the Black Death. This pandemic was located in central Aisa and lasted for 400 years. Villages were demolished and about a third of the European population died. The third pandemic was in 1894 and started in China and reached Canton and Hong Kong. The plague started spreading throughout the world and killed millions.

6. Bubonic Plague is an infection of the lymph nodes in the Lymphatic system which includes the tonsils, adenoids, spleen and thymus. Glands that swell are called buboes, which is how Bubonic Plague got it’s name. Buboes are found in the groin, armpit or neck and most often will occur close to the site of the initial infection and become red and swollen. Bubonic Plague

7. Bubonic Plague is the most common. Transmitted from the bite of an infected flea or rodent. Symptoms usually occur within 3 to 7 days of exposure. Pain may occur before the actual swelling begins. If bacteria is left untreated it can spread into the bloodstream and symptoms of septicemic plague may begin. More symptoms include: chills, seizures and weakness.

8. Infection in the blood. Bacterium replicate in the bloodstream. It can spread to other organs including the liver, kidneys, spleen and lungs. Transmission from a flea, rodent bite, or if bubonic plague is left untreated. Symptoms include fever, chills, abdominal pain, rapid heart rate, vomiting, delirium, shock, and bleeding into the skin or organs. Fingers, toes, and the nose may become gangrenous. Septicemic Plague

9. Symptoms of Septicemic Plague The “Black Death”

10. Pneumonic Plague is an infection of the lungs and is the most serious of the three plagues yet the least common. Yersinia pestis infects a person’s lungs and leads to pneumonia. Infection happens if a person inhales the plague bacteria from an infected person or animal and is highly contagious. Pneumonic Plague

11. Symptoms usually occur 2 to 3 days after the exposure to the airborne particles of the bacteria. Death usually occurs within 2 to 6 days after symptoms begin. Early treatment of pneumonic plague is necessary to reduce the chances of death. About 10% of people with bubonic plague will get pneumonic plague.

12. Diagnosing Plague A diagnosis can be made from samples of blood, urine, sputum and aspirates of lymph nodes. Chest X-rays and antigen testing are done. A doctor will rule out any other diseases that have similar symptoms such as Syphilis, Tularemia and Shingellosis . Medical professional will listen to a person’s lungs and examine the skin. Under a microscope the bacillus will look like a safety pin.

13. Treatment Treatment for all three plagues is similar. A person who has bubonic or septicemic plague needs to be isolated and the local and state health departments need to be notified. If a patient has pneumonic plague they need to be isolated until sputum cultures come back showing no infection. Antibiotics need to be administered within 24 hours intravenously for at least 10 days. The most common antibiotic used to treat plague is Streptomycin. Streptomycin is given as follows: 30mg/kg/day IM in 2 divided doses for 10 days. Alternative antibiotics such as Gentamicin , Tetracycline, Chloramphenicol and trimethoprim / sulfamethoxazole are also effective.

14. People traveling to areas where plague has been a problem should apply an insect repellent containing DEET ( a versatile repellent that is used worldwide and repels mosquitoes, ticks, fleas, biting fleas and chiggers. People should avoid sick or dead animals and report such animals to a local health department. People who hunt should wear protective gloves when skinning animals. Treating pets (cats or dogs) for fleas on a regular basis. Antibiotics are suggested for a person who has been in contact with a person infected with plague. Prevention

15. Ring around the rosy, Pocketful of posies, Ashes! Ashes! We all fall down! 1665 The words to the ring around the rosy children’s game have their origin in English history. The historical period dates back to the Great Plague of London in 1665. The symptoms of the plague included a rosy red rash in the shape of a ring on the skin (Ring around the rosy). Pockets and pouches were filled with sweet smelling herbs (or posies) which were carried due to the belief that the disease was transmitted by bad smells. The term “Ashes Ashes” refers to the cremation of the dead bodies!

16. The End