South Asian Journal of Research in Microbiology

Plague is a contagious disease caused by the zoonotic bacteria, (Yersinia pestis) but transmitted by fleas. It is found on rodents and their fleas. The most common ways for humans to contract plague are through handling a plague-infected animal or by getting bitten by a rodent flea that is carrying the pathogen. Septicemic, pneumonic, and bubonic plague are the three most prevalent types. The bubonic plague typically takes 2 to 8 days to incubate. Patients experience weakness, one or more enlarged, painful lymph nodes, headache, chills, and fever (called buboes). The bite of an infected flea results in plague, which is the most widespread type of plague. Pneumonic plague, a more severe form of bubonic plague, can progress and disseminate to the lungs. Septicemic plague incubation period isn’t exactly known but, it most likely happens within days of exposure and is accompanied by high temperature, chills, intense exhaustion, stomach discomfort, shock, and maybe, bleeding into the skin and other organs. Pneumonic plague often only takes 1 to 3 days to incubate and is accompanied by a fever, headache, weakness, rapidly progressing pneumonia, shortness of breath, chest pain, coughing up occasionally bloody or watery mucus, and other symptoms. Generally, fever, chills, headaches, and nausea are some of the general plague symptoms. There is also the case of lymph nodes enlargement, coughing, chest pain, and hemoptysis. Plague can be transmitted through; bites by fleas, contact with contaminated fluid or tissue, and infectious droplets. The symptoms of plague are typically non-specific; hence laboratory investigation is necessary for a certain diagnosis. Y. pestis infection can be detected using a microscope and by bacteria culture. The sample (buboes) can be gotten from blood, mucus (sputum), or an aspirate taken from swollen lymph nodes. Polymerase chain reaction (PCR), can also be employed to diagnose plague (F1 capsule antigen). It is also possible to identify plague by using blood tests that look for antibodies to Y. pestis. Plague can be prevented by eliminating rodent’s habitats around living houses, workplace, and leisure locations, and elimination of bushes, rock piles, garbage, cluttered firewood, and potential rodent food sources such as pet and wild animal food. Plague vaccines are only recommended for high-risk categories such as laboratory professionals who are constantly exposed to the risk of contamination, and health care workers. All forms of plague respond to antibiotic treatment if they are diagnosed early. Those suspected to have made contact with infected patients or animals should be isolated and observed. Plague remains one of the most infectious diseases worldwide. Although as at the time of this review, there is no recent case of plague in Nigeria, or in Africa, effort is still required to create robust awareness among the population on the subject of plague. The focus of this review is to educate and create more awareness among the citizens on plague as a highly infectious disease.