Plague is an infectious disease caused by a zoonotic bacteria that is commonly found in small mammals and their fleas. It is spread between animals via fleas. Plague affects animals; in rodents, plague usually causes mild illness but can be fatal during population outbreaks. Wild carnivores infected with the disease usually do not appear sick. Cats and other animals can develop fever, swollen lymph nodes, internal abscesses, or die suddenly. Bubonic plague symptoms include swollen lymph nodes, fever, inflammation, depression, vomiting, dehydration, diarrhoea, enlarged tonsils, and anorexia. The dog's head and neck will swell significantly, and if it survives, its lymph nodes may abscess, rupture, and drain. Plague bacteria are typically transmitted through the bite of an infected flea. Many rodents die during plague outbreaks, causing hungry fleas to seek other blood sources. People and animals who visit areas where rodents have recently died from plague are at risk of contracting the disease through flea bites. Bubonic and septicemic plague are typically spread by flea bites or handling an infected animal, whereas pneumonic plague is typically spread between people via infectious droplets in the air.