Typhus refers to a group of infectious diseases caused by Rickettsia bacteria and transmitted to humans through arthropod vectors such as fleas, lice, or mites. These diseases, including epidemic typhus, endemic (murine) typhus, and scrub typhus. Globally, murine typhus alone is estimated to cause tens of thousands of infections each year, while large historical outbreaks … Read more
Anaplasmosis is an infectious disease spread by ticks. It is caused by Anaplasma phagocytophilum, a type of bacteria that can only survive inside the cells of its host and is classified as gram-negative (a laboratory term describing its outer cell structure). People become infected mainly through the bite of blacklegged ticks, Ixodes scapularis in the … Read more
Histoplasmosis is an infection caused by breathing in tiny fungal spores from Histoplasma capsulatum, a fungus that grows in soil containing bird or bat droppings. The disease occurs worldwide, including in the Americas, Africa, and Asia, but is especially common in the Ohio and Mississippi River valleys of the United States. Studies show that 60–90% … Read more
Endophthalmitis is a serious inflammation inside the eye, usually caused by bacteria or fungi. It is considered a medical emergency because, without quick treatment, it can cause rapid and permanent loss of vision. The condition most often develops after eye surgeries, especially cataract surgery, where it occurs in about 0.02% to 0.2% of cases worldwide. … Read more
Coxsackievirus infection is an illness caused by a highly contagious group of enteroviruses, which belong to the Picornaviridae family. Enteroviruses are common worldwide and cause many different types of infections. In the United States alone, they are estimated to cause 10–15 million illnesses each year. The Coxsackievirus A and B groups are the most common, … Read more
Myocarditis is a condition in which the heart muscle becomes inflamed. This inflammation can cause a wide range of symptoms, including chest pain, shortness of breath, tiredness, fever, and rapid or irregular heartbeats (called arrhythmias). Some people also develop swelling in the legs or feet (edema) or experience flu-like symptoms such as muscle aches or … Read more
Cryptosporidiosis is a parasitic infection of the digestive system caused by microscopic organisms called Cryptosporidium. The illness usually leads to watery diarrhea, stomach cramps, nausea, vomiting, mild fever, and loss of appetite. The parasite spreads through the fecal–oral route, meaning people become infected when they accidentally swallow food or water contaminated with feces. Common sources … Read more
Schistosomiasis is a long-lasting parasitic infection caused by blood flukes, small flatworms—from the genus Schistosoma. It is one of the world’s most widespread neglected tropical diseases. People become infected when their skin comes into contact with freshwater that contains the parasite’s larvae, called cercariae, which are released by infected freshwater snails. This exposure often occurs … Read more
Ehrlichiosis is a tick-borne illness caused by several species of Ehrlichia, a group of bacteria that must live inside human cells to survive. The main species that infect people are Ehrlichia chaffeensis, Ehrlichia ewingii, and Ehrlichia muris eauclairensis. Infection occurs when an infected hard tick, most commonly the lone star tick (Amblyomma americanum) and, in … Read more
Babesiosis is an infection spread by ticks and caused by Babesia parasites, which are tiny organisms (protozoa) that enter and destroy red blood cells. Many infected people do not develop symptoms. When symptoms do appear, they often resemble the flu and may include fever, chills, sweating, headache, body aches, and tiredness. Severe illness can cause … Read more