Cysticercosis is a tissue infection caused by the young form of the pork tapeworm. People may have few or no symptoms for years. In some cases, particularly in Asia, solid lumps of between one and two centimetres may develop under the skin. After months or years these lumps can become painful and swollen and then resolve. A specific form called neurocysticercosis, which affects the brain, can cause neurological symptoms. In developing countries this is one of the most common causes of seizures.Cysticercosis is usually acquired by eating food or drinking water contaminated by tapeworms eggs from human feces. Among foods egg-contaminated vegetables are a major source. The tapeworm eggs are present in the feces of a person infected with the adult worms, a condition known as taeniasis. Taeniasis, in the strict sense, is a different disease and is due to eating cysts in poorly cooked pork. People who live with someone with the pork tapeworm have a greater risk of getting cysticercosis. The diagnosis can be made by aspiration of a cyst. Taking pictures of the brain with computer tomography (CT) or magnetic resonance imaging (MRI) are most useful for the diagnosis of disease in the brain. An increased number of a type of white blood cell, called eosinophils, in the cerebral spinal fluid and blood is also an indicator.Infection can be effectively prevented by personal hygiene and sanitation: this includes cooking pork well, proper toilets and sanitary practices, and improved access to clean water. Treating those with taeniasis is important to prevent spread.
Estimates from 2010 were that it contributed to at least 50,000 deaths annually.In US during 1990–2002, 221 cysticercosis deaths were identified. Mortality rates were highest for Latinos and men. The mean age at death was 40.5 years (range 2–88). Most patients, 84.6%, were foreign born, and 62% had emigrated from Mexico. The 33 US-born persons who died of cysticercosis represented 15% of all cysticercosis-related deaths. The cysticercosis mortality rate was highest in California, which accounted for 60% of all cysticercosis deaths. History
The earliest reference to tapeworms were found in the works of ancient Egyptians that date back to almost 2000 BC. The description of measled pork in the History of Animals written by Aristotle (384–322 BC) showed that the infection of pork with tapeworm was known to ancient Greeks at that time. It was also known to Jewish and later to early Muslim physicians and has been proposed as one of the reasons for pork being forbidden by Jewish and Islamic dietary laws. Recent examination of evolutionary histories of hosts and parasites and DNA evidence show that over 10,000 years ago, ancestors of modern humans in Africa became exposed to tapeworm when they scavenged for food or preyed on antelopes and bovids, and later passed the infection on to domestic animals such as pigs.Cysticercosis was described by Johannes Udalric Rumler in 1555; however, the connection between tapeworms and cysticercosis had not been recognized at that time.