Columbia Encyclopedia

Search results

287 results found

tick

(Encyclopedia)tick, small, parasitic arachnid of the order Ixodida, closely related to the mites. Ticks, which are larger than the often microscopic mites, are all parasitic in at least one developmental stage; mos...

streptococcus

(Encyclopedia)streptococcus strĕpˌtəkŏkˈəs [key], any of a group of gram-positive bacteria, genus Streptococcus, some of which cause disease. Streptococci are spherical and divide by fission, but they remain ...

food poisoning

(Encyclopedia)food poisoning, acute illness following the eating of foods contaminated by bacteria, bacterial toxins, natural poisons, or harmful chemical substances. It was once customary to classify all such illn...

MERS

(Encyclopedia)MERS or Middle East respiratory syndrome, relatively rare viral disease caused by MERS-CoV, a coronavirus. Although some infected persons have no or only coldlike symptoms, in most known cases of MERS...

foot-and-mouth disease

(Encyclopedia)foot-and-mouth disease or hoof-and-mouth disease, highly contagious disease almost exclusive to cattle, sheep, swine, goats, and other cloven-hoofed animals. It is caused by a virus, specifically an a...

chlamydia

(Encyclopedia)chlamydia kləmĭdˈēə [key], genus of microorganisms that cause a variety of diseases in humans and other animals. Psittacosis, or parrot fever, caused by the species Chlamydia psittaci, is transmi...

coccidioidomycosis

(Encyclopedia)coccidioidomycosis kŏksĭdˌēoiˌdōmīkōˈsĭs [key], systemic fungus disease (see fungal infection) endemic to arid regions of the Americas, contracted by inhaling dust containing spores of the f...

rotavirus

(Encyclopedia)rotavirus, double-stranded RNA virus, genus Rotavirus, with a wheellike appearance that can cause severe watery diarrhea and vomiting, sometimes leading to severe dehydration and death. The virus is t...

toxin

(Encyclopedia)toxin, poison produced by living organisms. Toxins are classified as either exotoxins or endotoxins. Exotoxins are a diverse group of soluble proteins released into the surrounding tissue by living ba...

trichinosis

(Encyclopedia)trichinosis trĭkˌĭnīˈəsĭs [key], parasitic disease caused by the roundworm Trichinella spiralis. It follows the eating of raw or inadequately cooked meat, especially pork. The larvae are releas...