Coccidiosis

Coccidiosis is a parasitic disease of the intestinal tract caused by microscopic organisms called coccidians. The disease spreads from one dog to another by contact with infected feces. It is most severe in young or weak animals and causes a profuse, watery diarrhea which may be bloody.

Coccidia are small protozoans, one-celled organisms that multiply in the intestinal tract. The primary sign of coccidiosis is diarrhea. The diarrhea may be mild to severe depending on the level of infection. Severely affected animals may lose their appetite, become dehydrated and in some instances die from the disease. The response to treatment is usually not dramatic as drugs do not kill the organism, but rather inhibit their ability to reproduce. Therefore, elimination of the coccidia from the intestine is very gradual. By inhibiting the ability of the coccidia to reproduce, it gives the body time to build an immune response and removes the remaining organisms from the gut. The primary drugs used to treat coccidiosis are sulfonamides (such as sulfadimethoxine) and amprolium.

Puppies with diarrhea should be thoroughly evaluated for other intestinal diseases and parasites. Just because a coccidial oocyst is seen in the stool of a puppy with diarrhea, it does not mean that it is the primary cause of the infection.