Millers contribution, along with the research on plaque by G. V. Black and J. L. Williams, served as the foundation for the current explanation of the etiology of caries. Several of the specific strains of lactobacilli were identified in 1921 by Fernando E. Rodríguez Vargas. In 1924 in London, Killian Clarke described a spherical bacterium in chains isolated from carious lesions which he called Streptococcus mutans. Although Clarke proposed that this organism was the cause of caries, the discovery was not followed up. Later, in 1954 in the US, Frank Orland working with hamsters showed that caries was transmissible and caused by acid-producing Streptococcus thus ending the debate whether dental caries were resultant from bacteria. It was not until the late 1960s that it became generally accepted that the Streptococcus isolated from hamster caries was the same as S. mutans.Tooth decay has been present throughout human history, from early hominids millions of years ago, to modern humans. The prevalence of caries increased dramatically in the 19th century, as the Industrial Revolution made certain items, such as refined sugar and flour, readily available. The diet of the "newly industrialized English working class" then became centered on bread, jam, and sweetened tea, greatly increasing both sugar consumption and caries. Etymology and usage
Naturalized from Latin into English (a loanword), caries in its English form originated as a mass noun that means "rottenness", that is, "decay". The word is an uncountable noun. Cariesology or cariology is the study of dental caries.
A normal immune system will suppress the infection but the tissue cysts will persist in that animal or human for years or for life. In immunocompromised individuals, dormant cysts can be reactivated and cause lesions in the brain, heart, lungs, eyes, and other tissues. A fetus may be at risk if a pregnant woman without immunity becomes infected. Symptoms in cats include fever, weight loss, diarrhea, vomiting, uveitis, and central nervous system signs. Disease in dogs includes paralysis, tremors, and seizures. Dogs and cats are usually treated with clindamycin. Genus Neospora has one important species, N. caninum, which affects dogs in a manner similar to toxoplasmosis. Neosporosis is difficult to treat. Genus Hepatozoon contains one species that causes hepatozoonosis in dogs and cats, H. canis. Animals become infected by ingesting an infected brown dog tick (Rhipicephalus sanguineus). Symptoms include fever, weight loss, and pain in the spine and limbs.The most common medications used to treat coccidian infections are in the sulfonamide antibiotic family.Depending on the pathogen and the condition of the animal, untreated coccidiosis may clear of its own accord, or become severe and damaging, and sometimes cause death. == References ==