Salmonella infections
The term salmonellosis is a used for several Salmonella infections of humans and animals caused by Salmonella Enterica and S. Bongori. Salmonella Enterica is divided into 6 subspecies, viz. enterica, salamae, arizonae, diarizonae, houtenae and indica. (Names are retained only for subspecies enterica serovars. These names must no longer be italicised. The first letter is a capital letter. In clinical practice the subspecies name need not be indicated as only serovars of subspecies enterica bear a name, e.g. Typhimurium is serovars of subspecies enterica. The name Salmonella Typhimurium may be used for routine practice). The most common 'serovars' (strains with serological variation) that cause infections in humans and food animals belong to Salmonella Enterica subspecies enterica. Over 2,500 serovars are known. Some of these affect only certain species of animals while others occur in a wide range of species. Salmonella is capable of prolonged survival outside the intestine. There is concern over the increasing resistance of some serovars to antimicrobials. Most human salmonellosis infections are S. Enteritidis (which originates from infected poultry and eggs) and S. Typhimurium (occurs in a variety of animals, including turkeys). Other salmonellae are S. Thompson, S. Menston, S. Virchow and S. Haddar. The S. Pullorum and S. Gallinarum strains are non-motile and highly host specific for poultry, whereas rest all salmonellae are motile and of zoonotic importance. The bacteria are fairly resistant to normal climate, surviving months in litter but are susceptible to normal disinfectants. Salmonellae are inactivated by direct exposure to sunlight, heat treatment, phenol, formalin, dichloride of mercury or potassium permanganate. Phenolic compounds are the most effective disinfectants under field conditions.