Task 2: Tracing the Origins of Salmonella Outbreaks

Salmonella enteriditis is a human pathogen found in chicken carcasses, eggs, and egg products, and a increase in the amount of infected patients in U.S. and England has been observed since the 1980’s. A possible explanation of these events could be found by studying the incidence of other Salmonella serotypes such as S. typhimurium and S. pullorum.

Through epidemiological surveys a new hypothesis has been analyzed: salmonellosis in human could be explained by the filling from S. enteriditis serotype of the empty ecological niche left by the other two serotypes. S. gallinarum and S. pullorum are responsible of avian salmonellosis and after their eradication in the 1960’s S. enteriditis became established in poultry flocks.

Studies reveal that S. enteriditis shares the same antigen with. S. gallinarum and S. pullorum (O antigen), which means that as the eradication of these last two serotypes was taking place, the possibility of immunity against S. enteriditis was being lost.

As a result human salmonellosis cases have increased at an almost constant rate since the 1960s and an effective action against this might be to reestablish flock immunity through vaccination.

Summary of :

Enhanced: Tracing the Origins of Salmonella Outbreaks (Science Magazine)

link to this article: HERE