%0 Journal Article
%T Schistosoma-associated Salmonella resist antibiotics via specific fimbrial attachments to the flatworm
%A Alison E Barnhill
%A Ekaterina Novozhilova
%A Tim A Day
%A Steve A Carlson
%J Parasites & Vectors
%D 2011
%I BioMed Central
%R 10.1186/1756-3305-4-123
%X Using a novel antibiotic protection assay, our results reveal that Schistosoma-associated Salmonella are refractory to eight different antibiotics commonly used to treat salmonellosis. The efficacy of these antibiotics was decreased by a factor of 4 to 16 due to this association. Salmonella binding to schistosomes occurs via a specific fimbrial protein (FimH) present on the surface on the bacterium. This same fimbrial protein confers the ability of Salmonella to bind to mammalian cells.Salmonella can evade certain antibiotics by binding to Schistosoma. As a result, effective bactericidal concentrations of antibiotics are unfortunately above the achievable therapeutic levels of the drugs in co-infected individuals. Salmonella-Schistosoma binding is analogous to the adherence of Salmonella to cells lining the mammalian intestine. Perturbing this binding is the key to eliminating Salmonella that complicate schistosomiasis.Schistosomes are parasitic helminths that infect humans, with life cycles involving snails as intermediate hosts. Schistosomiasis occurs in 74 developing tropical and subtropical countries in which over 200 million people are infected. Of those, 120 million patients show symptoms with 20 million severely infected. There are 14,000 deaths per year due to schistosomiasis [1].Salmonella spp. is a common water- and food-borne cause of gastrointestinal and systemic diseases worldwide. Approximately 2 million individuals die each year from diarrheal disease and Salmonella is a leading cause of this malady. In the U.S. alone, Salmonella causes about 1.4 million infections per year [2].Concurrent Schistosoma-Salmonella infections occur when enteroinvasive Salmonella enter the systemic circulation and attach to the tegument of adult Schistosoma [3,4] present in the mesenteric vasculature. This interaction apparently provides a refuge in which the bacterium can evade systemic antibiotic therapy. For example, chloramphenicol-sensitive S. typhi were demonstrated
%U http://www.parasitesandvectors.com/content/4/1/123