A new serovar of multidrug-resistant Salmonella enterica bacteria that has been associated with a high proportion of severe infections is emerging across Europe. Now researchers have characterised the strain and warn that the bacterium may be even more prevalent than had been thought.
The serovar, known as monophasic Typhimurium-like S. enterica, is genetically diverse and difficult to identify definitively, and so may be under-reported by existing surveillance programmes, say the researchers this week in Eurosurveillance.
One strain of Salmonella Typhimurium, known as DT104, emerged in the 1990s and caused a severe global epidemic that peaked in 1996 in the UK, when 4000 cases where identified. The new serovar (a group of related isolates characterised by their cell surface antigens) was rarely detected before the mid-1990s, but now appears to be rapidly spreading throughout Europe, and researchers fear that it could cause a similar epidemic to the DT104 strain. Human infections with the new strain have mostly resulted from contact with pigs and pork products, but have also been linked to poultry and cattle.
"In order to prevent a global epidemic of these newly emerging clones or strains, as occurred with Typhimurium DT104, appropriate intervention strategies need to be put in place as soon as possible, particularly in pig husbandry throughout the EU," write the researchers, Katie Hopkins and colleagues, from public health agencies