Usefulness of a single-assay chemiluminescence test (Tularaemia VIRCLIA IgG + IgM monotest) for the diagnosis of human tularemia. Comparison of five serological tests

Tularemia is a zoonosis endemic in certain areas of the northern hemisphere. It is caused by Francisella tularensis, facultative intracellular gram negative coccobacillus. Four subspecies have been described (F. tularensis subsp. tularensis, F. tularensis subsp. holarctica, F. tularensis subsp. mediasiatica, and F. tularensis subsp. novicida), but only F. tularensis subsp. tularensis and F. tularensis subsp. holarctica are of epidemiological importance as agents causing human disease. F. tularensis subsp. tularensis is principally found in North America and, to a lesser extent, in Europe. In contrast, F. tularensis subsp. holarctica is basically distributed throughout Europe and Asia and less often found in North America [1]. Although human tularemia normally presents as sporadic cases, important epidemic outbreaks have recently occurred in various countries. In Finland, outbreaks of human tularemia have appeared every 3 or 4 years, with a maximum incidence of around 18/100,000 inhabitants in 2000 [2]. Similar outbreaks appeared in Sweden in 2000, 2003, and 2012 [3], in France in 2008 [4], and in Turkey [5]. Spain has seen two important outbreaks produced by F. tularensis subs. Holarctica over the last few years. The first was in 1997– 1998, with 604 cases [6, 7], and the second, in 2007–2008, with 507 confirmed cases [8].