Emerging Trichinella britovi infections in free ranging pigs of Greece.

Trichinella infections in humans and pigs have been documented in Greece since 1945 and a high prevalence of infection in pigs occurred in the 1950s. Up to 1984 only sporadic infections in humans were documented, and this zoonosis was not considered as a public health problem until 2009 when a human outbreak caused by the consumption of pork from an organic pig farm occurred. In the present study, we describe the re-emergence of Trichinella spp. infections in free-ranging pigs from organic farms of 3 counties (Dramas, Evros and Kavala) in Northern-Eastern Greece during the period 2009-2012. Totally 37 out of 12,717 (0.29%) free-ranging pigs which were tested during the period in question, were positive for Trichinella spp. larvae. The etiological agent was identified as Trichinella britovi. The average larval burden was 13.7 in the masseter, 6.2 in the foreleg muscles and 7.5 in the diaphragm. The 37 positive animals originated from seven free range pig farms. The practice of organic pig production systems in Greece has grown in popularity over the last years due to the increasing interest of consumers for products considered as traditional. However, this type of pig production increases the risk for Trichinella spp. infections, since animals can acquire the infection by feeding on carcasses or the offal of hunted or dead wild animals. The awareness and education of hunters and farmers is extremely important to reduce the transmission among free ranging pigs and the risk for humans.