A Rare Human Helminth Infection in Russia.

Currently, more than 500,000 cases of various helminthes in humans are reported annually in the Russian Federation. This figure may not reflect the true incidence of helminthes, as only nine separate nosological forms are compulsory notifiable. The rest of the species of detected helminthes are included in a separate category of "other helminthes" or "rare helminthes". The bulk of the latter is represented by the helminthes with a rate of incidence that does not exceed one case per 100,000 people. This review is based on data derived from publications in the Russian language, both from the Russian Federation and international, as well as data available from various health treatment facilities in Russia. These data largely cover the period of the 1990s-2010s. A total of 15 species of "rare helminthes" are described in this review: anisakiosis, capillariosis, clonorchosis, dioctophymosis, dipylidiosis, echinochasmosis, fasciolosis, gastrodiscoidosis (amphistomiosis), metagonimosis, metorchiosis, nanophyetosis, pseudamphistomosis, sparganosis (spirometrosis), strongyloidosis and trichostrongylosis. Details of their geographical distribution, clinical and epidemiological peculiarities, and the difficulties they pose in diagnosis are provided. The public health importance of "rare helminthes" in Russia at present and in the forthcoming years is stressed.