Prevalence and diversity of Encephalitozoon spp. and Enterocytozoon bieneusi in wild boars (Sus scrofa) in Central Europe

Abstract

From 2011 to 2012, the occurrence of Enterocytozoon bieneusi and Encephalitozoon spp. was surveyed at 29 randomly selected localities (both forest areas and enclosures) across four Central European countries: Austria, the Czech Republic, Poland, and the Slovak Republic. Isolates were genotyped by PCR amplification and characterization of the internal transcribed spacer (ITS) region using Enterocytozoon and Encephalitozoon-specific protocols. PCR revealed 16 mono-infections of Encephalitozoon cuniculi, 33 mono-infections of Enterocytozoon bieneusi and 5 concurrent infections of both Encephalitozoon cuniculi and Enterocytozoon bieneusi out of 460 faecal samples. Two genotypes (I and II) were revealed by sequence analysis of the ITS region of Encephalitozoon cuniculi. Eleven genotypes, five previously found in other hosts including domestic pigs (D, EbpA, EbpC, G and Henan-I) and six novel (WildBoar1-6), were identified in Enterocytozoon bieneusi. No other microsporidia infection was found in the examined faecal samples. Prevalence of microsporidia at the locality level ranged from 0 to 58.8 %; the prevalence was less than 25 % at more than 86 % of localities. Enterocytozoon bieneusi was detected as a predominant species infecting Eurasian wild boars (Sus scrofa). The present report is the most comprehensive survey of microsporidia infections in wild boars within the Czech Republic and selected Central European countries.

Zoonotic and Potentially Host-Adapted Enterocytozoon bieneusi Genotypes in Sheep and Cattle in Northeast China and an Increasing Concern about the Zoonotic Importance of Previously Considered Ruminant-Adapted Genotypes

“…The close genetic relationship of genotypes G and NECA1 to NECA5 with many human-pathogenic genotypes in group 1 is also of potential zoonotic concern. In addition to cattle, genotype G also existed in pigs from China and Germany, horses and wild boar from the Czech Republic, and a drinking water source in China, and genotype CS-4 was found in pigs from China (4,14,38,49,50). We concluded that cattleharbored E. bieneusi genotypes have zoonotic potential and are implicated in public health.…”

High Prevalence of Enterocytozoon bieneusi in Asymptomatic Pigs and Assessment of Zoonotic Risk at the Genotype Level

“…The percentages of zoonotic genotypes were observed to vary in different countries or different areas within a country, ranging from 33.3% to 100% (Table 1). We also noticed that all the E. bieneusi isolates were identified as zoonotic in two studies conducted in Austria and the Czech Republic (17,30). However, the risk that pigs pose to humans might be greater in the Czech Republic than in Austria, as a higher occurrence of E. …”

“…The internal transcribed spacer (ITS) region of the rRNA gene is most commonly used in genotyping E. bieneusi isolates. To date, besides humans, it has been isolated from pigs, wild boars, macaques, dogs, cats, cattle, llamas, horses, gorillas, baboons, raccoons, muskrats, beavers, foxes, otters, chickens, pigeons, parrots, sparrows, aquatic birds, and falcons (15)(16)(17)(18)(19). The finding of the same ITS genotypes of E. bieneusi in humans and animals supported the possibility of zoonotic transmission.…”

“…June 2014 Volume 80 Number 12 aem.asm.org 3703 bieneusi in pigs was seen in the Czech Republic than in Austria (17,30). Thus, in the assessment of the zoonotic risk of E. bieneusi genotypes of animal origin in a specific farm or area, it is scientific and reasonable to consider the occurrence of the parasite together with the percentage of zoonotic genotypes.…”

“…Pigs are considered to be one of the most important reservoir hosts of E. bieneusi, and molecular epidemiological surveys have been conducted in 11 countries since the first report of E. bieneusi in pigs in Switzerland (20). Genotyping data for E. bieneusi isolates from pigs, including wild boars, have identified 34 genotypes, with 13 of them found in humans (Table 1) (17,(21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31). Therefore, genotyping of E. bieneusi isolates from pigs will provide useful information to assess the risk of zoonotic transmission.…”