Unapparent Microsporidial Infection among Immunocompetent Humans in the Czech Republic

Abstract

In the present population-based study, we determined the prevalences of the most common humanpathogenic microsporidia, Encephalitozoon spp. and Enterocytozoon bieneusi, in asymptomatic healthy people living in the Czech Republic. A total of 382 males and females (ages, 1 to 84 years) living in the Czech Republic, of whom 265 were Czech nationals and 117 were foreign students, were included in a study testing for the presence of microsporidia by use of coprology and molecular methods. Single-species infections with Enterocytozoon bieneusi or an Encephalitozoon sp. were detected for 9 and 136 individuals, respectively. Moreover, coinfections were detected for 14 individuals. Four genotypes of 3 human-pathogenic Encephalitozoon spp. and 7 E. bieneusi genotypes, including 3 novel genotypes, were detected. Some of these were reported in humans for the first time. The highest prevalence was recorded for individuals older than 50 years and for loose, unformed stool samples. These findings clearly show that exposure to microsporidia is common among immunocompetent people and that microsporidiosis is not linked to any clinical manifestation in healthy populations.

A New and Highly Divergent Enterocytozoon bieneusi Genotype Isolated from a Renal Transplant Recipient

“…However, recent studies have provided clear evidence that these infections are not restricted to AIDS and are also common in immunocompromised non-HIV-infected individuals, such as solid-organ transplant recipients (5,7,8). Moreover, Sak et al have recently provided new insights into the understanding of microsporidiosis, highlighting a high prevalence of microsporidia in healthy subjects (11,12). These findings suggest that the real distribution of microsporidiosis in humans is probably underestimated (1).…”

Phylum Microsporidia: Dangerous Waterborne Pathogens, A Review

“…In these countries is prevalence in HIV negative 5.4 -58 % (Bretagne et al, 1993). In Czech Republic Sak et al (2011) detected prevalence of infection caused by this pathogen around 2 % in immunocompetent humans. In Slovakia prevalence of E. bieneusi in children living in Roma settlements was 4.2 % (Halánová et al, 2013).…”

Encephalitozoon cuniculi Genotype I as a Causative Agent of Brain Abscess in an Immunocompetent Patient

“…The abscess aspirate and stool and urine samples were used for standard molecular identification of the microsporidial species and genotype (5,8). This revealed the pres-ence of Encephalitozoon cuniculi genotype I in the abscess aspirate, as well as in stool and urine specimens, before treatment (Fig.…”

“…Although unapparent human infections seem to be frequent (8), the documented cases of clinical infections have been recorded in patients with severe immunodeficiency caused mostly by AIDS (6,10,11) or other damage to the immune system (7). Successful resolutions of such cases have been scarce (1).…”

“…In human cases of symptomatic infections, E. cuniculi genotype III ("dog" strain) seems to be the most frequent (3, 9, 10); however, genotype I ("rabbit" or "rodent" strain) has been recorded as well (2). This genotype has also been detected in healthy humans (8).…”