Age-related detection and molecular characterization of Cryptosporidium suis and Cryptosporidium scrofarum in pre- and post-weaned piglets and adult pigs in Japan.

We investigated the distribution of Cryptosporidium in pigs in Japan by immunofluorescence staining of fecal samples and characterization of isolates by multilocus sequencing. The 344 animals sampled on eight farms included pre-weaned piglets (<1 month old; n = 55), weaned piglets (1-2 months old; n = 65), finished pigs (2-4 months old, n = 105) and of 4-6 months old (n = 67), sows (n = 36), and boars (n = 16). Average prevalence of Cryptosporidium on farms was 32.6%, ranging from 4.9 to 58.1%, decreasing with animal age (prevalences of <1 month old, 1-2 months old, 2-4 months old, 4-6 months old, sows, and boars were 27.3, 47.7, 41.9, 22.4, 11.1, 18.8%, respectively). Piglets (<1 and 1-2 months old) showing signs of diarrhea shed relatively more oocysts (5.28 in average log scale of oocysts per gram) in feces than piglets with normal or loose stools (those of 4.90). Thirty seven successful sequencing of the 18S ribosomal RNA gene among 62 examined samples revealed that all of the identified isolates were Cryptosporidium suis or Cryptosporidium scrofarum, which are generally specific to pigs, and that other species, such as zoonotic Cryptosporidium parvum, were absent. Interestingly, C. suis was frequently found in piglets younger than 2 months old, while C. scrofarum infection was more prevalent in older pigs which also showed increased prevalence of mixed C. suis and C. scrofarum infections. Sequencing of actin gene loci revealed the existence of variants of both Cryptosporidium species in pigs in Japan. Although the number of pigs examined in this study was relatively low, our results suggest that Cryptosporidium infection is widespread among pigs in Japan. In addition, the possibility of age-related specificity and pathogenicity in pig infections is also suggested.

Molecular phylogenetic analysis of Orientia tsutsugamushi based on the groES and groEL genes.

DNA sequences encoding the GroES and GroEL proteins of Orientia tsutsugamushi were amplified by the PCR and sequenced. Pairwise alignment of full-length groES and groEL gene sequences indicated high sequence similarity (90.4-100% and 90.3-100%) in O. tsutsugamushi, suggesting that these genes are good candidates for the molecular diagnosis and phylogenetic analysis of scrub typhus. Comparisons of the 56-kD type-specific antigen (TSA) protein gene and the groES and groEL genes showed that genotypes based on the 56-kD TSA gene were not related to a cluster containing the groES and groEL genes in a dendrogram, suggesting that a gene rearrangement may be associated with homologous recombination in mites.

[Prevalence of intestinal canine and feline parasites in Saitama Prefecture, Japan].

We studied the prevalence of intestinal parasites in animal companions in Saitama Prefecture, Japan, where no detailed data is currently available. Between May 1999 and December 2007, fecal samples were collected from 906 dogs and 1,079 cats in public animal shelters and examined by microscopy. Overall, prevalence of intestinal parasites in dogs was 38.6% and cats 43.1%. Trichuris vulpis was the most prevalent canine parasite species (22.3%), followed by Toxocara canis (12.5%), Ancylostoma caninum (10.4%), Isospora ohioensis (2.1%), Spirometra erinaceieuropaei (1.0%), Crypstosporidium sp. (0.9%), Giardia intestinalis (0.9%), I. canis (0.6%), Taeniidae (0.3%), Dipylidium caninum (0.2%), Echinostoma sp. (0.1%), and Pentatrichomonas hominis (0.1%). T. cati was the most prevalent feline parasite species (21.8%), followed by A. tubaeforme (13.2%), S. erinaceieuropaei (8.3%), I. felis (4.5%), Cryptosporidium sp. (2.8%), I. rivolta (2.2%), Pharyngostomum cordatum (1.6%), D. caninum (1.4%), Eimeria sp. (0.3%), Taeniidae (0.2%), Trichuris sp. (0.2%), Capillaria sp. (0.1%), Diphyllobothrium nihonkaiense (0.1%), and Metagonimus yokogawai (0.1%). Further molecular analysis to identify canine Taeniidae species and canine and feline Cryptosporidium species identified one canine taeniid positive species as Echinococcus multilocularis. Cryptosporidium species were identified as C. canis and C. felis. Parasites E. multilocularis and Cryptosporidium spp. in animal hosts were the first to be recorded in this prefecture. Compared to previous surveys conducted in the same area, the endemicity of some parasites appeared to have decreased, but some others remain. Given that most of these parasites have zoonotic potential, indicates the importance of having current data on parasite dissemination among animal companions. Government public health agencies should be responsible for educating pet owners about the control and prevention of zoonotic risk from such parasites.

Cyclospora infection in an immunocompetent patient in Japan.

Cyclospora cayetanensis is a coccidian protozoa that was newly recognized in 1979 in Papua New Guinea. We report the case of a 42-year-old French man who had visited Vietnam and presented with fever and watery diarrhea that had lasted for more than 2 weeks. The patient was diagnosed with C. cayetanensis infection by examination of a stool smear using UV fluorescence microscopy. Based on this rare case, we recommend that Cyclospora infection might be considered in the differential diagnosis of traveler's diarrhea in immunocompetent patients.

[An outbreak of cryptosporidiosis associated with swimming pools].

A waterborne outbreak of cryptosporidiosis occurred among visitors at a hotel with a swimming pool, gymnasium, and other sports facilities, in northern Nagano Prefecture. The outbreak began in late August, peaked on August 27 and 28, and tapered off at the beginning of September 2004. On August 30, 288 clinical cases with digestive symptoms, including watery diarrhea, vomiting, abdominal cramps and tenesmus, were reported to local authorities. Among case-patients who submitted stool samples, 74 were positive for Cryptosporidium. Descriptive epidemiology, environmental investigations, and laboratory tests suggested that a fecal accident in the swimming pool by swimmers infected before attending the summer training camp was thought to be the source of contamination, and case-patients were mostly among swimmers. Some other clinical-cases had no history of swimming in the pool during their stay and likely were infected through drinking contaminated self-made sports drinks dissolved in water from contaminated faucets and/or sinks nearby the gymnasium toilet. The sink was used to deal with the aftermath of a toilet accident at the entrance of the toilet by a swimming school attendee on August 21. This report is, to our knowledge, the first of a cryptosporidiosis outbreak associated with swimming pools in Japan.

Scrub typhus in Japan: epidemiology and clinical features of cases reported in 1998.

Surveillance for scrub typhus was conducted in Japan in 1998 using a questionnaire. A total of 462 cases were reported. Scrub typhus occurred in both the fall and spring in the northern part of Honshu (the main island), and in the fall in the central part of Honshu and on the island of Kyushu. The occurrence of the disease varied with age, gender, and activity. Seventy-six percent of the patients were more than 51 years old, and 36% and 16% of the patients were engaged in farm work and forestry, respectively. Fever, rash, and eschar were detected in 98%, 93%, and 97% of the patients, respectively. Elevated levels of C-reactive protein, aspartate transaminase, and alanine transaminase were detected in 96%, 87%, and 77% of the patients, respectively. Disseminated intravascular coagulation developed in 34 cases and had a unique regional distribution. This study shows the status of scrub typhus in Japan in 1998 and provides important information for diagnosis and prevention.