Twenty persons in the Quai To commune, Tuan Giao district of the Northwest province of Dien Bien were infected with Trichinella on September 2004. All these 20 patients were determined to have eaten raw lean pork ("lap" dish) from a local pick. Typical clinical symptoms were found in all the patients. Most patients were male (85%) and aged from 22 to 65 with most of 31-40 years old. The clinical symptoms appeared within 1-2 weeks in all patients and most of them had fever (100%), muscular pain (100%), difficult moving (100%), oedema (95%), dysphagia (90%), weight loss (90%), itching (85%), dyspnea (80%), diarrhea (50%), lisp (40%), abdominal pain (35%)
Trichinella ; epidemiology ; diagnosis

The immune correlate of host resistance induced by reinfection of Trichinella spiralis remains unclear. In this study, we investigated immune correlates between the resistance and serum IgG antibody level, CD23⁺ IgM⁺ B cells, and eosinophil responses induced by T. spiralis reinfection. Mice were primarily infected with 10 or 100 T. spiralis larvae (10 TS, 100 TS), respectively, and after 4 weeks, they were challenge infected with 100 T. spiralis larvae (10–100 TS, 100-100 TS). Upon challenge infections, 10–100 TS mice induced significantly higher levels of T. spiralis-specific total IgG antibody responses in sera and antibody secreting cell responses in spleens compared to 100-100 TS mice, resulting in significantly reduced worm burdens in 10–100 TS mice (60% and 70% reductions for adult and larvae, respectively). Higher levels of eosinophils were found in mice primarily infected with 10 TS compared to those of 100 TS at week 8 upon challenge. CD23+ IgM+ B cells were found to be increased significantly in mice primarily infected with 10 TS. These results indicate that primary infection of 10 larvae of T. spiralis, rather than 100 larvae, induces significant resistance against reinfection which closely correlated with T. spiralis-specific IgG, eosinophil, and CD23+ IgM+ B cell responses.
Adult ; Animals ; Antibody Formation ; B-Lymphocytes ; Eosinophils ; Humans ; Immunoglobulin G ; Larva ; Mice* ; Spleen ; Trichinella spiralis* ; Trichinella*

Trichinosis is a worldwide parasitic infection caused by ingesting an uncooked raw meat containing viable larvae of nematode Trichinella. Although most cases have been reported in Western countries, the incidence has decreased due to strict control of meat handlings and improved hygiene in these countries. In Korea, the first case of Trichinella spiralis was reported in a patient who ingested an uncooked badger. We have also experienced four cases of Trichinella spiralis infestation among family members who showed typical clinical manifestations and laboratory findings after ingesting raw wild swine meat, and herein report the finding.
Animals ; Eating* ; Humans ; Hygiene ; Incidence ; Korea ; Larva ; Meat* ; Mustelidae ; Swine* ; Trichinella ; Trichinella spiralis ; Trichinellosis*

Trichinosis is a worldwide parasitic infection caused by ingesting an uncooked raw meat containing viable larvae of nematode Trichinella. Although most cases have been reported in Western countries, the incidence has decreased due to strict control of meat handlings and improved hygiene in these countries. In Korea, the first case of Trichinella spiralis was reported in a patient who ingested an uncooked badger. We have also experienced four cases of Trichinella spiralis infestation among family members who showed typical clinical manifestations and laboratory findings after ingesting raw wild swine meat, and herein report the finding.
Animals ; Eating* ; Humans ; Hygiene ; Incidence ; Korea ; Larva ; Meat* ; Mustelidae ; Swine* ; Trichinella ; Trichinella spiralis ; Trichinellosis*

As most infections by the helminth parasite elicit the recruitment of CD4+CD25+Foxp3+ T (T(reg)) cells, many scientists have suggested that these cells could be used for the treatment of immune-mediated inflammation and associated diseases. In order to investigate the distribution and alteration of activated T(reg) cells, we compared the expression levels of T(reg) cell activation markers in the ileum and gastrocnemius tissues 1, 2, and 4 weeks after infection. The number of T(reg) cells was monitored using GFP-coded Foxp3 transgenic mice. In mice at 1 week after Trichinella spiralis infection, the number of activated T(reg) cells was higher than in the control group. In mice at 2 weeks after infection, there was a significant increase in the number of cells expressing Foxp3 and CTLA-4 when compared to the control group and mice at 1 week after infection. At 4 weeks after infection, T. spiralis was easily identifiable in nurse cells in mouse muscles. In the intestine, the expression of Gzmb and Klrg1 decreased over time and that of Capg remained unchanged for the first and second week, then decreased in the 4th week. However, in the muscles, the expression of most chemokine genes was increased due to T. spiralis infection, in particular the expression levels of Gzmb, OX40, and CTLA-4 increased until week 4. In addition, increased gene expression of all chemokine receptors in muscle, CXCR3, CCR4, CCR5, CCR9, and CCR10, was observed up until the 4th week. In conclusion, various chemokine receptors showed increased expressions combined with recruitment of T(reg) cells in the muscle tissue.
Animals ; Gene Expression ; Helminths ; Ileum ; Inflammation ; Intestines ; Mice* ; Mice, Transgenic ; Muscles ; Parasites ; Receptors, Chemokine ; T-Lymphocytes, Regulatory* ; Trichinella spiralis ; Trichinella*

Eosinophils are multifunctional leukocytes implicated in protection against helminth infections. Although eosinophils comprise between 1~5% of peripheral blood leukocytes, they primarily reside in the gastrointestinal tract under homeostatic conditions, and rapidly proliferate upon parasitic infection. Intestinal infection with Trichinella spiralis (T. spiralis) induces eosinophilia when the parasite enters the larval stages and larvae finally migrate to the skeletal muscle. Eosinophils are known to mediate parasite death through antibody-dependent cellular cytotoxicity. In this study, we aimed to address the functional significance of eosinophils in the intestinal phase of T. spiralis infection by analysis of immune responses in the Peyer's patch (PP) of infected BALB/c and eosinophil-ablated ΔdblGATA mice. Trafficking of eosinophils to the PP was significantly increased, with upregulation of interleukin-5 at 14 days post infection. Eosinophil deficiency led to a significant augmentation of serum immunoglobulin (Ig) M and IgG1 antibody levels. In accordance with this, IgG1+ B cells in the PP were substantially increased in ΔdblGATA mice compared to that in BALB/c mice. Transforming growth factor-β expression in the PP of infected ΔdblGATA mice was significantly decreased compared to that in BALB/c mice, whereas the number of T. spiralis larvae in the diaphragm was increased. Taken together, these findings indicate that eosinophils contribute to the regulation of Th2 immune responses, and protect the host from T. spiralis attempting to establish larvae in the skeletal muscle.
Animals ; B-Lymphocytes ; Diaphragm ; Eosinophilia ; Eosinophils* ; Gastrointestinal Tract ; Helminths ; Immunoglobulin G ; Immunoglobulins ; Interleukin-5 ; Larva ; Leukocytes ; Mice ; Muscle, Skeletal ; Parasites ; Trichinella spiralis* ; Trichinella* ; Up-Regulation

The immune response against Trichinella spiralis at the intestinal level depends on the CD4⁺ T cells, which can both suppress or promote the inflammatory response through the synthesis of diverse cytokines. During the intestinal phase, the immune response is mixed (Th1/Th2) with the initial predominance of the Th1 response and the subsequent domination of Th2 response, which favor the development of intestinal pathology. In this context, the glucocorticoids (GC) are the pharmacotherapy for the intestinal inflammatory response in trichinellosis. However, its therapeutic use is limited, since studies have shown that treatment with GC suppresses the host immune system, favoring T. spiralis infection. In the search for novel pharmacological strategies that inhibit the Th1 immune response (proinflammatory) and assist the host against T. spiralis infection, recent studies showed that resiniferatoxin (RTX) had anti-inflammatory activity, which decreased the serum levels of IL-12, INF-γ, IL-1β, TNF-α, NO, and PGE₂, as well the number of eosinophils in the blood, associated with decreased intestinal pathology and muscle parasite burden. These researches demonstrate that RTX is capable to inhibit the production of Th1 cytokines, contributing to the defense against T. spiralis infection, which places it as a new potential drug modulator of the immune response.
Cytokines ; Drug Therapy ; Eosinophils ; Glucocorticoids ; Immune System ; Inflammation* ; Interleukin-12 ; Parasites ; Pathology ; T-Lymphocytes ; Therapeutic Uses* ; Trichinella spiralis ; Trichinellosis*

Trichinosis is a parasitic zoonosis caused by the nematode Trichinella spiralis. Anthelmintics are used to eliminate intestinal adults as well as tissue-migrating and encysted larvae. This study aimed to investigate the effects of ivermectin and myrrh obtained from the aloe-gum resin of Commiphora molmol on experimental trichinosis. Ninety albino mice were orally infected with 300 T. spiralis larvae. Drugs were tested against adult worms at day 0 and day 5 and against encysted larvae on day 15 and day 35 post-infection (PI). Mature worms and encysted larvae were counted in addition to histopathological examination of muscle specimens. Serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), total protein, albumin, globulin, urea, and creatinine values were estimated. Significant reductions in mean worm numbers were detected in ivermectin treated mice at day 0 and day 5 PI achieving efficacies of 98.5% and 80.0%, while efficacies of myrrh in treated mice were 80.7% and 51.5%, respectively. At days 15 and 35 post-infection, ivermectin induced significant reduction in encysted larval counts achieving efficacies of 76.5% and 54.0%, respectively, while myrrh efficacies were 76.6% and 35.0%, respectively. AST, ALT, urea, and creatinine levels were reduced, while total proteins were increased in response to both treatments compared to their values in the infected non-treated mice. Ivermectin use for controlling T. spiralis could be continued. Myrrh was effective and could be a promising drug against the Egyptian strains of T. spiralis with results nearly comparable to ivermectin.
Animals ; Antiparasitic Agents/administration & dosage/*pharmacology ; Drug Therapy, Combination ; Ivermectin/administration & dosage/*pharmacology ; Mice ; Terpenes/administration & dosage/*pharmacology ; *Trichinella spiralis ; Trichinellosis/*drug therapy

We have studied the genetic differences among four isolates of Trichinella including a new strain of Trichinella spiralis (ISS 623) recently found from a human case who took a badger in Korea. Because they have a different host origin and came from geographically separated regions, we supposed the genetic pattern of the isolates might be different as had been previously reported. It was analysed by PCR-RFLP analysis of the rDNA repeat that can readily distinguish a species or strain from others. Isolated genomic DNA of each isolate of Trichinella larvae was amplified with ITS1 specific primers and digested with restriction endonucleases. The PCR product of ITS1 was confirmed using Southern blot analysis to be a 910 bp fragment. The restriction fragments of each isolate had variable patterns when it was digested with Rsa 1 only. According to the RFLP patterns, the estimated genetic divergence between each isolate was different. In conclusion, four isolates of Trichinella including a new strain of T. spiralis obtained from a Korean patient may have genetic differences in the ITS1 region and the Shanghai isolate was genetically more similar to the Japanese unknown isolate than others in the ITS1 region.
Animals ; *DNA, Helminth ; *DNA, Ribosomal ; Human ; Polymerase Chain Reaction ; Polymorphism, Restriction Fragment Length ; Repetitive Sequences, Nucleic Acid ; Trichinella spiralis/*genetics/isolation & purification

Members of the genus Trichinella are small nematodes that can infect a wide range of animal hosts. However, their infectivity varies depending on the parasite and host species combination. In this study, we examined the susceptibility of 4 species of laboratory rodents, i.e., mice, rats, hamsters, and gerbils to Trichinella papuae, an emerging non-encapsulated Trichinella species. Trichinella spiralis and Trichinella pseudospiralis were also included in this study for comparison. Fifteen animals of each rodent species were infected orally with 100 muscle larvae of each Trichinella species. Intestinal worm burden was determined at day 6 and 10 post-inoculation (PI). The numbers of muscle larvae were examined at day 45 PI. The reproductive capacity index (RCI) of the 3 Trichinella species in different rodent hosts was determined. By day 6 PI, 33.2-69.6% of the inoculated larvae of the 3 Trichinella species became adult worms in the small intestines of the host animals. However, in rats, more than 96% of adult worms of all 3 Trichinella species were expelled from the gut by day 10 PI. In gerbils, only 4.8-18.1% of adult worms were expelled by day 10 PI. In accordance with the intestinal worm burden and the persistence of adults, the RCI was the highest in gerbils with values of 241.5+/-41.0 for T. papuae, 432.6+/-48 for T. pseudospiralis, and 528.6+/-20.6 for T. spiralis. Hamsters ranked second and mice ranked third in susceptibility in terms of the RCI, Rats yielded the lowest parasite RCI for all 3 Trichinella species. Gerbils may be an alternative laboratory animal for isolation and maintenance of Trichinella spp.
Animals ; *Animals, Laboratory ; Cricetinae ; *Disease Susceptibility ; Gerbillinae ; Intestines/parasitology ; Male ; Mice ; Muscles/parasitology ; Parasite Load ; Rats ; Rodent Diseases/*parasitology/pathology ; Trichinella/*growth & development ; Trichinellosis/parasitology/pathology/*veterinary