ABSTRACT
Thelazia callipaeda, T. californiensis and T. gulosa are three causative agents of human thelaziasis. Most of the reported cases were caused by T. callipaeda, occurring in the old world, particularly in Asian and European countries. T. californiensis and T. gulosa have rarely been reported infecting humans in North America. T. callipaeda has long been called the oriental eye worm, referring to its traditional distribution across eastern and southeastern Asia (i.e., China, Korea, Japan, Indonesia, Thailand, and India) where infection is endemic in animals and humans, usually in poorer rural areas and mainly among children and the elderly. The identification of the parasite was mainly based on the characteristics of oral and genital organs. In Asia and Europe, vectors for this nematode are male Phortica okadai and P. variegata drosophilids respectively, which feed on ocular secretions of hosts and transmit infective stage larvae to domestic and wild carnivores, lagomorphs, and humans. China probably has the largest number of cases with thelaziasis in the world, and lots of cases have been existed in other Asian countries such as Japan and Korea. Although a few of human cases have been reported, there were high infection rates of wild animals and domesticated dogs and cats in most of European countries. Based on the cox1 gene, a total of 21 haplotypes were identified in the samples from worldwide, in which, one circulated only in European countries (h1), while the other 20 haplotypes were distributed in Korea, Japan and China. In general, the Chinese clinical isolates of T. callipaeda expressed high genetic diversity. The population differences between Europe and Asian countries were greater than those among China, Korea and Japan. The T. callipaeda populations from Europe and Asia should be divided into two separate sub-populations. These two groups started to diverge during the middle Pleistocene.
ABSTRACT
We described a human case of zoonotic dog tapeworm, Dipylidium caninum (Eucestoda: Dilepidiidae), rarely occurring in China. The mother of a 17 month-old boy noted the appearance of small white and active worms over a month period in her son’s feces, but the boy was asymptomatic except mild diarrhea. We observed 3 tapeworm proglottids resembling cucumber seeds in his stool sample. Microscopically, each proglottid had 2 genital pores, 1 on each lateral edge, and numerous egg capsules in the uterus. The patient was successfully treated with a single oral dose of praziquantel. Adult worms were recovered in the diarrheic stool after praziquantel treatment and purgation. His family had household pet dogs for several years, and he might have acquired the infection by ingestion of infected fleas of his pet dogs. A history of dog or cat pets and flea bites may be important clues to diagnosis of D. caninum infection. The infected pets should also be treated.
Subject(s)
Adult , Animals , Cats , Dogs , Humans , Male , Capsules , Cestoda , Cestode Infections , China , Diagnosis , Diarrhea , Eating , Family Characteristics , Feces , Mothers , Ovum , Praziquantel , Siphonaptera , UterusABSTRACT
Trichinella spiralis nudix hydrolase (TsNd) gene encoding a 46 kDa protein was expressed in Escherichia coli and the potential of recombinant TsNd protein (rTsNd) as an antigen for the serodiagnosis of trichinellosis was investigated by ELISA and compared with those of ELISA with T. spiralis muscle larval excretory–secretory (ES) antigens. The sensitivity of both ELISA was 100% (30/30), for the detection of anti-Trichinella IgG antibodies in sera of the experimentally infected mice, and the specificity of rTsNd-ELISA and ES-ELISA was 100% (54/54) and 98% (53/54), respectively (P>0.05). Serum anti-Trichinella antibodies were firstly detected by rTsNd-ELISA at 14 days post infection (dpi), then continued to increase with a detection rate of 100% at 36 dpi. The anti-Trichinella antibody levels at different times after infection were statistically different (P<0.05). The results showed that the rTsNd might be a potential candidate antigen for specific serodiagnosis of trichinellosis. But, it needs to be further evaluated with sera of the patients with trichinellosis and other helminthiasis.
ABSTRACT
The phylogenetic location of Chinese Spirometra sparganum isolates remains unclear. The aim of this study was to explore the phylogenetic location of the Spirometra sparganum isolates from China. The 28S ribosomal DNA [rDNA] D1 sequences of 14 Spirometra sparganum isolates collected from thirteen locations in China were analyzed by using Neighbor-Joining [NJ], maximum parsimony [MP] and Bayesian inference [BI], respectively. To investigate the deep variance of 28S rDNA D1 region among included species, the secondary structure of 28S rDNA D1 region was also calculated using the program RNA structure. The genus Spirometra as a monophyletic group was evidenced by two inference methods [MP and BI]. All sequences within the genus Spirometra had a bulge of a cytosine residue [Bulge C] in the stem 13 of the secondary structure model of 28S rRNA D1 region. Varietal sites in sequences from all thirteen Chinese isolates were appeared in loops. In loops, adenine was the most abundant base [averagely 41.9%] followed by guanine [averagely 30.0%], and cytosine [averagely 15.1%]. In stems, the average percentage of G + C [58.3%] was higher than the percentage of A + T [41.7%]. The 'Bulge C' in the stem 13 of the 28S rDNA D1 secondary structure could be as a suitable mark to identify the Spirometra species
ABSTRACT
The present study reports a human case of cutaneous gnathostomiasis with recurrent migratory nodule and persistent eosinophilia in China. A 52-year-old woman from Henan Province, central China, presented with recurrent migratory reddish swelling and subcutaneous nodule in the left upper arm and on the back for 3 months. Blood examination showed eosinophila (21.2%), and anti-sparganum antibodies were positive. Skin biopsy of the lesion and histopathological examinations revealed dermal infiltrates of eosinophils but did not show any parasites. Thus, the patient was first diagnosed as sparganosis; however, new migratory swellings occurred after treatment with praziquantel for 3 days. On further inquiring, she recalled having eaten undercooked eels and specific antibodies to the larvae of Gnathostoma spinigerum were detected. The patient was definitely diagnosed as cutaneous gnathostomiasis caused by Gnathostoma sp. and treated with albendazole (1,000 mg/day) for 15 days, and the subsequent papule and blister developed after the treatment. After 1 month, laboratory findings indicated a reduced eosinophil count (3.3%). At her final follow-up 18 months later, the patient had no further symptoms and anti-Gnathostoma antibodies became negative. Conclusively, the present study is the first report on a human case of cutaneous gnathostomiasis in Henan Province, China, based on the past history (eating undercooked eels), clinical manifestations (migratory subcutaneous nodule and persistent eosinophilia), and a serological finding (positive for specific anti-Gnathostoma antibodies).
Subject(s)
Animals , Female , Humans , Middle Aged , Anthelmintics/therapeutic use , Antibodies, Helminth/immunology , China , Eosinophilia/diagnosis , Gnathostoma/immunology , Gnathostomiasis/diagnosis , Skin Diseases, Parasitic/diagnosisABSTRACT
Sparganosis is caused by the invasion of Spirometra sparganum into various tissues/organs. Subcutaneous sparganosis can be diagnosed by biopsy, while visceral/cerebral sparganosis is not easy to be diagnosed. The diagnosis depends largely on the detection of specific anti-sparganum antibodies. The specificity of the ELISA could be increased by using S. mansoni sparganum excretory-secretory [ES] antigens, but it also had the cross-reactions with sera of patients with cysticercosis or paragonimiasis. The aim of this study was to identify early specific diagnostic antigens in S. mansoni sparganum ES proteins. The sparganum ES proteins were analyzed by two-dimensional electrophoresis [2-DE] and Western blot probed with early sera from infected mice at 14 days post-infection. The immunoreactive protein spots were characterized by MALDI-TOF/ TOF-MS. A total of approximately 149 proteins spots were detected with isoelectric point [pI] varying from 3 to 7.5 and molecular weight from 20 to 115 kDa and seven protein spots with molecular weight of 23-31 kDa were recognized by the infection sera. Three of seven spots were successfully identified and characterized as the same S. mansoni protein [cysteine protease], and the proteins of other 4 spots were not included in the databases. The cysteine protease from S. mansoni ES proteins recognized by early infection sera might be the early diagnostic antigens for sparganosis
ABSTRACT
The first human case with trichinellosis was reported in 1964 in Tibet, China. However, up to the present, the etiological agent of trichinellosis has been unclear. The aim of this study was to identify a Tibet Trichinella isolate at a species level by PCR-based methods. Multiplex PCR revealed amplicon of the expected size (173 bp) for Trichinella spiralis in assays containing larval DNA from Tibet Trichinella isolate from a naturally infected pig. The Tibet Trichinella isolate was also identified by PCR amplification of the 5S ribosomal DNA intergenic spacer region (5S ISR) and mitochondrial large-subunit ribosomal RNA (mt-lsrDNA) gene sequences. The results showed that 2 DNA fragments (749 bp and 445 bp) of the Tibet Trichinella isolate were identical to that of the reference isolates of T. spiralis. The Tibet Trichinella isolate might be classifiable to T. spiralis. This is the first report on T. spiralis in southwestern China.