ABSTRACT
A 23-year-old female residing in a village of Cao Bang Province, North Vietnam, visited the Hospital of Hanoi Medical University in July 2013. She felt dim eyes and a bulge-sticking pain in her left eye for some days before visiting the hospital. In the hospital, a clinical examination, an eye endoscopy, and an operation were carried out. A nematode specimen was collected from the eye of this patient. The body of this worm was thin and long and measured 22.0x0.3 mm. It was morphologically suggested as an immature female worm of Angiostrongylus cantonensis. By a molecular method using 18S rRNA gene, this nematode was confirmed as A. cantonensis. This is the first molecular study for identification of A. cantonensis in Vietnam.
Subject(s)
Animals , Female , Humans , Young Adult , Angiostrongylus cantonensis/classification , Base Sequence , Eye/parasitology , Eye Diseases/diagnosis , Molecular Sequence Data , Strongylida Infections/diagnosis , VietnamABSTRACT
Angiostrongylus cantonensis is the etiologic agent of eosinophilic meningoencephalitis in humans. Cases have been recorded in many parts of the world, including Brazil. The aim of this study was to compare the differences in the biology and morphology of two different Brazilian haplotypes of A. : ac8 and ac9. A significantly larger number of L1 larvae eliminated in the faeces of rodents at the beginning of the patent period was observed for ac9 haplotype and compared to the total of L1 larvae eliminated, there was a significant difference between the two haplotypes. The ac9 haplotype showed a significant difference in the proportion of female and male specimens (0.6:1), but the same was not observed for ac8 (1.2:1). The morphometric analysis showed that male and female specimens isolated from ac8 haplotype were significantly larger with respect to body length, oesophagus length, spicule length (male) and distance from the anus to the rear end (female) compared to specimens from ac9. The morphological analysis by light microscopy showed little variation in the level of bifurcations at the lateral rays in the right lobe of the copulatory bursa between the two haplotypes. The biological, morphological and morphometric variations observed between the two haplotypes agree with the observed variation at the molecular level using the cytochrome oxidase subunit I marker and reinforce the possible influence of geographical isolation on the development of these haplotypes.
Subject(s)
Animals , Female , Male , Angiostrongylus cantonensis/anatomy & histology , Body Size/genetics , Electron Transport Complex IV/genetics , Angiostrongylus cantonensis/classification , Angiostrongylus cantonensis/genetics , Brazil , Feces/parasitology , Geography, Medical , Haplotypes , Larva/genetics , Microscopy, Polarization , Rats, Wistar , Sex Ratio , Time Factors , TranscriptomeABSTRACT
Five subspecies of Oncomelania snails, Oncomelania hupensis nosophora, O.h. hupensis, O.h.chiui, O.h.formosana and O.h.quadrasi, were experimentally exposed to the first stage larvae of Angiostrongylus cantonesis. The presence of third stage larvae was observed in all of the five subspecies of Oncomelania snails 20 days after infection. Infection rates of the third stage larvae of the parasite in Oncomelania snails were 38.0-40.0%. There were no differences in preferences among Oncomelania snails. The third stage larvae in Oncomelania snails almost distributed in kidney and intestine region, and most of the larvae were active and free in tissues. The distribution pattern of the larvae in Oncomelania snails was quite different from that in Achatina fulica and Ampullarium sp. These third stage larvae were ingested by rats, and developed to adults. These data suggest that Oncomelania snails may play important role when A. cantonensis will spread, and indicate the possibility of human infection with A. cantonensis.