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Deng Z.-H.,Institute of Parasitic Diseases | Zhang Q.-M.,Institute of Parasitic Diseases | Huang S.-Y.,Institute of Parasitic Diseases | Jones J.L.,Centers for Disease Control and Prevention
Tropical Medicine and International Health | Year: 2012

The rat lungworm Angiostrongylus cantonensis is a zoonotic nematode with a wide distribution. We report the first provincial survey of the prevalence of A. cantonensis infection among wild rodents and snails in Guangdong Province, China. A total of 2929 Pomacea canaliculata and 1354 Achatina fulica were collected from fields in 22 survey sites with a larval infection rates ranging from 0-26.6% to 0-45.4%. In addition, 114 Cipangopaludina sp and 252 Bellamya sp were bought from markets; larvae were found only in Bellamya snails from two survey sites with an infection rate of 1.4% (1/70) and 3.3% (3/91), respectively. Four hundred and ninety-one rodents were captured in nine sites (Rattus norvegicus, R. flavipectus, Suncus murinus, Mus musculus, Bandicota indica, R. losea and R. rattus). Adult worms were found in R. norvegicus, R. flavipectus and Bandicota indica. Our survey revealed a wide distribution of A. cantonensis and its intermediate hosts P. canaliculata and A. fulica in Guangdong. The prevalence of A. cantonensis in wild snails and rats poses a substantial risk for angiostrongyliasis in humans. © 2011 Blackwell Publishing Ltd.


De-jian S.,Institute of Parasitic Diseases | Xu-li D.,Shandong Institute of Parasitic Diseases | Ji-hui D.,U.S. Center for Disease Control and Prevention
Infectious Diseases of Poverty | Year: 2013

China used to be one of the most heavily endemic countries for lymphatic filariasis (LF) in the world. There were 864 endemic counties/cities in 16 provinces/autonomous regions/municipalities (P/A/M) with a total population of 330 million at risk of infection. Since the founding of the People's Republic of China in 1949, the Chinese Government has designated the control of the disease to be a top priority. Due to decades of sustained efforts, close cooperation related to LF control among government departments, and active participation of endemic populations, an all-round campaign for prevention and control has been carried out vigorously and successfully. Over many years, great achievements have been made through persistent endeavors of Chinese scientists and disease control workers. The ultimate goal to eliminate LF in the country was achieved in 2006. © 2013 De-jian et al.; licensee BioMed Central Ltd.


Fung M.S.,University of California at Berkeley | Xiao N.,Institute of Parasitic Diseases | Xiao N.,National Institute of Parasitic Diseases | Xiao N.,Collaborating Center for Malaria | And 2 more authors.
American Journal of Tropical Medicine and Hygiene | Year: 2012

Sensitive Schistosoma japonicum detection methods are needed to progress from schistosomiasis control to elimination. The sensitivity of the Kato-Katz thick smear and miracidium hatching tests decrease with infection intensity and serological tests cannot always identify current infections. We evaluated a fecal polymerase chain reaction (PCR) assay to detect S. japonicum infection in 106 humans and 8 bovines in China. PCR was highly sensitive, detecting S. japonicum DNA at 0.5 eggs/g of stool. Comparing PCR examination of a single stool sample to the miracidium hatching test using three consecutive stool samples, more humans were hatching test positive (20%) than PCR positive (15%). However, two individuals were PCR positive in a village where no infections were detected by coprological methods. The sensitivity of PCR makes it a promising tool for schistosomiasis diagnostics and screening, although egg shedding variability and stool sample size present challenges for any detection method in low-transmission areas. Copyright © 2012 by The American Society of Tropical Medicine and Hygiene.


Amin O.M.,Institute of Parasitic Diseases | Evans P.,Brigham Young University | Heckmann R.A.,Brigham Young University | El-Naggar A.M.,Brigham Young University | El-Naggar A.M.,Ain Shams University
Parasitology Research | Year: 2013

Mediorhynchus africanus n. sp. is described from specimens collected from the helmeted guinea fowls, Numida meliagris Linn. 1758 in Kruger National Park and elsewhere in subSaharan Africa from the same and other galliform birds. These specimens were previously assigned to Mediorhynchus gallinarum Bhaleroa (Proc Zool Soc Lond Ser B Syst Morph 107:199-203, 1937) described from chickens, Gallus gallus L. in India and subsequently reported from other Asian countries. The identification of the African forms as M. gallinarum was based on similarities in the structure and measurements of the proboscis, proboscis armature and receptacle, lemnisci, and reproductive organs. A detailed study of specimens from South Africa and descriptions reported from elsewhere in Africa revealed marked differences that clearly distinguish the African material as new species. The African specimens are pseudo-segmented and flattened, the proboscis has two prominent apical pores, sensory pits are prevalent throughout the trunk, the posterior end of the female is broad with dorso-terminal dome-like extension opposite the subterminal gonopore, and the eggs are large. The Asian specimens from Indonesia and elsewhere are cylindrical and non-segmented, the proboscis lacks prominent apical pores, sensory pits are rare on the trunk, the posterior end of the female is pointed with a terminal gonopore, and the eggs are markedly smaller. We used DNA sequence from one mitochondrial gene (cytochrome oxidase subunit I) and one nuclear gene (18S ribosomal RNA) to infer the phylogenetic relationships of M. africanus and M. gallinarum and selected Acanthocephala. Medioryhnchus is monophyletic and M. africanus and M. gallinarum are allopatric sister species (9.7 % sequence divergence). All findings indicate that M. africanus should be ranked as a separate species. © 2013 Springer-Verlag Berlin Heidelberg.


Boufana B.,University of Salford | Qiu J.,Institute of Parasitic Diseases | Chen X.,Institute of Parasitic Diseases | Budke C.M.,Texas A&M University | And 2 more authors.
Acta Tropica | Year: 2013

Echinococcus shiquicus was discovered in foxes and pika wildlife hosts in Sichuan Province, China in 2005. Faecal samples from dogs collected in a previous echinococcosis purgation survey from Shiqu County, Ganzi Tibetan Autonomous Prefecture (Sichuan) were screened by coproPCR to investigate the possible occurrence of E. shiquicus. In addition, coproDNA extracted from 8 necropsied Tibetan foxes (. Vulpes ferrilata), the natural host of E. shiquicus, were also included. Thirty (6/20) percent of faecal samples from dogs were positive for E. shiquicus DNA after PCR amplification of a fragment within the ND1 mitochondrial gene. Echinococcus shiquicus was confirmed by sequencing in four dogs and 3 of the 6 dogs were concurrently infected with E. multilocularis. These were also verified by sequencing. Faecal samples from two Tibetan foxes were shown by PCR to harbour both E. multilocularis and E. shiquicus DNA. One of these dual E. multilocularis and E. shiquicus infections in a Tibetan fox was confirmed by sequencing. © 2013 Elsevier B.V.


Amin O.M.,Institute of Parasitic Diseases | Ha N.V.,Vietnam Academy of Science and Technology | Ha D.N.,Institute of Ecology and Biological Science
Parasite | Year: 2011

The occurrence of acanthocephalans of the genus Neoechinorhynchus Stiles and Hassall, 1905 in Vietnamese waters is reported for the first time. Six new species are described from seven species of marine fish of the families Belonidae, Clupeidae, Megalopidae, Mugilidae, and Sciaenidae, collected in Halong Bay of the eastern seaboard of Vietnam in 2008 and 2009. These are Neoechinorhynchus (Neoechinorhynchus) plaquensis n. sp. characterized by dermal plaques covering the entire trunk; Neoechinorhynchus manubriensis n. sp. with very long anterior proboscis hooks having roots with prominent anterior manubria and very small and equal middle and posterior hooks, two pseudoretractors in the receptacle, simple vagina, and terminal gonopore; Neoechinorhynchus pennahia n. sp. with equal anterior and middle proboscis and somewhat smaller posterior hooks, and terminal female gonopore; Neoechinorhynchus ampullata with many giant nuclei in the body wall and lemnisci and a parareceptacle structure complex which includes pumping ampullas reported for the first time; Neoechinorhynchus (Neoechinorhynchus) longinucleatus n. sp. with very long giant nuclei in the Lemnisci, anteriorly twisted vagina, and subterminal female gonopore. Neoechinorhynchus (Neoechinorhynchus) ascus n. sp. is the second species of Neoechinorhynchus found with the parareceptacle structure/ampulla complex. Neoechinorhynchus (Neoechinorhynchus) johnii Yamaguti, 1929 of Bilqees, 1972 is not W johnii because of proboscis armature and other discrepancies with the Yamaguti material. Notes on host distribution and feeding habits are also included.


Amin O.M.,Institute of Parasitic Diseases | Van Ha N.,Vietnam Academy of Science and Technology
Parasitology Research | Year: 2011

Four species of echinorhynchid acanthocephalans were collected from marine fish off Cat Ba Island, Halong Bay, Gulf of Tonkin, Vietnam, in the spring of 2009. Acanthocephalus halongensis n. sp. (Echinorhynchidae) from the redtail scad, Decapterus kurroides Bleeker 1855 (Carangidae), has a unique proboscis armature with a spiniform basal hook with lateral root and an incomplete receptacle wall posteriorly. Gorgorhynchus tonkinensis n. sp. (Rhadinorhynchidae) also from D. kurroides, has long, slender, winding lemnisci, many epidermal nuclei, and a narrow anterior trunk with a shoulder armed with 20 circles of tightly packed spines, the posterior four circles of which have abruptly larger spines than those in the anterior circles. Neorhadinorhynchus atypicalis n. sp. (Cavisomidae) from the rabbitfish, Siganus fuscescens (Houttuyn 1782) (Siganidae), has the largest number of proboscis hooks per row, testes wider than long, and four clustered cement glands. Micracanthorhynchica kuwaitensis Amin and Sey 1996 (Rhadinorhynchidae) from the spottail needlefish Strongylura strongylura (van Hasselt 1823) (Belonidae) was similar to specimens originally described from the Arabian Gulf off the Kuwaiti coast. These acanthocephalans were collected in small numbers but stood out as uniquely and considerably different from their closest relatives to warrant their reporting. All species of acanthocephalans and their host and geographic distribution are described, and a key to the species of Gorgorhynchus is provided. © 2011 Springer-Verlag.


Xiao N.,Institute of Parasitic Diseases
Zhongguo ji sheng chong xue yu ji sheng chong bing za zhi = Chinese journal of parasitology & parasitic diseases | Year: 2012

To find an effective strategy of implementing health education in Tibetan Regions so as to make echinococcosis control sustainable at a large scale. During July to November of 2008, surveys were conducted on health education requirements among various populations in the form of questionnaire and group discussion in endemic areas of echinococcosis in three counties of the Ganzi Tibetan Autonomous Prefecture, Sichuan. Based on the obtained results, health education materials suitable for different populations were designed. The materials were applied for conducting health education in field at Tagong Township, Kangding of Ganzi in October, 2009. By the survey in May, 2010, the improved effect on knowledge and behavior change was compared before and after (6 months later) health education in order to assess the usefulness of these materials. Simultaneously, Xinduqiao Township of Kangding was selected as control. This town is neighboring to the study area with similar natural and demographic conditions, in which no health education activities related to the study was implemented. Various populations showed their interested requirements for health education materials and ways. Based on the information collected, a series of materials were designed and applied for health education activities in field. The results indicated that, compared with the data before health education, improvement of the knowledge and behaviors against echinococcosis among students and local residents showed significant increase (P < 0.05), but only one knowledge point about the importance of washing hands before meal among students showed no significant difference (P > 0.05) in spite of the rates increasing from 88.6% (78/88) before health education to 95.5% (84/88) after education. The local officers and monks also showed to some extent improvement on behavior manners. The rate of correct treatment of livestock viscera increased from 37.1% (13/35) and 30.3% (10/33) before the education to 82.9% (29/35) and 78.8% (26/33) (P < 0.01), while the rate of not feeding stray dogs among monks was 6.4% (3/47) before and 10.6% (5/47) (P > 0.05) after the education. The knowledge-increasing and behavior-improving rates on playing dogs among the students, residents and monks increased by 182% and 193%, 42.8% and 54.3%, 6.4% and 14.9%, respectively. There was no considerable change in the control township. The materials designed for health education are acceptable by most populations. The improvement rate of knowledge and behaviors is considerable among the groups. Use of the materials receives expected effect on health education and health promotion.


Carlton E.J.,University of California at Berkeley | Bates M.N.,University of California at Berkeley | Zhong B.,Institute of Parasitic Diseases | Seto E.Y.W.,University of California at Berkeley | Spear R.C.,University of California at Berkeley
PLoS Neglected Tropical Diseases | Year: 2011

Background: Schistosomiasis has reemerged in China, threatening schistosomiasis elimination efforts. Surveillance methods that can identify locations where schistosomiasis has reemerged are needed to prevent the further spread of infections. Methods and Principal Findings: We tested humans, cows, water buffalo and the intermediate host snail, Oncomelania hupensis, for Schistosoma japonicum infection, assessed snail densities and extracted regional surveillance records in areas where schistosomiasis reemerged in Sichuan province. We then evaluated the ability of surveillance methods to identify villages where human infections were present. Human infections were detected in 35 of the 53 villages surveyed (infection prevalence: 0 to 43%), including 17 of 28 villages with no prior evidence of reemergence. Bovine infections were detected in 23 villages (infection prevalence: 0 to 65%) and snail infections in one village. Two common surveillance methods, acute schistosomiasis case reports and surveys for S. japonicum-infected snails, grossly underestimated the number of villages where human infections were present (sensitivity 1% and 3%, respectively). Screening bovines for S. japonicum and surveys for the presence of O. hupensis had modest sensitivity (59% and 69% respectively) and specificity (67% and 44%, respectively). Older adults and bovine owners were at elevated risk of infection. Testing only these high-risk human populations yielded sensitivities of 77% and 71%, respectively. Conclusions: Human and bovine schistosomiasis were widespread in regions where schistosomiasis had reemerged but acute schistosomiasis and S. japonicum-infected snails were rare and, therefore, poor surveillance targets. Until more efficient, sensitive surveillance strategies are developed, direct, targeted parasitological testing of high-risk human populations should be considered to monitor for schistosomiasis reemergence. © 2011 Carlton et al.


Seto E.Y.W.,University of California at Berkeley | Wong B.K.,University of California at Berkeley | Lu D.,Institute of Parasitic Diseases | Zhong B.,Institute of Parasitic Diseases
American Journal of Tropical Medicine and Hygiene | Year: 2011

The efficacy of praziquantel for the treatment of Schistosoma japonicum in humans is reported from a crosssectional survey conducted in 33 villages in Sichuan Province. Infection prevalence was found to be 5.7% (185 infected of 3,269 tested) in a region where 44-73% prevalence was found 9 years before. Collected miracidia were subjected to an in vitro test of praziquantel susceptibility. An effective concentration of praziquantel associated with 50% of miracidia changing shape was found between 10 -8 and 10 -7 M and 10 -7 and 10 -6 M for 10 and 5 minutes of exposure, respectively. After treating infected persons two times with 40-mg/kg doses of praziquantel, only one remained infected. Findings are reported from a 60-household questionnaire on attitudes and behaviors that may be associated with development of drug resistance. The low number of treatment failures and good compliance with treatment despite side effects and repeated annual treatments suggest that, in the near term, praziquantel remains effective in treating human S. japonicum infection in China. Copyright © 2011 by The American Society of Tropical Medicine and Hygiene.

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