ABSTRACT
Objective To investigate the distribution characteristics of Oncomelania hupensis in Guangxi Zhuang Autonomous Region, so as to provide insights into the assessment of the risk of schistosomiasis transmission and the scientific formulation of the schistosomiasis surveillance strategy. Methods From 2015 to 2019, a total of 19 national schistosomiasis surveillance sites were assigned in Guangxi Zhuang Autonomous Region, including 4 fixed sites and 15 mobile sites. Snail survey was performed by means of systematic sampling in combination with environmental sampling, and the infection of Schistosoma japonicum was detected by the crushing method combined with loop-mediated isothermal amplification (LAMP) assay. Results From 2015 to 2019, snail habitats were detected at areas of 17 040 to 39 527 m2, including 6 214 m2 emerging snail habitats and 16 563 m2 re-emerging snail habitats. The overall mean density of living snails was 0.019 2 snails/0.1 m2 and the occurrence of frames with snails was 1.11% in the national schistosomiasis surveillance sites; however, no S. japonicum infection was identified in snails. The area of snail habitats increased by 121.46% in the national surveillance sites in 2019 as compared to that in 2015; however, 50.34% (Z = −0.422, P > 0.05) and 42.85% (χ2 = 130.41, P < 0.01) reductions were seen in the overall means density of living snails and the occurrence of frames with snails. All snail habitats were distributed in the 4 fixed surveillance sites, and were mainly found in ditches, paddy fields and dry lands, with weeds as the primary vegetation type. Conclusions There are still risk factors leading to re-emergent transmission of schistosomiasis in Guangxi Zhuang Autonomous Region, such as local snail spread, and the monitoring of schistosomiasis remains to be reinforced to further consolidate the achievements of schistosomiasis elimination in the region.
ABSTRACT
Objective To understand Clonorchis sinensis infections in cats in Nanning City, so as to provide evidence for the control of the reservoir host of C. sinensis. Methods The cat livers were purchased from cat slaughterhouses in Nanning City. The cat gallbladder and liver were dissected, and liver flukes were collected and counted. Then, the worms were subjected to morphological observation, amplification of the ITS2 gene and sequencing. The species of the worms were identified using BLAST. Results A total of 105 cat livers were collected from two cat slaughterhouses, and 68 were detected with C. sinensis infections, with an infection rate of 64.76%. The highest burden was 980 worms in a single liver, and the mean burden was 72 worms in a liver. There were 3 types of liver flukes with various size and morphology, and all were identified as C. sinensis by means of morphological observation, ITS2 gene amplification, sequencing and sequence alignment. Conclusion There is a high infection rate of C. sinensi in marketed cats in Nanning City, and it is therefore suggested that targeted interventions should be intensified for the management of C. sinensis infections in cats.
ABSTRACT
Objective To understand Clonorchis sinensis infections in cats in Nanning City, so as to provide evidence for the control of the reservoir host of C. sinensis. Methods The cat livers were purchased from cat slaughterhouses in Nanning City. The cat gallbladder and liver were dissected, and liver flukes were collected and counted. Then, the worms were subjected to morphological observation, amplification of the ITS2 gene and sequencing. The species of the worms were identified using BLAST. Results A total of 105 cat livers were collected from two cat slaughterhouses, and 68 were detected with C. sinensis infections, with an infection rate of 64.76%. The highest burden was 980 worms in a single liver, and the mean burden was 72 worms in a liver. There were 3 types of liver flukes with various size and morphology, and all were identified as C. sinensis by means of morphological observation, ITS2 gene amplification, sequencing and sequence alignment. Conclusion There is a high infection rate of C. sinensi in marketed cats in Nanning City, and it is therefore suggested that targeted interventions should be intensified for the management of C. sinensis infections in cats.