Geology topics

Ying Liu

Publications and source records attributed to Ying Liu.

3 recordsLinked to original sources

USGS2018

Insight into infectious hematopoietic necrosis virus (IHNV) in Chinese rainbow trout aquaculture from virus isolated from 7 provinces in 2010–2014

The aquatic rhabdovirus infectious hematopoietic necrosis virus (IHNV) currently causes substantial fish losses in Chinese coldwater aquaculture. While IHNV was first reported in China in 1985 and has since undergone considerable spread, little is known about the underlying epidemiological patterns like introduction sources and transmission routes. In this study, we examined epidemiological and phylogenetic data for 50 IHNV isolates from 7 provinces in China detected in 2010–2014 (Liaoning, n = 33; Jilin, n = 3; Heilongjiang, n = 1; Yunnan, n = 2; Sichuan, n = 1; Hebei, n = 5; Gansu, n = 5). Features of case details include highest mortality associated with water temperatures of 8–10 °C and symptomatic disease observed in adult rainbow trout. Sequence comparisons of the midG sequences of 50 strains revealed 11 different sequence types. One sequence type, mG801J, was predominantly detected, being found in 38 of 50 isolates. Phylogenetic analyses of the new midG sequence types showed that 49 of 50 IHNV isolates are closely related to one another and all descend from the previously described J Nagano subgroup, forming the monophyletic group J Nagano-China clade . This indicates that the majority of IHNV circulating within China is descended from a single importation event from elsewhere in Asia. The one observed exception was the detection of a novel genotype belonging to the previously described MN subgroup. This genotype was identified in Liaoning province, and indicates a second introduction event, one that does not appear to have resulted in diversification and spread. These results indicate that continued surveillance of IHNV in China is necessary to understand and manage viral transmission dynamics within China over time.

Aquaculture↗

USGS2015

Movement analysis of free-grazing domestic ducks in Poyang Lake, China: A disease connection

Previous work suggests domestic poultry are important contributors to the emergence and transmission of highly pathogenic avian influenza throughout Asia. In Poyang Lake, China, domestic duck production cycles are synchronized with arrival and departure of thousands of migratory wild birds in the area. During these periods, high densities of juvenile domestic ducks are in close proximity to migratory wild ducks, increasing the potential for the virus to be transmitted and subsequently disseminated via migration. In this paper, we use GPS dataloggers and dynamic Brownian bridge models to describe movements and habitat use of free-grazing domestic ducks in the Poyang Lake basin and identify specific areas that may have the highest risk of H5N1 transmission between domestic and wild birds. Specifically, we determine relative use by free-grazing domestic ducks of natural wetlands, which are the most heavily used areas by migratory wild ducks, and of rice paddies, which provide habitat for resident wild ducks and lower densities of migratory wild ducks. To our knowledge, this is the first movement study on domestic ducks, and our data show potential for free-grazing domestic ducks from farms located near natural wetlands to come in contact with wild waterfowl, thereby increasing the risk for disease transmission. This study provides an example of the importance of movement ecology studies in understanding dynamics such as disease transmission on a complicated landscape.

Poyang Lake↗

USGS2014

Risks of avian influenza transmission in areas of intensive free-ranging duck production with wild waterfowl

For decades, southern China has been considered to be an important source for emerging influenza viruses since key hosts live together in high densities in areas with intensive agriculture. However, the underlying conditions of emergence and spread of avian influenza viruses (AIV) have not been studied in detail, particularly the complex spatiotemporal interplay of viral transmission between wild and domestic ducks, two major actors of AIV epidemiology. In this synthesis, we examine the risks of avian influenza spread in Poyang Lake, an area of intensive free-ranging duck production and large numbers of wild waterfowl. Our synthesis shows that farming of free-grazing domestic ducks is intensive in this area and synchronized with wild duck migration. The presence of juvenile domestic ducks in harvested paddy fields prior to the arrival and departure of migrant ducks in the same fields may amplify the risk of AIV circulation and facilitate the transmission between wild and domestic populations. We provide evidence associating wild ducks migration with the spread of H5N1 in the spring of 2008 from southern China to South Korea, Russia, and Japan, supported by documented wild duck movements and phylogenetic analyses of highly pathogenic avian influenza H5N1 sequences. We suggest that prevention measures based on a modification of agricultural practices may be implemented in these areas to reduce the intensity of AIV transmission between wild and domestic ducks. This would require involving all local stakeholders to discuss feasible and acceptable solutions.

Poyang Lake↗