Occurrence and transmission of the Newcastle Disease Virus aerosol originating from infected chickens under experimental condition
Session I: Chai, Tong Jie
Title of Contribution: Occurrence and transmission of the Newcastle Disease Virus aerosol originating from infected chickens under experimental condition
Author(s): Xiao Xia LI a, Tong Jie CHAI a*, Zhi Liang WANG b, Cui Ping SONG b,
Hong Jing CAO b, Jing Bo LIU a, Xing Xiao ZHANG a, Wei Wang a
Affiliation(s): a College of Animal Science and Veterinary Medicine, Shandong Agricultural
University, Research Center for Animal Disease Control Engineering,
Shandong Province, Tai'an, 271018, China
b National Reference Laboratory for Newcastle Diseases, Center of Animal health and
epidemiology, Ministry of Agriculture, Qingdao 266032, China
*Corresponding author at: College of Animal Science and Veterinary Medicine,
Shandong Agricultural University, Research Center for Animal Disease Control
Engineering, Shandong Province, Tai'an, 271018, China
Tel.: +86 5388241503; fax: +86 538 8241419.
E-mail address: chaitj117@163.com
Abstract:
Airborne transmission is one of the important routes for spread of the
Newcastle Disease (ND). However, there was remarkably little experimental evidence.
In order to better understand this transmission route, a model system was established
and two trials were conducted. Twenty-five Specific pathogen-free chickens (SPF)
were inoculated with ND Virus (NDV) and were accommodated in one isolator. Six
days after the SPF were challenged, fifteen chickens were placed into another isolator
which received its air supply from the first isolator. The NDV aerosol originating
from inoculated chickens were collected with All Glass Impinger-30 (AGI-30) to
studied the concentration of NDV aerosol. The antibody response to infection was
assessed by the hemagglutination inhibition test (HI-T) and the viral shedding was
detected by RT-PCR and Dot-ELISA. Airborne NDV was detectable by RT-PCR and
was isolated within 3 days post-inoculation (dpi) and the aerosol concentration
reached a peak at 1.69 × 104 PFU/m3ÿair at 11-13 dpi and was consistently detectable
up to 40 dpiÿat 6.98 × 103 PFU/m3. NDV shedding was detectable from inoculated
chickens of 2 dpi to 40 dpi and from 6 days post-aerosol exposure infection (dpi) to
33 dpi of aerosol exposure chickens. Viral strain induced high antibody level, both in
inoculated and in aerosol exposure chickens. Airborne transmission did occur, as
shown by NDV shedding and seroconverted to NDV in aerosol exposure chickens.
The results indicated that virus shed form infected chickens could be aerosolized and
airborne transmission of NDV is feasible. This is the first report on occurrence,
quantification and transmission of airborne NDV under experimental conditions.
