A novel antigen capture ELISA for the specific detection of IgG antibodies to elephant endotheliotropic herpes virus.
BACKGROUND
Elephants are classified as critically endangered animals by the International Union for Conservation of Species (IUCN). Elephant endotheliotropic herpesvirus (EEHV) poses a large threat to breeding programs of captive Asian elephants by causing fatal haemorrhagic disease. EEHV infection is detected by PCR in samples from both clinically ill and asymptomatic elephants with an active infection, whereas latent carriers can be distinguished exclusively via serological assays. To date, identification of latent carriers has been challenging, since there are no serological assays capable of detecting seropositive elephants.


RESULTS
Here we describe a novel ELISA that specifically detects EEHV antibodies circulating in Asian elephant plasma/serum. Approximately 80 % of PCR positive elephants display EEHV-specific antibodies. Monitoring three Asian elephant herds from European zoos revealed that the serostatus of elephants within a herd varied from non-detectable to high titers. The antibody titers showed typical herpes-like rise-and-fall patterns in time which occur in all seropositive animals in the herd more or less simultaneously.


CONCLUSIONS
This study shows that the developed ELISA is suitable to detect antibodies specific to EEHV. It allows study of EEHV seroprevalence in Asian elephants. Results confirm that EEHV prevalence among Asian elephants (whether captive-born or wild-caught) is high.
ViroScience Lab, Erasmus Medical Center, Erasmus MC, Room Ee1714, dr. Molewaterplein 50, 3015, GE, Rotterdam, The Netherlands. p.vandendoel@erasmusmc.nl.
Petra B
PB
van den Doel
VISAVET Centre, Animal Health Department, Complutense University of Madrid, Madrid, Spain. vrguezprieto@hotmail.com.
Víctor Rodríguez
VR
Prieto
Department of Genetics, Erasmus Medical Center, Rotterdam, The Netherlands. s.vanrossum-fikkert@erasmusmc.nl.
Sarah E
SE
van Rossum-Fikkert
Veterinary services, Rotterdam Zoo, Rotterdam, The Netherlands. w.schaftenaar@rotterdamzoo.nl.
Willem
W
Schaftenaar
Smithsonian Conservation Biology Institute, Smithsonian's National Zoo, Washington, DC, USA. LatimerE@si.edu.
Erin
E
Latimer
Department of Animal Health, Houston Zoo, Inc., Houston, TX, USA. lhoward@houstonzoo.org.
Lauren
L
Howard
East-Midland Zoological Society, Twycross Zoo, Warwickshire, UK. sarah.chapman@twycrosszoo.org.
Sarah
S
Chapman
Veterinary Services, Zoological Society of London, London, UK. Nic.Masters@zsl.org.
Nic
N
Masters
ViroScience Lab, Erasmus Medical Center, Erasmus MC, Room Ee1714, dr. Molewaterplein 50, 3015, GE, Rotterdam, The Netherlands. a.osterhaus@erasmusmc.nl.|Artemis One Health Research Institute, Utrecht, The Netherlands. a.osterhaus@erasmusmc.nl.
Albert D M E
AD
Osterhaus
Department of Molecular Virology and Microbiology, Baylor's College of Medicine, Houston, TX, USA. pling@bcm.edu.
Paul D
PD
Ling
Animal and Plant Health Agency, Addlestone, UK. Akbar.Dastjerdi@apha.gsi.gov.uk.
Akbar
A
Dastjerdi
ViroScience Lab, Erasmus Medical Center, Erasmus MC, Room Ee1714, dr. Molewaterplein 50, 3015, GE, Rotterdam, The Netherlands. b.martina@erasmusmc.nl.|Artemis One Health Research Institute, Utrecht, The Netherlands. b.martina@erasmusmc.nl.
Byron
B
Martina
D000818:Animals; D000836:Animals, Zoo; D000914:Antibodies, Viral / Q000097:blood*; D003001:Cloning, Molecular; D004606:Elephants; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods / Q000662:veterinary*; D005060:Europe / Q000453:epidemiology; D005260:Female; D006564:Herpesviridae / Q000276:immunology / Q000302:isolation & purification*; D006566:Herpesviridae Infections / Q000175:diagnosis / Q000662:veterinary* / Q000821:virology; D007074:Immunoglobulin G / Q000302:isolation & purification*; D008297:Male; D012680:Sensitivity and Specificity; D014759:Viral Envelope Proteins / Q000235:genetics / Q000378:metabolism
D000914:Antibodies, Viral; D007074:Immunoglobulin G; D014759:Viral Envelope Proteins