title: Kinetics of viral loads and genotypic analysis of elephant endotheliotropic herpesvirus-1 infection in captive Asian elephants (Elephas maximus).
abstract: Elephant endotheliotropic herpesviruses (EEHVs) can cause fatal hemorrhagic disease in juvenile Asian elephants (Elphas maximus); however, sporadic shedding of virus in trunk washes collected from healthy elephants also has been detected. Data regarding the relationship of viral loads in blood compared with trunk washes are lacking, and questions about whether elephants can undergo multiple infections with EEHVs have not been addressed previously. Real-time quantitative polymerase chain reaction was used to determine the kinetics of EEHV1 loads, and genotypic analysis was performed on EEHV1 DNA detected in various fluid samples obtained from five Asian elephants that survived detectable EEHV1 DNAemia on at least two separate occasions. In three elephants displaying clinical signs of illness, preclinical EEHV1 DNAemia was detectable, and peak whole-blood viral loads occurred 3-8 days after the onset of clinical signs. In two elephants with EEHV1 DNAemia that persisted for 7-21 days, no clinical signs of illness were observed. Detection of EEHV1 DNA in trunk washes peaked approximately 21 days after DNAemia, and viral genotypes detected during DNAemia matched those detected in subsequent trunk washes from the same elephant. In each of the five elephants, two distinct EEHV1 genotypes were identified in whole blood and trunk washes at different time points. In each case, these genotypes represented both an EEHV1A and an EEHV1B subtype. These data suggest that knowledge of viral loads could be useful for the management of elephants before or during clinical illness. Furthermore, sequential infection with both EEHV1 subtypes occurs in Asian elephants, suggesting that they do not elicit cross-protective sterilizing immunity. These data will be useful to individuals involved in the husbandry and clinical care of Asian elephants.
authors.affiliation: Department of Molecular Virology and Microbiology, One Baylor Plaza, Baylor College of Medicine, Houston, Texas 77030, USA.
authors.forename: Jeffrey J
authors.initials: JJ
authors.lastname: Stanton
authors.forename: Jian-Chao
authors.initials: JC
authors.lastname: Zong
authors.forename: Crystal
authors.initials: C
authors.lastname: Eng
authors.forename: Lauren
authors.initials: L
authors.lastname: Howard
authors.forename: Joe
authors.initials: J
authors.lastname: Flanagan
authors.forename: Martina
authors.initials: M
authors.lastname: Stevens
authors.forename: Dennis
authors.initials: D
authors.lastname: Schmitt
authors.forename: Ellen
authors.initials: E
authors.lastname: Wiedner
authors.forename: Danielle
authors.initials: D
authors.lastname: Graham
authors.forename: Randall E
authors.initials: RE
authors.lastname: Junge
authors.forename: Martha A
authors.initials: MA
authors.lastname: Weber
authors.forename: Martha
authors.initials: M
authors.lastname: Fischer
authors.forename: Alicia
authors.initials: A
authors.lastname: Mejia
authors.forename: Jie
authors.initials: J
authors.lastname: Tan
authors.forename: Erin
authors.initials: E
authors.lastname: Latimer
authors.forename: Alan
authors.initials: A
authors.lastname: Herron
authors.forename: Gary S
authors.initials: GS
authors.lastname: Hayward
authors.forename: Paul D
authors.initials: PD
authors.lastname: Ling
mesh_terms: D000818:Animals; D000836:Animals, Zoo; D004606:Elephants; D005260:Female; D005838:Genotype; D006566:Herpesviridae Infections / Q000662:veterinary* / Q000821:virology; D008297:Male; D010802:Phylogeny; D011247:Pregnancy; D013997:Time Factors; D018140:Varicellovirus / Q000145:classification* / Q000235:genetics*; D019562:Viral Load