style="font-size:15px;"> Virus neutralization tests have been used for the detection of antibodies against TeHV1 and 3 in tortoises.
An ELISA has also been described for the detection of antibodies against these two viruses and against TeHV2, but may not be commercially available.
PATHOLOGICAL FINDINGS
Ballooning degeneration and necrosis may be noted in infected epithelial cells, necrosis and inflammation in affected tissues.
Fibropapillomas consist of a hyperplastic epidermis and a thickened hypercellular dermis.
Infected cells may contain eosinophilic to amphophilic intranuclear inclusions.
APPROPRIATE HEALTH CARE
There are no standardized protocols for treating HV‐infected reptiles.
Strict quarantine, biosecurity, and hygiene are essential for the prevention of HV infections.
Autovaccination with inactivated material from surgically removed fibropapillomas has been suggested.
Keeping animals at the high end of their POTZ may help in recovery, as well as treatment of secondary bacterial infections.
NUTRITIONAL SUPPORT
Herpesvirus infected reptiles may be anorexic and nutritional support may be necessary.
In animals with oral lesions, esophagostomy tubes may be necessary.
CLIENT EDUCATION/HUSBANDRY RECOMMENDATIONS
Testing for both virus and antibodies (in tortoises) should be in place.
An effective quarantine regimen should be in place.
Mixing of tortoise species should be avoided.
Infected animals must be isolated
SURGICAL CONSIDERATIONS
For fibropapillomas—surgical removal of lesions.
DRUG(S) OF CHOICE
Acyclovir 80 mg/kg PO q24h (famciclovir has been shown to be safer in mammals and may be an alternative choice for treatment).
Acyclovir topically on lesions or topical disinfection (e.g., with 0.5% chlorhexidine solution) have also been suggested.
The use of immunomodulators (e.g., Zylexis (Pfizer AG, Zurich, Switzerland)) has been suggested in HV infected tortoises, but its efficacy is unproven.
PRECAUTIONS/INTERACTIONS
Affected animals should be barrier nursed and in‐contact animals should be placed in quarantine.
PATIENT MONITORING
Development of disease in contact animals may take several weeks, so monitoring of a collection (and barrier nursing of contact animals) should remain active for at least one season.
There is some indication that brumation may provoke disease outbreaks, and intensified health monitoring should be carried out in the spring and again before the next brumation.
EXPECTED COURSE AND PROGNOSIS
Morbidity and mortality can be high, depending on the virus strain and host species involved, although it can take an extended period of time for the disease to run its course within a collection.
Surviving animals remain carriers
COMMENTS
N/A
ZOONOTIC POTENTIAL
Herpesviruses of reptiles have not been shown to be zoonotic.
SYNONYMS
Fibropapillomatosis (FP) in sea turtles
ABBREVIATIONS
chHV5 = chelonid alphaherpesvirus 5
CNS = central nervous system
ELISA = enzyme‐linked immunosorbent assay
FPTHV = fibropapillomatosis‐associated turtle herpesvirus
HV = herpesvirus
LETD = lung = eye = and trachea disease
LEDV = lung = eye = and trachea disease virus
LGRV = loggerhead genital–respiratory herpesvirus
LOCV = loggerhead orocutaneous herpesvirus
PCR = polymerase chain reaction
POTZ = preferred optimal temperature zone
TeHV = testudinid herpesvirus
Suggested Reading
1 Gandar F, Wilkie GS, Gatherer D, et al. The genome of a tortoise herpesvirus (testudinid herpesvirus 3) has a novel structure and contains a large region that is not required for replication in vitro or virulence in vivo. J Virol 2015;89(22):11438–11456.
2 Marschang RE. Virology. In: Divers SJ, Stahl SJ, eds. Mader’s Reptile and Amphibian Medicine and Surgery. St. Louis, MO: Elsevier; 2019:247–269.
3 Marschang RE. Viruses infecting reptiles. Viruses 2011;3:2087–2126.
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