Syndicate content

COVER STORY OF NOVEMBER JOURNAL OF VIROLOGY: Lethal Herpes Virus of Tortoises Has Newly-Discovered Seventh Distinct Herpes Genome Structure; Potential Vaccine Being Worked On

An inspired intuition of Frédéric Gandar, a Ph.D. student at the University of Liege in Belgium, and of his thesis supervisor Alain Vanderplasschen, Ph.D., to focus on a research topic that has rarely been explored in the scientific world, has paid major dividends. The study of Testudinid herpes virus 3 (TeHV-3), a herpes virus causing high mortality rates in several protected species of tortoises (including Hermann’s tortoise--image), has resulted in several significant discoveries and has been published as the cover article of the November 2015 issue of the prestigious Journal of Virology (JVI). This JVI cover article is titled “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.” Up to the present, the approximately 250 herpes viruses that have been studied – these are found in oysters, as well as in humans – have been divided into six distinct genomic structures. But when Gandar and Dr. Vanderplasschen analyzed Testudinid herpes virus 3, the could not believe their eyes. This virus had an entirely new herpes virus genome structure. This would be the seventh known. The researchers are currently working on a vaccine against this disease that is decimating tortoise species, many of which are endangered. Dr. Vanderplasschen, an immunology and vaccinology researcher at the Faculty of Veterinary Medicine of the University of Liege, admits that nobody in industry would be likely to invest in this research. The reality is that the death of tortoises is not likely to be a source of concern for many people. This subject area also does not seem financially interesting to pharmaceutical companies, so they are not likely to be interested in investing. Fortunately for Gandar, Dr. Vanderplasschen is not an industrialist. Even though there was little likelihood of an economic dividend for his department, he invested in the project in collaboration with Professor Didier Marlier, Head of the Exotic Pets Clinic at the University of Liege, and Professor Marianne Diez, Head of the Nutrition Department, at the University of Liege. Now, after five years of work, the intuition-based investment has proved prescient; the researchers hope to perfect a vaccine that will be capable of immunizing tortoises against the plague that is killing them in such great numbers.

If a group of young tortoises comes into contact with Testudinid herpes virus 3 (TeHV-3), the result will be fatal for 80% to 100% of them.

At first, there will be no visible signs to show that the tortoieses are infected. After an incubation period of approximately twenty days, the first symptoms will appear: nasal discharge, weakness, and white spots in the mouth.

Secondary infections will then appear. Then, the nervous system is affected, and this prevents tortoises from eating and moving around.

Finally, the infection affects all the organs, the spleen, the kidneys, and the brain. Death is virtually inevitable after approximately ten days.

Those tortoises that survive the infection become “asymptomatic carriers.” Without any visible warning, the virus will be carried by them all their lives and will spread to other tortoises they meet.

[Press release] [Journal of Virology Cover Article abstract]