A female elephant died from the herpes virus at Zoo Zurich on Saturday making it the third such fatality in a month. 

Ruwani, a five-year-old elephant, showed no signs of illness until Friday, the zoo said on Saturday. In the last few days, her viral load had fluctuated between high and low values. In order to prevent the disease from spreading, the zoo started treatment with antiviral drugs at an early stage but could not prevent her death.
On June 28, a two-year-old male elephant called Umesh had already died of the virus, and just a fortnight ago, eight-year-old female Omysha followed suit.

Young animals at risk

According to the zoo, the elephant herpes virus itself does not pose an acute danger to pachyderms. However, if it multiplies strongly in the body, it can trigger a disease called elephant endotheliotrophic herpes virus (EEHV). This often leads to death, especially in young elephants, when the protection offered by their mother's antibodies diminishes and they have not yet produced their own. 

The risk of EEHV is thought to be low for the remaining five elephants, as the youngest is 17 years old. However, the remaining animals will continue to be medically monitored.

EEHV has a mortality rate of around 85% and is believed be responsible for around half of all deaths of elephants in European and American zoos since the 1980s. In February, the Chester Zoo with scientists from the University of Surrey began the first trialsExternal link to develop a vaccine for the disease.
 

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