I didn’t know it was native to African Elephants! That explains why they respond better to it than Asian Elephants!
North American Asian and African Elephant Populations: Discussion and Speculation
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I didn’t know it was native to African Elephants! That explains why they respond better to it than Asian Elephants!
My bad, thanks for the correction. Do you happen to know if deaths tend to be caused by the opposite species' strain or is it their own strain? I think I heard at one point Asians were very prone to catching it from Africans and it tended to end up killing them. Which resulted in my earlier post I expect.
That is an excellent question. I was actually going to include exactly what you were asking in my original post, as I’ve heard the same thing anecdotally, but I don’t know if I’ve ever seen a concrete source for that one beyond just word-of-mouth, so I decided not to, lol.
Not much is known about the virus as of yet.
It is widely believed though, that the virus is present in all elephants, and sort of laying dormant if you wish. It's then passed on from the adult cows to calves, apparently during periods of stress within the herd.
The virus has also been known to pass from one species to the other; although there's hasn't been enough research into this yet, regarding it giving a higher mortality rate.
Although on that note, each herd does have it's specific strain of the virus, so it's quite possible that when receiving the virus from an unrelated female, this may trigger a higher mortality rate. Although, again, this is still not confirmed.
I had assumed/knew most of this.
That’s my understanding also. But how did the elephants in Asia get it? Are the Africans imported into that region?
i believe there are at least two strains of EEHV. The African one is more of a killer to Asians as the Asians are more resistant to the native one.
I can be wrong and that’s ok. I am still reading and learning as a supporter of elephant conservation and health.
All elephants have the virus (both African and Asians). Origin wise, i'm not entirely sure we'll ever know how it started. It's all up to assumption. EEHV is believed to have always been present in elephant populations, going all the way back to the Wooly mammoth.
I'm not aware of any Africans being imported to Asia, aside from in zoos/sanctuaries of course.
There are in fact, 14 identified strains of EEHV. It would make sense that the strains carried by Africans would be more deadly to Asians as the Asians have not been exposed to those strains in a very very long time, so wouldn't have the antibodies to fight the virus. They usually receive those antibodies from their mother, and hence, are rather immune to her and her family's strain. In captivity, when they have unrelated females together, they can all have different strains of the virus. So the calf may be protected from their own mother's strain but not the other females, if that makes sense.
To clear up a few misunderstandings: there are EEHV strains that are native to asian elephants and there are different EEHV strains that are native to african elephants. These strains evolved together with the elephants for hundreds of thousands of years (or more).
The strains that kill so many young asian elephants are EEVH1A and EEHV1B, and both occur naturally in asian elephants both in zoos and in the wild, but never in african elephants.
Cross-infection of an asian elephant with an EEHV strain native in african elephants (and the other way around) has indeed been observed in zoos, but very rarely. That is not the cause of death of all those young asian elephants.
If transfers increase the risk of EEHV deaths has acutally been the subject of intense research. The answer is very clearly no. The evidence is very clear now: asian elephant calves are born with high antibody titer against EEHV which protects them against deaths in the first 2 years of life. To keep the antibody titer high after that time, they need exposure to the virus while the antibodies are still high. If that doesnt happen, antibodies decrease and the calves are at a very high risk of death when coming in contact with the virus. It seems the main problem in zoos is that groups are too small so that the virus is shedded not often enough when calves are young. The holders with the bigger elephant herds have rarely problems with EEHV (Emmen, Hannover, Cologne in Europe, Ringling and African Lion Safari in Canada).
The strains that kill so many young asian elephants are EEVH1A and EEHV1B, and both occur naturally in asian elephants both in zoos and in the wild, but never in african elephants.
Cross-infection of an asian elephant with an EEHV strain native in african elephants (and the other way around) has indeed been observed in zoos, but very rarely. That is not the cause of death of all those young asian elephants.
If transfers increase the risk of EEHV deaths has acutally been the subject of intense research. The answer is very clearly no. The evidence is very clear now: asian elephant calves are born with high antibody titer against EEHV which protects them against deaths in the first 2 years of life. To keep the antibody titer high after that time, they need exposure to the virus while the antibodies are still high. If that doesnt happen, antibodies decrease and the calves are at a very high risk of death when coming in contact with the virus. It seems the main problem in zoos is that groups are too small so that the virus is shedded not often enough when calves are young. The holders with the bigger elephant herds have rarely problems with EEHV (Emmen, Hannover, Cologne in Europe, Ringling and African Lion Safari in Canada).
This is further supported by studies comparing the antibody levels of young elephants in European zoos with their age matched peers at the Pinnawala Orphanage (home to over 90 elephants) - with the larger herd size at the orphanage increasing their contact with EEHV shedding elephants (and increasing their antibodies).
Young elephants in a large herd maintain high levels of elephant endotheliotropic herpesvirus-specific antibodies and do not succumb to fatal haemorrhagic disease - PubMed
Elephantelephant
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I totally agree. Zoos should focus on breeding larger groups of elephants in the future, although I recognize that it is EEHV that makes these groups difficult to build.
Note - When it comes to large groups, Pairi Daiza still needs to be mentioned. The virus does not occur there at all, and plasma from their elephants has already saved several infected calves in other zoos.
I believe it's related to the mothers providing their calves with antibodies via their milk. Once the calf is weaned, that's when they can begin to become more susceptible to the virus, as they're no longer receiving the antibodies they need.
Yes you already said this five posts upthread. I assume Yassa also saw it since he responded to all of our earlier discussion to clear things up for us. You really don't need to keep repeating yourself just because somebody disagreed or didn't mention your information.
It was more of an extension/elaboration to what I had previously said, but okay.
That's very intriguing.
But are the antibodies only to a specific strain or multiple? I was under the assumption that the antibodies only protected the calf to the strain the mother had.
Antibodies are specific to a strain of EEHV and dont protect against infection against another strain; however, they do likely/ usually protect against severe disease/ death from another strain. And dont forget that the mother is often infected with more then one strain.
One thing that really concerns me regarding Mkhayas case is that her 2 older brothers and 1 older sister never caught EEHV. It makes me wonder anyway why she caught it and her older siblings did not.
It’s nothing to be concerned about. Her two male siblings are both living at other facilities now, and her older sister is in her mid teens. All of them are out of the prime age range for herpes infection, and likely carry sufficient antibody amounts to remain unaffected by the virus.