Ulf Tubessing, [11 May 2025 at 08:36:09]: Good morning! I have, over the past few days been contacted by multiple farmers within a radius of 40 km who reported significant mortalities amongst their giraffe (at this stage around 25-30). Most are found dead but yesterday a client called me reporting 5 mortalities in a 1000 ha camp. They have observed 4 before they died but only noticed severe lethargy, little response to the proximity of people, drooling and then death. This is an area that had very good rain and there is definitely no food deficiency. Most carcasses were too decomposed for the farmers to want to do a PM. None reported blood from body orifices etc., so not sure about anthrax. I have seen a single case with rabies in giraffe years ago but never an outbreak. Any other DDx you can think of that could cause this? What about botulism?? Ilana van Wyk, [11 May 2025 at 08:49:59]: Clostridium novyi? HO Reuter, [11 May 2025 at 09:09:26]: Good morning, Ulf, Are these north of Okahandja? I have had a report of 6 giraffe mortalities on a farm there. (Probably included in your number of 25-30?). Most were already decomposed to a degree, when they found the carcasses. I asked them to call if they see sick, or fresh dead animals. No other species were involved. With an anthrax outbreak, I would expect other species to be infected, but on this farm, there were also no blood from any orifices. Robert Campbell, [11 May 2025 at 09:14:32]: What do the water sources look like? Hendrik Hansen, [11 May 2025 at 10:06:23]: Ulf, I have seen Cl. novyi and Cl. sordelli produce "acute death outbreaks". These would be high up on my DD list. Those were also more in years with good rainfall. HO Reuter, [11 May 2025 at 10:13:53]: How do you test / confirm diagnosis, Hendrik? Hendrik Hansen, [11 May 2025 at 17:02:04]: Send 6 muscle impression smears for fluorescence and Clostridium identification Maaike de Schepper, [11 May 2025 at 10:44:49]: I also had 1 mortality north of Okahandja. On post-mortem examination the small intestines were reddish inflamed and empty, the lungs looked bad, the rumen was full, but the heart, spleen, liver looked normal. No other mortalities were seen at that farm. Ulf Tubessing, [11 May 2025 at 11:15:59]: Thanks for the feedback! HO you are correct, your farm was included. I have not seen any fresh carcasses either. Gernot Redeker, [11 May 2025 at 14:41:28]: Hi. These may be the same farms as HO and Ulf, but I know of 3 farms north of Okahandja with 15 deaths. I found one yesterday from a helicopter, but it had unfortunately been dead for 4-5 days and was completely decomposed. I tested one 2 weeks ago for rabies, which was negative. I also have not seen a fresh one yet. I have also had many farmers call me about springbok. The numbers varied between 1 - 2 deaths per day and 1 per month over a huge area, from Windhoek to Otavi. Roy Bengis, [11 May 2025 at 17:09:34]: Much depends on whether this is a gastrointestinal Clostridial toxaemia, or a Clostridial myositis. Age, class and gender of carcasses may give us an answer. Louis Greeff, [11 May 2025 at 20:28:16]: Ulf, I am busy investigating the role of three-day stiff-sickness (bovine ephemeral fever) and Bluetongue in the epidemiology of this phenomenon. I personally think they go down because of a virus affecting their muscles, causing them to go down. Then they struggle to get up and that causes secondary muscle damage which leads to clostridial infections. In our area, a lot of farmers vaccinate against Clostridia but still lose giraffe due to this. If you find a fresh carcass or one that is still alive, draw blood and test for the Orbiviruses also. I found two that went down and were still alive to be positive on antibody titres for three-day stiff-sickness. They were not able to test for antigen. I need to wait for another one to test again. Where else except OP can you test for antibodies and antigen for this type of viruses? OP is not very helpful in this regard. Danie Odendaal, [11 May 2025 at 21:29:03]: Design Biologix do test for both, but as part of research and not as a commercial service. For three-day stiff-sickness you will only find virus in the early febrile phase. Doing research on both in the development and improvement of vaccines. Ulf Tubessing, [11 May 2025 at 21:48:10]: Great input thanks Louis and Danie HO Reuter, [12 May 2025 at 22:03:11]: I had no idea what causes these giraffe mortalities, but three-day stiff-sickness followed by Clostridial infection (eg sponssiekte / Cl. chauvoei) makes sense following our good rainy season. I think you may be right (again), Louis. Thanks for this input. Jacoba Dongo, [13 May 2025 at 08:24:58]: Area? Jacques ODell, [13 May 2025 at 08:52:22]: Has redgut/rooiderm (Clostridium perfringens Type A) and/or pulpy kidney disease (Clostridium perfringens Type D) been ruled out? The sudden change in browse quality and quantity will play a huge role. I don’t think what you are seeing now is the same as what we see in the Limpopo bushveld where myositic Clostridia is the killer. HO Reuter, [13 May 2025 at 15:24:09]: Re: Giraffe mortalities in central north Namibia: at least some of these farms had a severe hailstorm towards the end of their rainy season and seems most giraffe mortalities occurred after this. Is tannin poisoning likely after leaf damage from hail? Ulf Tubessing, [13 May 2025 at 15:54:26]: I know of one PM done that a suspicion of rooiderm was present, but we need lots more samples to know we are on the right track It's unlikely that tannin poisoning is the culprit, since the mortality reports stretch from SW Etosha region all the way to the eastern parts up to the red line, and towards Okahandja. All giraffe had similar symptoms - lethargy, some drooling, not scared of people, seem to be ataxic, standing in the bushes. Some animals were observed as sick or abnormal for 2-3 up to 4 days before found dead. I received 2 reports of people thinking that the giraffe were blind - the giraffe were walking into objects and stumbling around. Jacoba Dongo, [13 May 2025 at 17:06:17]: Zoonotic Arbo and Respiratory Virus Program | University of Pretoria https://www.up.ac.za/zoonotic-arbo-and-respiratory-virus-program What about other arboviruses? West Nile virus was isolated from a giraffe. Ulf Tubessing, [14 May 2025 at 01:19:32]: Jacoba, I am biting at the bits to get to one of them in time to take fresh samples. Thanks for your input! Nele Sabbe, [14 May 2025 at 09:15:14]: As far as I was told 2 weeks ago: the project doesn't exist anymore...
