Discovery of unidentified bacteria in Zimbabwean elephants leads to their mysterious deaths

Scientists have discovered a new type of bacterium in the bodies of six African Savannah elephants that died under mysterious circumstances in Zimbabwe. The bacterium, called Bisgaard taxon 45, is believed to have caused a form of blood poisoning known as septicaemia that led to the deaths of these elephants in 2020. The findings of this study, which involved investigations into the deaths of 356 elephants in neighboring Botswana, have been published in the journal Nature Communications. Conservationists made headlines when they discovered the dead elephants in Botswana's Okavango Panhandle. Some of the elephants had collapsed and died suddenly while walking or running. To understand the cause of these deaths, researchers conducted post-mortem examinations on 15 elephants in North-Western Zimbabwe. Dr. Chris Foggin, a wildlife veterinarian from the Victoria Falls Wildlife Trust, explained that the team had to locate the bodies using a helicopter due to the elephants' large size. Despite the physical challenges, the researchers were able to confirm that 13 of the elephants had septicaemia when they died. Particularly significant was the identification of the new bacterium, Bisgaard taxon 45, in six of the animals. This bacterium had been previously found in swabs taken from tiger or lion bites but had never been associated with septicaemia in African elephants before. Prof Falko Steinbach from the UK's Animal and Plant Health Agency, who was involved in the investigation, suggests that severe drought and a shortage of food in 2020 may have compromised the elephants' health, making them more susceptible to the disease. He explains that certain bacteria, like Bisgaard taxon 45, exist without causing harm, but if an animal's immune system weakens, these bacteria can spread and cause severe disease. The researchers are concerned about the transmission of the bacterium to other elephants due to their highly social nature, which could help explain the high number of deaths. Laura Rosen from Transboundary Epidemiology Analytics expresses worry over these findings, emphasizing the importance of investigating and understanding the deaths of these endangered elephants to ensure the future of the species. Prof Steinbach suggests that further research is needed to understand the connection between this infection and the stress related to extreme weather events such as drought. He hopes that through more studies, interventions, and possibly even a vaccine can be developed to prevent these outbreaks, but acknowledges that extensive investigation is required.