What is Anthrax? The deadly bacteria that killed over 50 hippos in Africa's Virunga National Park

At least 50 hippopotamuses and other large wildlife have died from anthrax poisoning in eastern Congo’s Virunga National Park, with carcasses seen floating down a river that eventually empties into one of Africa’s Great Lakes.
The deaths, confirmed to be caused by anthrax, were announced by Virunga Park director Emmanuel De Merode on Tuesday. “Buffalo have been killed too,” De Merode stated, although the precise trigger of the outbreak remains uncertain.
Disturbing visuals released by the park reveal hippo bodies lying still—some belly-up—in the Ishasha River, others trapped in the foliage along its muddy shoreline.
The incident marks a heavy blow to Virunga’s conservation efforts. Once home to over 20,000 hippos, the park saw its population plummet to mere hundreds by 2006 due to war and poaching. Years of restoration brought the numbers back up to around 1,200, but this latest outbreak could reverse those gains.

Park rangers first realized something was wrong when dead animals began appearing roughly five days ago in the Ishasha River, which forms part of the border between the Democratic Republic of Congo and Uganda. The area is also known to be under the control of rebel groups, further complicating access and response efforts.
In light of the outbreak, the Congolese Institute for Nature Conservation issued a public warning on Tuesday, urging local communities to stay away from wildlife and to boil water from nearby sources before drinking.
De Merode said a response team is on the ground, but their efforts to remove and bury the carcasses are being hampered by limited resources. “It’s difficult due to lack of access and logistics,” he told Reuters. “We have the means to limit the spread (of the disease) by…burying them with caustic soda.”
The Ishasha River flows north into Lake Edward, where more bodies have since been spotted.

“There are more than 25 hippopotamus bodies floating in the waters of the lake, from Kagezi to Nyakakoma,” civil society leader Thomas Kambale in Nyakakoma told Reuters.
Anthrax, a severe illness most commonly caused by soil-dwelling bacteria, can infect wild animals when they breathe in spores present in contaminated dirt, plants, or water. Let us understand more about it.

Anthrax is a zoonotic disease caused by the bacterium Bacillus anthracis, which occurs naturally in soil worldwide. According to the , it primarily affects livestock and wild animals—including cattle, sheep, goats, antelope, and deer—which can become infected by inhaling, ingesting, or drinking spores from contaminated soil, plants, or water.

As described in a published in the National Library of Medicine, Bacillus anthracis is an aerobic or facultatively anaerobic, capsulated bacterium that produces spores when exposed to the environment through body fluids of a carcass. These spores can survive for long periods, making the disease highly resilient in the environment. In animals, ingestion is the most common route of infection—particularly through contaminated feed, forage, or water. Any wounds in the digestive tract’s mucosal lining can allow the bacilli to enter the system. Inhalation of contaminated dust is less common in animals but still considered a possible route.
Humans can contract anthrax through contact with infected animals or contaminated animal products. Spores can enter the body via inhalation, ingestion, or cuts and abrasions in the skin. Occupational exposure—especially among workers handling hair, wool, hides, or skins—has been a known risk factor for both inhalation and cutaneous anthrax.