An outbreak of anthrax in endangered Rothschild’s giraffes in Mwea National Reserve, Kenya

One disease outbreak killed a quarter of a reserve's giraffes in three months. Between May and July 2011, eleven Rothschild's giraffe carcasses were found in Kenya's Mwea National Reserve, where the population had been estimated at forty-four. Protection from habitat loss did not protect this small population from a sudden infectious threat.

Titus Kaitho, David Ndeereh and Bernard Ngoru investigated the deaths and reported the emergency response. Laboratory examination confirmed anthrax. The team burned the carcasses to limit environmental contamination and used darts to vaccinate surviving giraffes. Reaching them was not straightforward: some disappeared into dense vegetation or difficult terrain, and fallen darts made previously treated individuals harder to recognise.

Twenty of the thirty-three surviving giraffes were vaccinated. No further anthrax-related giraffe deaths were reported over the following two years. Because vaccination, carcass disposal and other controls happened together, this field report cannot separate their individual effects. Nor did the absence of new deaths show that the environment was free of spores. What it records is a successful interruption of an emergency—and how quickly disease can remove a substantial share of a small giraffe population, even inside a protected reserve.