El Niño may accelerate rabies spread among marine mammals and beyond in southern Africa

Scientists warn that climate change-related El Niño could facilitate the unprecedented spread of rabies from Cape fur seals in southern Africa to other regions, posing new global risks.

Scientists are warning that El Niño could help push rabies beyond its current foothold in Cape fur seals in southern Africa, after the World Organisation for Animal Health said the virus had been detected in a sustained way among the species.

WOAH reported in July 2026 that more than 100 cases had been confirmed in South Africa and Namibia since 2024, following what genetic analysis suggests was a single spillover from a dog-related rabies variant carried by black-backed jackals. The seals then began transmitting the virus to one another, an unusual shift in rabies ecology and, according to WOAH, an unprecedented one for marine mammals.

The first known cases emerged in South Africa in 2024, when dead or euthanised Cape fur seals tested positive along the west and south coasts. Since then, authorities have recorded aggressive and disorientated behaviour, including attacks on people, other animals and objects. WOAH says there have been 145 potential human exposures, although no infections were ultimately confirmed.

Researchers cited by The Telegraph said warmer waters associated with El Niño could alter seal migrations, carrying infected animals north in search of food and then back into other subantarctic populations. That raises concern for closely related seal species in South America, New Zealand and Antarctica.

Rabies remains almost uniformly fatal once symptoms appear, and kills about 60,000 people a year worldwide, mostly through dog bites in Asia and Africa.