Scientists in South Africa have discovered an outbreak of rabies in seals, marking the first known instance of the virus spreading among sea mammals. At least 24 Cape fur seals were found dead or euthanized along South Africa's west and south coast, all testing positive for rabies. Rabies, a fatal virus that affects mammals and can be transmitted to humans, spreads through saliva, primarily via bites or grooming.
While rabies is commonly found in terrestrial animals like raccoons and domestic dogs, its emergence in marine mammals is unprecedented. The only previous case involved a ringed seal in Norway in the 1980s, likely infected by a rabid arctic fox.
The outbreak in South Africa was first detected in June after a dog was bitten by a seal in Cape Town. Subsequent tests on seal carcasses collected since 2021 revealed more positive cases, indicating a wider spread of the virus among seal populations.
Researchers suspect that jackals in Namibia initially transmitted rabies to seals, as genetic analysis showed a match between the virus in seals and black-backed jackals. The virus is now circulating within the seal population through biting.
Authorities in South Africa are working to understand the transmission dynamics and contain the outbreak. Cape Town has issued warnings to residents, especially those living near seal colonies. Reports of aggressive seals and attacks on humans in recent years had puzzled officials, but no human rabies cases have been reported.
Efforts are underway to vaccinate seals in popular harbors, although the challenge lies in vaccinating a large number of seals that migrate along a vast coastline. The effectiveness of the vaccine in seals remains uncertain, but experts are optimistic about its potential.
International collaboration is ongoing to address the outbreak, with concerns raised about the potential spread to other seal species worldwide. While the long-term implications are still unclear, experts are closely monitoring the situation to prevent further transmission of rabies among marine mammals.
Overall, the emergence of rabies in seals presents a unique challenge that requires further research and coordinated efforts to protect both seal populations and human communities.
