From Bats to Humans: How Nipah Continues to Challenge Public Health

The recent Nipah virus outbreak in Kerala, southern India, has renewed global attention to the dangers of emerging zoonotic diseases, pathogens that jump from animals to humans. With a case fatality rate as high as 75%, Nipah is one of the world’s most lethal viruses, yet it remains relatively unknown across much of Africa. The current situation in India is a warning that the conditions enabling spillover, such as deforestation, wildlife-human interaction, weak surveillance, and climate change, are not unique to Asia alone.

What is the Nipah Virus?

Nipah virus (NiV) is a highly infectious zoonotic virus in the Paramyxoviridae family. Fruit bats of the Pteropodidae family, which are also common in sub-Saharan Africa, are natural carriers. The virus can spread from these bats directly to humans or through intermediate hosts like pigs and horses. Human-to-human transmission is also possible through respiratory droplets, contaminated food, or contact with infected bodily fluids.

The symptoms range from mild flu-like signs to severe acute respiratory infection and fatal encephalitis. In many cases, patients progress rapidly from symptoms to coma within days. There is no specific treatment or licensed vaccine for NiV yet, although promising trials are underway.

The Situation in Kerala

Since 2018, Kerala has recorded ten confirmed Nipah virus spillovers. The most recent in July 2025 involved a 52-year-old man and marks the fourth case this year alone. All cases occurred within a 50km radius, pointing to a high concentration of infected fruit bats in the area. Authorities in Kerala have responded with aggressive contact tracing, house quarantines, syndromic surveillance, and early treatment using broad-spectrum antivirals such as Ribavirin and Remdesivir. These efforts have helped limit the spread, but the region remains on alert.

One of the emerging concerns is the possibility of airborne transmission. While still under investigation, researchers suggest that the virus could travel through the air over short distances, further complicating containment efforts.

Why This Matters for Africa

Africa is not immune, as fruit bats that serve as reservoirs for Nipah exist across sub-Saharan Africa, including in Ghana. Although no human cases have been confirmed on the continent, the ecological and environmental conditions that promote zoonotic spillover are very present: rapid urban expansion, deforestation, intensive farming, weak surveillance systems, and poor integration between human and veterinary public health systems.

The COVID-19 pandemic highlighted the costs of underestimating zoonotic threats. Although African countries responded quickly to COVID-19 with public health measures, many still struggled due to weak health systems and reliance on external aid. Vaccine access was delayed, revealing the need for local production and stronger infrastructure. Some nations are still recovering, highlighting long-standing gaps in preparedness and health system resilience.

Nipah, with a much higher fatality rate and no treatment, could be far worse. Moreover, many African countries still lack the lab capacity and surveillance systems required to quickly identify and respond to a Nipah outbreak.

There is therefore a need to urgently adopt a One Health approach, which means strengthening coordination between human, animal, and environmental health sectors to detect and respond to outbreaks before they escalate.

Further, as climate change alters ecosystems and brings wildlife and humans into closer contact, zoonotic outbreaks will become more frequent. Rising temperatures and habitat shifts may also affect viral load and host behaviors, potentially increasing the chances of spillover.

The Nipah virus is a reminder that global health threats are interconnected and increasingly borderless. What is unfolding in Kerala, India, should not be considered a distant problem but a call to action for countries in the tropics. Now is the time to build robust, multi-sectoral systems that can detect and contain high-threat pathogens before they emerge.