The World Health Organisation (WHO) has identified six climate and health interventions that could prevent 1.6 million deaths annually while generating $9.3 trillion in combined economic and fiscal benefits worldwide.
The measures include heat-health warning systems, climate-resilient drinking water services, improved sanitation and hygiene, cleaner household energy, and efficient fossil fuel pricing policies.
According to a new WHO report titled Global Benefits and Costs of Prioritised Actions on Climate Change and Health, implementing the interventions globally could also prevent 16.7 billion tonnes of carbon dioxide emissions annually.
The report, released ahead of the 31st Conference of the Parties (COP31), provides an assessment of the economic and fiscal benefits of implementing six recommended climate and health interventions on a large scale.
WHO Director-General, Dr Tedros Adhanom Ghebreyesus, said the climate crisis was also a health crisis, but stressed that many of its consequences could be prevented through existing interventions.
He said expanding affordable and proven measures could save millions of lives, particularly in countries most vulnerable to climate change.
Tedros emphasised that protecting public health should remain central to international climate negotiations.
The report estimated that implementing the six interventions could prevent one in every 40 deaths globally, based on modelled projections.
It also projected that the resulting reduction in emissions would be equivalent to 31 per cent of global annual greenhouse gas emissions, excluding land use, land-use change and forestry.
On the financial benefits, WHO said every dollar invested in five of the six measures could generate an estimated $24 in returns, with low- and middle-income countries expected to benefit significantly.
Heat-health warning systems were identified as particularly cost-effective, with an estimated return of $835 for every dollar invested.
According to the report, these systems can use existing infrastructure to anticipate extreme heat conditions and enable governments and communities to take preventive action against heat-related illnesses and deaths.
However, efficient fossil fuel pricing policies, including the removal of inefficient subsidies and appropriate taxation of fossil fuels, were projected to deliver the largest overall benefits.
WHO estimated that implementing these policies could prevent 1.2 million deaths annually, generate $3 trillion in economic welfare benefits and provide an additional $5.4 trillion in fiscal gains.
Other recommended interventions include expanding access to climate-resilient drinking water, basic sanitation facilities, hygiene and handwashing services, as well as cleaner household fuels and technologies for cooking and heating.
The organisation said these measures would reduce exposure to climate-related health risks while addressing wider public health challenges, particularly in vulnerable communities where inadequate infrastructure and limited access to essential services worsen the effects of climate shocks.
WHO also stressed that achieving the projected benefits would require coordinated action beyond the health sector, involving government agencies responsible for water, sanitation, energy and environmental policies.
With countries experiencing increasingly severe climate shocks in 2026, the organisation called on governments, development partners and financial institutions to accelerate investments in the recommended interventions.
It maintained that protecting public health should be treated as a central component of climate action rather than a separate development priority.
According to WHO, the measures offer governments an opportunity to save lives, reduce emissions and strengthen their economies simultaneously.
