Human health is paying the price of failure to curb global warming, the World Health Organisation warns, urging governments at UN climate talks to cut carbon emissions faster and provide funds to address growing threats.
Those range from lung and heart problems caused by toxic air to deaths in storms and wildfires, and the expansion of dengue, malaria, cholera and other diseases spread by mosquitoes and contaminated water.
At the Madrid climate talks on Tuesday, activists and aid agencies cited a rise in hospital emissions linked to smoke from Australia's recent bushfires.
In southern African countries hit by Cyclone Idai this year, they said, people are struggling to feed their families after fields and homes were destroyed.
"The cost of not taking enough action at the climate summit ... is paid by my lungs and your lungs," said Maria Neira, director of the department of environment, climate change and health at the WHO.
The causes of climate change and air pollution overlap, she added, calling for societies to "decarbonise", including by ditching coal as a source of power and heat, and ending subsidies for the extraction and use of fossil fuels.
According to the WHO, the burning of oil, gas and coal is responsible for two-thirds of the outdoor air pollution that causes about 4 million premature deaths each year.
More intense and longer heatwaves are another growing health problem in many parts of the world.
A study published in the journal Nature on Monday found extreme heat in the US from 1969-1988 caused an increase in deliveries of babies on the day it hit and the day after, with those births up to two weeks premature.
Such early births can potentially harm children's later development, researchers said.
To deal with the rising human and financial health costs of climate change, health services and related institutions need a boost in funding - currently sorely lacking, the WHO said.
On Tuesday, it released a report highlighting how countries are increasingly prioritising dealing with climate change threats to health.
Half of about 100 nations surveyed said they had developed a national strategy or plan to tackle the risks but less than 40 percent had finances in place to even partially implement their plans.
In richer countries, the difficulty lies in securing allocations from national budgets due to competing priorities.
Poorer nations, on the other hand, need international climate finance to help them cope, but are struggling to access it because of a lack of information, capacity and connections.
The WHO plans to help developing countries put together projects to bolster their health systems that can secure backing from international climate funds, he added.
One of the biggest potential sources of finance, the Green Climate Fund, has identified health and wellbeing as a priority area but has yet to approve any projects with that focus.
Things that could be financed might include "smart hospitals" - now being tested in the Caribbean - built to withstand strong winds and floods while also harvesting rainwater and running on solar power.
The mental health impacts of climate change are also under focus.
The effects can range from the trauma of going through disasters to the shock of being made homeless, or young people feeling anxious and frustrated about climate change.