Without floods, a quarter fewer Africans in this study would have mental health problems - Bhekisisa

- Living through a flood led to mental health issues in about a quarter of people, a new study across four African countries shows.

- The logic then goes that if people can be protected against experiencing the trauma of a flood, their mental health will be better too.

- With extreme rainfall and storms set to hit more often and become more intense with continued global warming, climate change can impact people’s health in ways not recognised — and leave scars long after the disaster.

- What could findings about the mental health effects of floods mean for health policy in Africa? We dive into the data.

In today’s newsletter, Linda Pretorius tells us how floods drive up mental illness in Africa. Sign up for our newsletter today.

In 2024, roughly four in every 10 disasters were because of water overflowing land that is normally dry.

But keeping your head above water when a flood hits is about more than just staying safe in the moment; it’s also about not drowning in feelings of despair, fear or impending dread afterwards.

Studies show that living through a flood can leave psychological scars that last for years — especially if people are poor or have little social support.

Yet the mental health effects of natural disasters such as floods are mostly unknown in Africa — despite half of the continent’s 54 countries having had extreme rainfall in 2024.

Climate models show that extreme rainfall will likely hit more often as the Earth’s air keeps on warming. (In 2025, the global air temperature was about 1.4°C higher than what it was 150 years ago, before we people started burning lots of fossil fuels.) Combine this threat with poor infrastructure like roads, housing, sanitation and healthcare, and limited ability to rebuild when disaster does hit, it’s like a perfect storm brewing — with people’s mental wellbeing as the collateral damage.

This is why a new study looked into how floods affect people’s mental wellbeing in four countries in Africa — Burkina Faso, Kenya, Mozambique and South Africa.

The results are striking: across the four study sites combined, floods led to mental health issues in about a quarter of people who took part in the study. In other words: if the flood had not happened, 25% fewer people would have had mental health problems.

What do the results mean for countries where public health systems are already under pressure and communities have little means to bounce back after a disaster, especially when extreme weather is no longer a rare event?

We jump in at the deep end to wade through the data.

A snapshot of a continent

The research team worked in four countries across West, East and Southern Africa to study the link between flooding and mental wellbeing and “looking at both shared patterns and differences”, explains Ahri epidemiologist Collins Iwuji, the project’s lead researcher. “Although our findings do not represent Africa as a whole, they broaden the evidence on flooding and mental health across these regions.”

The study included a total of 5 336 participants, with a sample of between about 1 000 and 1 600 in each country, with at least as many people having experienced a flood as those who didn’t. The study sites spanned urban and rural areas and included a spread of household sizes and employment and education levels, giving a good mix of socioeconomic conditions.

High waters, low feelings

Across the sample as a whole, signs of mental health problems were more common among people who had lived through a flood than among those who had not.

When looking at data from all four countries combined, one in 12 people who had been in a flood showed signs of serious anxiety, and one in eight had symptoms pointing to depression. One in five flood survivors’ mental state looked like that of someone with post-traumatic stress disorder, a condition in which you feel like you repeatedly relive a terrifying event in some way, often with severe anxiety to boot.

The same trend held in South Africa, but the proportion of flood survivors experiencing mental health problems was more than twice as high.

The findings show that extreme weather events like a flood add another layer of stress to people’s lives when they already live in poverty or without good social support. “When a disaster hits, people suffer because it adds to the hardship they’re facing every day,” says Vasco Cumbe, a psychiatry expert on the research team and based in the Sofala province where the Mozambican part of the study was done.

But people’s distress compounds, he says. In communities like the ones included in the study, a next storm often hits before people can fully recover from the previous one. When the ability to build back livelihoods and infrastructure like houses, roads and clinics is already poor, an additional shock can push people closer to developing mental health problems that mess with everyday life.

In the aftermath of a flood, people usually get help with basic needs like food, water and clothes, says Cumbe, but mental health issues are often not considered. Not paying attention to the effect of weather disasters on people’s mental state is “a gap”, not only in response but also in preparedness, he says.

Fewer floods, better mental health

If people had not been exposed to a flood, 25% fewer people would have had mental health issues, the study shows. In South Africa, that portion was closer to a third.

But with science showing that heavy rain and storms will likely hit more often and become more intense, how can people be protected against the effects of floods?

By limiting their exposure, says Iwuji. The immediate fix is to deal with the situation we already have, he says. For example, if people are warned about the chance of a flood early enough, they can prepare for it or choose to move out of the area during that time. Simple maintenance can also help, like keeping drains clear so that water can run away rather than overwhelm buildings and roads.

The longer game, though, is to curb further global warming. Warm air holds more moisture than cool air, which means that at the 2°C increase set as the upper limit of the Paris Agreement, storms and rainfall could become even heavier than they already are.

The Paris Agreement is a deal reached by nearly 200 countries in 2015 to fight climate change by reducing the pollution that heats up the planet.

Hitting the carbon emission targets agreed to under the Paris Agreement is no longer a theoretical ideal. Building resilient health systems that can cope with the effects of climate change will be formally on the agenda for the first time at COP31 in Turkey in November.

COP is a yearly United Nations meeting where countries from around the world discuss and agree on ways to slow down climate change and protect people from its effects.

‘I feel very scared’

Signs pointing to PTSD were the most common mental health issue among flood survivors in all four countries. However, the amount by which the levels increased was different.

For example, in the Mozambican sample, PTSD symptoms were seen in less than 1% of people who had not experienced a flood, but it was 55 times more common in those who had lived through a flood.

In Kenya, though, just over four in 10 people who had lived through a flood showed signs of PTSD, compared with three in 10 people who had not been exposed to the trauma of flooding. Although this is about four times more than in the group from Mozambique, the comparative in-country change is less.

Someone with PTSD is hyper vigilant, explains Cumbe. “They never relax, they’re always waiting for the danger to hit again, even though they seem to carry on with their lives.” But always expecting danger means someone lives in a constant state of fear and it becomes hard to bounce back.

With only about two specialised mental health workers for every 100 000 people in Africa, getting help to deal with a terrifying event like a flood is almost impossible for many. In this way, “what starts as a psychological condition can trigger a physical illness later”, explains Cumbe, putting even more pressure on health systems that are already overstretched in many countries.

Young lives matter

The trauma of a flood seems to hit young people hard, the data shows. They had more anxiety than other age groups and higher levels of PTSD, even though the baseline levels in the control groups — that is, people who had not experienced a flood — were similar to that in older people.

Today, mental health disorders are the leading cause of disability, analyses show — even more so than heart disease or cancer. “People in this age group are just coming into their productive years,” says Iwuji, “so if mental health problems start at a young age and continue for the rest of their lives, you can imagine the economic impact that would have on the society.”

Yet the psychological fallout of a weather disaster is often overlooked in planning for emergency response, explains Cumbe. “People think it’s not important to raise mental health issues [as a concern]. We shelter people, we give food, we give water. But we also need to pay attention to the psychological side.”

If we don’t, we run the risk of pushing yet another generation into poverty, instead of lifting them out of dire circumstances, says Iwuji. “Climate change is a threat multiplier.”