Superbugs + climate change = double trouble. Here’s why.
Superbugs are a big public health issue. So is climate change. Put the two together and the problem becomes even bigger, writes Ida Jooste.
What once was a medical miracle has now become a nightmare At a Bhekisisa webinar, scientists discussed how changing climate conditions are helping the spread of germs, called bacteria, that antibiotics—which one of the experts at the online event called “the eureka of medicine”—can no longer kill.
They’re called superbugs, because they’re near impossible to kill with the medicines we’ve relied on for decades.
It’s a big problem. A study published in The Lancet found that in 2019, such drug-resistant infections killed 1.27 million people worldwide. In roughly the same period, global HIV-related deaths were estimated at around 718 000 a year. In other words, infections caused by bacterial superbugs led to nearly twice as many deaths around the world as HIV.
These germs are all around us, said Luther King Abia, an environmental microbiologist at the University of KwaZulu-Natal, during the webinar. They can cause untreatable or very difficult-to-treat throat, ear, chest (for instance, pneumonia and TB), and skin infections, as well as meningitis and cholera, and sexually transmitted infections such as gonorrhoea, syphilis, and chlamydia, amongst other diseases.
And climate change is making the problem worse.
Why?
Because changing weather patterns and more frequent and severe flooding as a result of it, can make superbugs spread faster and further. We answer 11 questions, to make it easy to understand why.
What are superbugs?
The term “superbugs” is often used to talk about germs like bacteria, viruses or fungi that can withstand drugs designed to kill or stop them from growing. They cause infections that are almost impossible to cure with the medicine we have available. “These germs have become super powerful, because nothing can kill them,” says King.
Where do superbugs come from?
Like all living things, disease-causing bacteria try to protect themselves or fight back against threats—such as antimicrobial drugs. (Bacteria and other germs are called microbes because they are so small that they can only be seen with a microscope or other imaging equipment; antimicrobial means something that works against microbes.)
Over time, some bacteria have changed in ways that let them outsmart the medicines designed to kill them. So, instead of dying out, they multiply. When this happens antimicrobial resistance (AMR) is said to have developed—which gives rise to superbugs.
What causes antimicrobial resistance?
AMR is mostly because of the overuse of antibiotics, a group of antimicrobial drugs used to treat bacterial infections. These medicines became widely used in the mid-1940s when scientists figured out how to make lots of an antibiotic called penicillin in labs. The discovery changed modern medicine, as this antibiotic could kill many types of bacteria that used to cause deadly infections.
The more we use antibiotics, the more chances we give bacteria to find ways to outsmart the medicine.
Bacteria replicate by dividing in two, which means every time a bacterial cell divides, their number doubles. Because their life cycle is so fast, this doubling effect quickly leads to huge numbers of germs developing. If even just a few are able to withstand the antibiotic’s effect and so survive until the next replication cycle, the number of resistant ones can increase very fast.
The more a certain type of germ gets peppered with a specific antibiotic, the bigger the pool of those that aren’t affected by the drugs become, until, eventually, each new copy of that type of germ is able to withstand the medicine.
What does the data say about superbug infections?
“Antimicrobial resistance... is without question one of the most pressing health challenges of our time,” Tedros Ghebreyesus, the World Health Organisation (WHO) director general, told world leaders in 2024.
Data from the WHO’s latest AMR report, published in October, together with a useful fact sheet, shows that nearly one in six bacterial infections worldwide is now resistant to commonly used antibiotics. In Africa, it’s one in five.
It’s a growing problem, and several common bacteria are showing resistance to widely used antibiotics, especially in poorer parts of the world. In fact, “by 2050, drug-resistant infections could have killed 39.1 million people [since 2025]—that’s about eight jumbo jets crashing every single day for 25 years,” explained King. The figure refers to deaths where drug-resistant infections become untreatable or turn routine care into a serious risk, according to a 2021 study published in The Lancet.
Those bacteria that are fast becoming resistant include Escherichia coli, a germ that often causes urinary infections, Klebsiella pneumoniae, a germ that can cause serious pneumonia and infections in newborns and hospital patients, and Acinetobacter baumannii, a type of microbe often found in hospitals, infecting the lungs and making wounds difficult to heal.
Poorer countries are often hard hit by superbug infections. But a report from the WHO and UN Environment Programme shows that many of these countries don’t have lab facilities to test what type of germs causes an infection. Without such tests, doctors often have to guess which type of antibiotic will work. If the guess is wrong, the treatment won’t kill the infection and the WHO warns that any resistant germs already present can then keep multiplying. Too few equipped labs therefore make it easier for drug-resistant infections to spread.
Why does climate change make superbugs spread?
Changes in the normal weather patterns and more frequent floods, heavy storms, heatwaves or droughts are signs of climate change. The fallout of these changes can weaken sanitation systems—whether because of infrastructure being damaged or clean, running water being scarce—which can cause infections to spread easily.
Floods and storms can carry germs from one area to another, making the infections that follow harder to stop.
Some disease-causing microbes in a certain area may already be resistant to medicine, and can spread to more people and places when floods or heavy rain carry dirty water, sewage, and mud further and faster than usual. For instance, a study that looked at antibiotic resistance before and after floods found that floodwaters can carry many, many superbugs into rivers, soils and coastal waters, making it more likely that people come into contact with them.
Droughts too can help germs, including superbugs, spread. When water supplies run low, people struggle to wash their hands or flush toilets properly, which makes it easier for germs to move between people. Because climate change is causing longer periods of drought, these conditions are likely to become more common, increasing the risk that superbugs spread in communities.
How does hotter weather affect superbugs?
Heat helps bacteria grow and adapt faster. For example, a 2025 study found that when soil warms (because of hotter days), bacteria can switch on more genes that can help them withstand drugs. In this way, higher temperatures can help superbugs survive and multiply. Indeed, an analysis published last year showed that hotter weather and heatwaves are linked to more drug-resistant infections around the world.
How do superbugs affect people’s lives?
Drug-resistant germs make common illnesses or injuries—like urinary tract infections, pneumonia, wounds and blood infections—more dangerous. When antibiotics that used to be effective don’t work anymore, infections last longer, are harder to control, and have more time to spread—and doctors have fewer safe treatment options.
This is also bad news for everyday medical procedures like childbirth, surgery and cancer treatment, when antibiotics are important to help stop infections when the body’s immune system is weak. Without effective antibiotics, problems that were once easy to treat can quickly become serious.
According to the South African health department’s latest strategy framework for AMR, patients with superbug infections often have to stay in hospital longer and they have more complications. This is a serious warning, says King. If this trend continues, more people will die from infections doctors can’t treat, hospitals won’t cope and treatment will become more expensive for both public and private patients.
Who is most likely to get very sick from superbug infections?
AMR hits hardest among babies and older people, because their immune systems are weaker. A global analysis, which looked at drug-resistant infections between 1990 and 2021, found that deaths caused by superbugs among people aged 70 and over almost doubled in this time.
Superbug infections also hit the poor hard—even in a wealthy country like America, where a study in Texas found that people living in poorer neighbourhoods were far more likely to have superbug infections than those in wealthier areas. This, the researchers said, suggests that crowding, poor sanitation and less access to healthcare create conditions that make it easier for superbugs to spread. An analysis of studies from many parts of sub-Saharan Africa shows that in poorer communities—where water, toilets and healthcare are limited—drug-resistant infections are common.
Is antimicrobial resistance already a problem in South Africa?
Yes. The clearest example of AMR in South Africa is drug-resistant tuberculosis (TB). When TB no longer responds to the main medicines used to treat it, it’s called multidrug-resistant TB, or MDR-TB. If the bacteria become resistant to even more drugs, including the backup ones, it’s called extensively drug-resistant TB (XDR-TB).
The WHO says many people with drug-resistant TB still aren’t getting the right treatment, and South Africa is one of the 10 countries where this gap is largest. TB treatment is hard enough, and even though some new medicines are easier to take, the stronger drugs used for resistant TB are still much tougher on patients. Treating can take years, the medicines can be toxic, and the side effects are often severe. TB shows, in the most human way, what antimicrobial resistance looks like when it hits home.
What about making new types of antibiotics to stay ahead of the germs?
It’s not that simple. Developing a new antibiotic is slow, expensive and often not profitable for drug companies. Doing this can take more than a decade and cost more than $1 billion—that’s around R16.5 billion over ten years—and even then, bacteria often start finding ways around new medicines within a few years.
Different antibiotics work by attacking different “weak spots” in bacteria, for example, breaking down their cell walls or blocking how they make proteins. But bacteria don’t have endless weak spots, and existing antibiotics already target many of them. So, when new antibiotics come out, they’re often just small variations on older drugs, not truly new weapons. That means bacteria can adapt to them more quickly, especially if the drugs are overused.
We also need to protect the drugs we already have by using them wisely, preventing infections in the first place, and tracking how resistance spreads.
What does the “One Health” idea mean?
Humans, animals and the environment are connected, and germs move freely between them. So when resistance builds in one corner, it doesn’t stay there.
How it works in real life is that people get infections from water, food, soil, animals and other people. Animals also get infections and are often treated with antibiotics. The waste from both people and animals flows into the environment—especially into water systems—where bacteria mix, survive and sometimes become resistant. Those resistant bacteria can then move back into people through drinking water, crops, or direct contact.
Climate change makes these links stronger. An analysis of data from 2000 to 2023 shows that higher temperatures and extreme heat tend to make drug resistance worse. Rainfall also affects resistance, but in different ways depending on the germ.
This shows why AMR plans need to take climate into account.
Hotter weather helps bacteria grow faster. Heavy rains and floods wash waste from farms, households and clinics into rivers and dams, and can spread resistant germs over wide areas. Drought forces people and animals to share limited water sources. As weather patterns change, diseases move into new regions, taking resistance with them.
This is why we can’t fight AMR by focusing on hospitals alone. Slowing resistance also depends on safe water and sanitation, good farming practices, careful antibiotic use in people and animals, and planning for climate pressures. These systems are connected, so the solutions have to be connected too.
This story was produced by the Bhekisisa Centre for Health Journalism.
Ida Jooste is a journalist for the Bhekisisa Centre for Health Journalism.
Africa’s energy paradox: cheap technology, costly finance
Two identical solar plants: one in Spain, one in Kenya. Same panels, similar sun, similar engineering. Yet one produces cheap electricity while the other struggles to deliver affordable power.
The difference is not technology, labour, or resource endowment. It is the cost of capital. Across Sub-Saharan Africa (SSA), electrification and power-sector decarbonisation are often framed as technology or resource challenges.
In reality, they are finance-architecture challenges. Solar and wind costs have fallen dramatically worldwide, but the cost of money required to build, connect, and operate electricity systems in SSA remains persistently high. This financing premium affects not only renewable generation projects, but more importantly the grids, distribution networks, and utilities that determine whether electricity becomes affordable, reliable, and widely accessible.
This distinction matters. In SSA, the cost of capital problem is not primarily a renewables problem- it is an electricity system problem.
The common misunderstanding: “renewables are capital-intensive”
A widely accepted narrative is that renewables are especially sensitive to financing costs because they are capital-intensive and fuel-free. This is true in principle. However, focusing only on generation economics misses the central issue in SSA.
The International Energy Agency (IEA) has repeatedly highlighted that Africa receives a disproportionately small share of global energy investment relative to its population and needs, and that financing costs are a critical barrier to scaling clean energy. But the obstacle is not simply the financing of solar or wind farms- it is the financing of entire electricity systems that struggle with weak balance sheets, currency risk, and under-investment in networks.
As a result, even where renewable generation is technically and economically attractive, electricity remains expensive and unreliable for end users.
Cheap renewable technology does not mean cheap electricity
Generation costs (LCOE) are only one component of delivered electricity prices. In many SSA countries, the dominant cost drivers are high transmission and distribution losses, weak revenue collection, under-investment in grid infrastructure, currency risk embedded in power purchase agreements, and sovereign and offtaker risk priced into tariffs.
World Bank analysis shows that many African utilities do not recover their operating and capital costs, with significant losses stemming from poor collection rates and technical inefficiencies. A subsequent study confirms that both revenue-side problems and cost-side inefficiencies drive poor utility financial performance across the region.
These weaknesses translate directly into higher perceived risk for investors. Developers price this risk into required returns. Lenders shorten tenors or increase margins. The result: even low-cost renewable generation does not translate into low-cost electricity for consumers.
This is the core paradox: SSA can have cheap renewable energy sources and expensive electricity at the same time.
Why this is an electrification problem
Electrification is fundamentally a distribution and network investment challenge. It requires expanding and reinforcing grids, financing transformers, substations, and meters, funding connections for new customers, and maintaining reliable supply. All of this requires long-tenor, low-cost capital. Yet the institutions responsible for these investments- distribution companies and utilities- are often financially fragile.
High financing costs therefore constrain electrification directly. Utilities cannot borrow cheaply to expand networks. Governments face fiscal limits in providing guarantees. Mini-grids and off-grid systems can help but often require high tariffs unless concessional finance reduces their cost of capital.
This dynamic also creates investment bias. Developers prefer commercial and industrial customers (mines, telecom towers, data centres) with hard-currency revenues and strong payment discipline. Capital flows toward self-supply solutions and away from mass electrification.
Why this is also a decarbonisation problem
Many SSA systems rely heavily on diesel and heavy fuel oil generation. In principle, these could be displaced by solar, wind, storage, and grid upgrades at lower system cost and lower emissions.
In practice, these projects require long-term finance backed by credible offtakers. When utilities are weak and currency risk is high, investors demand high returns or avoid projects altogether. Governments must then provide guarantees that strain already limited fiscal space.
The region remains locked into expensive, carbon-intensive thermal generation-not because renewables are costly, but because financing clean alternatives is risky.
What sits inside the SSA “risk premium”?
Financing costs for renewable power projects vary widely across countries. IRENA documents substantial differences in weighted average cost of capital across markets, with many African countries facing significantly higher financing costs than OECD markets.
Several factors drive this premium: offtaker risk (utilities with poor cost recovery and weak balance sheets), currency risk (local-currency revenues versus hard-currency costs), sovereign risk (debt stress limiting government guarantees), shallow capital markets (limited long-tenor local-currency finance), and policy and contract risk (concerns about enforcement and predictability).
Climate Policy Initiative highlights currency mismatch as a particularly important constraint, arguing that FX risk management is central to unlocking private capital for climate investment in EMDEs.
The real policy debate
Three broad schools of thought have emerged:
The IEA argues that reducing cost of capital in EMDEs could unlock very large investment gains and significantly lower the cost of clean energy deployment. But in SSA, the effectiveness of these tools depends critically on addressing utility fundamentals and currency risk alongside project-level de-risking.
The key insight for policymakers and industry
Sub-Saharan Africa does not primarily face a renewables financing problem. It faces an electricity system financing problem. Until the cost of capital for grids, utilities, and local-currency infrastructure falls, electrification and decarbonisation will both remain slower and more expensive than they should be-regardless of how cheap solar panels or wind turbines become.
Tariff reform, utility governance, FX risk solutions, and credible contracting frameworks are not just sector reforms. They are climate policy and electrification policy at the same time.
The bridge between electrification and decarbonisation in SSA is the cost of capital.
Dr. Rahmat Poudineh, Head of the Electricity Research Programme, Oxford Institute for Energy Studies (OIES)