Pollution, climate change feed drug-resistant 'superbugs'

Just as the world appears to be emerging from worst of the COVID-19 pandemic, the United Nations is warning of an impending health crisis that by mid-century could pose an even greater threat and kill as many people a year as cancer.

Nourished, developed and spread by pollution from farming, pharma and health care, superbugs – strains of bacteria that have become resistant to all known antibiotics – could cause as many as 10 million deaths each year by 2050.

Higher temperatures can be associated with increases in these kinds of infections, and extreme weather patterns can contribute to its emergence and spread, the U.N. Environment Program, or UNEP, said in a new report on Tuesday.

And the potential devastation goes further; the widespread proliferation of these organisms could lead to production losses of at least US$3.4 trillion a year.

But there's a solution. Reducing pollution in drug-making, agriculture and health care can cut back on superbugs and other antimicrobial resistance, known as AMR.

Barbados' Prime Minister Mia Mottley told a press briefing to launch the report that the world takes so much progress for granted in health, food and prosperity over the past century.

“We are, however, confronted by a silent, slow-motion pandemic,” she said, referring to the threat of AMR. "This report seeks to ensure that we are far more sensitive to the realities of what is taking place in the environment. The pollution of water, air and soil doesn't just affect local communities."

Mottley, speaking on the sidelines of a meeting in Bridgetown, Barbados, of the Global Leaders Group on Antimicrobial Resistance that she chairs, called it a huge problem the world needs to address immediately.

"Our greatest fear is that by 2050 it may well become the leading cause of death in the world," she said.

The development and transmission of AMR means that antimicrobials used now to prevent and treat infections in humans, animals and plants might become ineffective, leaving modern medicine incapable of treating even mild infections.

Superbugs already are one of the top threats to global health. They are associated with 5 million deaths a year – making AMR the third leading cause of death globally. The World Bank estimates the damage could force 24 million more people into extreme poverty – living on less than US$1.90 a day.

"The same drivers that cause environment degradation are worsening the antimicrobial resistance problem," said Inger Andersen, the head of UNEP, citing the effects of air, soil and water pollution. "Cutting down pollution is a prerequisite for another century of progress towards zero hunger and good health."

Superbugs and the environment

The study offers measures to address environmental degradation and superbugs that emerge from inadequate sanitation and poor sewage and waste control.

These include increasing global efforts to improve water and sanitation management aimed specifically at reducing the spread of AMR, and establishing international standards for what constitutes a good microbiological indicator of AMR from environmental samples.

While attention to AMR is primarily focused on human health and agriculture, UNEP reports growing evidence that the environment plays a key role in the development, transmission and spread of superbugs. Their rise is linked closely to climate change, biodiversity and nature loss, and pollution driven by human activity.

Due to the overuse of medicines, livestock farming is a major source of bacteria strains that have become resistant to all forms of antibiotics. Waterways polluted with pharmaceutical products also is a key contributor, with superbugs resistant to antibiotics surviving in untreated sewage and waste.

"This report calls for priority action to address key pollution sources from poor sanitation, sewage; community and municipal wastes; healthcare delivery; pharmaceutical manufacturing; intensive crop, and terrestrial and aquatic animal production sectors," the study says.

"There are many co-benefits of preventing and managing pollution in these sources to address biological wastes that contain resistant microorganisms that spread AMR, and chemical wastes that select for AMR," it says.

UNEP cites global warming and AMR as two of the biggest and most complex threats facing our world. Higher temperatures have been associated with increases in AMR infections, and extreme weather patterns can contribute to the emergence and spread of superbugs.

Additionally, antimicrobial impacts on microbial biodiversity may affect the cycles of carbon and methane, which are directly involved in regulating Earth's climate, the report says.