How drug-resistant pathogens in water could spark another pandemic

UNEP - United Nations Environment Programme - 4/12/2022 12:40:00 PM

People around the world are unknowingly being exposed to water laced with antibiotics, which could spark the rise of drug-resistant pathogens and potentially fuel another global pandemic, warns a report from the United Nations Environment Programme (UNEP).

The study, released last month, ahead of World Health Day on 7 April, found that, globally, not enough attention is being focused on the threat posed by antimicrobial resistance with most antibiotics being excreted into the environment via toilets or through open defecation. In 2015, 34.8 billion daily doses of antibiotics were consumed, with up to 90 per cent of them excreted into the environment as active substances.

While 80 per cent of wastewater in the world is not treated, even in developed countries treatment facilities are often unable to filter out dangerous bugs. This could breed superbugs that can evade modern medicine and trigger a pandemic, the report's authors warned.

Antibiotics and other drugs are lifesavers but need to be used carefully to prevent antimicrobial resistance that poses social, environmental and financial risks to businesses and society at large.

Leticia Carvalho, head of UNEP's Marine and Freshwater Branch
In 2019, antibiotic-resistant infections were linked to the deaths of nearly 5 million people. Without immediate action, those infections could cause up to 10 million deaths per year by 2050, the report found. "Another pandemic is hiding in plain sight," the report said. "The consequences of the continuing development and spread of anti-microbial resistance could be catastrophic."

Antimicrobials are agents intended to kill or inhibit the growth of pathogens. They include antibiotics, fungicides, antiviral agents, parasiticides, as well as some disinfectants, antiseptics and natural products.

Antimicrobial resistance occurs when microbes, such as bacteria, viruses, parasites and fungi evolve to become immune to the drugs to which they were previously susceptible. The more microbes are exposed to pharmaceuticals, the more likely they are to adapt to them.

"Antibiotics and other drugs are lifesavers but their environmental fate in the course of our waters matter. They need to be used carefully to prevent antimicrobial resistance that poses social, environmental and financial risks to businesses and society at large," said Leticia Carvalho, Head of UNEP's Marine and Freshwater Branch.

What can be done?

According to the report, this global threat can be tackled by curbing the release of antibiotic-tinged pollution, including through improved wastewater treatment and more targeted use of antibiotics - too often these drugs are used when they need not be. The report recommended improving data and monitoring of antimicrobials and how they are disposed of. It also called for enhanced environmental governance and national action plans to limit the release of antimicrobials.

The report urged countries to embrace the One Health approach, which is centred on the idea that human and animal health are interdependent and linked to the health of the ecosystems in which they co-exist. The strategy, for example, calls on countries to limit deforestation, which often brings humans face-to-face with virus-carrying wild animals, giving pathogens a chance to jump species.

"The COVID-19 pandemic provides lessons learned, one of which is the need to prevent and tackle various health threats concurrently, especially their environmental dimensions," the report said.

Five main sources

A computer generation image of microbes
A computer generated image of microbes. Photo: CDC
A recent study on pharmaceutical pollution of the world's rivers concluded that higher levels of antibiotic-resistant pathogens were found in low- to middle-income countries and were associated with areas with poor wastewater and waste management infrastructure and pharmaceutical manufacturing.

According to the UNEP report, five main pollutant sources contribute to the development and spread of antimicrobial resistance. They are:

poor sanitation, sewage and waste effluent, aggravated, for example, by open defecation and the overuse of antibiotics to treat diarrhoea;

Climate change dimensions

Higher temperatures are also associated with increased antimicrobial resistant infections, says the report. Many diseases are climate-sensitive, and changes in environmental conditions and temperature may lead to an increase in the spread of bacterial, viral, parasitic, fungal and vector-borne diseases.

UNEP joins alliance to implement One Health approach
Severe weather events and rising water tables can cause wastewater and sewage to overwhelm treatment plants, allowing untreated sewage rich in antimicrobial resistant microbes to contaminate surrounding communities.

The report, which presents highlights from a more detailed study to be released later this year, urged policymakers not to let down their guard, even as the COVID-19 pandemic recedes.It said: "The COVID-19 pandemic is a wake-up call to better understand and improve all areas of preparedness for and prevention of infectious diseases, including their environmental dimensions."

Tackling the pollution crisis forms a core pillar of UNEP's new global strategic priorities for water, and antimicrobial resistance is specifically included in UNEPs 2022-2025 Medium-Term Strategy under Chemicals and Pollution Action. The "One Health" approach, supported by UNEP, is a cross-cutting and systemic approach based on the fact that human health and animal health are interdependent and linked to the health of the ecosystems in which they co-exist.

Since 1978, UNEP has run the Global Environment Monitoring System for Freshwater (GEMS/Water) Programme, mandated to support Member States in monitoring and assessing their water quality and reporting their data to UNEP's global database on water quality.

The World Water Quality Alliance, launched by UNEP in 2019, advocates the central role of freshwater quality in achieving prosperity and sustainability, and is tasked with preparing a World Water Quality Assessment. The Global Wastewater Initiative, for which UNEP provides Secretariat services, is raising awareness on antimicrobial resistance.

To fight the pervasive impact of pollution on society, UNEP launched #BeatPollution, a strategy for rapid, large-scale and coordinated action against air, land and water pollution. The strategy highlights the impact of pollution on climate change, nature and biodiversity loss, and human health. Through science-based messaging, the campaign showcases how transitioning to a pollution-free planet is vital for future generations.

The World Health Organization (WHO) in collaboration with the Food and Agriculture Organization of the United Nations (FAO), the World Organisation for Animal Health (OIE) and UNEP have developed a Strategic Framework for collaboration on antimicrobial resistance (AMR).