The use of antibiotics in individuals with COVID-19 may result in increased antimicrobial resistance (AMR). This can involve bacteria becoming resistant to antibiotics. The effects may be felt among the wider population and have toxic consequences for the environment.
This is the main takeaway of new research conducted by a team from the University of Plymouth and the Royal Cornwall Hospitals Trust, both in the United Kingdom. The findings appear in the Journal of Antimicrobial Chemotherapy.
COVID-19 has created major problems for social and healthcare systems worldwide, and the spread of AMR is one possible consequence.
Although antibiotics are not used to treat diseases caused by viruses, patients hospitalized due to the coronavirus infections may receive a combination of these medications to prevent secondary bacterial infections. This may have serious effects on AMR.
“Common with other hospitalized patients in the U.K. and other countries, the majority of our patients with COVID symptoms were prescribed antibiotics because it is very difficult to know whether a patient presenting with symptoms of COVID has an overlying bacterial infection or not,” says Neil Powell, an author of the research and consultant pharmacist at the Royal Cornwall Hospitals Trust.
The concern about resistance has led the World Health Organization (WHO) to discourage the use of antibiotics for mild cases of COVID-19, though they still recommend their use for people with severe COVID-19 who have a risk of secondary bacterial infections and death.
Negative impact on the environment?
The present research revealed that the increased use of antibiotics during the pandemic may also be placing an added burden on wastewater treatment works.
The team noted that this could lead to raised levels of antibiotics within the U.K.’s rivers and coastal waters, which may in turn result in a rise in AMR.
This would be particularly serious in receiving waters of these works that serve large hospitals or emergency hospitals, where there are high concentrations of COVID-19 patients.
Data from UK emergency hospitals
To perform a comprehensive environmental safety assessment that addresses potential risks to fish populations and related food webs, the researchers estimated the antibiotic loads entering the wastewater treatment works.
This involved analyzing patient numbers in emergency hospitals set up temporarily around the country and taking into account the associated treatment works’ capacity and available river water dilution for the emergency hospital and associated town.
The researchers employed environmental impact data from previous research and modeling tools developed by the U.K. water industry. For illustrative purposes, they focused on a single U.K. emergency hospital: Harrogate, which has a capacity of 500 beds.
The National Institute for Health and Care Excellence COVID-19 guidelines recommend that patients with the virus receive the antibiotics doxycycline, amoxicillin, or a combination of others if their doctors suspect that a bacterial infection is present.
However, the guidelines also recommend not administering or stopping the antibiotics if no bacterial infection is found.
With these points in mind, the researchers predicted the possible effects of different scenarios involving antibiotic use during the COVID-19 pandemic — having all hospital beds occupied and having 70% or 95% of the patients receiving either doxycycline or amoxicillin.
It is important to note that amoxicillin is used to treat a wide range of bacterial infections, including pneumonia, throat infections, and skin and ear infections.
Amoxicillin and AMR — an environmental concern?
Thomas Hutchinson, a professor of environment and health at the University of Plymouth and the senior author of the research, says, “The data for amoxicillin indicated that while there was little threat of direct impacts on fish populations and other wildlife, there is a potential environmental concern for selection of AMR if at 100% capacity.”
“From our previous research, we know that significant quantities of commonly prescribed drugs do pass through treatment works and into our water courses,” adds Sean Comber, a professor of environmental chemistry at the university and the article’s lead author.
“By developing a greater understanding of their effects, we can potentially inform future decisions on prescribing during pandemics, but also on the location of emergency hospitals and wider drug and waste management,” says Prof. Comber.
Mathew Upton, a co-author and professor at the university’s School of Biomedical Sciences, concludes: “Antibiotics underpin all of modern medicine, but AMR is an issue that could impact millions of lives in the decades to come.” The author goes on to comment on the significance of the research.
“Currently, the COVID-19 pandemic is causing immense suffering and loss of life across the globe, but AMR has been — and will remain — one of the most significant threats to global human health. We conducted this study so that we can begin to understand the wider impact of global pandemics on human health.” – Prof. Mathew Upton
Finally, says Prof. Upton, “It is clear that mass prescribing of antibiotics will lead to increased levels in the environment, and we know that this can select for resistant bacteria. Studies like this are essential so that we can plan how to guide antibiotic prescription in future pandemics.”