A large study published in 2022 revealed for the first time the scale of the threat from antibiotic-resistant infections: Deaths from superbugs and other drug-evading organisms already exceeded those caused by AIDS or malaria worldwide five years ago. Two years later, research published in the same journal, The Lancetlooks back to measure the evolution of this major public health problem since 1990 and beyond, with unprecedented predictions about its impact on the future.
These are estimates that have never been made before: antibiotic resistance will directly cause 39 million deaths by 2050 and will be associated with an additional 169 million deaths, according to figures used by researchers in the project’s new research. Global research on antimicrobial resistance (GRAM). In 25 years, there will be 1.91 million deaths each year attributable to the inaction of drugs against certain types of pathogens, which represents an increase of 67.5% compared to the 1.14 million in 2021. In the same period, the number of deaths involving resistant bacteria will increase by almost 75% (from 4.71 million to 8.22 million per year).
The research also confirms the upward trend since 1990. At that time, there were 1.06 million deaths directly linked to drug resistance, 4.78 if we count the deaths in which these bacteria were involved. “The results underscore that AMR – bacterial resistance to antimicrobials – has been a major threat to global health for decades and that this threat is increasing. Understanding how mortality trends have changed over time and how they are likely to change in the future is essential to make informed decisions that help save lives,” said study author Dr. Mohsen Naghavi, leader of the AMR research team at the Institute for Health Metrics (IHME) at the University of Washington (USA).
These drugs, it should be remembered, are one of the “cornerstones of modern health care” and the phenomenon – recognized as a global health challenge – is a “cause for concern”. Resistance occurs when changes in bacteria or other pathogens make the drugs used to treat infections less effective. As a result, these diseases become more difficult to treat.
Fewer children and more adults
The new review estimates 22 pathogens, 84 pathogen-drug combinations and 11 infectious syndromes, including meningitis and sepsis, in people of all ages in 204 countries and territories. It used 520 million individual records from a variety of sources, including hospital records, death certificates and information on antibiotic use.
Deaths from methicillin-resistant S. aureus (MRSA) have increased the most worldwide, directly causing 130,000 deaths in 2021, more than double the 57,200 in 1990. Among Gram-negative bacteria, some of the most evade antimicrobial drugs because they are surrounded by a protective capsule – resistance to carbapenems has increased more than any other type of antibiotic, from 127,000 deaths in 1990 to 216,000 in 2021.
Over the entire period studied, there was only a decrease in deaths between 2019 and 2021 “due to the reduction in the burden of respiratory infections not caused by COVID”. The researchers associate this “temporary” and abnormal scenario with the social distancing measures imposed following the pandemic.
“The reduction in child deaths is an incredible achievement. However, the results show that while infections are less common, they are also more difficult to treat when they do occur.”
Dr Kevin Ikuta, author of the study
Among the most notable changes when looking at the phenomenon over time is the age of the patients. Deaths have decreased by more than 50% among boys and girls under five since 1990 – from 488,000 to 193,000 direct deaths – thanks, among other measures, to infant and youth vaccination programs. “This is an incredible achievement. However, the results show that while infections are less common in young children, they are also more difficult to treat when they do occur,” says Dr. Kevin Ikuta of the University of California, Los Angeles (UCLA) and an affiliate professor at IHME.
In contrast, deaths increased by more than 80% among adults aged 70 and older, to 519,000 in 2021, “driven by the rapid aging of the population and the greater vulnerability of older people to infections,” the researchers said. Deaths are projected to continue to rise, and it is “time to act to protect populations around the world from this threat,” Dr. Ikuta added.
92 million preventable deaths
By geographic area, those that have seen the largest increase in mortality directly linked to drug resistance – more than 10,000 between 1990 and 2021 – are the regions of Western sub-Saharan Africa, tropical Latin America, North America, Southeast Asia and South Asia. Looking ahead, estimates indicate a greater impact in South Asian countries such as India, Pakistan and Bangladesh (where 11.8 million deaths are expected between 2025 and 2050). Also in the southern and eastern part of the continent and in sub-Saharan Africa.
“Resistant infections could be implicated in around 8 million deaths per year by 2050, either as a direct cause of death or as a contributing factor. To prevent this from becoming a deadly reality, we urgently need new strategies to reduce the risk of serious infections through vaccines, new medicines, improved healthcare, better access to existing antibiotics and guidance on how to use them most effectively,” said Dr Stein Emil Vollset, one of the study’s authors and a member of the Norwegian Institute of Public Health.
The good news amid the bad forecasts is that rapid action, along with better general attention to infections and improved access to antibiotics, could prevent 92 million of these deaths. The areas that would benefit the most would be those with the worst estimates. In South Asia, there would be 31.7 million fewer deaths, according to alternative modeling of the future; 25.5 million fewer in sub-Saharan Africa; and 18.7 million in East Asia and Oceania. “In the scenario in which new antibiotics are developed against Gram-negative bacteria, estimates indicate that 11.08 million attributable deaths could be prevented globally over the same period,” the research concludes.
