Number of deaths from drug-resistant bacteria expected to rise by 70% by 2050

From 1990 to 2021, antibiotic-resistant bacterial infections were responsible for over one million deaths per year worldwide. According to a systematic analysis, this number is expected to increase by almost 70% over the next 25 years.

In 2021, there were 1.14 million deaths worldwide attributed to bacterial antimicrobial resistance (AMR), slightly more than the 1.06 million AMR-related deaths in 1990, reported Christopher Murray, MD, DPhil, of the University of Washington in Seattle, and colleagues in The lancet.

Bacterial AMR was also associated with an estimated 4.71 million deaths in 2021, about the same as in 1990.

Murray and colleagues predicted that by 2050, an estimated 1.91 million AMR-attributable deaths and 8.22 million AMR-related deaths could occur annually worldwide. A total of 39.1 million deaths could be attributable to AMR between 2025 and 2050.

However, they estimated that improved access to healthcare and antibiotics could save an estimated 92 million lives between 2025 and 2050.

“These findings underscore that AMR has been a significant global health threat for decades and that this threat is growing,” co-author Mohsen Naghavi, MD, PhD, MPH, also of the University of Washington, commented in a press release.

On a positive note, deaths from AMR in children under 5 years of age decreased by 60.4% and deaths related to AMR decreased by 63.3% from 1990 to 2021. Deaths from sepsis in children under 5 years of age also decreased by more than 60% during this period.

However, deaths directly attributable to AMR among people aged 70 and over increased by 89.5% and AMR-related deaths increased by 81.3% between 1990 and 2021.

“The decline in deaths from sepsis and AMR in young children over the past three decades is an incredible achievement,” said co-author Kevin Ikuta, MD, MPH, of the University of California Los Angeles, in the press release.

“However, these findings show that while infections in young children have become less common, their treatment has become more difficult. Moreover, the threat of AMR to the elderly will only increase as the population ages,” Ikuta stressed.

In an accompanying editorial, Dr. Samuel Kariuki of the Kenya Medical Research Institute in Nairobi noted that the decline in infant deaths “corresponds to comprehensive immunization efforts and improved access to WASH programs. [water, sanitation, and hygiene]and infection prevention and control strategies that have proven highly effective in reducing the AMR burden.”

Improved access to WASH infrastructure and practices and the use of childhood vaccines could prevent about 430,000 AMR-related deaths, “both through the direct prevention of resistant infections and by reducing antibiotic use,” Kariuki wrote.

In their projections for 2050, Murray and colleagues predicted that South Asia, Latin America and the Caribbean will be the regions with the highest AMR mortality rates across all age groups. The increase in deaths attributable to AMR will be greatest among those aged 70 and over (65.9%).

However, they noted that improved access to and supplies of antibiotics could bring the greatest benefits in South Asia, sub-Saharan Africa, and parts of Southeast Asia, East Asia and Oceania.

The researchers also documented an increase in AMR-related deaths for 12 pathogens from 1990 to 2021. In 2021, the six pathogens associated with at least 100,000 AMR-related deaths annually were Staphylococcus aureus, Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae, Streptococcus pneumoniaeAnd Pseudomonas aeruginosa.

Deaths due to methicillin-resistant S. aureus AMR deaths increased the most worldwide, resulting in 130,000 deaths attributable to AMR in 2021 – double the 57,200 in 1990.

Among Gram-negative bacteria, which are among the most resistant to antimicrobial drugs, resistance to carbapenems has increased more than any other antibiotic, from 127,000 in 1990 to 216,000 in 2021. “If new antibiotics are developed for the currently antibiotic-resistant Gram-negative bacteria, an estimated 11.1 million deaths from AMR could be prevented by 2050,” Kariuki said.

S. pneumoniae The largest decline in both AMR-related and attributable deaths was seen in India, with deaths attributable to AMR falling from 258,000 in 1990 to 155,000 in 2021.

The number of deaths attributable to antibiotic resistance also varied between regions. Five regions – western sub-Saharan Africa, tropical Latin America, high-income North America, South-East Asia and South Asia – saw an increase of more than 10 000 deaths attributable to antibiotic resistance over the 31-year period. However, among children under five years of age, antibiotic resistance-attributable and related deaths decreased in all regions except Oceania. Among children aged five years and above, antibiotic resistance mortality increased in all regions except Western and Central Europe.

This global study relied on a statistical modeling approach and used 520 million individual records from a variety of sources, including hospital data, death data, antibiotic use surveys, drug sales data, insurance claims data, and published scientific studies. Murray and his colleagues examined 22 pathogens, 84 pathogen-drug combinations, and 11 infectious syndromes from 204 countries and territories.

The authors acknowledged some limitations of the analysis. The lack of data in many low- and middle-income countries was a major problem. In addition, analytical errors and selection biases may have occurred in consolidating data from a variety of sources. Projected scenarios on the AMR burden also depend on the quality and availability of historical data and do not take into account the emergence of new resistant bacterial strains.