Superbugs will kill more than 39 million people before 2050 with older people particularly at risk, according to a new global analysis.
While deaths linked to drug resistance are declining among very young children, driven by improvements in vaccination and hygiene, the study found the opposite trend for their grandparents.
By the middle of the century, 1.91 million people a year are forecast to die worldwide directly because of antimicrobial resistance (AMR) – in which bacteria evolve so that the drugs usually used to fight them no longer work – up from 1.14 million in 2021. AMR will play some role in 8.2 million deaths annually, up from 4.71 million.
The study, published in the Lancet was conducted by the Global Research on Antimicrobial Resistance (Gram) Project and is the first global analysis of AMR trends over time.
Researchers used data from 204 countries and territories to produce estimates of deaths from 1990 to 2021, and forecasts running through to 2050.
They also found millions of deaths worldwide could be averted via better prevention of infections and improved access to healthcare, as well as the creation of new antibiotics.
The study’s author, Dr Mohsen Naghavi, at the University of Washington’s Institute of Health Metrics (IHME), said: “Antimicrobial medicines are one of the cornerstones of modern healthcare, and increasing resistance to them is a major cause for concern.
“These findings highlight that AMR has been a significant global health threat for decades and that this threat is growing,” he said.
Global leaders will meet in New York this month to discuss antimicrobial resistance, during the UN’s general assembly. They are expected to reaffirm a political declaration on stepping up action against antimicrobial resistance, which campaigners hope will include a target to reduce AMR deaths by 10% by 2030.
The study, which involved more than 500 researchers from institutions around the world, found a “remarkable” decline in AMR deaths among children under 5 – from 488,000 to 193,000 – between 1990 and 2022. They are set to halve again by 2050.
However, while deaths due to infection in young children are fewer in number, they are increasingly likely to be caused by drug-resistant bacteria.
And death tolls are rising in all other age groups, with AMR fatalities among the over-70s already up 80% in three decades and expected to rise 146% by 2050, from 512,353 to 1.3 million.
Dr Tomislav Meštrović, assistant professor at University North in Croatia and an affiliate associate professor at the IHME, said the trend reflected rapidly ageing populations, with older people more vulnerable to infection.
“Approximately three-quarters of AMR infections are linked – for example, to hospital infections – and a rapidly ageing population also necessitates more hospital care,” he said. Older people have more chronic diseases such as diabetes and heart disease.
“For example, you put in an IV [intravenous] line, it gets infected, you get bacteria in the blood, that bacteria is likely to be more resistant,” he said.
Vaccination was often less effective in older people because the immune system deteriorated with age, he added, and older people were more prone to have reactions to antibiotics.
AMR deaths in 2021 were lower than in 2019, but the researchers said this was likely to only be a temporary reduction due to fewer infections because of Covid-19 control measures.
The study projected the highest numbers of future deaths would occur in South Asian countries such as India, Pakistan and Bangladesh, as well as other parts of southern and eastern Asia and sub-Saharan Africa.
They are among areas that have already seen the highest growth in AMR, and could also see some of the greatest benefits from improving overall infection care and widening access to antibiotics.
