Bacterial infections become the 2nd leading cause of death in the world, says study

Common bacterial infections have become the second leading cause of death and were associated with one in eight deaths worldwide in 2019, according to an analysis published in the scientific journal The Lancet.

That year, 7.7 million deaths associated with 33 bacterial infections common, with just five bacteria being linked to more than half of all deaths. According to the study, the most deadly bacterial agents and types of infection varied according to the location and age of the patients.

Bacterial infections were second only to ischemic heart disease which remained the leading cause of death in 2019. Experts point out that the reduction in injuries must be a global public health priority.

According to the authors, building stronger health systems with greater diagnostic laboratory capacity, implementing control measures and optimizing the use of antibiotics are some of the essential measures to decrease the burden of diseases caused by common bacterial infections.

“For the first time, these new data reveal the full extent of the global public health challenge posed by bacterial infections,” said Christopher Murray, study co-author and director of the Institute for Health Metrics and Evaluation (IHME) at the School of Medicine at the University of Washington, in a statement. “It is critically important to get these results on the radar of global health initiatives so that a deeper dive into these deadly agents can be conducted and adequate investments can be made to reduce the number of deaths and infections.”

Although there are many estimates for causes of diseases such as tuberculosis, malaria and HIV, until now estimates of the burden of bacterial agents were limited to a restricted set and specific types of infection or focused only on certain populations.

More deaths have been linked to two of the deadliest agents – Staphylococcus aureus and Escherichia coli – than HIV/AIDS (864,000 deaths) in 2019. However, the study points out, the analysis shows that HIV research received $42 billion, while HIV research E coli received $800 million. The authors say these funding gaps may have arisen because, until now, there has been a lack of data on the global burden of these infections.

overall mortality

The new study provides the first global estimates of mortality associated with 33 common bacterial agents and 11 major types of infection – known as infectious syndromes – leading to death from sepsis, a widespread infection that can spread rapidly and have harmful impacts on many organs.

Estimates were collected for all ages and sexes in 204 countries and territories. Utilizing data and methods from the 2019 Global Burden of Disease Studies and the Global Antimicrobial Resistance Survey (GRAM), researchers used 343 million individual and isolated records of disease-causing agents—known technically as pathogens—to estimate the associated deaths and the type of infection responsible.

Of the estimated 13.7 million infection-related deaths that occurred in 2019, 7.7 million were associated with the 33 bacterial pathogens studied. Deaths associated with these bacteria accounted for 13.6% of all global deaths and more than half of all sepsis-related deaths in 2019. More than 75% of the 7.7 million bacterial deaths were due to three syndromes: lower respiratory infections , bloodstream infections, and peritoneal and intra-abdominal infections.

Five pathogens – s. aureus🇧🇷 E coli🇧🇷 Streptococcus pneumoniae🇧🇷 Klebsiella pneumoniae and Pseudomonas aeruginosa – were responsible for 54.2% of deaths among the studied bacteria. The agent associated with the highest number of deaths globally was s. aureus, with 1.1 million deaths. Four other microorganisms have been linked to more than 500,000 deaths each: E coli (950,000 deaths), S. pneumoniae (829,000), K. pneumonia (790,000) and P. aeruginosa (559,000). A similar number of female and male deaths were associated with the main bacterial agents.

Age-standardized death rates varied by location, as did the deadliest microorganisms, the study points out.

Sub-Saharan Africa recorded the highest death rate, with 230 deaths per 100,000 population. By comparison, the high-income super-region – which includes countries in Western Europe, North America and Australasia – recorded the lowest death rate, with 52 deaths per 100,000 population.

s. aureus was the leading bacterial cause of death in 135 countries, followed by E coli (37 countries), S. pneumoniae (24 countries) and K. pneumoniae and Acinetobacter baumannii (4 countries each).

“Until now, country-level estimates for parts of the world where people are most affected by bacterial infections have been noticeably absent,” said Authia Gray, study co-author and IHME post-baccalaureate at the University of Washington School of Medicine. “These new data can act as a guide to help address the disproportionately high burden of bacterial infections in low- and middle-income countries and can ultimately help save lives and prevent people from losing years of their lives due to disease,” he adds.

Bacterial resistance

Resistance of microorganisms to antibiotics is one of the greatest threats to global health today. The problem is directly associated with the excessive and incorrect use of available antibiotics. The increase in the number of drug-resistant bacteria, popularly called superbugs, puts the health of humans and animals around the world at risk.

Antibiotics are drugs capable of killing or inhibiting the growth of bacteria. Its effectiveness is directly associated with the agent causing the infection. Resistance to antibiotics happens when certain bacteria change in response to the use of drugs.

“It is the bacteria that become resistant, not humans. With the inappropriate use of antibiotics, a ‘selection’ process can occur: while the ‘sensitive’ bacteria are eliminated from the treatment, the ‘resistant’ ones remain and multiply”, explains researcher Ana Paula Assef, from the Research Laboratory in Hospital Infection at the Oswaldo Cruz Institute (IOC/Fiocruz), in Rio de Janeiro.

The World Health Organization (WHO) promotes until November 24th the World Week for the Conscious Use of Antibiotics (World Antibiotic Awareness Week). The objective of the campaign is to make the population, health professionals and public managers aware of the resistance caused by the indiscriminate use of antibiotics.