‘Tip of the Iceberg’: Study Finds 309 Lab Infections and 16 Lab Pathogen Escape Incidents in 21 Years

Out of the 309 lab infection cases, 238 took place in the United States, which is far higher than second-placed Europe with 28 incidents.

Medical staff prepare medicine for pregnant women, infected by the COVID-19 coronavirus, at a gynecology and obstetrics isolation ward in Wuhan Union Hospital in Wuhan in China's central Hubei Province, on March 7, 2020. STR/AFP via Getty Images

A recent worldwide study has discovered that there have been several hundreds of laboratory-related infections over the past two decades, and over a dozen cases of pathogens escaping from facilities.

The peer-reviewed study, published in The Lancet Microbe on Dec. 12, analyzed several journals and media reports published between 2000 and 2021 to identify incidences of laboratory-acquired infections (LAIs) and accidental pathogen escape from laboratory settings (APELS). Out of the 94 reports analyzed, researchers identified 309 LAIs caused by 51 pathogens and 16 incidences of APELS. The findings related to LAIs were as follows:

• Out of the 309 LAI cases, the United States accounted for 238, followed by Europe with 28, and Asia with 23 incidents.
• Close to 40 percent of LAI cases occurred in an academic setting, around 25 percent in unspecified locations, and nearly 20 percent in research facilities. Over 7 percent were attributed to vaccine facilities.
• In terms of pathogens, bacteria were the leading cause of LAIs, making up 77 percent of all cases, followed by viruses at 13.9 percent.
• The leading cause of LAIs was found to be procedural errors, which accounted for close to 70 percent of incidents. Other reasons included needlestick injuries, spills, splashes, broken vials, and animal bites.

Out of the 16 APELS incidents, six involved bacteria and the remaining 10 were viral. “Generally, APELS did not cause infections, although cases of possible exposure were reported for staff members, the surrounding community, or animals,” the study noted.

“However, APELS were responsible for disease outbreaks in some cases, such as the 10,528 brucellosis infections linked to a Brucella vaccine production facility in Lanzhou, China.”

Seven out of the 16 APELS took place in the United States, with China and the UK registering two incidents each. Eleven out of the 16 incidents took place in research or university laboratories, while four occurred in vaccine production facilities.

A 1951 research into the issue found 1,342 LAI cases from 69 pathogens. While the results from the current study may suggest that LAIs and APELS have declined since 1951, this may not be the case, the researchers wrote while asking that the results be “interpreted with caution due to potential biases in voluntary reporting.”

“Without globalized formal reporting requirements, the data summarized here could only represent the tip of the iceberg,” the study said.

“The possibility also exists that LAIs could be under-reported because of an inability to discriminate between community-acquired infections or LAIs, especially when high levels of transmission are present in the community,” such as with the COVID-19 virus.

The study was funded by the Wellcome Trust and a grant to the World Organization for Animal Health (WOAH) by the Global Affairs Canada’s Weapons Threat Reduction Program. The authors declared there were no competing interests in the study.

Pathogens, Biolab Safety

The Lancet study highlighted the various pathogens involved in the LAI cases. Out of the 309 incidents, 154 were caused by Salmonella enterica Typhimurium, which is the number one cause of food poisoning in Western nations. In the United States, the pathogen causes around one million illnesses annually.

“The largest outbreak of S Typhimurium (n=109) occurred among students in microbiology teaching laboratories and employees in clinical microbiology laboratories across 38 states in the USA.”

Salmonella enteritidis came in second place and is a common cause of gastroenteritis, a type of food poisoning. Eight fatalities were recorded from the 309 cases. Procedural errors were found to be the most common cause of fatal outcomes, accounting for 62.5 percent of the deaths.

The study suggested that an “improved understanding of the causes of LAIs and APELS and implementation of suitable preventive steps and actions (including continuous improvement through formalized LAI and APELS reporting and root-cause analysis) will mitigate future occurrences.”

Researchers also recommended “incorporating robust institutional leadership, laboratory design, and risk-based practices appropriate for working with known biohazards, especially those known to cause LAIs and APELS, into laboratory management.”

The study comes as concerns about lab leak pathogens have spiked over the last years in the wake of the COVID-19 pandemic. Even as there remains no official word on the origin of the virus, a U.S. Senate report released in April 2023 stated that the virus likely leaked from the Wuhan Institute of Virology (WIV) in China.

Laboratories are classified on a scale of BSL-1 to BSL-4 depending on the safety measures they implement, with BSL-4 representing the highest safety precautions.

In a report released last year, Global Biolabs, which tracks biolabs across the world, warned that around 75 percent of existing operational BSL-4 labs are in cities where “dense populations could exacerbate the impact of an accidental release.”

“Roughly half of BSL4 labs are less than the size of a tennis court,” it stated. “Only seven BSL4 labs conduct their work solely in biosafety cabinets.”

“Overall, there are several trends that raise biosafety and biosecurity concerns given the global boom in construction of BSL4 and BSL3+ labs, particularly where biorisk management oversight is weak.”