Seasonal Variation in Exposure Incidents

The annual Laboratory Incident Notification Canada report shares data about exposure incidents occurring in licensed Canadian laboratories. An exposure incident is an event of contact with infectious material or toxins that can potentially cause:

•        harm
•        injury
•        damage
•        disease
•        infection
•        intoxication

In 2022, there were 40 reported exposure incidents, affecting 93 people of varying technical, professional, and educational backgrounds. Most occurred in the academic sector, followed by the hospital sector. The 2022 annual incident exposure rate was 3.8 incidents per 100 active licenses, a decrease from 2021.

Analysis of median incidents per month from 2016 to 2021 found that May and September had more exposure incidents, whereas June and August had fewer. These findings examine cyclical and seasonal fluctuations due to the following:

•        May is the beginning of the summer hiring period, which could involve new lab members and summer students
•        September is the beginning of the fall semester, with the return of students to academic labs
•        June and August typically have more staff on vacation, which may result in fewer incidents in labs

2022 findings fit the trend observed in the previous 6 years, with the exceptions of April and November. Both had far fewer incidents than the median of the previous 6 years.

April may be explained by:

•        reduced laboratory staff due to the Omicron variant of the SARS-CoV-2 virus, and
•        increased awareness of good biosafety and laboratory practices

November may have seen more laboratory workers on vacation as travel restrictions were eased.

For information about laboratory acquired infections and intoxications, register for the free Laboratory Acquired Infections course on PHAC's Training Portal.