Tell Me More: Serosurveillance

In this new series, Tell Me More, we discuss relevant health care topics, innovations, and trends in simple, easy to understand terms. We will share important information that you need to know and will provide insight into issues that matter to people in Ontario.

Serosurveillance
Since the onset of the COVID-19 pandemic, surveillance has been critical to tracking and preventing the spread of the virus. As experts learned more about the virus, methods of surveillance have evolved to meet the needs of all people in Ontario.

Serosurveillance, the process of testing blood samples for the presence of antibodies against a specific infectious disease, has been used to determine previous infection and/or vaccination status in a population. Serosurveillance programs are used locally and internationally not only to track COVID-19, but other infections such as viral hepatitis, measles and whooping cough. 

Serosurveillance can help inform the public health response by:

• estimating the burden of an infectious disease in a population
• identifying groups at increased risk of acquiring the disease (e.g. age, gender, geographic location, etc.)
• informing population trends in exposure to an infection over time
• evaluating the impact of vaccination programs and informing immunization policy
• supporting disease modelling and prediction of potential outbreaks
• examining trends in immunity over time

Learn more about Public Health Ontario’s COVID-19 Serosurveillance Initiative.