Quantitative COVID-19 vaccine safety surveillance with VigiLyze

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For further assistance or any questions, write to us at vigibase@who-umc.org

VigiLyze is only available to national pharmacovigilance centres
that are members of the WHO PIDM

Uppsala Monitoring Centre (UMC) is committed to supporting members of the WHO Programme for International Drug Monitoring (WHO PIDM) in their COVID-19 vaccine safety surveillance efforts. We recognise the challenges faced by member countries, given the large numbers of incoming reports of adverse events following immunisation related to COVID-19 vaccines, and understand that a case-by-case approach to signal detection may no longer be feasible. 

Therefore, we have made essential improvements in VigiLyze to enable statistical screening of your national subset of the WHO global database, including powerful methods for prioritisation. To use these features, it is essential that the data is shared as recommended by the WHO Safety Surveillance Manual for COVID-19 vaccines. The improvements we have made in our data management system, VigiFlow, support the required workflow and data processing, including batch sharing of data (read more about VigiFlow improvements here). If you would you like to learn how you can share data more efficiently with VigiBase, you are welcome to contact us at vigibase@who-umc.org.

The major changes

Traditionally, in pharmacovigilance, statistical screening for medicines is done at the active ingredient – preferred term – level, and all disproportionality calculations in the Quantitative work area have been provided at this level. However, for vaccines, the active ingredient level does not allow for screening for multiple individual vaccines that may be available for use to protect against the same disease. We have now addressed this limitation, making it possible to see disproportionality calculations for individual vaccines, including the COVID-19 vaccines, separately, using a new feature in VigiLyze, the “active ingredients variant” option.

Exploration of disproportionality at the level of individual vaccines is available using the Quantitative workflow, using the AI variants toggle option in the upper right-hand corner of the tool. Currently, the naming of individual vaccines at the AI variants level appears complex in VigiLyze due to differences in regulatory requirements between countries so, to improve usability, we provide a reference guide for ease of identification in VigiLyze.

How to

As a starting point, go to Quantitative view and search for COVID-19 vaccine. It is now possible to prioritise your review of the vaccine-reactions combinations table in your Quantitative view to focus on serious or other events of special interest. You can do this using a number of options:

  • Important Medical Events: Filter button -> Reaction -> Important Medical Events
  • Sort the list of combinations using the Nserious or the Nfatal columns
  • Custom groups: Create a Custom reactions group of adverse events of your choice, such as the designated Adverse Events of Special Interest (AESI) for COVID-19 vaccines as described by the Brighton Collaboration.

Another tip to focus your efforts on what is not labelled is to create an investigation for each individual vaccine with all the MedDRA PT terms that are already labelled. This requires some initial efforts but may quickly pay off, as you can then automatically filter them out from your combinations list. Unfortunately, it is not possible to add this information automatically in VigiLyze because the Investigations are organisation specific and labels may vary between countries. If you need an introduction on how to work with the Investigations, please reach out to us.

Last modified on: June 29, 2022