Causality assessment of adverse events following immunization: the problem of multifactorial pathology [version 1; peer review: 1 approved, 2 approved with reservations, 1 not approved]

The analysis of Adverse Events Following Immunization (AEFI) is important in a balanced epidemiological evaluation of vaccines and in the issues related to national vaccine injury compensation programs. If manufacturing defects or vaccine storage and delivering errors are excluded, the majority of a...

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Main Author: Paolo Bellavite
Format: Article
Language:English
Published: F1000 Research Ltd 2020-03-01
Series:F1000Research
Online Access:https://f1000research.com/articles/9-170/v1
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author Paolo Bellavite
author_facet Paolo Bellavite
author_sort Paolo Bellavite
collection DOAJ
description The analysis of Adverse Events Following Immunization (AEFI) is important in a balanced epidemiological evaluation of vaccines and in the issues related to national vaccine injury compensation programs. If manufacturing defects or vaccine storage and delivering errors are excluded, the majority of adverse reactions to vaccines occur as excessive or biased inflammatory and immune responses. These unwanted phenomena, occasionally severe, are associated with many different endogenous and exogenous factors, which often interact in complex ways. The confirmation or denial of the causal link between an AEFI and vaccination is determined pursuant to WHO guidelines, which propose a four-step analysis and algorithmic diagramming. The evaluation process from the onset considers all possible “other causes” that can explain the AEFI and thus exclude the role of the vaccine. Subsequently, even if there was biological plausibility and temporal compatibility for a causal association between the vaccine and the AEFI, the guidelines ask to look for any possible evidence that the vaccine could not have caused that event. Such an algorithmic method presents some concerns that are discussed here, in the light of the multifactorial nature of the inflammatory and immune pathologies induced by vaccines, including emerging knowledge of genetic susceptibility to adverse effects. It is proposed that the causality assessment could exclude a consistent association of the adverse event with the vaccine only when the presumed "other cause" is independent of an interaction with the vaccine. Furthermore, the scientific literature should be viewed not as an exclusion criterion but as a comprehensive analysis of all the evidence for or against the role of the vaccine in causing an adverse reaction. These issues are discussed in relation to the laws that, in some countries, regulate the mandatory vaccinations and the compensation for those who have suffered serious adverse effects.
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spelling doaj.art-e011118e7e6a435b9664efa81b06970d2022-12-21T19:15:51ZengF1000 Research LtdF1000Research2046-14022020-03-01910.12688/f1000research.22600.124947Causality assessment of adverse events following immunization: the problem of multifactorial pathology [version 1; peer review: 1 approved, 2 approved with reservations, 1 not approved]Paolo Bellavite0Department of Medicine, Section of General Pathology, University of Verona Medical School, Verona, 37134, ItalyThe analysis of Adverse Events Following Immunization (AEFI) is important in a balanced epidemiological evaluation of vaccines and in the issues related to national vaccine injury compensation programs. If manufacturing defects or vaccine storage and delivering errors are excluded, the majority of adverse reactions to vaccines occur as excessive or biased inflammatory and immune responses. These unwanted phenomena, occasionally severe, are associated with many different endogenous and exogenous factors, which often interact in complex ways. The confirmation or denial of the causal link between an AEFI and vaccination is determined pursuant to WHO guidelines, which propose a four-step analysis and algorithmic diagramming. The evaluation process from the onset considers all possible “other causes” that can explain the AEFI and thus exclude the role of the vaccine. Subsequently, even if there was biological plausibility and temporal compatibility for a causal association between the vaccine and the AEFI, the guidelines ask to look for any possible evidence that the vaccine could not have caused that event. Such an algorithmic method presents some concerns that are discussed here, in the light of the multifactorial nature of the inflammatory and immune pathologies induced by vaccines, including emerging knowledge of genetic susceptibility to adverse effects. It is proposed that the causality assessment could exclude a consistent association of the adverse event with the vaccine only when the presumed "other cause" is independent of an interaction with the vaccine. Furthermore, the scientific literature should be viewed not as an exclusion criterion but as a comprehensive analysis of all the evidence for or against the role of the vaccine in causing an adverse reaction. These issues are discussed in relation to the laws that, in some countries, regulate the mandatory vaccinations and the compensation for those who have suffered serious adverse effects.https://f1000research.com/articles/9-170/v1
spellingShingle Paolo Bellavite
Causality assessment of adverse events following immunization: the problem of multifactorial pathology [version 1; peer review: 1 approved, 2 approved with reservations, 1 not approved]
F1000Research
title Causality assessment of adverse events following immunization: the problem of multifactorial pathology [version 1; peer review: 1 approved, 2 approved with reservations, 1 not approved]
title_full Causality assessment of adverse events following immunization: the problem of multifactorial pathology [version 1; peer review: 1 approved, 2 approved with reservations, 1 not approved]
title_fullStr Causality assessment of adverse events following immunization: the problem of multifactorial pathology [version 1; peer review: 1 approved, 2 approved with reservations, 1 not approved]
title_full_unstemmed Causality assessment of adverse events following immunization: the problem of multifactorial pathology [version 1; peer review: 1 approved, 2 approved with reservations, 1 not approved]
title_short Causality assessment of adverse events following immunization: the problem of multifactorial pathology [version 1; peer review: 1 approved, 2 approved with reservations, 1 not approved]
title_sort causality assessment of adverse events following immunization the problem of multifactorial pathology version 1 peer review 1 approved 2 approved with reservations 1 not approved
url https://f1000research.com/articles/9-170/v1
work_keys_str_mv AT paolobellavite causalityassessmentofadverseeventsfollowingimmunizationtheproblemofmultifactorialpathologyversion1peerreview1approved2approvedwithreservations1notapproved