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ARTICLES: Pedro A. Piedra, Manjusha J. Gaglani, Claudia A. Kozinetz, Gayla B. Herschler, Charles Fewlass, Dianne Harvey, Nadine Zimmerman, and W. Paul Glezen Trivalent Live Attenuated Intranasal Influenza Vaccine Administered During the 2003–2004 Influenza Type A (H3N2) Outbreak Provided Immediate, Direct, and Indirect Protection in Children Pediatrics 2007; 120: e553-e564 [Abstract] [Full text] [PDF]

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Questioning the reliability of inactivated influenza vaccine effectiveness measure

Alexander Goldstein   (14 August 2007)

Questioning the reliability of inactivated influenza vaccine effectiveness measure [corrected]

Alexander Goldstein   (15 August 2007)

Questioning the reliability of inactivated influenza vaccine effectiveness measure 14 August 2007
Alexander Goldstein, Moscow, Russia sanofi pasteur Send letter to journal: Re: Questioning the reliability of inactivated influenza vaccine effectiveness measure alexander.goldstein{at}sanofipasteur.com Alexander Goldstein	I disagree with the authors of the paper in the method of assesement of inactivated influenza vaccine (IIV) effectiveness. It is widely known that immune response after administration of IIV peaks after first 2 weeks after vaccination (Fukuda K. et al. Inactivated Influenza Vaccine. In: Plotkin SA, Orenstein WA (eds). Vaccines. 4th ed., 2004). So cases of influenza (clinically or laboratory-confirmed) occured during first 14 days after IIV vaccination usually are not included in the analysis of IIV effectiveness becuse during that time recipients are not yet fully protected or not protected at all. This factor is particularly important in this study, because recipients of IIV were not healthy adults but children, which had, in addition, chronic medical conditions (in which we can propose slower kinetics of immune response). Furthermore, as noted by the authors in the Discussion chapter, part of the children from the IIV group were not vaccinated according to the recommended schedule as persons <9 y.o., which have not been immunized against influenza previously, should recieve 2 doses of the vaccine. Inclusion in the analysis cases of influenza, which occured: 1) during first 14 days after receipt of IIV and 2) in not fully vaccinated children (the number of such cases is not stated in the paper) would surely lead to underestimation of IIV effectiveness and that occured in this sudy. As we can see in table 4, 7 of 14 laboratory-confirmed cases of influenza in IIV recipients occured within 14 days after vaccination (6 of that 7 - durind 1st week after vaccination). If they were not included in the analysis of IIV effectiveness (table 3), the latter will be far from zero and amount 47%. Such effectiveness, accounting for underlying chronic medical conditions in vaccine recipients and influenza vaccine strain and circulating strain mismatch, can be considered as satisfactory. Conflict of Interest: Employee of sanofi pasteur.
Questioning the reliability of inactivated influenza vaccine effectiveness measure [corrected] 15 August 2007
Alexander Goldstein, Moscow, Russia sanofi pasteur Send letter to journal: Re: Questioning the reliability of inactivated influenza vaccine effectiveness measure [corrected] alexander.goldstein{at}sanofipasteur.com Alexander Goldstein	I would like to edit my P3R. Corrected response should be the following: I disagree with the authors of the paper in the method of assesement of inactivated influenza vaccine (IIV) effectiveness. It is widely known that immune response after administration of IIV peaks after first 2 weeks after vaccination (Fukuda K. et al. Inactivated Influenza Vaccine. In: Plotkin SA, Orenstein WA (eds). Vaccines. 4th ed., 2004). So cases of influenza (clinically or laboratory-confirmed) occured during first 14 days after IIV vaccination usually are not included in the analysis of IIV effectiveness becuse during that time recipients are not yet fully protected or not protected at all. This factor is particularly important in this study, because recipients of IIV were not healthy adults but children, which had, in addition, chronic medical conditions (in which we can propose slower kinetics of immune response). Furthermore, as noted by the authors in the Discussion chapter, part of the children from the IIV group were not vaccinated according to the recommended schedule as persons <9 y.o., which have not been immunized against influenza previously, should recieve 2 doses of the vaccine. Inclusion in the analysis cases of influenza, which occured: 1) during first 14 days after receipt of IIV and 2) in not fully vaccinated children (the number of such cases is not stated in the paper) can lead to underestimation of IIV effectiveness. This response represents only opinion of its author and do not represent position of sanofi pasteur. Conflict of Interest: Employee of sanofi pasteur.