We're unable to sign you in at this time. Please try again in a few minutes.
We were able to sign you in, but your subscription(s) could not be found. Please try again in a few minutes.
There may be a problem with your account. Please contact the AMA Service Center to resolve this issue.
Contact the AMA Service Center:
Telephone: 1 (800) 262-2350 or 1 (312) 670-7827  *   Email: subscriptions@jamanetwork.com
Error Message ......
Article |

Efficacy of Inactivated Vaccine in Preventing Antigenically Drifted Influenza Type A and Well-Matched Type B

Norio Sugaya, MD; Kuniaki Nerome, PhD; Masatoshi Ishida, PhD; Miyako, PhD; Keiko Mitamura, MD; Mari Nirasawa, MD
JAMA. 1994;272(14):1122-1126. doi:10.1001/jama.1994.03520140052037.
Text Size: A A A
Published online


Objective.  —To evaluate the efficacy of currently used inactivated influenza vaccine during a severe epidemic caused by antigenically drifted influenza type A(H3N2) and well-matched type B viruses during the 1992-1993 season.

Design.  —Prospective nonrandomized controlled trial.

Setting.  —An urban general hospital pediatric asthma clinic in Japan.

Participants.  —A total of 137 children with moderate to severe asthma (mean age, 7.0 years; range, 2 to 14 years).

Interventions.  —Eighty-five children received trivalent split-antigen vaccine containing A/Beijing/352/89 (H3N2) and B/Bangkok/163/90 (B/Panama/45/90—like strain). Fifty-two were unvaccinated.

Main Outcome Measures.  —Protection against infection was determined using hemagglutination inhibition test and virus isolation. Clinical efficacy was estimated based on febrile episodes with antibody rise or virus isolation.

Results.  —Although marked antigenic drift in hemagglutinin was demonstrated in the epidemic virus (A/Beijing/32/92—like strain), the protection against influenza type A(H3N2) infection was 67.5% (P<.01). The protection against influenza type B infection was 43.7% (P<.01), although the epidemic influenza type B viruses were antigenically almost identical to the vaccine strain. Inactivated vaccine was not effective for protection against influenza type B infection in children younger than 7 years. High clinical effectiveness was demonstrated in children at least 7 years of age during the epidemic.

Conclusions.  —Our data suggest that current inactivated vaccine is highly effective for protection against influenza type A(H3N2) virus infection regardless of antigenic drift. In contrast, the protective efficacy obtained by vaccination may not be sufficient against influenza type B virus infection, and especially in young children, it does not offer protection.(JAMA. 1994;272:1122-1126)


Sign in

Purchase Options

• Buy this article
• Subscribe to the journal
• Rent this article ?




Also Meets CME requirements for:
Browse CME for all U.S. States
Accreditation Information
The American Medical Association is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. The AMA designates this journal-based CME activity for a maximum of 1 AMA PRA Category 1 CreditTM per course. Physicians should claim only the credit commensurate with the extent of their participation in the activity. Physicians who complete the CME course and score at least 80% correct on the quiz are eligible for AMA PRA Category 1 CreditTM.
Note: You must get at least of the answers correct to pass this quiz.
Please click the checkbox indicating that you have read the full article in order to submit your answers.
Your answers have been saved for later.
You have not filled in all the answers to complete this quiz
The following questions were not answered:
Sorry, you have unsuccessfully completed this CME quiz with a score of
The following questions were not answered correctly:
Commitment to Change (optional):
Indicate what change(s) you will implement in your practice, if any, based on this CME course.
Your quiz results:
The filled radio buttons indicate your responses. The preferred responses are highlighted
For CME Course: A Proposed Model for Initial Assessment and Management of Acute Heart Failure Syndromes
Indicate what changes(s) you will implement in your practice, if any, based on this CME course.


Some tools below are only available to our subscribers or users with an online account.

0 Citations

Sign in

Purchase Options

• Buy this article
• Subscribe to the journal
• Rent this article ?

Related Content

Customize your page view by dragging & repositioning the boxes below.