Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Effectiveness of chickenpox vaccine decreases after one year

18.02.2004


The effectiveness of the chickenpox vaccine decreases significantly in the first year after vaccination, and also appears lower if the vaccine is administered to children younger than 15 months of age, according to a study in the February 18 issue of The Journal of the American Medical Association (JAMA).



According to background information in the article, chickenpox (varicella) vaccine is recommended for routine administration to healthy children at 12 to 18 months of age and to older children who have not yet had chickenpox. Recent reports of outbreaks of chickenpox in groups with substantial rates of immunization have increased concern about the effectiveness of the current recommendations for administration of the vaccine.

Marietta Vazquez, M.D., of the Yale University School of Medicine, New Haven, Conn., and colleagues examined the influence of age at the time of chickenpox vaccination and the time since vaccination on the vaccine’s effectiveness. The study, conducted from March 1997 through June 2003, included 339 children 13 months or older who were clinically diagnosed as having chickenpox. For each case subject, two controls were selected, matched by both age and pediatric practice.


The researchers found that although the overall effectiveness of the vaccine was 87 percent, there was a substantial difference in the vaccine’s effectiveness in the first year after vaccination (97 percent) and in years 2 to 8 after vaccination (84 percent). "The vaccine’s effectiveness in year 1 was substantially lower if the vaccine was administered at younger than 15 months (73 percent) than if it was administered at 15 months or older (99 percent), although the difference in effectiveness overall for children immunized at younger than 15 months was not statistically significantly different than for those immunized at 15 months or older (81 percent vs. 88 percent). Most cases of chickenpox in vaccinees were mild," the authors write.

" … in the United States, deaths from varicella and other complications in immunocompetent persons still occur and will continue to occur until the infection is eliminated. It is important to monitor closely the incidence of varicella and the effectiveness of the vaccine over time to determine if a booster dose is needed to improve its effectiveness," the researchers write.


Editor’s Note: For funding and disclosure information of the authors, please see the JAMA article.

For more information: Contact the JAMA/Archives Media Relations Department at 312-464-JAMA (5262) or email: mediarelations@jama-archives.org.

Karen Peart | EurekAlert!
Further information:
http://jama.com/

More articles from Studies and Analyses:

nachricht Rutgers-led innovation could spur faster, cheaper, nano-based manufacturing
14.02.2018 | Rutgers University

nachricht New study from the University of Halle: How climate change alters plant growth
12.01.2018 | Martin-Luther-Universität Halle-Wittenberg

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Attoseconds break into atomic interior

A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.

In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...

Im Focus: Good vibrations feel the force

A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.

By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...

Im Focus: Developing reliable quantum computers

International research team makes important step on the path to solving certification problems

Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Basque researchers turn light upside down

23.02.2018 | Physics and Astronomy

Finnish research group discovers a new immune system regulator

23.02.2018 | Health and Medicine

Attoseconds break into atomic interior

23.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>