Annual childhood flu vaccines may interfere with development of crossresistance

Vaccinating children annually against influenza virus interferes with their development of cross-reactive killer T cells to flu viruses generally, according to a paper in the November Journal of Virology.

In this study, first author Rogier Bodewes of Erasmus Medical Center, Rotterdam, The Netherlands and his collaborators collected blood samples from Dutch children with cystic fibrosis, who are vaccinated annually against influenza, and from healthy control children who are not vaccinated, and tested both sets of blood samples for the presence of virus-specific killer T cells. The majority of virus-specific killer T cells are directed to conserved , that is, proteins that are very similar among different , unlike the rapidly evolving, highly variable proteins which are targets of antibodies induced by .

In unvaccinated children, the investigators found that the number of virus-specific T cells rises with age, while such an increase was absent in children vaccinated annually. In fact, vaccination appeared to interfere with induction of such killer T cells, says Bodewes.

“Vaccinated children with [] will develop lower cross-reactive virus-specific CD8+ T cell responses than unvaccinated children,” says the study.

“Most countries recommend annual flu vaccination of certain high risk groups to protect against seasonal influenza,” says Bodewes. “Furthermore, some countries recommend annual influenza vaccination of all healthy children more than six months of age.”

The research points up potentially conflicting policy outcomes. Annual flu vaccines are effective against seasonal flu, but could leave people more vulnerable to novel pandemics, says Bodewes, as induction of virus-specific killer T cells caused by childhood flu infection may reduce morbidity and mortality rates from pandemic influenza viruses. Referring to the paper, he says that the findings “highlight the need for the development and use of universal influenza A virus vaccines for children, especially in light of the pandemic threat of avian influenza A/H5N1.” Nonetheless, he says that efforts to develop such vaccines have for several decades been stymied by the sheer complexity of targeting inner proteins.

More information: R. Bodewes, P.L.A. Fraaij, M.M. Geelhoed-Mieras, C.A. van Baalen, H.A.W.M. Tiddens, A.M.C. van Rossum, F.R. van der Klis, R.A.M. Fouchier, A.D.M.E. Osterhaus, and G.F. Rimmelzwaan, 2011. Annual vaccination against influenza virus hampers development of virus-specific CD8+ T cell immunity in children. J. Virol. 85:11995-12000.

add to favorites email to friend print save as pdf

Related Stories

NIH experts describe influenza vaccines of the future

Nov 17, 2010

In a review article appearing in the New England Journal of Medicine, scientists at the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, examine research under way to ...

Human trials of universal flu vaccine begin

Sep 08, 2008

Clinical trials of a new vaccine that could protect against multiple types of flu are beginning at Oxford University. If successful, the ‘universal’ flu injection would transform the way we vaccinate against ...

Bird flu vaccine protects people and pets

Oct 20, 2008

A single vaccine could be used to protect chickens, cats and humans against deadly flu pandemics, according to an article published in the November issue of the Journal of General Virology. The vaccine protects birds and ma ...

Recommended for you

US looking past Ebola to prepare for next outbreak

6 hours ago

The next Ebola or the next SARS. Maybe even the next HIV. Even before the Ebola epidemic in West Africa is brought under control, U.S. public health officials are girding for the next health disaster.

Can robots help stop the Ebola outbreak?

14 hours ago

The US military has enlisted a new germ-killing weapon in the fight against Ebola—a four-wheeled robot that can disinfect a room in minutes with pulses of ultraviolet light.

New bird flu case in Germany

14 hours ago

A worrying new strain of bird flu has been observed for the first time in a wild bird in northern Germany, the agriculture ministry said Saturday.

Mali announces new Ebola case

Nov 22, 2014

Mali announced Saturday a new case of Ebola in a man who is fighting for his life in an intensive care unit in the capital Bamako.

Plague outbreak kills 40 in Madagascar: WHO

Nov 22, 2014

An outbreak of plague has killed 40 people in Madagascar, the World Health Organization said, warning that the disease could spread rapidly in the country's densely populated capital Antananarivo.

User comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.