Medical expert of the article
New publications
Vaccination against seasonal influenza increases susceptibility to other influenza strains in the future
Last reviewed: 16.10.2021
All iLive content is medically reviewed or fact checked to ensure as much factual accuracy as possible.
We have strict sourcing guidelines and only link to reputable media sites, academic research institutions and, whenever possible, medically peer reviewed studies. Note that the numbers in parentheses ([1], [2], etc.) are clickable links to these studies.
If you feel that any of our content is inaccurate, out-of-date, or otherwise questionable, please select it and press Ctrl + Enter.
The annual vaccination of children against influenza leads to the development of cross-reactive T-cells to influenza viruses, according to an article in the November Journal of Virology.
Cross-resistance - the development of resistance to an agent that entails resistance to such an agent.
In this study, author Rogier Bodewes of the medical center of Erasmus (the Netherlands) and his colleagues collected blood samples from children with cystic fibrosis who were vaccinated against influenza annually, and in healthy children as a control group who were not vaccinated. Blood samples were examined for the presence of virus-specific T-killer cells.
Most virus-specific T killer cells are directed at attacking persistent viral proteins that occur among various influenza viruses, in contrast to fast-changing, non-persistent proteins that are targets for antibodies induced by influenza vaccines.
The researchers found that in unvaccinated children, the number of virus-specific T cells increases with age, while this increase was absent in children vaccinated each year. "In fact, the vaccination, as it turned out, interfered with the induction of virus-specific T killer cells," says the author. "In vaccinated children (with cystic fibrosis), a less pronounced cross-reactive virus-specific CD8 + T cell response will develop, than in the unvaccinated. "
"Most countries recommend annual vaccination against influenza in certain high-risk groups," says Rogier Bodewes. "In addition, some countries recommend annual vaccination against influenza among all healthy children starting at six months of age."
This study showed potentially contradictory results of vaccine policy. Annual influenza vaccination is effective against seasonal influenza, but it can make people more vulnerable to the viruses of future influenza pandemics, since induction of virus-specific T-killer cells caused by influenza infection in childhood can reduce the body's resistance to pandemic influenza viruses in the future.
Referring to the report, the expert says that the results "confirm the need to develop and use universal influenza vaccines for children, especially in light of the threat of the pandemic of avian influenza A / H5N1." However, efforts to develop such a vaccine for several decades have been cornered due to the complexity of the internal orientation of proteins of influenza viruses.