A study published in the journal Clinical Infectious Diseases found that:
[C]hildren who received the trivalent inactivated influenza vaccine (TIV) had no reduction in the flu, but had over 4 times the risk of contracting an acute respiratory illness (ARI)
This echoes another study published in the journal Allergy and Asthma Proceedings which also found that:
TIV[trivalent influenza vaccine] did not provide any protection against hospitalization in pediatric subjects, especially children with asthma. On the contrary, we found a threefold increased risk of hospitalization in subjects who did get the TIV vaccine.”
Some of the viruses that flu vaccine recipients were more susceptible to included:
- Rhinovirus (the common cold)
- Coxsackie/echoviruses (Coxsackie A causes hand,foot and mouth disease, Coxsackie B can led to serious heart conditions)
- “Other” respiratory viruses.
Essentially what happens when you give your child a flu vaccine is you cause the body’s immune system to expend energy generating antibodies to something it may not ever encounter. It then has less resources to tackle the microbes that you actually are encountering. This is the likely reason that you become more susceptible to a variety of other infections.
Of further importance, another study published in the same journal found that the flu vaccine was less effective if you’ve been vaccinated for the flu in the last 5 years. According to the authors:
[T]he analysis using 5 years of historical vaccination data suggested a significant difference in current-season vaccine effectiveness among frequent vaccinees compared with nonvaccinees. Interference due to repeated prior vaccination is one possible explanation for this difference.
Therefore, if you just vaccinate your child every year for the flu under the assumption that it will help prevent your child from getting sick, not only will it not prevent your child from getting sick, it will make your child more likely to get sick. Then, if a truly deadly flu virus does circulate one year (in which case vaccination could make a difference between life or death), your child will be less protected from that virus than a child who waited for a serious flu before getting vaccinated.
During your run-of-the-mill seasonal influenza years, if you are looking for a more effective way to fight influenza viruses, properly prescribed Chinese herbs can help. Chinese herbal medicine has been shown to be very effective at inhibiting many influenza viruses and can do so without compromising your immune system’s ability to fight.
 See, e.g., https://www.ncbi.nlm.nih.gov/pubmed/21232589