The study for 8 seasons (1999-2007).The risk of hospitalization due to influenza in vaccinated children was 3.67 times higher than in the unvaccinated.
For these 8 years, strain A(H3N2) has not been guessed 5 times, and the strains A (H1N1) and B did not guess four times.
Seasonal influenza vaccination increased the risk of swine flu infection by 2.5 times among children in Canada in 2009. These results were confirmed in five other studies. More: .Randomized Controlled Ferret Study to Assess the Direct Impact of 2008-09 Trivalent Inactivated Influenza Vaccine on A (H1N1) pdm09 Disease Risk. 2014, Skowronski, PLoS One
In this study we checked the previous results on ferrets, some of the ferrets were seasoned with the seasonal flu vaccine of 2008/9, and then they were infected with swine flu. Indeed, it turned out that grafted ferrets are heavier than ungrafted.Association of spontaneous abortion with receipt of inactivated influenza vaccine containing H1N1pdm09 in 2010-11 and 2011-12. 2017, Donahue, Vaccine
Vaccination against influenza during pregnancy increases the risk of miscarriage in the next 28 days by 2 times. Among those who were also vaccinated against swine flu in the last season, the risk of miscarriage was 7.7 times higher.Comparison of VAERS fetal-loss reports during three consecutive influenza seasons. 2013, Goldman, Hum Exp Toxicol
VAERS Analysis. In the 2009-10 season, when vaccinated with two flu vaccines (from conventional and from porcine), the risk of miscarriage was 11 times higher than in the 2008-9 season, and 6 times higher than in the 2010-11 season.
As a proof of the safety of a flu vaccine for pregnant women, two studies usually lead, 56 in the first, and 180 women in the second, in a thiomersal-free vaccine.The third study involved 2,291 women, but miscarriages were not included in the analysis.
It is believed that the vaccine leads to a miscarriage in 1.9 cases per million p However, these data do not take into account the fact that a negligible number of all side effects are registered in VAERS.
Risk of narcolepsy in vaccinated against swine flu in 2009 was increased 17 times. In another study the risk was increased 4-9 times. Third study showed 14-16 times narcolepsy risk increase.
A similar Swedish study found increased psychiatric comorbidity in children and adolescents with narcolepsy.
A possible explanation of this phenomenon may be that the human antibodies to nucleoprotein cross-react with human hypocretin receptor.