# 5281
Amid the brewing controversy over the supposed link between GSK’s Pandemrix Vaccine and an increase in narcolepsy among children and adolescents in Finland and Sweden, we get different report from China which provides us with far more reassuring data.
Here, researchers looked for adverse reactions among 90 million recipients of China’s non-adjuvanted split-viron pandemic vaccine (By comparison, Pandemrix was an adjuvanted vaccine).
While some vaccine activists predicted huge increases in post vaccination Guillain Barre Syndrome, and warned that the vaccine would be `deadlier than the virus’, the reality has been quite different.
Researchers found no pattern of serious side effects, and no increase in Guillain Barre Syndrome.
In fact, the rate of GBS among those vaccinated was below the normal `background rate’ for the disease.
The study, led by Dr. Yu Wang - from the Chinese CDC - collected data on adverse reactions from doctors across China.
89.6 million doses of H1N1 vaccine were administered, with a total of 8,067 adverse events reported; a rate of about 90 adverse reaction per 1 million shots.
Not all of those reactions proved to be related to the shot, and when the outliers were eliminated, only 6,552 adverse reactions were attributed to the jab, or just over 73 per million doses.
And of those, more than 67.8% were considered minor; not involving hospitalization, death, life-threatening illness, or permanent disability
Of 1,083 people with more serious reactions, 1050 (96.9%) were allergic reactions of one sort or another, likely due to the ovalbumin, thimerosal, or other ingredients of the vaccine,
29 other cases with more serious vaccine reactions (rate .3 per 1 million doses) had neurologic reactions, including 8 cases with Guillain–Barré syndrome (which was lower than the expected baseline rate of GBS).
While 10 sudden deaths were reported within 9 days of vaccination, all but one had serious pre-existing medical issues including: Coronary artery disease (5), aortic aneurysm (1), decompensated hepatic cirrhosis and liver failure (1), stroke & cerebral herniation (1).
The entire study was published online in the NEJM today.
Safety of Influenza A (H1N1) Vaccine in Postmarketing Surveillance in China
Xiao-Feng Liang, M.D., Li Li, M.D., Ph.D., Da-Wei Liu, M.D., Ke-Li Li, M.D., Wen-Di Wu, M.D., Bao-Ping Zhu, M.D., Hua-Qing Wang, M.D., Ph.D., Hui-Ming Luo, M.D., Ling-Sheng Cao, M.D., Jing-Shan Zheng, M.D., Da-Peng Yin, M.D., Lei Cao, M.P.H., Bing-Bing Wu, M.D., Hong-Hong Bao, M.D., Di-Sha Xu, M.D., Wei-Zhong Yang, M.D., and Yu Wang, M.D., Ph.D.
February 2, 2011 (10.1056/NEJMoa1008553)
Background
On September 21, 2009, China began administering vaccines, obtained from 10 different manufacturers, against 2009 pandemic influenza A (H1N1) virus infection in priority populations. We aimed to assess the safety of this vaccination program.
Methods
We designed a plan for passive surveillance for adverse events after immunization with the influenza A (H1N1) vaccine. Physicians or vaccination providers were required to report the numbers of vaccinees and all adverse events to their local Center for Disease Control and Prevention (CDC), which then reported the data to the Chinese CDC through the online National Immunization Information System's National Adverse Event Following Immunization Surveillance System. Data were collected through March 21, 2010, and were verified and analyzed by the Chinese CDC.
Conclusions
No pattern of adverse events that would be of concern was observed after the administration of influenza A (H1N1) vaccine, nor was there evidence of an increased risk of the Guillain–Barré syndrome.
