Guillain-Barré syndrome after influenza vaccination in the United States, a report from the CDC/FDA vaccine adverse event reporting system (1990-2009).

OBJECTIVES: To determine the rate of Guillain-Barré syndrome (GBS) after administration of influenza vaccine in the United States and to provide further information about the characteristics and temporal profile of these incidents. METHODS: Data were acquired from the Vaccine Adverse Event Reporting System, supplemented by data from the Center for Biologics and Research under the Freedom of Information Act between 1990 and 2009. RESULTS: There were 802 cases (mean age, 54.72 ± 18.4 years) of GBS reported after influenza vaccination in the United States between 1990 and 2009. Among the 802 vaccinated patients with available data, 624 (77.8%) developed GBS within 6 weeks and 78 (9.7%) after 6 weeks, whereas these data were unavailable for the remaining 100 patients (13%). The reporting rate of post-influenza vaccine GBS was within the range expected in the general population or approximately 0.46 cases per million vaccinations. A non-Gaussian distribution of GBS within the first 6 weeks post-vaccination was noted, given that the peak incidence occurred in the second week. CONCLUSIONS: The incidence of post-influenza vaccine GBS is similar to the incidence of idiopathic GBS in the general population. Although the nonnormal distribution of post-vaccination GBS suggests that some cases may be triggered by vaccination, the greater risk of complications from influenza virus infections makes vaccination the first-line strategy for infection prevention and support the current guidelines on vaccination.

Analysis of data from the CDC/FDA vaccine adverse event reporting system (1990-2009) on Guillain-Barre syndrome after hepatitis vaccination in the USA.

We used data from the Vaccine Adverse Event Reporting System, supplemented by additional data provided by the Center for Biologics Evaluation and Research, to identify 189 patients with Guillain-Barré syndrome (GBS) reported after hepatitis vaccination with a mean age of 30.65 years, affecting men and women equally. Among vaccinated patients, 133 (70%) developed GBS within six weeks, 30 (15.9%) after six weeks, and for the remaining 26 (13.7%), the time between GBS occurrence and vaccination was not specified. The reporting rate of post-hepatitis vaccine GBS is approximately 3.4 cases per one million vaccinations, which is in the range expected in the general population. The unbalanced distribution of reports in the first six weeks after vaccination suggests that some cases of GBS may be triggered by vaccination. Nonetheless, the low incidence of hepatitis vaccine-associated GBS, and the dramatic incidence reduction of hepatitis and its complications after vaccination, support the current guidelines for vaccination.

Guillain-Barré syndrome after H1N1 vaccination in the United States: a report using the CDC/FDA Vaccine Adverse Event Reporting System (2009).

BACKGROUND: Although the Guillain-Barré syndrome (GBS) can be associated with the seasonal influenza vaccine, there is no definite evidence that GBS is associated with H1N1 influenza vaccination. The objective of this report is to study the occurrence and characteristics of GBS after H1N1 vaccine administration in the United States in 2009. METHODS: Data were acquired from the Vaccine Adverse Event Reporting System and supplemented by additional information obtained from the Center for Biologics Evaluation and Research, under the Federal Freedom of Information Act. RESULTS: A total of 62 individuals (mean age 46.51 ± 22.41 years), 33 of whom were men, developed GBS associated with the H1N1 influenza vaccination in 2009. Sixty GBS cases were reported within 6 weeks after vaccination, with 31 cases (50.0%) reported in the first 2 weeks. The estimated rate of occurrence of GBS was 6.2 cases per 10 million vaccinations, which is comparable to the rate of GBS in the general population. CONCLUSION: The higher rate of GBS reports in the first 6 weeks after H1N1 vaccination suggests that some GBS cases may be triggered by H1N1 vaccination. This warrants early recognition, treatment, and active surveillance in the postvaccination setting.

Trends in outcome and hospitalization charges of adult patients admitted with botulism in the United States.

BACKGROUND: To assess the impact of new therapeutic strategies on outcomes and hospitalization charges among adult patients with botulism in the United States. METHODS: We determined in-hospital outcomes and charges for patients with botulism hospitalized in 1993-1994 and compared them with those observed among patients hospitalized in 2006-2007. Mortality, length of stay, and hospitalization charges were calculated. Age, sex, race, ethnicity, and discharge status were also reported. RESULTS: There were 66 and 132 admissions of adult patients with botulism in 1993-1994 and 2006-2007, respectively. Men predominance was observed in 2006-2007 compared to women predominance during the 1993-1994 time period. There was no significant difference in the average length of stay and in-hospital mortality rate between the two groups studied. However, in the 2006-2007 group, there was a significant increase in the mean hospitalization charges (USD 126,092 ± 120,535 vs. USD 83,623 ± 82,084; p = 0.0107) and in the proportion of patients requiring mechanical ventilation when compared to 1993-1994 (34 vs. 13.6%; p < 0.0001). CONCLUSION: Botulism continues to be an infrequent cause of hospitalization, with a significant increase in the average hospitalization charges in 2006-2007 when compared to 1993-1994, despite a nonsignificant change in the mortality rate and average length of hospitalization.