ABSTRACT
The role of vaccination in the development of Guillain-Barré syndrome (GBS) is controversial, although cases of GBS have been reported following a wide range of vaccines. A nested case-control study was conducted between January 2011 and December 2015 in three Chinese cities. Four controls were matched to a case by gender, age, address and index date. An independent expert committee validated the diagnoses of cases and controls according to the Brighton Collaboration GBS case definition. Data on vaccinations were obtained from computerized vaccination records. Causal relations were assessed by conditional logistic regression. 1056 cases of GBS and 4312 controls were included in the analyses. Among paediatric and adult population, adjusted ORs for GBS occurrence within 180 days following vaccination were 0.94 (95% CI 0.54-1.62) and 1.09 (95% CI 0.88-1.32), respectively. No increased risk of GBS was detected for vaccination against hepatitis B, influenza, hepatitis A, varicella, rabies, polio(live), diphtheria, pertuss(acellular), tetanusis, measles, mumps, rubella, Japanese Encephalitis, and meningitis vaccines. Adjusted ORs for the recurrence of GBS after vaccination among paediatric and adult population were 0.85 (95% CI 0.07-9.50) and 1.18 (95% CI 0.49-2.65), respectively. In this large retrospective study, we did not find evidence of an increased risk of GBS and its recurrence among either paediatric (≤ 18 years) or adult (> 18 years) individuals within the 180 days following vaccinations of any kind, including influenza vaccination.
Subject(s)
Guillain-Barre Syndrome/chemically induced , Influenza Vaccines/adverse effects , Influenza, Human/complications , Vaccination/adverse effects , Adolescent , Adult , Case-Control Studies , Child , China/epidemiology , Female , Humans , Influenza A Virus, H1N1 Subtype , Influenza, Human/epidemiology , Male , Middle Aged , Retrospective Studies , Risk FactorsABSTRACT
BACKGROUND: It is important to examine the risk of Acute disseminated encephalomyelitis (ADEM) after vaccination. METHODS: We conducted a nested case-control study between January 2011 and December 2015. Four controls per case were matched for age, gender, address. An independent expert committee validated the diagnoses of cases and controls. Data on vaccinations were obtained from computerized vaccination records. The analyses were conducted with the use of conditional logistic regression. RESULTS: The analyses include 272 cases of ADEM and 1096 controls. No increase in the risk of ADEM was observed for vaccination against hepatitis B, influenza, polio(live), diphtheria, pertuss(acellular), tetanusis, measles, mumps, rubella, Japanese Encephalitis, meningitis, hepatitis A, varicella and rabies vaccines. Vaccine was associated with a statistically significant increase in risk in the 31-60-day exposure interval (OR, 4.04 [95% CI, 1.07-12.69]), but not the 0-30 and 61-180-day interval. There was no association between vaccine received and the recurrence of ADEM. CONCLUSIONS: Findings from the present study do not demonstrate an association of vaccines with an increased risk of ADEM and its recurrence among either paediatric (≤18â¯years) or adult (>18â¯years) individuals within the 180â¯days after vaccinations. The finding in children in the 31-60â¯day risk interval is likely coincidental and was not confirmed in separate self-control analyses.
Subject(s)
Bacterial Vaccines/administration & dosage , Bacterial Vaccines/adverse effects , Encephalomyelitis, Acute Disseminated/chemically induced , Encephalomyelitis, Acute Disseminated/epidemiology , Viral Vaccines/administration & dosage , Viral Vaccines/adverse effects , Adolescent , Adult , Aged , Aged, 80 and over , Case-Control Studies , Child , Child, Preschool , Female , Humans , Infant , Male , Middle Aged , Risk Assessment , Young AdultABSTRACT
BACKGROUND: It is important to have an estimate of the incidence of acute disseminated encephalomyelitis (ADEM) because the incidence of ADEM is unknown and the outcomes undefined in China. OBJECTIVES: This study attempts to describe ADEM incidence in large Chinese populations located in four geographically different and moderately distant areas of the same province. METHODS: A retrospective investigation was conducted with ADEM patients in Nanjing, Nantong, Yancheng and Xuzhou. The survey was carried out in regions that might have received patients meeting the case definition of ADEM provided by the International Pediatric MS Study Group from 2008 to 2011. A total of 125 hospitals were included and 412 patients were identified through the hospital information systems (HIS). RESULTS: The incidence of ADEM was 0.32/100,000/year. There are two peaks on the age-specific ADEM rates curve. One is 0.77/100,000/year among 0- to 9-year-olds, the other is 0.45/100,000/year in those aged 50-59 years. The incidence rate found for ADEM in males was 0.34/100,000/year, and in females was 0.29/100,000/year. The highest incidence rate was in Nanjing (0.40/100,000/year). CONCLUSIONS: The average annual incidence of ADEM was 0.32/100,000/year. The peak age of onset was 50-59 years old and 0-9 years old. The incidence among males was insignificantly higher than that among females. There was no significant difference in incidence by seasonal variation.
