Guillain-Barré syndrome following the 2009 pandemic monovalent and seasonal trivalent influenza vaccination campaigns in Spain from 2009 to 2011: outcomes from active surveillance by a neurologist network, and records from a country-wide hospital discharge database.

Alcalde-Cabero, EnriqueAlmazán-Isla, JavierGarcía López, Fernando JAra-Callizo, José RamónAvellanal, FuencislaCasasnovas, CarlosCemillán, CarlosCuadrado, José IgnacioDuarte, JacintoFernández-Pérez, María DoloresFernández, ÓscarGarcía Merino, Juan AntonioGarcía Montero, RosaMontero, DoloresPardo, JulioRodríguez-Rivera, Francisco JavierRuiz-Tovar, Maríade Pedro-Cuesta, Jesús2016-08-042016-08-042016-05-21Alcalde-Cabero E, Almazán-Isla J, García López FJ, Ara-Callizo JR, Avellanal F, Casasnovas C, et al. Guillain-Barré syndrome following the 2009 pandemic monovalent and seasonal trivalent influenza vaccination campaigns in Spain from 2009 to 2011: outcomes from active surveillance by a neurologist network, and records from a country-wide hospital discharge database. BMC Neurol. 2016; 16(1):75http://hdl.handle.net/10668/2292Journal Article;BACKGROUND Studies have shown a slight excess risk in Guillain-Barré syndrome (GBS) incidence associated with A(H1N1)pdm09 vaccination campaign and seasonal trivalent influenza vaccine immunisations in 2009-2010. We aimed to assess the incidence of GBS as a potential adverse effect of A(H1N1)pdm09 vaccination. METHODS A neurologist-led network, active at the neurology departments of ten general hospitals serving an adult population of 4.68 million, conducted GBS surveillance in Spain in 2009-2011. The network, established in 1996, carried out a retrospective and a prospective study to estimate monthly alarm thresholds in GBS incidence and tested them in 1998-1999 in a pilot study. Such incidence thresholds additionally to observation of GBS cases with immunisation antecedent in the 42 days prior to clinical onset were taken as alarm signals for 2009-2011, since November 2009 onwards. For purpose of surveillance, in 2009 we updated both the available centres and the populations served by the network. We also did a retrospective countrywide review of hospital-discharged patients having ICD-9-CM code 357.0 (acute infective polyneuritis) as their principal diagnosis from January 2009 to December 2011. RESULTS Among 141 confirmed of 148 notified cases of GBS or Miller-Fisher syndrome, Brighton 1-2 criteria in 96 %, not a single patient was identified with clinical onset during the 42-day time interval following A(H1N1)pdm09 vaccination. In contrast, seven cases were seen during a similar period after seasonal campaigns. Monthly incidence figures did not, however, exceed the upper 95 % CI limit of expected incidence. A retrospective countrywide review of the registry of hospital-discharged patients having ICD-9-CM code 357.0 (acute infective polyneuritis) as their principal diagnosis did not suggest higher admission rates in critical months across the period December 2009-February 2010. CONCLUSIONS Despite limited power and underlying reporting bias in 2010-2011, an increase in GBS incidence over background GBS, associated with A(H1N1)pdm09 monovalent or trivalent influenza immunisations, appears unlikely.enGuillain-Barré syndromeInfluenza A virus H1N1 subtypeInfluenza vaccinesPublic health surveillanceSafetyICD-9-CMSíndrome de Guillain-BarréHospitales generalesInmunizaciónIncidenciaSubtipo H1N1 del virus de la influenza AVacunas contra la influenzaGripe HumanaClasificación internacional de enfermedadesSíndrome de Miller FisherNeuritisProyectos pilotoEstudios prospectivosSistema de registrosEstudios retrospectivosRiesgoEstaciones del añoEspañaVacunaciónMedical Subject Headings::Diseases::Nervous System Diseases::Autoimmune Diseases of the Nervous System::Polyradiculoneuropathy::Guillain-Barre SyndromeMedical Subject Headings::Health Care::Health Care Facilities, Manpower, and Services::Health Facilities::Hospitals::Hospitals, GeneralMedical Subject Headings::Named Groups::Persons::Age Groups::AdultMedical Subject Headings::Organisms::Eukaryota::Animals::Chordata::Vertebrates::Mammals::Primates::Haplorhini::Catarrhini::Hominidae::HumansMedical Subject Headings::Analytical, Diagnostic and Therapeutic Techniques and Equipment::Therapeutics::Biological Therapy::Immunomodulation::Immunotherapy::ImmunizationMedical Subject Headings::Analytical, Diagnostic and Therapeutic Techniques and Equipment::Investigative Techniques::Epidemiologic Methods::Data Collection::Vital Statistics::Morbidity::IncidenceMedical Subject Headings::Organisms::Viruses::RNA Viruses::Orthomyxoviridae::Influenzavirus A::Influenza A virus::Influenza A Virus, H1N1 SubtypeMedical Subject Headings::Chemicals and Drugs::Complex Mixtures::Biological Agents::Vaccines::Viral Vaccines::Influenza VaccinesMedical Subject Headings::Diseases::Virus Diseases::RNA Virus Infections::Orthomyxoviridae Infections::Influenza, HumanMedical Subject Headings::Information Science::Information Science::Information Services::Documentation::Vocabulary, Controlled::International Classification of DiseasesMedical Subject Headings::Diseases::Nervous System Diseases::Central Nervous System Diseases::Brain Diseases::Cerebellar Diseases::Miller Fisher SyndromeMedical Subject Headings::Diseases::Nervous System Diseases::Neuromuscular Diseases::Peripheral Nervous System Diseases::NeuritisMedical Subject Headings::Disciplines and Occupations::Health Occupations::Medicine::NeurologyMedical Subject Headings::Analytical, Diagnostic and Therapeutic Techniques and Equipment::Investigative Techniques::Epidemiologic Methods::Epidemiologic Study Characteristics as Topic::Pilot ProjectsMedical Subject Headings::Analytical, Diagnostic and Therapeutic Techniques and Equipment::Investigative Techniques::Epidemiologic Methods::Data Collection::RegistriesMedical Subject Headings::Analytical, Diagnostic and Therapeutic Techniques and Equipment::Investigative Techniques::Epidemiologic Methods::Epidemiologic Study Characteristics as Topic::Epidemiologic Studies::Case-Control Studies::Retrospective StudiesMedical Subject Headings::Phenomena and Processes::Mathematical Concepts::Probability::RiskMedical Subject Headings::Phenomena and Processes::Physical Phenomena::Time::Periodicity::SeasonsMedical Subject Headings::Geographicals::Geographic Locations::Europe::SpainMedical Subject Headings::Analytical, Diagnostic and Therapeutic Techniques and Equipment::Therapeutics::Biological Therapy::Immunomodulation::Immunotherapy::Immunization::Immunotherapy, Active::VaccinationGuillain-Barré syndrome following the 2009 pandemic monovalent and seasonal trivalent influenza vaccination campaigns in Spain from 2009 to 2011: outcomes from active surveillance by a neurologist network, and records from a country-wide hospital discharge database.research article27206524open access10.1186/s12883-016-0598-z1471-2377PMC4875759