Biomaterial Database

Effective case/infection ratio of poliomyelitis in vaccinated populations. 2016

G Bencskó, and T Ferenci

Polymer Chemistry Research Group,Institute of Materials and Environmental Chemistry,Research Centre for Natural Sciences,Hungarian Academy of Sciences,Budapest,Hungary.

Recent polio outbreaks in Syria and Ukraine, and isolation of poliovirus from asymptomatic carriers in Israel have raised concerns that polio might endanger Europe. We devised a model to calculate the time needed to detect the first case should the disease be imported into Europe, taking the effect of vaccine coverage - both from inactivated and oral polio vaccines, also considering their differences - on the length of silent transmission into account by deriving an 'effective' case/infection ratio that is applicable for vaccinated populations. Using vaccine coverage data and the newly developed model, the relationship between this ratio and vaccine coverage is derived theoretically and is also numerically determined for European countries. This shows that unnoticed transmission is longer for countries with higher vaccine coverage and a higher proportion of IPV-vaccinated individuals among those vaccinated. Assuming borderline transmission (R = 1·1), the expected time to detect the first case is between 326 days and 512 days in different countries, with the number of infected individuals between 235 and 1439. Imperfect surveillance further increases these numbers, especially the number of infected until detection. While longer silent transmission does not increase the number of clinical diseases, it can make the application of traditional outbreak response methods more complicated, among others.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D011051	Poliomyelitis	An acute infectious disease of humans, particularly children, caused by any of three serotypes of human poliovirus (POLIOVIRUS). Usually the infection is limited to the gastrointestinal tract and nasopharynx, and is often asymptomatic. The central nervous system, primarily the spinal cord, may be affected, leading to rapidly progressive paralysis, coarse FASCICULATION and hyporeflexia. Motor neurons are primarily affected. Encephalitis may also occur. The virus replicates in the nervous system, and may cause significant neuronal loss, most notably in the spinal cord. A rare related condition, nonpoliovirus poliomyelitis, may result from infections with nonpoliovirus enteroviruses. (From Adams et al., Principles of Neurology, 6th ed, pp764-5)	Infantile Paralysis,Polio,Poliomyelitis, Nonpoliovirus,Poliomyelitis, Preparalytic,Encephalitis, Polio,Epidemic Acute Poliomyelitis,Polio Encephalitis,Poliomyelitis Infection,Poliomyelitis, Acute,Acute Poliomyelitis,Acute Poliomyelitis, Epidemic,Infection, Poliomyelitis,Infections, Poliomyelitis,Nonpoliovirus Poliomyelitis,Paralysis, Infantile,Poliomyelitides, Preparalytic,Poliomyelitis Infections,Poliomyelitis, Epidemic Acute,Polios,Preparalytic Poliomyelitis
D004812	Epidemiologic Methods	Research techniques that focus on study designs and data gathering methods in human and animal populations.	Epidemiologic Method,Epidemiological Methods,Methods, Epidemiologic,Epidemiological Method,Method, Epidemiologic,Method, Epidemiological,Methods, Epidemiological
D005060	Europe	The continent north of AFRICA, west of ASIA and east of the ATLANTIC OCEAN.	Northern Europe,Southern Europe,Western Europe
D005260	Female		Females
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D013997	Time Factors	Elements of limited time intervals, contributing to particular results or situations.	Time Series,Factor, Time,Time Factor
D014611	Vaccination	Administration of vaccines to stimulate the host's immune response. This includes any preparation intended for active immunological prophylaxis.	Immunization, Active,Active Immunization,Active Immunizations,Immunizations, Active,Vaccinations
D015233	Models, Statistical	Statistical formulations or analyses which, when applied to data and found to fit the data, are then used to verify the assumptions and parameters used in the analysis. Examples of statistical models are the linear model, binomial model, polynomial model, two-parameter model, etc.	Probabilistic Models,Statistical Models,Two-Parameter Models,Model, Statistical,Models, Binomial,Models, Polynomial,Statistical Model,Binomial Model,Binomial Models,Model, Binomial,Model, Polynomial,Model, Probabilistic,Model, Two-Parameter,Models, Probabilistic,Models, Two-Parameter,Polynomial Model,Polynomial Models,Probabilistic Model,Two Parameter Models,Two-Parameter Model
D023321	Poliovirus Vaccines	Vaccines used to prevent POLIOMYELITIS. They include inactivated (POLIOVIRUS VACCINE, INACTIVATED) and oral vaccines (POLIOVIRUS VACCINE, ORAL).	Poliovirus Vaccine,Vaccine, Poliovirus,Vaccines, Poliovirus