Related Experiment Video

Updated: Jun 20, 2026

Noninvasive Sampling of Mucosal Lining Fluid for the Quantification of In Vivo Upper Airway Immune-mediator Levels
05:31

Noninvasive Sampling of Mucosal Lining Fluid for the Quantification of In Vivo Upper Airway Immune-mediator Levels

Published on: August 7, 2017

Seasonality and comparative dynamics of six childhood infections in pre-vaccination Copenhagen

C Jessica E Metcalf1, Ottar N Bjørnstad, Bryan T Grenfell

  • 1Centre for Infectious Disease Dynamics, The Pennsylvania State University, 208 Mueller Laboratory, University Park, PA 16802, USA. cjm53@psu.edu

Proceedings. Biological Sciences
|September 11, 2009
PubMed

Insights

School holidays impact childhood infection seasonality, but term-time forcing isn't the sole driver for all diseases. Waning immunity and late summer surges in bacterial infections also play significant roles.

Area of Science:

  • Epidemiology
  • Infectious Disease Dynamics
  • Public Health

Background:

  • Seasonal variation significantly influences the epidemic dynamics of acute infections.
  • Measles, a well-understood childhood infection, is often perceived to be driven by school terms in developed countries.
  • The extent to which school terms drive seasonality in other childhood infections is not well-established.

Purpose of the Study:

  • To investigate seasonal transmission patterns of six childhood infections, including measles.
  • To determine the role of school terms versus other factors in driving infection seasonality.
  • To analyze the relationship between the mean age of infection and school enrollment ages.

Main Methods:

  • Utilized a unique long-term dataset tracking weekly incidence of six infections.
  • Analyzed age-incidence data to calculate the mean age of infection for each disease.
  • Compared seasonal transmission patterns with school holiday schedules and theoretical predictions.

Main Results:

  • Observed correlations between reduced transmission and school holidays for some infections, but also noted discrepancies.
  • Found that the average age of infection closely matched school enrollment ages, yet seasonality drivers were complex.
  • Theoretical models predicting seasonality amplitude based on basic reproductive rate and term-time forcing were not consistently supported.
  • Identified a significant late summer transmission increase for pertussis, scarlet fever, and diphtheria, preceding school vacations.

Conclusions:

  • Seasonal patterns in childhood infections are unlikely to be solely driven by school terms, especially when susceptible populations fluctuate due to factors like waning immunity.
  • Other drivers, including late summer transmission surges in bacterial infections, contribute to the overall seasonality of disease spread.

More Related Videos

Standardization of Transfer across Labs between Flow Cytometers for Detection of Lymphocytes in Japanese Encephalitis Vaccinated Children06:22

Standardization of Transfer across Labs between Flow Cytometers for Detection of Lymphocytes in Japanese Encephalitis Vaccinated Children

Published on: February 10, 2023

Related Concept Videos

Infectious Diseases and Their Occurrence01:28

Infectious Diseases and Their Occurrence

Infectious diseases appear in populations through various transmission patterns, influenced by pathogen characteristics, population immunity, environmental conditions, and social behavior. Understanding these patterns is essential for effective public health surveillance and intervention. These categories—sporadic, outbreak, epidemic, pandemic, and endemic—help frame the nature and scope of disease events.Sporadic diseases occur irregularly and infrequently, without a predictable temporal or...
Vaccinations01:51

Vaccinations

Overview
Principles of Disease Surveillance01:26

Principles of Disease Surveillance

Disease surveillance is the systematic collection, analysis, and interpretation of health data essential to the planning, implementation, and evaluation of public health practice. This process integrates data dissemination to entities responsible for preventing and controlling disease, injury, and disability. Surveillance systems provide crucial information for action, helping public health authorities make informed decisions to manage and prevent outbreaks, ensure public safety, optimize...
Smallpox01:24

Smallpox

Smallpox is a severe contagious disease caused by the Variola major virus, a double-stranded DNA member of the Poxviridae family.Variola major transmission occurs primarily via inhalation of virus-laden droplets or direct contact with infectious scabs. The incubation period averages approximately seven days, although it may range from 7 to 17 days depending on the inoculum and host factors.Clinically, the prodromal phase is marked by an abrupt onset of high fever, malaise, headache, and myalgia.
Influenza01:27

Influenza

Influenza is an acute, highly communicable viral disease that affects the respiratory tract and is responsible for seasonal epidemics worldwide. Influenza A is the most prevalent type associated with widespread outbreaks and is subtyped based on two surface glycoproteins: hemagglutinin (H) and neuraminidase (N), as in H1N1. These glycoproteins are essential for viral infectivity, transmission, and immune recognition. Transmission occurs primarily through respiratory droplets and contaminated...
Causality in Epidemiology01:21

Causality in Epidemiology

Causality or causation is a fundamental concept in epidemiology, vital for understanding the relationships between various factors and health outcomes. Despite its importance, there's no single, universally accepted definition of causality within the discipline. Drawing from a systematic review, causality in epidemiology encompasses several definitions, including production, necessary and sufficient, sufficient-component, counterfactual, and probabilistic models. Each has its strengths and...