Epidemiology studies the distribution and determinants of health and disease in populations. It provides the evidence used to detect outbreaks, estimate burden and evaluate interventions. Health Nexus stewards this page for the Nexus Consortium.
GCRI · Institution · service level R0
Epidemiology studies the distribution and determinants of health and disease in populations. Epidemiological evidence informs preparedness, resource allocation and the economic consequences of disease. In the Nexus Consortium, Health Nexus stewards its canonical page, and 2 other platforms apply it, including Biotechnology and Biosecurity as well as Health and Biosecurity Governance.
How far each division sits from a large city, with the roads and airports that carry patients and supplies, shown for the Philippines as an example geography for this subject.
cohort and case-control studies; disease surveillance; transmission modelling; outbreak investigation; burden of disease estimation; spatial epidemiology.
notifiable disease reporting systems; hospital and laboratory records; household and health surveys; vital registration; genomic surveillance.
Findings are checked through replication, sensitivity analyses and comparison of independent surveillance streams. Transmission models are assessed by out-of-sample forecasting of case counts.
Reporting delays, under-ascertainment and confounding bias estimates. Behaviour change during outbreaks alters the parameters models rely on.
Epidemiological evidence informs preparedness, resource allocation and the economic consequences of disease. It shows how health shocks interact with travel, labour, supply chains and public finance.
| Reference | What it sets |
|---|---|
| International Health Regulations (2005) | Surveillance and notification duties of states |
| EQUATOR guidelines (STROBE, CONSORT) | Reporting standards for observational studies and trials |
| GRADE | Rating certainty of evidence for recommendations |
| WHO Global Influenza Surveillance and Response System | Laboratory network for influenza surveillance |
Epidemic models are among the most visible models in public decisions, and their outputs are used far outside epidemiology: school closures, supply-chain planning, economic support. Systemic use needs explicit links to behaviour, health-system capacity and economic activity, each of which feeds back on transmission.
Health Nexus stewards epidemiology and public health science: it keeps this description current and reviews how the method is applied across the platforms.
Each term as this page uses it. Where a standard-setting body defines the term, the wording follows that body.
| Term | Definition |
|---|---|
| Public health surveillance | The continuous, systematic collection, analysis and interpretation of health data to plan and evaluate public health action. |
| Reporting delay | The time between disease onset or diagnosis and its appearance in surveillance data. |
| Sentinel surveillance | Surveillance through selected sites that report in detail, used to track trends rather than count every case. |
| Reproduction number | The average number of secondary infections caused by one infected person in a given population. |
The bodies and documents this page is read against. Status and editions change; each link goes to the issuing body.
The current service level is R0: information and enquiries. An enquiry receives a reference and names the next step; applications, payments, compute allocations and registrations open only when their team, terms and review capacity exist.