Part Two Disease Detectives (Triads, Criteria, Chain, Prevention)

Hill's Criteria for Causation

A set of nine criteria used to establish a cause-and-effect relationship in epidemiology.

Bradford Hill

A pioneer in randomized clinical trials known for demonstrating the link between cigarette smoking and lung cancer. Also made the criteria for a causal association. (1897-1991)

Koch's Postulates

A series of criteria used to determine if a specific microbe causes a particular disease.

Limitations of Koch's Postulates

Challenges in applying Koch's Postulates due to factors like inability to culture certain pathogens and the existence of asymptomatic carriers.

Evan's Postulates

Criteria that extend Koch's Postulates to establish causal relationships in non-infectious diseases. used to establish a causal relationship between a disease and a suspected factor

Descriptive Epidemiology Triad

A framework that considers person, place, and time to describe health-related states.

Chain of Transmission Triad

A model that includes an external agent, a susceptible host, and the environment facilitating contact.

Agent

A microorganism capable of causing disease.

Reservoir

A habitat where agents can thrive and reproduce.

Portal of Exit

The route through which a pathogen leaves its host.

Mode of Transmission

The method by which a pathogen is transferred from one host or environment to another.

Portal of Entry

The route through which a pathogen enters a new host.

Susceptible Host

An individual who is vulnerable to infection due to a lack of resistance.

Disease Prevention for Bacteria

Strategies including vaccination, sanitation, hygiene, and food safety measures.

Disease Prevention for Viruses

Methods such as vaccination, vector control, respiratory precautions (masks) and good hand hygiene to prevent viral infections.

Disease Prevention for Fungi

Preventative measures like maintaining hygiene in communal areas, proper footwear, and avoiding damp environments.

Disease Prevention for Parasites

Strategies including hygiene practices, avoiding contaminated water, and deworming programs.

Disease Prevention for Prions

Precautions such as avoiding contaminated meat, screening the blood and organs of donors, and ensuring strict surgical sterilization.