Case fatality rate

Attack rate

Proportion of clinically apparent infection

Lab tests

Parasite

Virus

Toxic product

Fungus

Pathogenicity is a qualitative measure of whether a microorganism can cause disease, while virulence is a quantitative measure of disease severity

Pathogenicity measures how easily a disease spreads, while virulence refers to its ability to evade the immune system

Pathogenicity and virulence are interchangeable terms that both describe the ability of a microorganism to cause disease

Pathogenicity refers to the severity of a disease, while virulence determines whether an organism can cause disease

Susceptible Host → Mode of Transmission → Portal

of Entry → Infectious Agent → Reservoir → Portal of Exit

Portal of Exit → Infectious Agent → Reservoir →

Susceptible Host → Mode of Transmission → Portal of Entry

Mode of Transmission → Reservoir → Infectious

Agent → Portal of Exit → Susceptible Host → Portal of Entry

Infectious Agent → Reservoir → Portal of Exit →

Mode of Transmission → Portal of Entry → Susceptible Host

The respiratory tract serves as an exit point for all pathogens from their host

Bloodborne pathogens only leave the host when

they get ingested by blood-sucking arthropods

A number of pathogens leave the host body through

urine or feces and through skin lesions

The exit point for a pathogen in a host body

never matches its entry point

Planetary

health focus on the health of human civilization and the natural systems on

which it depends, whereas, public health focus on protecting and improving

health of people and communities

Planetary health aims to improve health and achieve equity in health

for all people worldwide, whereas public health focus on protecting and

improving health of people and communities

Planetary health refers to an integrated approach that aims to sustainably balance and optimise the health of people, animals, and ecosystems,

whereas public health focus on improving health and achieving health equity for

all people worldwide

Planetary health focuses on the health of human civilization and the

natural systems on which it depends, whereas public health recognise that the

health of humans and ecosystems are closely linked and independent