Infectious Disease Epidemology Flashcards
Infectious disease
Caused by pathogenic microorganisms which can be spread directly or indirectly from one person to another
Medical Microbiology
The study of microorganisms that’s are of medical importance and susceptible of causing disease in human beings
Incubation period
Time between infection and presentation of symptoms
Latency
Chronic infection that is asymptomatic where the pathogen is in dormant or non replicative state
Vector born
Disease transmitted by the bite of infected arthropod species - eg Malaria
Opportunistic
Diseases which typically don’t infect humans , however when suitable situation arise they can infect us. This could be when our host defences are depleted
Disease
Disturbance in the state of health
Microbe pathway to cause a disease
- Contamination
- Adherence
- Colonisation
- Invasion
- Damage
Top 8 of Death Infections - 2016
- Respiratory Infectious
- Diarrhoeal diseases
- Tuberculosis
- HIV/AIDS
- Malaria
- Hepatitis B
- Syphilis
- Measles
Epidemiology
Study and analysis of the incidence , distribution and control of diseases
Infectious diseases : 4 case scenarios
- carrier
- No infection
- subclinical
- clinical
Subclinical can lead to carrier , immunity or non immunity
Clinical can lead to death , carrier , immunity or no immunity
Route of transmission- Direct
Skin-skin: Herpes type 1 Mucous -mucous : STIs Across placenta : toxoplasmosis Through breast milk : HIV Sneeze - cough : Influenza
Route of transmission- indirect
Food borne - Salmonella
Water borne - Hepatitis A
Vector Borne - Malaria
Air borne - Chickenpox
Timeline for infection
Dynamic of disease Infection Incubation period Symptomatic period Non diseased
Attack rate
Attack rate = ill/exposed
Epidemiologic Triad
Agent
Host Environment
Infectivity
(no.infected/no.susceptible) x 100
Pathogenicity
(no.clinical disease/ no.infected) x100
Virulence
(no.death/no.diseased)x100
Identify the microbial cause of specific disease
Microbe must be present in every case of the disease but not in healthy organisms
Microbe must be isolated from a disease host and grown in pure culture
Disease must be reproduced when a pure culture is introduced into a non-disease susceptible host
Microbe must be recoverable from an experimentally infected host
