epidemiology part 2

host

host

goes through chain of events leading from inapparent infection to a clinical case of the disease

end result of infection

• complete recovery

• permanent disability

• death

• chronicity

non-specific defense mechanism

• skin- physical barrier

• mucosal surface

• tears

• saliva

• acid pH of gastric juice

• age, nutrition status, genetic factors

necessary cause

Factor must be present for the disease to occur

sufficient cause

Cause that inevitably initiates or produce an effect

necessary cause

it must invariably precede an effect

sufficient cause

includes “component causes”

necessary and sufficient

without the factor, disease never develops. With the factor, disease always develops

necessary but not sufficient

the factor in and of itself is not enough to cause disease

sufficient but not necessary

the factor alone can cause disease, but so can other factors in its absence

neither sufficient nor necessary

the factor cannot cause disease on its own, nor is it the only factor that can cause that disease

neither sufficient nor necessary

This is the probable model for chronic disease relationships

herd immunity

resistance of a group to invasion and spread of an infectious agent based on the immunity of a high proportion of individual members of the group

herd immunity

immunity of a group or a community

prepathogenesis

phase before man is involved

pathogenesis

Includes the success invasion and establishment of the agent in the host

prepathogenesis

through interaction of agent, host and environmental factors, agent finally reaches man

pathogenesis

From incubation period to production of detectable evidence of the disease process (Clinical Horizon), until it is interrupted by treatment

stage of susceptibility

During this stage, the individual in the population does not have the disease nor the infection; only the risk factors are present

risk factors

• poor health and nutrition

• lack of immunity

• behaviors that increase opportunity for exposure

adaptation

immediate response of the body, immune system

stage of presymptomatic disease (subclinical stage)

In this stage there is no manifest of disease but pathogenic changes have started to occur

stage of presymptomatic disease (subclinical stage)

The etiological factors are present in the body and are causing pathological changes, but there are not yet any discernible signs or symptoms

incubation period

time between exposure to onset of symptoms

latency period

time between exposure to causal factor and disease detection

incubation period

infectious diseases

latency period

common in non-communicable diseases

saxitoxin and similar toxins from shellfish

few minutes-30 mins

organophosphorus ingestion

few minutes-few hours

salmonella

6-48 hours

SARS

3-10 days, usually 4-6 days

stage of clinical disease

refers to the period of time at the onset of signs or symptoms of the disease.

stage of clinical disease

The outcomes of this stage may be recovery, disability or death.

stage of clinical disease

It is important to subdivide this stage for better management of cases and for purposes of epidemiologic study

stage of disability

Any temporary or long term reduction of a person’s activities

primordial prevention

prevent development of risk factors

primary prevention

reduction of risk factors

primary prevention

immunization

primary prevention

removal of harmful agents

secondary prevention

early detection

secondary prevention

prompt treatment

secondary prevention

cure disease at the earliest age

tertiary prevention

complete treatment

tertiary prevention

limit disability

tertiary prevention

rehabilitation

classification of diseases

method of grouping of diseases based on their specific features

classification of diseases

ensures universal criteria for diagnosing diseases

primary data

collected by the researcher firsthand

secondary data

derived from another source that may have other objectives for collecting the data

civil registry

Major and most effective source of vital statistics

birth statistics

most visible evidence of a government’s existence of a person as a member of the society

immediate cause of death

final disease, injury, complication

antecedent cause of death

intervening event between immediate and underlying cause of death

underlying cause of death

disease that initiated chain of morbid events

Republic Act 10173

Data Privacy Act of 2012

Executive Order No. 2 s. 2016

Freedom of Information

data sharing

voluntary release of information by one investigator or institution to another for purposes of scientific research

data linkage

joining data from two or more sources