Prevention of infectious and parasitic diseases

Dr. Wasantha Gunathunga

Department of Community Medicine

Levels of prevention

Primary

Secondary

Tertiary

H- nutr, immH- nutr, imm

Primary prevention

Host Environment agent Eg. tuberculosis

Host

Age Sex Poor nutrition Habits HIV Immunity - BCG

Host

Age Sex Poor nutrition Habits HIV Immunity - BCG

Age : Old age (eg. TB) Infancy(eg.diarrhoea) Reproductive age (HIV) Sex: Male female

Host

Age Sex Poor nutrition Habits HIV Immunity - BCG

Poor nutrition Proper infant and child

feeding Nutrition during illness Nutrition in special

groups Proper feeding of senior

citizens

Host

Age Sex Poor nutrition Habits HIV Immunity - BCG

Habits Prevention of substance

abuse Prevention of risk sexual

behaviour Hygiene Other

Host

Age Sex Poor nutrition Habits HIV Immunity - BCG

Prevention of HIV will prevent many other infections

Immunity –by vaccinations

Agent

Prevent drug resistance -Tubercle bacillus

Not giving opportunity

Look for new forms – mutations, eg. SARS

Environment

Manage overcrowding Recognize occupational

exposure Improve domestic

ventilation public transport Prevent antibiotic

residues in food Treat open cases

secondary prevention

Surveillance Screening Complete treatment Defaulter tracing

Surveillance

Epidemiological surveillance is the continuous scrutiny of factors that determine the occurrence and distribution of diseases or other conditions of ill health. It includes systematic collection, analysis, interpretation and distribution of relevant data for action.

Approaches of prevention

Population approach

High risk approach

Control

Elimination

Eradication

Disease Control

The disease ‘agent is allowed to persist in the environment

The disease ceases to become a public health problem

A state of equilibrium Disease control involves activities of primary

prevention and secondary prevention

Elimination

Interruption of disease transmission in the community

e.g. Diphtheria

Eradication

Total removal of the infective agent thereby terminating disease transmission and the possibility of disease transmission

e.g. Small pox , ?polio

Controlling the reservoir of infection

The aim is to reduce the quantity of the agent available for dissemination

1. Early Diagnosis2. Notification3. Epidemiological investigation4. Isolation5. Treatment6. Quarantine