An illness caused by some specific biological agent or its toxic products that can be transmitted from an infected person, animal, or inanimate reservoir to a susceptible host
Noncommunicable (noninfectious) disease
A disease that cannot be transmitted from infected host to susceptible host
Examples of Communicable Diseases
Common cold
Pneumonia
Mumps
Measles
Pertussis
Typhoid fever
Cholera
Examples of Noncommunicable Diseases
Appendicitis
Poisoning
Injury (due to motor vehicle crash, fire, gunshot, etc.)
Acute disease
An illness with peak severity of symptoms occurs and subsides within 3 months (usually sooner)
Chronic disease
A disease in which symptoms continue longer than 3 months and, in some cases, for the remainder of one's life
Examples of Communicable Chronic Diseases
AIDS
Lyme disease
Tuberculosis
Syphilis
Rheumatic fever following streptococcal infections
Hepatitis B
Examples of Noncommunicable Chronic Diseases
Diabetes
Coronary heart disease
Osteoarthritis
Cirrhosis of the liver due to alcoholism
Reservoir
The source from which an infectious agent is transmitted to a susceptible host
Types of Reservoirs
Human
Animal
Environmental (plants, soil, water)
Chain of infection
A model to conceptualize the transmission of a communicable disease from its source to a susceptible host
Case
A person who is sick with a disease
Carrier
A person or animal that harbors a specific communicable agent in the absence of discernible clinical disease and serves as a potential source of infection to others
Zoonosis
A communicable disease transmissible under natural conditions from vertebrate animals to humans
Anthroponosis
A disease that infects only humans
Direct transmission
The immediate transfer of an infectious agent by direct contact between infected and susceptible individuals
Indirect transmission
Transmission of communicable disease involving an intermediate site
Prevention
The planning for and taking of action to forestall the onset of a disease or other health problem
Intervention
Efforts to control a disease in progress
Eradication
The complete elimination or uprooting of a disease (e.g., smallpox eradication)
Levels of Prevention
Primary prevention
Secondary prevention
Tertiary prevention
Primary prevention
Preventive measures that preempt the onset of illness or injury during the prepathogenesis period
Secondary prevention
Preventive measures that lead to an early diagnosis and prompt treatment of a disease or injury to limit disability and prevent more severe pathogenesis
Tertiary prevention
Measures aimed at rehabilitation following significant pathogenesis
Factors to understand the spread of a communicable disease
Symptoms
Causative agent/s
Diagnosis
Occurrence
Reservoir
Incubation period
Transmission
Risk groups
Prevention
Management of the patient
Management of Contacts & the immediate environment
Noncommunicable Diseases (NCDs)
Remain a concern for communities, are leading causes of death, can occur in epidemic proportions, have the potential to deplete resources rapidly, have a multi-causation disease model
Multi-causation disease model
The human host is in the center of a complex environment in which he or she lives, the host has a unique genetic endowment, a multitude of risk factors within the environment may contribute to the disease process
Modifiable Risk Factors
Body weight
Salt intake
Smoking
Exercise
Non-Modifiable Risk Factors
Age
Ethnicity
Sex
Genetics
Contributing Risk Factors
Enhances the development and effects of the disease and its complications, includes low socioeconomic status, psychological risk factors, breakdown of social structure
Four Major Categories of NCDs
Cardiovascular Diseases
Diabetes
Chronic Respiratory Diseases
Cancer
Coronary Heart Disease (CHD)
A chronic disease characterized by damage to the coronary arteries in the heart, evolves from the condition known as atherosclerosis - narrowing of the blood vessels due to fat build-up along the walls of arteries
Screening
A type of secondary prevention, the goal is early detection of the disease to permit early intervention, positive results may require more specific diagnostic procedures
NCD Best Buys
Evidenced-based, cost-effective public health interventions to stop and control NCDs, serves as a guide for policy decisions to address the four main diseases and their underlying risk factors