Prevention & Control of Disease

Major Public Health Problems:

• Communicable diseases—Waterborne, foodborne, sexually-transmitted

• Chronic illnesses—Cancer, heart disease, diabetes

• Substance abuse

• Acute injuries—Firearms, suicide, drug overdose

Chronic Illness:

• Leading cause of death and disability in U.S.

• Prevention strategies

  • Smoking cessation

  • Healthy diet

  • Exercise

  • Limiting alcohol

  • Regular screenings

  • Adequate sleep

US Top Ten Causes of Death 2019-2023:

1. Heart Disease

2. Cancer

3. Unintentional Injuries

4. Stroke

5. Chronic Lower Respiratory Diseases

6. Alzheimer’s Diseases

7. Diabetes

8. Kidney Disease

9. Chronic Liver Disease and Cirrhosis

10. COVID

Obesity (Children & Adolescents):

• Childhood obesity is a major concern

• Increases risk for chronic disease later in life

Diabetes & Prevention:

• Millions of Americans have diabetes or prediabetes

• Risk factors:

  • Overweight

  • Age >45

  • Physical inactivity

• Lifestyle changes can reduce risk by over 50%

Communicable Diseases:

• Diseases that can be spread between people

• Examples:

  • Chicken pox

  • Measles

  • Diphtheria

  • Influenza

  • Whooping cough

  • Pertussis

  • SARS

Sexually Transmitted Diseases:

• Increasing public health problem

• Most common age for 50% of disease occurs in 15 – 24 yr and racial and ethnic minorities.

• Higher risk in:

  • Adolescents

  • Women

  • Racial/ethnic minorities

• Complications include PID

• Antibiotic resistance makes treatment harder

Agent:

• Agent = cause of disease

• Communicability: how easily it spreads

• Pathogenicity: ability to cause disease

• Virulence: how severe the disease is

• Properties like antibiotic resistance and toxins increase virulence

Host:

• Host = person infected

• Defense mechanisms:

  • Skin barrier

  • Immunity

  • Herd immunity

Risk Factors for Host Susceptibility:

• Higher risk if:

  • Weak immune system

  • Very young or elderly

  • Poor nutrition

  • Genetics

  • Environmental exposure

Modes of Transmission:

• Direct: person to person (HIV, cold)

• Indirect: through vectors or objects (Lyme, TB)

Modes of Transmission Examples:

• Mechanical vectors carry germs on body

• Biological vectors become infected and transmit disease

Chain of Infection:

• Model used to stop disease spread

• Involves:

  • Agent

  • Transmission

  • Host

Chain of Infection:

• Infectious agent → Reservoir → Portal of exit → Mod of transmission → Portal of entry → Susceptible host

• Breaking one link can stop infection

Communicable vs Infectious:

• Infectious: caused by a pathogen (bacteria, viruses, protozoa, fungi, parasitic worms)

• Communicable: can spread person-to-person

• CDC has a reporting system for these diseases

Are all infectious diseases communicable?

• Answer: False

• Not all infectious diseases are communicable

Waterborne Illness:

• U.S. water is usually safe

• Can become unsafe with pipe damage

• Examples:

  • Swimmer’s ear

  • Legionnaire’s (pulmonary disease)

  • Norovirus (GI bug)

  • Giardia (parasite)

Foodborne Illness:

• “Food poisoning”

• Over 250 illnesses identified

• Examples:

  • Norovirus

  • Salmonella

  • E.coli

• Prevention:

  • Proper cooking

  • Clean food handling

• High risk:

  • Kids, elderly, pregnant, immunocompromised

Zoonotic Illness:

• Spread between animals and humans

• Spread through:

  • Contact

  • Food/water

  • Vectors (carried by organisms to humans and animals)

• Examples:

  • West Nile (mosquito)

  • Plague (flees on rats)

  • Zoonotic flu

Vector Illness:

• Vector = living carrier

• Examples:

  • Ticks

  • Mosquitoes

  • Fleas

Drug Overdose:

• Often involves opioids

• Risk factors:

  • Substance use history

  • Mental illness

  • Chronic pain

  • Negative life events

• Prevention:

  • Naloxone

  • Education

  • MAT (Medication Assisted Treatment)

  • Syringe programs

  • Immunity laws

Mental Health:

• Introduces mental health as a public health issue

• 1 out of 6 people are struggling with a mental health issue

Suicide:

• 10th leading cause of death

• 2nd for teens & young adults

• Prevention strategies:

  • Economic support

  • Safe environments

  • Social connection

  • Access to mental health care

Gun Violence:

• Major public health concern

• Linked to injury and death rates