Choosing Public Health Interventions

By Dr. Jay K. Varma
Physician, Epidemiologist, and Public Health Expert

 🎯 Once You Know the Problem, What Do You Do About It?

After identifying the source and scope of an outbreak, the next question becomes:

What intervention will reduce the number of people getting sick? We also refer to this as reducing the force of infection (FOI). 

In public health, interventions range from societal-level policies to individual actions, and choosing the right one requires both evidence and judgment.

🧱 The Hierarchy of Public Health Impact

A useful way to think about intervention choices is the “health impact pyramid,” developed by former CDC Director Dr. Tom Frieden. The pyramid ranks strategies from most impactful (at the base) to least impactful (at the top):

1. Addressing socioeconomic factors

   • Examples: reducing poverty, racism, ensuring access to healthcare

2. Changing the environment to make healthy choices the default

   • Examples: water fluoridation, food safety inspections, safe housing

3. Long-lasting protective interventions

   • Examples: vaccines, contraceptives, clean needles

4. Clinical interventions

   • Examples: medications to prevent or treat disease (e.g., antivirals, antibiotics)

5. Counseling and education

   • Examples: telling people to wear masks, wash hands, avoid risky settings

The most effective interventions don’t require individual behavior change—they make the healthy choice the default or automatic.

🧪 Evidence-Based Decision-Making

Not all interventions are created equal. To choose the right one, public health officials must ask:

• Does it work?
  → Is there high-quality evidence (from trials or studies) that the intervention reduces illness or death?

• Is it feasible?
  → Do we have the people, materials, and systems in place to implement it?

• Is it acceptable?
  → Will the community or individuals agree to it? Will there be resistance?

• Do the benefits outweigh the harms?
  → Every intervention has side effects or costs—are they justified?

• Can we afford it?
  → Do we have the funding or resources to deploy it at scale?

• Does it align with our values?
  → Is the action consistent with our legal, cultural, or ethical principles?

💬 Real-World Examples

• Vaccination programs
  → High-impact, long-lasting, but sometimes politically or socially contested

• Isolation and quarantine
  → Effective but may raise legal and ethical concerns

• Taxing sugary beverages or tobacco
  → Can reduce consumption, but may be opposed by industry or certain communities

• Public education campaigns
  → Often the most visible response, but least effective when used alone

⚠️ Missteps to Avoid

• Acting based on public pressure rather than science

• Choosing interventions that are too narrow or too broad

• Ignoring feasibility, cost, or unintended consequences

• Implementing without evaluating results

🧠 Bottom Line

Selecting the right intervention is as much a strategic decision as it is a scientific one. It requires:

• Evidence

• Community insight

• Political will

• Clear communication

Public health is not just about knowing what to do—it’s about doing what’s possible and effective.

🔗 Learn More

• 📖 Health Impact Pyramid

• 📖 How Do We Decide What Was “Too Much” During COVID-19 Response”

• 📖 Skills Public Health Officials Needs for Next Pandemic