Calculate the herd immunity threshold HIT = 1 − 1/R₀ from the SIR model. Shows the fraction of the population that must be immune to halt epidemic spread and prevent future outbreaks.
| Constant | Symbol | Value |
|---|---|---|
| Speed of light | c | 2.99792458×10⁸ |
| Planck's constant | h | 6.62607015×10⁻³‴ |
| Boltzmann constant | kʙ | 1.380649×10⁻²³ |
| Avogadro's number | Nₐ | 6.02214076×10²³ |
| Gravitational constant | G | 6.6743×10⁻¹¹ |
| Gas constant | R | 8.31446 |
| Elementary charge | e | 1.602176634×10⁻¹⁹ |
| Electron mass | mₑ | 9.1093837015×10⁻³¹ |
| Proton mass | mₚ | 1.67262192369×10⁻²⁷ |
| Fine-structure constant | α | 7.2973525693×10⁻³ |
Calculate the herd immunity threshold HIT = 1 − 1/R₀ from the SIR model. Shows the fraction of the population that must be immune to halt epidemic spread and prevent future outbreaks
Each component has a specific meaning:
Note: Interpret the sir herd immunity result against the clinical thresholds and context described above.
Enter the SIR model for the patient or scenario you are assessing. Calculate the herd immunity threshold HIT = 1 − 1/R₀ from the SIR model. Shows the fraction of the population that must be immune to halt epidemic spread and prevent future outbreaks. Use the sir herd immunity result to inform your clinical assessment.