Vectorial Capacity Model

Evaluate the classical vectorial capacity model m·a²·pⁿ/(−ln p) using explicit caller parameters.

Description

Vectorial capacity models the potential for a vector population to transmit infection through biting and survival during incubation.

Vectorial capacity models the potential for a vector population to transmit infection through biting and survival during incubation. It depends strongly on daily survival because the vector must live through the incubation interval.

The tool returns vectorialCapacity (vectorial capacity). Input measurements and model parameters are supplied by the caller; the tool computes the stated summary rather than acquiring those measurements.

When to use Vectorial Capacity Model

Use Vectorial Capacity Model when you already have vectorDensityPerHuman, dailyBitesPerVector, dailySurvivalFraction, extrinsicIncubationDays and want vectorialCapacity. This is useful for checking a supplied calculation, documenting a measurement convention, or comparing observations prepared on the same basis.

How to use Vectorial Capacity Model and understand its results

Enter vectorDensityPerHuman, dailyBitesPerVector, dailySurvivalFraction, extrinsicIncubationDays using the field table below. Match the units, ordering and data boundaries described in the calculation.
Run the tool after checking the stated bounds and matching paired observations or categories. A malformed request gives a tool error rather than a usable measurement.
Read vectorialCapacity. Use the calculation and interpretation below to distinguish amounts, ratios, signs and decision flags where applicable.
Review the supplied parameters and assumptions before using the result in a report or comparing it with another observation.

Input field	Meaning	Value type and bounds	Requirement
vectorDensityPerHuman	Vector density per human	number	Required
dailyBitesPerVector	Daily bites per vector	number	Required
dailySurvivalFraction	Daily survival fraction	number	Required
extrinsicIncubationDays	Extrinsic incubation days	number	Required

Multiply the vector-to-host ratio by the squared daily biting rate and incubation survival, then divide by the mortality-rate term. Daily survival must lie strictly between zero and one; the other parameters are nonnegative.

C = m × a² × p^n / (−ln p)

The symbols refer to the supplied quantities or generated values described above; unit conversions and comparison boundaries follow the stated implementation.

json

{
  "input": {
    "vectorDensityPerHuman": 10,
    "dailyBitesPerVector": 0.2,
    "dailySurvivalFraction": 0.9,
    "extrinsicIncubationDays": 10
  },
  "output": {
    "vectorialCapacity": 1.3237537342067858
  }
}

Limitations and assumptions

The caller provides all model parameters. This is a homogeneous theoretical capacity, not an estimated reproduction number or forecast of cases.

Numerical inputs must be finite. The tool checks its declared input shape and calculation constraints; those checks do not verify the quality, calibration or representativeness of the supplied observations.

Alternative or Complementary methods

Reservoir Transmission Index: Combine explicitly supplied conditional host-vector-host transmission and vector-survival fractions. Climate Envelope Screen: Screen climate observations against a caller-defined suitability envelope, not a transmission prediction.

Methodological background: Deforestation and Vectorial Capacity of Anopheles gambiae Mosquitoes in Malaria Transmission, Kenya.^[1]

References

Deforestation and Vectorial Capacity of Anopheles gambiae Mosquitoes in Malaria Transmission, Kenya — Afrane et al.; Emerging Infectious Diseases

Similar or alternative tools

Reservoir Transmission Index
Combine explicitly supplied conditional host-vector-host transmission and vector-survival fractions.
Climate Envelope Screen
Screen climate observations against a caller-defined suitability envelope, not a transmission prediction.