From: How do biting disease vectors behaviourally respond to host availability?
Response type | Ecological equivalent | Parametric conditions | Vector behaviour |
---|---|---|---|
Type I | Analogous to Holling’s Type I | α = 1 β = 1 | Indiscriminate; or vector biting that is consistent (proportionate) across relative availabilities of alternative hosts. |
Type II | Analogous to Holling’s Type II | α < 1 β ≥ 1 | The HBI of an anthropophilic vector saturates whereby even when humans and non-humans have similar availability, almost all blood meals are secured from humans. |
Type III | Analogous to Holling’s Type III | α ≥ 1 β > 1 | Similar to a Type II response, the HBI saturates, but at low levels of human availability vectors are uninclined to bite them. Corresponding with the analogous Holling’s Type, this could be associated with a learned behaviour with an increased rate of human encounters. |
Type IV | Inversion of Holling’s Type II | α > 1 β ≤ 1 | A zoophilic vector is uninclined to bite humans until they constitute all but the only available blood source. |
Type V | Inversion of Holling’s Type III | α ≤ 1 β < 1 | HBI saturates and becomes relatively invariant when humans and non-human hosts are at similar availability. This is analogous to ‘negative prey switching’ whereby the ‘predator’ consumes disproportionately less of the more available ‘prey’ [41]. Eventually, when non-humans become vanishingly rare, the HBI is forced to increase sharply to unity. |