Background
Feature | Previous versions | Current version |
---|---|---|
Time step resolution | Daily | Hourly |
Host-seeking and oviposition | Anytime | Only at night |
Stage transitions | Anytime | Only during permitted time-windows |
Egg development time | Constant | Temperature-dependent; consists of egg incubation and hatching times |
Vector control interventions
Methods
The core model
Parameter | Description | Unit | Default value |
---|---|---|---|
T
| Ambient temperature | °C | 30 |
P
FindHost
| Probability of a female adult to find a human host | N/A | 25% |
P
FindBloodMeal
| Probability of a female adult to find a blood meal | N/A | 100% |
P
FindHabitat
| Probability of a female adult to find an aquatic habitat | N/A | 25% |
HC
| Habitat capacity | N/A | 1000 |
r
| Combined seasonality factor | N/A | 1.0 |
Biomass
| Age-adjusted biomass in a habitat | N/A | Dynamic |
N
Eggs
| Number of eggs in a habitat | N/A | Dynamic |
N
e
| One-day old equivalent larval population | N/A | Dynamic |
N
Pupae
| Number of pupae in a habitat | N/A | Dynamic |
Age
Cohort
| Common age of a cohort | Day | Dynamic |
N
LarvaePerCohort
| Number of larvae in an age-cohort | N/A | Dynamic |
gcn
| Gonotrophic cycle number | N/A | Dynamic |
Eggs
| Maximum number of eggs a female can lay | N/A | Dynamic |
N (170, 30)
| Normal distribution for fecundity in the first gonotrophic cycle | N/A | mean =170, sd =30 |
Eggs
Potential
| Potential number of eggs a female is allowed to lay | N/A | Dynamic |
w
| Habitat sampling weight (within the same gonotrophic cycle) | N/A | 1, 2 or 3 |
DMR | Daily mortality rate | Day-1 | 0.1 |
HMR | Hourly mortality rate | Hour-1 | 0.00438 |
α | Baseline DMR (for larvae and adults) | Day-1 | 0.1 |
β | Exponential mortality increase with age | N/A | 0.04 |
s
| Degree of mortality deceleration | N/A | 0.1 |
The aquatic phase
Egg (E)
Larva (L)
Parameter | Description | Unit/dimension | Value used |
---|---|---|---|
ρ
25°C
| Larval development rate per hour at 25°C, assuming that there is no temperature inactivation of the critical enzyme | Hour-1 | 0.037 |
R
| The universal gas constant | cal × K-1 × mol-1 | 1.987 |
The enthalpy (change) of activation of the reaction catalyzed by the enzyme | cal × K-1 × mol-1 | 15684 | |
ΔH
L
| The enthalpy change associated with low temperature inactivation of the enzyme | cal × K-1 × mol-1 | -229902 |
ΔH
H
| The enthalpy change associated with high temperature inactivation of the enzyme | cal × K-1 × mol-1 | 822285 |
The temperature where 50% of the enzyme is inactivated by low temperature | K | 286.4 | |
The temperature where 50% of the enzyme is inactivated by high temperature | K | 310.3 |
Pupa (P)
The adult phase
Immature adult (IA)
Mate seeking (MS)
Blood meal seeking (BMS)
Blood meal digesting (BMD)
Gravid (G)
Aquatic habitats
Oviposition
Mortality rates
Aquatic mortality rates
Adult mortality rates
Hypothetical vector control interventions (HVCIs)
-
L Entering : imposes a one-time killing effect when an egg enters the larva stage. Thus, it simulates a one-time hazard on an egg, essentially simulating LSM by insecticidal control;
-
L Updating : imposes an additional killing effect for a larva, and the killing effect sustains every hour (during the entire larval development stage; see Equations 2, 3, 4 and 5) until the larva enters the pupa stage or dies. Thus, L Updating simulates a continuous killing effect on a larva, essentially simulating LSM by means of biological control;
-
IA Resting : works similarly as L Updating , imposing an additional killing effect for a mosquito during every hour in the immature adult stage;
-
BMS Foraging : imposes an additional killing effect for a host seeking female mosquito in the blood meal seeking stage. The killing effect is in action whenever a female encounters a host (with P FindHost =25%, meaning 25% probability of finding a host in each hour during BMS), and continues every hour until the mosquito successfully gets a blood meal (and then enters the blood meal digesting stage) or dies; if the female fails to find a host and still survives, it will have to wait in the BMS stage until the next time step, and then repeat the host seeking process. Thus, BMS Foraging simulates a continuous killing effect on a host seeking female during the entire BMS stage, essentially simulating ITNs and LLINs;
-
BMS Foraging, K=0% : being a special case, it is similar to BMS Foraging , with the exception that it has no killing effectiveness. Thus, it simulates a continuous effect (with no additional killing) on a host seeking female during the entire BMS stage, essentially simulating untreated bed nets;
-
BMD Resting : imposes an additional killing effect for a female mosquito in the BMD stage, and the killing effect sustains every hour (of the one to 2.5 days duration in BMD; see Equation 7) until the mosquito enters the gravid stage or dies. Thus, BMD Resting simulates a continuous killing effect on a female mosquito during the entire BMD stage, essentially simulating IRS;
-
G Foraging : works similarly as BMS Foraging , imposing an additional killing effect for a female mosquito in the G stage seeking an aquatic habitat for oviposition. The killing effect is in action whenever a female is seeking a habitat (with P FindHabitat =25%, meaning 25% probability of finding a habitat in each hour during G), and continues every hour until it successfully finds a habitat or dies. Since the core model implements skip-oviposition (using several different habitats to oviposit a few eggs in each), the duration of the killing effect increases with each successive oviposition attempt. Thus, G Foraging simulates a continuous killing effect on a habitat-seeking female during the entire G stage, essentially simulating lethal ovitraps.
HVCI | Interpretation | Real-world mapping |
---|---|---|
L
Entering
| Imposes a one-time killing effect (a one-time hazard) when an egg enters the larva stage | LSM by insecticidal control |
L
Updating
| Imposes an additional killing effect for a larva; the killing effect sustains every hour during the entire larval development stage (see Equations 2–5) until the larva enters the pupa stage or dies | LSM by biological control |
BMS
Foraging
| Imposes an additional killing effect for a host seeking female mosquito in the BMS stage; the killing effect is in action whenever a female encounters a host (with P
FindHost
=25%) in BMS, and occurs over every hour until the mosquito successfully gets a blood meal (and then enters the BMD stage) or dies; may occur in multiple gonotrophic cycles | ITNs |
BMS
Foraging, K=0%
| A special case of BMS
Foraging
with no killing effectiveness; simulates a continuous effect (with no additional killing) on a host seeking female during the entire BMS stage; may occur in multiple gonotrophic cycles | Untreated bed nets |
BMD
Resting
| Imposes an additional killing effect for a female mosquito in the BMD stage, and the killing effect sustains every hour of the 1–2.5 days duration in BMD (see Equation 7) until the mosquito enters the G stage or dies; may occur in multiple gonotrophic cycles | IRS |
G
Foraging
| Imposes an additional killing effect for a female mosquito in the G stage seeking an aquatic habitat for oviposition; the killing effect is in action whenever a female is seeking a habitat (with P
FindHabitat
=25%) in G, and occurs over every hour until it successfully finds a habitat or dies; may occur in multiple gonotrophic cycles | Lethal ovitraps |
(IA, BMS, BMD, G)
Entering
| Imposes an additional killing effect (a one-time hazard) for female mosquitoes entering the IA, BMS, BMD, and G stages; may occur in multiple gonotrophic cycles during BMS, BMD, G | ATSB |
(IA, BMS, BMD, G)
Resting
| Imposes an additional killing effect for female mosquitoes resting in the IA, BMS, BMD, and G stages; the killing effect occurs over every hour (when mosquitoes are resting) in all of these stages, and in multiple gonotrophic cycles during BMS, BMD, G | Sugar meal traps |