SimpleBednet

The SimpleBednet intervention class implements insecticide-treated nets (ITN) in the simulation. ITNs are a key component of modern malaria control efforts, and have recently been scaled up towards universal coverage in sub-Saharan Africa. Modern bednets are made of a polyethylene or polyester mesh, which is impregnated with a slowly releasing pyrethroid insecticide. When mosquitoes that are seeking a blood meal encounter a net, the feeding attempt is blocked as long as the net retains its physical integrity and has been correctly installed. Blocked feeding attempts also carry the possibility of killing the mosquito. Net ownership is configured through the demographic coverage, and the blocking and killing rates of mosquitoes are time-dependent.

SimpleBednet can model the bednet usage of net owners by reducing the daily efficacy. To model individuals using nets intermittently, see UsageDependentBednet. To include multiple insecticides, see MultiInsecticideUsageDependentBednet.

At a glance:

  • Distributed to: Individuals

  • Serialized: Yes, if it has been distributed to a person.

  • Uses insecticides: Yes. Insecticides can be used to target specific species or other subgroups.

  • Time-based expiration: No, but it will expire if the WaningEffect expires (WaningEffectRandomBox and WaningEffectMapLinear expire).

  • Purge existing: Yes. If a new intervention is added to to the individual, the existing intervention of the same name is removed when the new one is added. It is possible to have multiple SimpleBednet interventions attached to an individual if they have different Intervention_Name values.

  • Vector killing contributes to: Indoor Before/After Feeding

  • Vector effects: Repelling, blocking, killing

  • Vector sexes affected: Females only

  • Vector life stage affected: Adult

Note

Parameters are case-sensitive. For Boolean parameters, set to 1 for true or 0 for false. Minimum, maximum, or default values of “NA” indicate that those values are not applicable for that parameter.

EMOD does not use true defaults; that is, if the dependency relationships indicate that a parameter is required, you must supply a value for it. However, many of the tools used to work with EMOD will use the default values provided below.

JSON format does not permit comments, but you can add “dummy” parameters to add contextual information to your files. Any keys that are not EMOD parameter names will be ignored by the model.

The table below describes all possible parameters with which this class can be configured. The JSON example that follows shows one potential configuration.

Parameter

Data type

Minimum

Maximum

Default

Description

Example

Blocking_Config

json object

NA

NA

NA

Defines a waning effect that determines the probability that a host-seeking vector is blocked from reaching a human host. Blocked vectors are then elligble to be killed according to the Killing_Config parameter. Specify how this effect decays over time using one of the Waning effect classes.

 
{
  "Blocking_Config": {
    "Box_Duration": 3650,
    "Initial_Effect": 0,
    "class": "WaningEffectBox"
  }
}

Cost_To_Consumer

float

0

999999

3.75

The unit cost per bednet (unamortized)

 
{
  "Cost_To_Consumer": 4.5
}

Disqualifying_Properties

array of strings

NA

NA

[]

A list of IndividualProperty key:value pairs that cause an intervention to be aborted (persistent interventions will stop being distributed to individuals with these values). See NodeProperties and IndividualProperties parameters for more information. Generally used to control the flow of health care access. For example, to prevent the same individual from accessing health care via two different routes at the same time.

 
{
  "Disqualifying_Properties": [
    "InterventionStatus:LostForever"
  ]
}

Dont_Allow_Duplicates

boolean

0

1

0

If an individual’s container has an intervention, set to true (1) to prevent them from receiving another copy of the intervention. Supported by all intervention classes.

 
{
  "Dont_Allow_Duplicates": 0
}

Insecticide_Name

string

NA

NA

UNINITIALIZED STRING

The name of the insecticide defined in the configuration parameter Insecticides for this intervention. If insecticides are being used, this must be defined as one of those values; if they are not being used this can be empty. It cannot have a value if you did not configure the configuration parameter Insecticides.

 
{
  "Insecticide_Name": "carbamate"
}

Intervention_Name

string

NA

NA

SimpleBednet

The optional name used to refer to this intervention as a means to differentiate it from others that use the same class.

 
{
  "Intervention_Config": {
    "class": "SimpleBednet",
    "Intervention_Name": "Northern region bednet distribution"
  }
}

Killing_Config

json object

NA

NA

NA

Defines a waning effect that determines the probability that a blocked vector is killed due to the intervention. Killing is conditional on being blocked: only blocked vectors are able to be killed. Specify how this effect decays over time using one of the Waning effect classes.

 
{
  "Killing_Config": {
    "Box_Duration": 3650,
    "Initial_Effect": 0.53429,
    "class": "WaningEffectBox"
  }
}

New_Property_Value

string

NA

NA

“”

An optional IndividualProperty key:value pair that will be assigned when the intervention is applied. See NodeProperties and IndividualProperties parameters for more information. Generally used to indicate the broad category of health care cascade to which an intervention belongs to prevent individuals from accessing care through multiple pathways. For example, if an individual must already be taking a particular medication to be prescribed a new one.

 
{
  "New_Property_Value": "InterventionStatus:None"
}

Repelling_Config

json object

NA

NA

NA

Defines a waning effect that determines the probability that a vector is repelled due to the intervention. Specify how this effect decays over time using one of the Waning effect classes.

 
{
  "Repelling_Config": {
    "Box_Duration": 3650,
    "Initial_Effect": 0,
    "class": "WaningEffectBox"
  }
}

Usage_Config

json object

NA

NA

NA

The user-defined WaningEffects to determine when and if an individual is using a bed net. Specify how this effect decays over time using one of the Waning effect classes.

 
{
  "Usage_Config": {
    "class": "WaningEffectConstant",
    "Initial_Effect": 1.0
  }
}

{
    "Events": [{
        "class": "CampaignEvent",
        "Nodeset_Config": {
            "class": "NodeSetAll"
        },
        "Start_Day": 1460,
        "Event_Coordinator_Config": {
            "class": "StandardInterventionDistributionEventCoordinator",
            "Target_Demographic": "Everyone",
            "Demographic_Coverage": 0.7,
            "Intervention_Config": {
                "class": "SimpleBednet",
                "Cost_To_Consumer": 3.75,
                "Repelling_Config": {
                    "Initial_Effect": 0.1,
                    "Decay_Time_Constant": 730,
                    "class": "WaningEffectExponential"
                },
                "Killing_Config": {
                    "Initial_Effect": 0.6,
                    "Decay_Time_Constant": 1460,
                    "class": "WaningEffectExponential"
                },
                "Blocking_Config": {
                    "Initial_Effect": 0.9,
                    "Decay_Time_Constant": 730,
                    "class": "WaningEffectExponential"
                },
                "Usage_Config": {
                    "class": "WaningEffectConstant",
                    "Initial_Effect": 1.0
                }
            }
        }
    }],
    "Use_Defaults": 1
}