CTD/MAL/AFRO/97.4

Insecticide treatment of nets
Nets to be treated are those already owned/used traditionally by communities, or introduced as a public health intervention. In the former instance, the nets could be of different sizes, shapes, and fabric. An assessment of these can help to prepare the dipping mixtures more accurately so that the insecticide treatments achieve targeted dosages. Where nets are introduced, the specified standards and quality requirements can be met more easily with appropriate planning.

To correctly treat a net with an insecticide, a net of a given size/surface area is treated with an appropriate insecticide mixture (which has been prepared by mixing a specified amount of insecticide formulation, with a specified quantity of water) in order to obtain the target dosage of the insecticide.

Logistic requirements
The supply/material requirements for insecticide treatment of nets are:

• water,
• insecticide formulation,
• measuring devices for water and insecticide,
• container to dip the net(s), and to collect insecticide drips after dipping,
• rubber gloves and protective clothing including a face-mask especially when many nets are treated, when treatments are done daily or for prolonged periods, and
• spray equipment when nets are sprayed.

Preparation of insecticide mixtures
The preparation of an insecticide mixure for net treatment requires information on:

• the number of nets to be treated, and their sizes or the surface area involved;
• the amount of water to prepare the mixture (depending on how much water they absorb; and
• amount of insecticide to treat the nets.

Calculating surface area of net to be treated

The surface area is usually presented in square meters (m²). Examples of calculating this for the more commonly used rectangular, and conical designs are as follows:

Rectangular net

Hang the net up, measure the width, length, and height (in metres), and

1. Calculate the area of the top: i.e. width x length
2. Calculate the area of the sides, and ends. i. e. heigth x total distance around base of the net;
3. c) Add a) and b) calculations to get the total area of the net.

Thus total surface area (S) = sum of the surfaces of, the 2 sides, the 2 ends, and the area of top = 2 (L x h) + 2 (w x h) + 1 (L x w),
where L = length, w = width, and h = height, or perimeter x height + area of top.

For example assume, length=1.8 m; width=1.3 m; height=1.5 m. Then the,

1. Area of the top = 1.3 x 1.8= 2.3 sq m
2. Area of sides and ends = 1.5 x 2( 1.3 + 1.8) = 1.5 x 6.2 = 9.2 sq m
3. Total area of net = 2.3 + 9.2 = 11. 5 sq m

Conical net

Total surface area (S) = circumference x distance up the slope x 0.5

Calculating the amount of water to prepare the mixture

This is the same as the amount of water to saturate the net, i.e. the water retention capacity of the wet fabric. This depends on the type of fabric. To determine this:

• Select about 3 nets of each type of net (i.e. with same material, size);
• Dip each net thoroughly for few minutes in a known quantity of water (Vi) in a bucket or basin;
• Remove the net from the container, wring and hold for 5-30 seconds over the bucket or basin to catch any drips;
• Repeat with each net;
• Measure the remaining water in dipping bucket (Vr);
• Average amount of water absorbed by a net
  (Vn) = Vi-vr
  number of nets dipped

The amount of water needed for each type of net can be determined by checking a sample, and calculating for the total number of nets to be treated.

Calculating of amount of insecticide to treat nets

The amount of insecticide to treat a net depends on the total surface area of the net, the type of fibre, and the insecticide, i.e. the type, strength, formulation, and the target dosage (TD) presented in mg or g/m².

In calculating the insecticide requirements, the active ingredient (a.i), and the commercial formulation (c.p.) are taken into account.

(a)     Amount of active ingredient (a.i):

The active ingredient (a.i) in mg or g (or ml for the WP formulations) = surface area of net (m²) x target dose (mg or g a.i/m²). For example,

(b)     Amount of commercial product (c.p.):

Commercial formulations are generally presented as:

1. percentage (%),
2. g/litre for the liquids, and
3. g/kg for powders.

The labels must be read carefully for the concentration, a) keeping in mind that some manufacturers label their products in % i.e. g/100 ml, and some in g/litre, and b) that fifty per cent (50%) is the same as 500 g/litre. Thus care is needed in relating the active ingredient (a.i) to the commercial product. For example, Permethrin, expressed as EC 50 (50%) contains 500 g a.i/litre; Deltamethrin, SC 2.5 expressed as 2.5%, contains 25 g/litre.

The amount of insecticide formulation required can be calculated as shown in the following examples:

Thus a 500 ml dipping mixture that would be needed for one net (based on water retention capacity) will comprise of 10 ml of insecticide formulation, and 490 ml of water.

The commercial product and the water (measured previously) must be mixed thoroughly and carefully in wide, shallow containers (buckets or basins), the latter to limit side effects from insecticide inhalation on the workers. The insecticide container must be rinsed well with the water to be used for the solution to prevent waste.

To simplify the calculations in preparing dipping mixtures for collective dipping, it may be necessary to treat together: a)  nets/sets of nets belonging to a family assuming these to be of comparable/similar material; and b)  nets made of more or less the same fabrics and bearing in mind that cotton absorbs more (about twice) liquid than the synthetics, and that the efficacy of insecticides varies with the materials.

Charts and tables may be prepared (and made readily available) indicating the quantities of mixtures to be prepared with each insecticide according to the target dosages and water retention capacities, and on the amounts of insecticides (commercial products) for nets of different sizes.

Insecticide treatment methods
Nets can be insecticide-treated by dipping, or spraying with standard hand compression sprayers. Irrespective of method, all nets must be washed properly before being treated.

Dipping

Nets can be dipped individually or collectively in batches of ideally similar types in terms of materials. Each net is unfolded, fully submerged in the insecticide solution, and kneaded (fig. 6) until saturated with liquid. Dipped nets are wrung above the dipping container to collect the drips (fig. 7).

Fig. 6 Dipping/kneading	Fig. 7 Dipped net wrung

(a)     Individual treatment (dipping) of nets:

Dipping nets one by one may lead to non uniform impregnation, unless care is taken to knead the net until it is evenly wetted. This is time consuming and less practical when large numbers of nets are to be treated in a short time.

Individual dipping is possible in plastic bags. The net is placed first in the bag, the exact amount of mixture needed to saturate the fabric is poured, and kneaded thoroughly. The net is removed and dried; wringing is not necessary.

(b)     Collective dipping:

Here several nets, e.g. batches of five or tens are dipped together. In planning, an estimate must be made (e.g. through sample KAP surveys) of the numbers of nets of each type (fabric/material, size, and shape). This helps more accurate calculation of the water and insecticide requirements, and the preparation of dipping solutions to meet the target dosages. If such an assessment is not possible a compromise may be a dilution of one litre of insecticide e.g. deltamethrin SC 25, or lambdacyhalothrin CS 25 or 1 litre of permethrin EC 50, with 49 litres of water. Nets of different fabrics must be sorted out and dipped accordingly. This may necessitate dipping together the nets of individual families assuming these to be of comparable material. Dipped nets removed one by one after a few minutes are wrung thoroughly above the dipping container, and placed in an open plastic basket for some time over the decantation part to allow draining. Some families may not wish their nets to be mixed and immersed in the same dipping bath with those of others. Nets of each family may be kept separately to avoid accidental interchange.

As pointed out earlier, more absorbent material such as cotton absorbs more insecticide per square metre than with synthetic nets. However for the same insecticide effect of e.g. permethrin or lambdacyhaéothrin , a higher dose per square metre is required on cotton than on synthetic material. These differences on cotton and synthetic tends to balance out and where a mixture of light cotton and synthetics nets have to be dipped, a single mixture could be used.

A team of 2-3 trained persons assisted by a few local people can dip at least 200 nets a day.

Spraying of nets

Spraying allows collective treatment of a large number of nets in a short time. This is quick and a net could be treated in a few seconds, often less than half a minute. Spraying nets is to some extent comparable to spraying of walls where an insecticide solution is sprayed aiming at a target dosage on the net surface. Spraying nets requires more expertise and may be undertaken by those experienced in the use of spray machines and in spraying operations such as those undertaken in malaria control programmes and in agriculture.

Nets must be cleaned and ready for spraying, hung in situ over the bed (in Sichuan, China more than one million nets are sprayed annually in situ, without taking them outside)., or outdoors, away from windy places, children, food and water bodies such as rivers and streams. Sprayed nets must be kept outdoors to dry and must not be used before they are completely dry.

Achievement of good quality spraying requires, properly functioning spray machines with correct nozzles, etc. to deliver proper swath width, and flow rates, and correct spray procedures /techniques that ensure the required pressure, the distance/angle between nozzle and the surfaces sprayed, and the speed. The equipment must be checked regularly. Procurement of the same type of equipment/spare parts facilitates replacement, maintenance of equipment, and training compared to the use of different types of machines. Spray personnel must be appropriately trained including refresher training, and supervised to ensure quality of equipment and performance. Spraying nets may be relevant and/or can be easier in:

• Areas where house spraying is ongoing or has been discontinued, and where experienced staff could be trained in net treatments in a short time and with minimum inputs;
• Other areas where people are familiar with the use of insecticides and spray equipment such as in agricultural areas;
• In refugee camps, resettlement areas where treatment of tents, temporary shelters and nets are urgently needed to deal with disease outbreaks; and
• Where a large number of nets have to be treated in a very short period of time.

Pre-treated nets

Effective, permanent insecticide treatments which allow easy, safe and cheap distribution would be ideal for ITMN programmes. However net pretreatment methods have not yet been proven to allow residual effects of insecticide treatment to cover the life of the nets. Olyset nets have not been long enough to know how long their efficacy lasts.

As re-treatment is needed eventually, pre-treatment (at factory, warehouse, shops, or otherwise) prior to transport, distribution and sales would only delay opportunities to address the re-treatment issues from the start of the programme. It is pointed out that this could be useful to start programmes until other arrangements are being made.

Drying treated nets

Treated nets may be dried, placed flat on clean non-absorbent surfaces such as plastic sheeting, (fig. 8), or spread on beds or mattresses (with bedsheets removed, and this may help kill bed bugs etc)., or hung up in the shade in the open (fig. 9).

Fig. 8 Drying treated nets flat	Fig. 9 Drying treated nets hung

In all instances, the nets should be arranged with minimum folds as possible, and turned occasionally to ensure that the insecticide is deposited evenly. Hanging nets immediately after dipping must be avoided to prevent dripping, loss of solution, and uneven spread of insecticide. The insecticide adheres better to nets dried in horizontal position; in vertical position they may dry faster as would also be when exposed to sun and wind. Long exposure to bright sunlight should be avoided as the pyrethroids can be destroyed.

Time taken to dry also depends on the fabric, the amount of insecticide absorbed, and the surface area. Cotton takes longer. Drying should be done close to the dipping sites. Nets treated should be kept clean during dipping or drying.

Organization of net treatment sessions
People must be informed in advance of the treatment schedules in their respective areas and asked to wash the nets on the day before the treatment. If several teams work in a village or an area, they must communicate their schedules with the exact locations. The locations for refilling spray tanks must be identified especially for the mobile teams.

The number of nets to be treated should be determined as far as possible, and the water and insecticide requirements estimated correctly. Buffer stocks of insecticides and solutions must be ensured to avoid interruption due to their shortage. Having to wait a long time to get the nets retreated can discourage people and eventually compromise the programme.

As already pointed out, the dipping must be done outdoors in large shallow containers to protect the dippers from inhaling insecticide fumes. This is particularly important when large numbers of nets are to be treated continuously over a period of time, or daily. Care is needed to prevent insecticide splashing on skin, and nasal irritation of the dippers. The dippers must be interchanged periodically to avoid over exposure of any one individual to insecticide fumes. During net dipping, use of strong rubber gloves are recommended to avoid risk of skin irritation. Goggles or other eye protection are also recommended for those who work close to the dipping container, to avoid risks of splashes in the eye.

Spraying nets against the wind must be avoided to prevent any insecticide falling on people spraying. People, especially children, and also food must be kept at a distance to avoid contamination.

Spillage and waste of insecticides or water must be avoided when preparing the mixtures. After the treatment, the equipment used must be cleaned, but never in rivers, streams, or ponds as pyrethroids are toxic to fish. Surplus insecticide, waste packaging and contaminated material should be disposed of e.g. in pit latrines, or buried far away from human settlements, water sources (wells, rivers, streams and fish ponds). Empty insecticide boxes, contaminated containers must be destroyed to prevent their use for other purposes. Adequate care must be taken to avoid environment contamination throughout the work.

Net owners, other members of the community should be invited to observe, and where appropriate to participate in nettreatment so that they may recognize and appreciate the importance and implications of the activity. The community health workers (CHW) and other health providers in the village/community must be active partners, properly motivated to participate in the (re)treatment, and in the support of the overall programme.

People must be advised to keep and use treated nets away from fire places and lamps to prevent fire hazards, informed that such risks are higher where people cook and sleep in the same room. They must also be advised to prevent children putting treated nets in their mouth.

The community must be informed of the potential risks and effects of insecticide contamination, and be taught measures to be taken if contamination occurs. The need to seek prompt medical assistance and to refer to a physician if any signs of such effects are detected or suspected must be emphasized.

Effect of washing treated-nets, care and use
The effectiveness of treated nets can be reduced with treatment with an inadequate dose, and from loss or reduced dosages insecticide from washing treated nets. The treatment efficacy is considered to be more dependent on the amount of washing than on the time after the treatment.

Thus people should be, a) advised to get nets (re)treated on time, b) to wash the nets before the insecticide treatment, but discouraged from doing so after the treatment, c) informed of the consequences of frequent washing of treated nets, and d) advised to retreat the nets which have been washed more than twice to sustain efficacy, through appropriate information, education and communication (IEC) messages, and opportunities to get the required net (re)treatments must be provided.

When in use, nets should be hung down to cover the entire bed, and tucked under the mattresses or sleeping mats etc.. During daytime, they should be tied up, out of the way to avoid being damaged.

The insecticidal effect on a treated net at a given time may be checked, to provide guidance for re-treatment of nets in operational use, through "bio assay tests". Here a sample of anophelines (susceptible to the insecticide under consideration) is allowed to contact insecticide on treated net for a standard time (e.g. 3 minutes) by confining the mosquitoes in the WHO bioassay cones attached to the net. Subsequent observations are made on, the percentage knocked down after one hour, and the mortality after 24 hours. Generally nets freshly treated with the recommended dose of an insecticide is expected to give almost a 100% mortality. After a period of use, and in particular after washing, the mortality tends to decline. From an operational context, the efficacy of the pyrethroids in treated nets is expected to last 612 months depending on the insecticide, but less with nets washed frequently. In general, nets may be treated at 6 monthly intervals, depending on the transmission pattern; with timing of treatments planned immediately prior to the transmission season.

Safety, side effects from pyrethroid exposure
Reports on side effects from pyrethroid use are related to the workers who spend long hours mainly in net-dipping (often compelled to inhale solvent vapour), and the ITMN users. The former in particular are reported to suffer from non specific symptoms of mild intoxication such as headaches which have been transient. Exposure to skin especially the mucous membrane have caused paraesthesia (tingling, burning sensations) caused by temporary transient effects on sensory nerves. Such symptoms are common with the alpha cyano compounds (deltamethrin and lambdacyhalothrin etc.) and are rare with permethrin. Deltamethrin is reported with more severe side effects on polyethylene nets.

Other reports include painful irritation caused when emulsions splash in the eyes, tingling sensation when droplets fall on the skin, facial swellings of those handling freshly dipped, dried ITMNs, and nasal irritation and sneezing (lasting a few days to 2 weeks) of those sleeping under freshly treated nets. Closer monitoring with documentation and dissemination of information on related observations and experience are needed, especially for the alphacyano compounds.

The side effects could have operational consequences in discouraging people from the use of ITMNs, and/or prompt them to wash the nets soon after treatment. Appropriate IEC messages should be developed and delivered to convey to the public, the potential side effects and the conditions under which they may occur, the precautionary possibilities and actions to be taken if side effects are encountered or suspected.

Vector response to insecticides
Vector response to insecticides in terms of behaviour and insecticide susceptibility is an important determinant of the efficacy of ITMNs. If and how ITMNs impact on the vector and/or malaria must be known or ascertained when planning, and monitoring the implementation.

A)     Vector behaviour

Insecticide use can lead to changes in the vector behaviour such as resting, biting sites and times, sometimes causing shifts in peak biting periods.

The vectors' behavioural responses to pyrethroids can have significant epidemiological implications. The behavioural response depends on the type of insecticide, dosage/formulation, and the inert material/solvent used in the formulations. The pyrethroids can cause deterrent, irritant, killing, and knock down effects, or feeding inhibition on the vectors. Deterrence may prevent entry and favour mosquito exit from houses; thus providing personal protection to people indoors. Where such mosquitos are not killed outdoors, adequate impact on transmission and community level protection may not occur unless a good level of ITMN coverage is achieved to effect mass killing of the vector populations.

Different mosquito species e.g. Culex quinquefasciatus and Anopheles gambiae have responded differently with permethrin-treated nets. Such information is important in planning ITMN programmes in urban areas, and other situations where protection from nuisance insects has been a strong motivation for ITMN use.

The choice between insecticides with high deterrency or high killing effect may depend on the targeted objective of the intervention, whether personal protection, or mass protection of a community. The insecticide/vector interaction however is not very clear at present, and the relevant information is inadequate. More information is needed: a)  on the effects, advantages and disadvantages in relation to the deterrent/repellent, irritant, knock down and killing effect of different insecticides, and dosages including sub-lethal dosages, and at different periods after the insecticide treatments, and b) on their impact in relation to personal and community level protection, and transmission.. The relevant information is necessary for the selection of insecticides, and in preparing IEC messages to convey to the people the expectations from insecticides used in nettreatment. Some of the information can be collected with monitoring during operational implementations; others through relevant operational research.

B)     Vector resistance to insecticides

Vector susceptibility is basic for the efficacy of insecticides. The eventual development of insect/vector resistance to insecticides is inevitable if the insect populations concerned are continually exposed to insecticides, irrespective of the purpose for which they are used. The types of resistance/resistance spectra depend on the mechanism(s) prevalent in the insect population and are being selected. A number of resistance mechanisms are known in insects/mosquitos; some conferring broad multiple resistance and which also involve the different pyrethroids. At present the insecticides for net-treatment are limited to the pyrethroids and a pseudopyrethroid, etofenprox. Anopheles strains which are resistant to one of these compounds are often cross resistant to others also. Despite limited monitoring and reporting, such resistances are already encountered in a number of malaria vectors including some populations of An. gambiae in Africa. The operational implications of these resistances are not yet known, or investigated; but the findings may alert potential threats to the continued use of the pyrethroid group of insecticides and the sustainability of the ITMN strategy.

The use of the pyrethroid insecticides is also spreading fast, in public health (house spraying, ITMNs, space spraying) in addition to their already extensive use in agriculture and in household pesticides. Insecticide resistance related information is thus necessary to guide planning, implementation and evaluation of insecticide uses. It is therefore necessary that the insecticide susceptibility or resistance status of the vectors be assessed, with the practical implications of resistances already encountered (especially at high levels) in different representative situations investigated.

(i)     Assessment of insecticide susceptibility status

At present, monitoring coverage, and information base on susceptibility or resistance status is limited and patchy. Monitoring must be undertaken/improved for the insecticides in use, and for the potential alternatives. These must be focused in representative areas where:

• Insecticide use has been ongoing for a known period of time, or is planned for bednet treatment and for other malaria/vector control interventions and public health purposes;
• resistance and multiple resistance (especially involving the pyrethroids) are reported or suspected; and
• considerable amounts of insecticides have been in use for a known period of time:
  • for agriculture,
  • in indoor residual spraying,
  • for treatment of bednets and other material, and
  • as domestic insecticides.

In each of the above areas, the monitoring should cover diverse epidemiological situations, and vectors with different breeding, resting and feeding habits which are likely to influence their exposures to insecticide selection pressures. The monitoring may be supported by networking activities (page 54).

As pyrethroid resistance levels vary with mosquito age; tests are needed on adults collected directly from the field, as well as on adults emerged from the field collected larvae.

The WHO test procedure for the use of "discriminating dosages" must be used in the monitoring, as is also the standard formats (WHO/CTD/VBC/Resis.1a.97 (adult), WHO/CTD/VBC/Resis.1b.97 (larva), WHO/CTD/VBC/Resis.1c.97 (pesticide use) developed to record and report relevant data. These will enable collation and comparison of data from different sources based on standardized test procedures and collection of information, to facilitate exchange, use and extrapolate experience.

(ii)     Practical implication of resistance, and other investigations

It is emphasized that the WHO test alone is not the criterion to establish whether an insecticide in use is effective or not under field operational use. The results do not simulate or represent the actual insect response under the field operational use of the insecticide concerned. Resistance detected during these tests however is a strong indication that mosquito populations are responding to selection, thus signaling the need for further monitoring and field observations in order to guide the planning of insecticide uses. The information also provides opportunities to examine the resistance spectra.. When investigating reports of resistance, the operational elements of the programme, and the entomological and disease impact indicators must be examined critically in order to determine the conditions and levels at which resistance can lead to control failures.

Information on resistance must be collected and correctly documented, and disseminated and exchanged, as for all other important aspects of the programme.

Some nuisance insects may be more tolerant and/or have already developed resistance to pyrethroids. Others may rapidly develop resistance. Whether such occurrence could compromise compliance of the people whose motivation to use ITMNs is primarily linked to the protection from nuisance insects, needs to be examined. Appropriate action, and IEC messages must address this issue.

Information management
ITMN implementation related information must be readily available, ideally as part of the information management systems already available, or being developed for malaria control. Linkages must be established with other relevant information systems, within and outside the health system including NGOs who may contribute to the implementation.

Purpose

The use of information must be directed to:

• Convince the macro-economic level policy and decision makers including financial bodies and other support agencies, and the implementers concerning specific requirements, including support;
• Select and prioritize targets for ITMNs;
• Select materials (nets, insecticides, spray equipment);
• Guide net (re)treatment;
• Identify the types and contents of IEC messages, and assess communication skills and success of community mobilization and intersectoral actions;
• Identify gaps, shortcomings;
• Identify training and research needs, and evaluate their performance and achievements;
• Examine the relevance and/or effectiveness of the ITMN strategy, the processes and activities, of the insecticides used, and the use of ITMNs by the community;
• Provide information for programme adjustments.

Type of information

The information needs could be general, or target-oriented. The types of information that may be required are listed in Annex 4. It is to be noted that most of this information need not be collected exclusively for the ITMN programmes. Many could be accessed from what is already available and through other sources as listed in Annex 5.

How to collect

There is no single method to collect information. Examples for planning are:

• List the minimum data/information that is required, for what and at each level of implementation;
• Clarify from where, by whom, how and when to collect;
• Establish processes to collect, and identify the channels to obtain the information with minimum efforts and inputs;
• Develop suitable data collection formats;
• Train the data collectors and users of information;
• Make the best use of the existing information systems, adapting them to ITMN programme needs.

Documentation, exchange and sharing of information

As indicated earlier, experience gained in ITMN implementation is limited, and the programmes are to be progressively expanded, benefiting from experience. Existing information and that collected during the implementation must be made widely available. Mechanisms must be established providing for opportunities to promote reporting, publishing and dissemination of information and experience. These should be in relation to the operational aspects and related research undertaken in different epidemiological situations and institutional arrangements. Information updating, rapid transfer, exchange and sharing within and outside the country must be promoted.

An updated inventory may be maintained of all ongoing ITMN related activities (operational and research) in the country indicating, for example, their location, coverage, time frames, and expenditures. The experience gained and achievements made in each of these activities must be periodically updated in qualitative and quantitative terms. Suitable formats must be developed and used to guide and standardize the information gathered and reported on activities from different sources. Information exchange within and among the countries may necessitate periodical meetings of relevant personnel in workshops and seminars, regular communication through newsletters, and through national, regional networking programmes (which may be established) involving relevant scientists and institutes.

Operational aspects
The end-point determinant of the effectiveness of an ITMN programme is the use of ITMNs by those at risk of contracting malaria. Others' inputs must lead to this end in order to ensure:

ITMN programmes require that the potential ITMN-users have access to nets, and have opportunities to get them treated on time with correct amounts of insecticides. Appropriate insecticides must be selected and good quality procurements made at low cost. They must be stocked and delivered to treatment levels. The efficacy and retention of insecticides on treated nets must be assured. Nets must be used properly (to prevent mosquitos from entering the nets in use) and at least during periods of peak vector biting and disease transmission. People must know the conditions for using them to get optimal benefits. The costs must be met and operations sustained, thus requiring appropriate support. These actions, especially on a large-scale, have a number of technical, sociocultural, operational and managerial implications. Policy, institutional and collaborative arrangements may be involved.

Annex 1 lists the activities necessary to sustain large-scale implementation. For each activity area, indications are given as to who may be responsible and at what level. The probable processes or mechanisms, and the needs and conditions of support to be met are indicated but are neither prescriptive nor comprehensive. They may be considered in overall programme planning, and in planning participation and support to specific activity areas. The format may be adapted to local circumstances, and can include resources, training, and research issues.

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