By December 2018, questionnaire responses had been received from 94 countries, indicating a response rate of 48%. The response rate was 54%, 55%, 76% and 19%, respectively, from the African, Asia-Pacific, Latin American & Caribbean, and European & Others Groups of countries.
Capacity for insecticide susceptibility testing (i.e. WHO or United States Centres for Disease Control and Prevention (CDC) phenotypic bioassays) was reportedly in place in most countries across regions, except in the European & Others Group (Table 1). Representative sentinel sites, needed for monitoring of temporal changes in the prevalence of resistance, had been established in approximately half of the countries in the Africa, Asia-Pacific and Latin American & Caribbean Groups (Table 1). Insectaries to support insecticide susceptibility testing and efficacy testing were reported to be in place in part of the countries across regions. Capacity for molecular testing and biochemical testing was reported from few countries but was most common in the African Group of countries (Table 1).
Table 1
Capacity for insecticide resistance monitoring
| African | Asia-Pacific | Latin American & Caribbean | European & Others |
Topic | % | (n) | % | (n) | % | (n) | % | (n) |
Insecticide susceptibility testing | 68 | (28) | 70 | (30) | 80 | (25) | 30 | (10) |
Representative sentinel sites established | 50 | (28) | 57 | (30) | 36 | (25) | 10 | (10) |
Insectaries in place for bioassays | 57 | (28) | 50 | (30) | 68 | (25) | 40 | (10) |
Molecular testing of resistance | 39 | (28) | 17 | (30) | 28 | (25) | 20 | (10) |
Biochemical testing of resistance | 36 | (28) | 20 | (30) | 24 | (25) | 20 | (10) |
Data presented as % of responding countries per Regional Group that gave a positive response regarding each topic (n indicates number of responding countries for each topic) |
Pesticide procurement is a demanding process to ensure the availability of correct amounts of quality products that are efficacious against targeted vectors. Most countries, apart from those in the European & Others group, reported that the insecticide susceptibility status of vectors was used as a criterion for selection of pesticides to be procured (Table 2).
A small fraction of countries reported that problems were encountered with estimating the appropriate amounts of vector control insecticides to be procured for normal or routine situations (Table 2). However, a substantially larger fraction of countries experienced problems estimating the amounts needed for emergency situations (e.g. disease outbreaks), particularly in the African and Asia-Pacific Groups.
In most Asia-Pacific countries, a requirement for procurement of vector control insecticides was that quality control was conducted before and/or after shipment into the country (Table 2). This requirement was less common in the other regions. Pesticide procurement may benefit from regional collaboration. In this regard, half the countries in the Latin American & Caribbean Group reported that procedures, requirements and guidelines for procurement were aligned with those of other countries in the (sub-) region, whilst such alignment was less common in other regions (Table 2).
Table 2
Conditions and challenges of procurement of vector control insecticides
| African | Asia-Pacific | Latin American & Caribbean | European & Others |
Topic | % | (n) | % | (n) | % | (n) | % | (n) |
Insecticide susceptibility status as criterion for selection | 89 | (28) | 80 | (30) | 92 | (25) | 38 | (8) |
Problems estimating amounts needed for routine/normal situations | 15 | (27) | 27 | (30) | 8 | (24) | 13 | (8) |
Problems estimating amounts needed for emergency situations | 32 | (28) | 40 | (30) | 17 | (24) | 11 | (9) |
Quality control (pre- and/or post-shipment) required for procurement | 56 | (27) | 73 | (30) | 36 | (25) | 0 | (9) |
Procurement requirements aligned with other countries | 22 | (27) | 32 | (28) | 52 | (25) | 20 | (10) |
Data presented as % of responding countries per Regional Group that gave a positive response regarding each topic (n indicates number of responding countries for each topic) |
Most countries, except in the European & Others group, reported that the Ministry of Health procured pesticides for malaria control at central level (Table 3). For arboviral diseases and other vector-borne diseases, fewer countries in the African and Asia-Pacific groups reported central-level pesticide procurement (Table 3). In addition, in most countries there were other agencies or authorities (notably, local authorities, external programmes, private sector agencies) apart from the central-level procuring agency, that procured pesticides for vector control (Table 3). In 22% of responses, procurement was centralized only; in 20% of responses, procurement was decentralized only; and in 58% of responses, procurement was both centralized and decentralized.
WHO routinely evaluates vector control products, and publishes recommendations on approved products [15]. In most countries in the African and Asia-Pacific Groups, procurement by the central-level Ministry of Health was restricted to those products that have been recommended by WHO (Table 3). However, products that were procured by other agencies at decentralized level were less commonly restricted to WHO recommendations in most regions (Table 3).
WHO quality standards (i.e. pesticide specifications) were included in the procurement requirements by the central-level Ministry of Health in most countries, except in the European & Others group (Table 3). However, for procurement at decentralized level by other agencies, quality standards were less commonly a requirement (Table 3).
Table 3
Procedures for procurement of vector control insecticides
| African | Asia-Pacific | Latin American & Caribbean | European & Others |
Topic | % | (n) | % | (n) | % | (n) | % | (n) |
Procurement for malaria control at central level | 63 | (27) | 73 | (30) | 84 | (25) | 20 | (10) |
Procurement for arboviruses at central level | 23 | (26) | 57 | (30) | 88 | (25) | 11 | (9) |
Procurement for other vector-borne diseases at central level | 41 | (27) | 55 | (29) | 77 | (22) | 10 | (10) |
Procurement of vector control pesticides at decentralized level | 71 | (28) | 72 | (29) | 75 | (24) | 50 | (10) |
Only WHO recommended products procured at central level | 81 | (27) | 87 | (30) | 68 | (25) | 29 | (7) |
Only WHO recommended products procured at decentralized level | 76 | (21) | 50 | (20) | 35 | (17) | 40 | (5) |
WHO quality standards used for centralized procurement | 82 | (28) | 100 | (30) | 80 | (25) | 33 | (6) |
WHO quality standards used for decentralized procurement | 68 | (19) | 52 | (21) | 39 | (18) | 40 | (5) |
Data presented as % of responding countries per Regional Group that gave a positive response regarding each topic (n indicates number of responding countries for each topic) |
Vector control spraying operations could adversely affect the health of spray workers, but health risks are reduced when adequate safety precautions are taken, for example, by using personal protective equipment. National guidelines or training curricula for safety precautions or risk reduction of spray workers for vector control operations were reportedly available in 70% of countries in the African, Asia-Pacific and Latin American & Caribbean Groups (Table 4). However, national guidelines for health monitoring of spray workers in vector control operations (e.g. to detect signs and symptoms of pesticide poisoning) were present in only 11–44% of countries, depending on the region (Table 4), suggesting a major deficiency in health monitoring.
In countries where vector control operations were delegated or contracted to the private sector or to NGOs, these operations were monitored by the Ministry of Health in only part of the countries, suggesting that that there were many delegated or contracted vector control operations that were not monitored by the health authorities (Table 4).
Furthermore, it was reported that those responsible for decision-making and implementation of vector control activities received certified training in vector control in only a minority of countries, which indicates a deficiency in capacity building (Table 4).
Pest control operators (PCOs) are private sector companies engaged in the control of domestic and peri-domestic pest problems, including insect pests. In part of countries in each region, PCOs were required to be licensed or certified (Table 4); licensing may or may not have involved specific training for PCO staff.
Table 4
Status of application of vector control insecticides
| African | Asia-Pacific | Latin American & Caribbean | European & Others |
Topic | % | (n) | % | (n) | % | (n) | % | (n) |
Guidelines for safety precautions of vector control spray workers | 71 | (28) | 70 | (30) | 71 | (24) | 56 | (9) |
Guidelines for health monitoring of vector control spray workers | 29 | (28) | 27 | (30) | 44 | (25) | 11 | (9) |
Delegated vector control operations adequately monitored | 67 | (18) | 54 | (13) | 56 | (9) | 50 | (6) |
Vector control decision-makers trained in vector control | 44 | (27) | 38 | (29) | 36 | (25) | 25 | (8) |
Pest control operators required to be licensed or certified | 65 | (26) | 63 | (30) | 56 | (25) | 88 | (8) |
Data presented as % of responding countries per Regional Group that gave a positive response regarding each topic (n indicates number of responding countries for each topic) |
Vector control operations in which insecticides are used depend on a functional infrastructure for safe and secure transport and storage of insecticides and equipment. However, adequate, safe, and secure facilities for storing vector control insecticides at periphery level were available in only half of the countries and were least common in the Latin American & Caribbean Group (Table 5). Moreover, stock keepers at periphery level with adequate training on stock management were lacking from a substantial proportion of countries across regions (Table 5). In only a minority of countries across regions it was required that the transport of vector control insecticides to stores or points-of-use was accompanied by a person trained on safe transport and emergency procedures (Table 5).
At the end of spray operations, empty insecticide containers (e.g. tins, flasks, sachets) should be safely disposed, to avoid their reuse or refilling, and rinsate (liquid used to rinse containers) should be reused [16]. However, most countries across regions lacked a national guidance document on the safe and environmentally sound disposal of pesticide containers (Table 5).
Pesticides become obsolete after having expired, when their contents or packaging have deteriorated, when they are no longer needed for vector control, or when they have become de-registered or banned. Accumulation of obsolete vector control insecticides was reportedly a problem in many countries in the African, Asia-Pacific and Latin American & Caribbean Groups, but not in the European & Others group (Table 5).
Table 5
Status of storage, transport, and disposal of vector control insecticides
| African | Asia-Pacific | Latin American & Caribbean | European & Others |
Topic | % | (n) | % | (n) | % | (n) | % | (n) |
Secure pesticide storage facilities at periphery level | 46 | (28) | 55 | (29) | 24 | (25) | 67 | (9) |
Trained pesticide storekeepers at periphery level | 60 | (25) | 50 | (30) | 65 | (23) | 67 | (9) |
Pesticide transport personnel trained on safety, emergency | 41 | (27) | 37 | (30) | 40 | (25) | 33 | (9) |
Guidance on sound disposal of vector control pesticide containers | 46 | (28) | 48 | (29) | 24 | (25) | 22 | (9) |
Accumulation of obsolete vector control insecticides not a problem | 56 | (27) | 60 | (30) | 48 | (25) | 100 | (10) |
Data presented as % of responding countries per Regional Group that gave a positive response regarding each topic (n indicates number of responding countries for each topic) |
At institutional level, a national vector control unit, or body, with the responsibility for all vector control activities, was reportedly in place in most countries across regions, except for the European & Others Group (Table 6).
The International Code of Conduct on Pesticide Management (‘Code of Conduct’) provides a framework for governments to manage pesticides throughout their lifecycle [10]. A small majority of countries reported that their Ministry of Health used, or referred to, the Code of Conduct in the management of public health pesticides. An exception were countries in the European & Others Group where the Code of Conduct had reportedly not been used for public health pesticides (Table 6).
In some countries, the central-level Ministry of Health did not have available records on the use of vector control insecticides, suggesting that the authorities may not keep track of the amounts and types of insecticides used in the country (Table 6).
Table 6
Policy and institutional aspects of vector control
| African | Asia-Pacific | Latin American & Caribbean | European & Others |
Topic | % | (n) | % | (n) | % | (n) | % | (n) |
National vector control unit in place | 82 | (28) | 70 | (30) | 88 | (25) | 30 | (10) |
Use of Code of Conduct for public health pesticides | 78 | (27) | 69 | (29) | 54 | (24) | 11 | (9) |
Records available on use of vector control insecticides | 71 | (28) | 82 | (28) | 80 | (25) | 44 | (9) |
Data presented as % of responding countries per Regional Group that gave a positive response regarding each topic (n indicates number of responding countries for each topic) |