By December 2018, questionnaire responses had been received from 94 countries, indicating a response rate of 48% (Figure 1). The response rate was 54%, 55%, 76% and 19%, respectively, from the African, Asia-Pacific, Latin American & Caribbean, and European & Others regions.
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 (68-80%) across regions (Table 1). An exception was the European & Others Region where the capacity for testing was less common (30% of responding countries), a result which is in line with the region’s low incidence of vector-borne diseases in recent history. Representative sentinel sites, needed for monitoring of temporal changes in the prevalence of resistance, had been established in 36-57% of the countries in the Africa, Asia-Pacific and Latin American & Caribbean regions (Table 1). Insectaries to support insecticide susceptibility testing and efficacy testing were reported to be in place in 40-68% of countries across regions. Capacity for molecular testing and biochemical testing was reported from few countries but was most common in the African Region (36-39% of countries) (Table 1). Out of the 25 countries that reported the presence of molecular testing capacity, 20 also reported the presence of biochemical testing capacity. In total, 24 out of 25 countries with molecular testing and 23 out of 24 countries with biochemical testing also reported that capacity for susceptibility testing was in place. This suggests that molecular and biochemical testing were not used on their own, but together, and in combination with susceptibility testing. Furthermore, out of a total of 93 responding countries, 14 reported having all components (i.e. susceptibility testing, sentinel sites, insectaries, molecular and biochemical testing) in place.
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 region 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. Some 80-92% of all countries in the Asia Pacific, African and Latin American & Caribbean regions claimed that insecticide susceptibility was factored into the procurement process (Table 2). Despite this, a smaller percentage (68-80%) had capacity for insecticide susceptibility testing in place (see Table 1). Out of a total of 75 countries that used insecticide susceptibility status as criterion in the procurement process, 17 countries did not have susceptibility testing capacity. This suggests that the procurement requirements could not be fulfilled everywhere, unless some countries sent entomological samples for testing abroad.
A small fraction of countries (8-27%) 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 (11-40%) experienced problems estimating the amounts needed for emergency situations (e.g. disease outbreaks), particularly in the African and Asia-Pacific regions.
In 73% of 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 (0-56% of countries), suggesting that in many countries the quality of procured consignments was not guaranteed. Pesticide procurement may benefit from regional collaboration, for example, by combining the procurements of minor-use products between neighbouring countries to reduce costs. In this regard, 52% of countries in the Latin American & Caribbean Region 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 (20-32%) (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 region that gave a positive response regarding each topic (n indicates number of responding countries for each topic)
|
Most countries (63-84%), except in the European & Others Region, reported that the Ministry of Health procured pesticides for malaria control at central level (Table 3). Fewer countries in the African and Asia-Pacific regions reported central-level pesticide procurement for arboviral diseases (23-57%) and other vector-borne diseases (41-55%) (Table 3). The presence of central-level procurement does not mean that all vector control insecticides were procured that way. In 50-75% of countries there were other agencies or authorities apart from the central-level procuring agency, that procured pesticides for vector control (Table 3). These agencies or authorities, as reported by 69 countries, were local authorities, the private sector, donor-funded projects, and ministries other than Health (Table 4). In the African Region, the private sector and donor-funded projects (e.g. the U.S. President’s Malaria Initiative) were the most commonly reported procuring agencies apart from the Ministry of Health. Local authorities were the most common procuring agencies besides the central Ministry of Health in the Asia-Pacific and Latin American & Caribbean regions, reported from 48% and 67% of countries, respectively (Table 4). 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 81-87% of countries in the African and Asia-Pacific regions, 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 (35-76% of countries) (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 by agencies other than at central 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 by other agencies
|
76
|
(21)
|
50
|
(20)
|
35
|
(17)
|
40
|
(5)
|
Data presented as % of responding countries per region that gave a positive response regarding each topic (n indicates number of responding countries for each topic)
|
Table 4 Agencies other than the national-level health ministry that procured vector control insecticides
Agency
|
African (n=19)
|
Asia-Pacific (n=21)
|
Latin American & Caribbean (n=18)
|
European & Others (n=5)
|
Local authorities
|
26
|
48
|
67
|
80
|
Private sector
|
53
|
33
|
22
|
20
|
Donor-funded projects
|
37
|
10
|
22
|
0
|
Ministries other than Health
|
11
|
19
|
17
|
0
|
Data presented as % of responding countries per region (n indicates number of responding countries per region)
|
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 70-71% of countries in the African, Asia-Pacific and Latin American & Caribbean regions (Table 5). 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 5), suggesting a major deficiency in health monitoring. Out of a total of 28 countries with guidelines on health monitoring, 26 also had guidelines on safety precautions in place. It remains unknown to what extent these guidelines were implemented, and who implemented them.
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 50-67% of the countries, suggesting that there were many delegated or contracted vector control operations that were not monitored by the health authorities (Table 5).
Furthermore, it was reported that those responsible for decision-making and implementation of vector control activities received certified training in vector control in only 25-44% of countries, which indicates a deficiency in capacity building (Table 5).
Pest control operators (PCOs) are private sector companies engaged in the control of domestic and peri-domestic pest problems, including insect pests. In 56-88% of countries across regions, PCOs were required to be licensed or certified (Table 5); licensing may or may not have involved specific training for PCO staff.
Table 5 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 region 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 24-67% of the countries and were least common in the Latin American & Caribbean Region (Table 6). Moreover, stock keepers at periphery level with adequate training on stock management were lacking from 33-50% of countries across regions (Table 6). In a 33-41% 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 6).
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 (mixture of pesticide with water resulting from cleaning of containers) should be reused [16]. However, 52-88% of countries across regions lacked a national guidance document on the safe and environmentally sound disposal of pesticide containers (Table 6).
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 40-52% of countries in the African, Asia-Pacific and Latin American & Caribbean regions, but not in the European & Others Region (Table 6).
Table 6 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 stock keepers 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 region 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, with the responsibility for all vector control activities, was reportedly in place in 70-88% of countries across regions, except for the European & Others Region, where it was reported from only 30% of countries (Table 7).
The International Code of Conduct on Pesticide Management (‘Code of Conduct’) provides a framework for governments to manage pesticides throughout their lifecycle [10]. A 54-78% 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 was the European & Others Region where the Code of Conduct had reportedly not been used for public health pesticides in 8 out of 9 countries (Table 7).
In 18-56% of 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 7).
Table 7 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 region that gave a positive response regarding each topic (n indicates number of responding countries for each topic)
|