Prevention and Control Measures
Prevention and control measures directed at the reduction of vector density are fundamental, and if effective, can prevent transmission.
An effective and operational Integrated Management Strategy for the Prevention and Control of Dengue (IMS –Dengue) provides the basis for adequate preparedness to Zika virus. In the current situation, the intensification of comprehensive prevention and control of IMS-dengue is recommended. These recommendations include:
- Intersectoral participation and collaboration at all levels of government and of health, education, environment, social development and tourism agencies.
- Participation of non-governmental organizations (NGOs) and private organizations; at the same time, control programs must maintain risk communication and mobilize the whole community.
Mosquito control is the only measure that can interrupt the transmission of vector borne viruses, such as dengue, Zika, and chikungunya. Due to the importance of vector control, the key elements of a vector control program that should guide the response are listed below.
Integrated Vector Management (IVM)
An effective and operational dengue and chikungunya vector control program provides the basis for adequate preparation against Zika virus, because these viruses are transmitted by the same mosquito, Ae. Aegypti. Therefore, it is recommended to apply and intensify the surveillance and vector control measures developed for dengue and chikungunya as part of the Integrated Vector Management (IVM).
To ensure its success, it is key to include intersectoral participation and collaboration at all levels of government, including the health, education, environment, social, development and tourism sectors, among others. IVM is also relies on support of non-governmental organizations (NGOs) and private organizations; communication channels must remain open and community participation should be mobilized. It is important to provide clear and quality information to the public about these diseases via communication campaigns.
To ensure its success, it is key to include intersectoral participation and collaboration at all levels of government, including the health, education, environment, social, development and tourism sectors, among others. IVM is also relies on support of non-governmental organizations (NGOs) and private organizations; communication channels must remain open and community participation should be mobilized. It is important to provide clear and quality information to the public about these diseases via communication campaigns.
Given the broad distribution of Ae. aegypti and Ae. albopictus in the Americas, prevention and control measures should be aimed at reducing vector density, and obtaining the acceptance and collaboration of communities in adopting such measures.
Prevention and control measures by national authorities should include the following:
- Strengthening environmental management to prevent or minimize vector propagation and human contact with the vector-mosquito by eliminating vector breeding sites in each household and in common areas of districts and cities (e.g., parks, schools, cemeteries, etc.).
- Organizing mass sanitation campaigns for the elimination of breeding sites, specifically in areas where routine garbage collection has been interrupted.
- Implementing breeding site control measures by applying physical, biological and chemical methods, while actively involving families and communities.
- Identifying areas of high risk of transmission (risk stratification), and prioritizing those where people concentrate (e.g., schools, transport terminals, hospitals, health centers, etc.). Mosquitoes should be removed with a radius of at least 400 meter around these facilities.
- In areas where autochthonous or imported cases of dengue, chikungunya, and/or Zika virus are detected, it is suggested to use adulticide treatment (primarily through spraying), to remove infected adult mosquitoes and interrupt transmission. It is important to take into account that this action is exceptional and is only effective when executed by adequately trained personnel following internationally accepted technical guidelines and when carried out together with other proposed actions, as described above. Spraying is the primary manner to intensively interrupt transmission and obtain time to consolidate the removal of larval breeding sites.
- Selecting appropriate insecticide (in accordance with PAHO/WHO recommendations), verifying the product label and formula, and considering the susceptibility of mosquito populations to that insecticide.
- Maintaining and using spraying equipment in an appropriate manner and maintaining a stockpile of insecticides.
- Ensuring intensified monitoring (e.g., quality control) of fieldwork operators both during larval control and during adult insecticide treatment (fumigation).
Integrated (simultaneous or coordinated) actions for vector control, in space and time, (e.g., adulticide and larval control by trained personnel, coupled with sanitation and the promotion of community actions) are essential to achieve the greatest impact in the shortest amount of time.
It is crucial that the personnel involved in the actions of chemical control use, without exception, the appropriate personal protective equipment for this activity. It is the responsibility of vector control programs to supply this equipment to its staff, to audit its use, and to have enough stockpile stored under appropriate conditions.