The world needs to work better and collaborate with sectors beyond health to implement the Global Vector Control Response 2017–2030 (GVCR), which aims to prevent and control diseases that are transmitted by vectors, particularly mosquitoes.
"It is time that vector control programmes work jointly with city planners, environmentalists, engineers and sectors that manage water and sanitation," said a leading expert during a WHO-hosted webinar on Reducing the burden and threat of vector-borne diseases to achieve the NTD road map targets, "as we face the prospect of 7 out of 10 people living in cities and urban areas globally by 2050".
"One of the things which is critical as we build out future cities … we really need to do better in the area of prevention … reducing the habitats of all mosquito species," said Steve Lindsay, panellist and former Professor at Durham University, United Kingdom.
This implies reducing the breeding sites for Aedes mosquitoes that transmit vector-borne diseases such as dengue, chikungunya and malaria by enhancing access to piped water, constructing houses with built-in screens to block mosquito entry, clearing waste, improving drainage and keeping the environment clean.
These measures, as advocated by GVCR, can be implemented in present-day towns and smaller cities that will eventually expand in two to three decades into sprawling cities. So, working locally with city mayors and communities can make a big difference and build resilience in preventing mosquito-borne diseases.
During the webinar, panellists highlighted progress and challenges in implementing GVCR since its launch in 2017. A joint action group is coordinating implementation globally, and many WHO regions have developed vector control policies and strategies.
While the GVCR is on track for some activities, amounting to an almost 10% reduction in global mortality over the past 5 years, for many other activities targets have not been reached, with only 27% of countries completing a vector control needs assessment, well below the 2020 goal of 50%.
Other challenges include lack of entomological capacity, COVID-19 disruptions to programmes and lack of funding to implement GVCR. A progress report outlining achievements and challenges will be submitted to the Seventy-fifth World Health Assembly in May 2022.
Other panelists spoke of vector control in several parts of the world, including in Africa where integrated vector management (IVM) has been pioneered, and in other countries where GVCR has boosted implementation of IVM and increased levels of preparedness against arboviral diseases.
Challenges facing vector control in WHO's Eastern Mediterranean Region were also highlighted. Invasive Aedes aegypti mosquitoes that primarily transmit dengue, chikungunya and yellow fever have spread, and Aedes albopictus is now prevalent in many countries. Much is being done to strengthen surveillance, monitoring and control response with stronger community engagement.
Panellists also spoke of the need to build more entomological capacity. In India, for example, considerable progress has been made with the launch of major government initiatives to eliminate malaria and lymphatic filariasis. The country is poised to defeat visceral leishmaniasis through a reinvigorated vector control and surveillance programme. Furthermore, the Vector Control Research Centre in Puducherry trains several local entomologists through a competitive process but also offers seats to foreign students.
The webinar also heard of progress and challenges in WHO's European and Americas, which are facing increased emergence and re-emergence of vector-borne diseases.
The global spread of vector-borne diseases
More than half the world's population is at risk of infection from vector-borne diseases, especially dengue, leishmaniasis and malaria.
Vector-borne diseases affect more than 1 billion people and cause the death of an estimated 1 million people globally.
Vectors are responsible for transmitting many neglected tropical diseases, mostly among the poorest populations where there is a lack of access to adequate housing, safe drinking-water and sanitation.
Malnourished people and those with weakened immunity are especially susceptible to vector-borne diseases.
During the past two decades, many vector-borne diseases have emerged or re-emerged, spreading to new parts of the world.
Other factors, such as environmental changes, increased international travel and trade, changes in agricultural practices and rapid, unplanned urbanization have facilitated the spread of many vectors worldwide.
Addressing the burden of diseases transmitted by these vectors is critical.
You can access a recording of the full webinar at https://www.youtube.com/watch?v=5OKXvHu_e4U
