The World Health Organization (WHO) has unveiled a new initiative aiming to stop the further spread of Anopheles stephensi (An. stephensi) in Africa. An. Stephensi is an invasive mosquito species identified by WHO as being a ‘significant threat’ to malaria control and elimination.
Originally native to parts of South Asia and the Arabian Peninsula, An. stephensi has increased its range over the last decade, WHO outlined, and has been found in Djibouti, Ethiopia, Sudan, Somalia and Nigeria.
However, unlike the other main mosquito vectors of malaria in Africa, An. stephensi thrives in urban settings. This has raised concerns about the impact the species could have on the control and elimination of malaria in the region, as more than 40% of the population in Africa live in urban environments.
“We are still learning about the presence of An. stephensi and its role in malaria transmission in Africa,” said Dr Jan Kolaczinski, who leads the Vector Control and Insecticide Resistance unit with the WHO Global Malaria Programme. “It is important to underscore that we still don’t know how far the mosquito species has already spread, and how much of a problem it is or could be.”
WHO’s new initiative aims to support an effective regional response to An. stephensi on the African continent through a five-pronged approach, including increasing collaboration across sectors and borders, as well as strengthening surveillance to determine the extent of the spread of An. stephensi and its role in transmission.
The initiative also includes improving information exchange about the presence of An. stephensi and efforts to control it, developing guidance for national malaria control programmes about appropriate ways to respond to An. stephensi and prioritising research to evaluate the impact of interventions and tools against An. stephensi.
In a statement, WHO recommended that, where feasible, national responses to An. stephensi should be integrated with efforts to control malaria and other vector-borne diseases, such as dengue fever, yellow fever and chikungunya.
Dr Ebenezer Baba, malaria advisor for the WHO African Region, said: “Integrated action will be key to success against An. stephensi and other vector-borne diseases. Shifting our focus to integrated and locally adapted vector control can save both money and lives.”