The Ghana Health Service has received confirmation of the presence of a new mosquito vector (Anopheles stephensi), in the country.
The new vector was confirmed in March 2023, from samples taken in Tuba and
Dansoman, in the Greater Accra region, as part of the routine malaria surveillance system and vector control monitoring done across the country through designated sentinel sites.
The World Health Organization, in 2019, issued an alert on the invasion of Africa by a malaria-transmitting new mosquito vector (Anopheles stephensi). Until 2011, the reported distribution of Anopheles stephensi was confined to certain countries of South Asia and parts of the Arabian Peninsula.
Since then, the vector has been identified in Djibouti (2012), Ethiopia (2016), Sudan (2016), Sri Lanka (2017), Somalia (2019), and most recently Nigeria (2020) and Yemen (2021).
Anopheles stephensi is a unique vector known to breed in a myriad of sources such as ponds, swamps, marshes, artificial containers, and other man-made container spots. It can practically breed in almost all
water sources, some of which are not the traditional breeding sites of the common Anopheles species, particularly in urban areas.
The vector also survives in extremely high temperatures during the dry season
when malaria transmission usually declines.
It is known to spread fast and adapt to different climatic conditions posing challenges to its control.
As a response to this finding, a task force has been formed to advise and coordinate the following needed actions.
1. Enhance larval source management nationwide, especially where Anopheles stephensi were detected.
2. Enhance vector surveillance on Anopheles stephensi per the updated vector control guideline.
3. Improve the country’s laboratory and human capacity to identify Anopheles stephensi.
4. Collaborate with WHO to update the Vector Map.
5. Intensify community engagement and sensitization at all levels.