A tool box for operational mosquito larval control: preliminary results and early lessons from the Urban Malaria Control Programme in Dar es Salaam, Tanzania
1 Durham University, School of Biological and Biomedical Sciences, South Road, Durham DH13LE, UK
2 Dar es Salaam City Council, Ministry of Regional Administration and Local Government, United Republic of Tanzania
3 Swiss Tropical Institute, Department of Public Health and Epidemiology, PO Box, 4002 Basel, Switzerland
4 University of Freiburg, Department of Physical Geography, Freiburg, Germany
5 Ifakara Health Research and Development Centre, Coordination Office, PO Box 78373, Kiko Avenue, Mikocheni, Dar es Salaam, United Republic of Tanzania
6 Ministry of Agriculture and Food Security, Dar es Salaam, United Republic of Tanzania
7 Kenya Medical Research Institute, PO Box 54840, Nairobi, Kenya, Africa
8 Office of Population Research, Princeton University, Princeton, NJ08544, USA
9 Harvard School of Public Health, Department of Population and International Health, 665 Huntington Avenue, Boston, MA 02115, USA
Malaria Journal 2008, 7:20 doi:10.1186/1475-2875-7-20Published: 25 January 2008
As the population of Africa rapidly urbanizes, large populations could be protected from malaria by controlling aquatic stages of mosquitoes if cost-effective and scalable implementation systems can be designed.
A recently initiated Urban Malaria Control Programme in Dar es Salaam delegates responsibility for routine mosquito control and surveillance to modestly-paid community members, known as Community-Owned Resource Persons (CORPs). New vector surveillance, larviciding and management systems were designed and evaluated in 15 city wards to allow timely collection, interpretation and reaction to entomologic monitoring data using practical procedures that rely on minimal technology. After one year of baseline data collection, operational larviciding with Bacillus thuringiensis var. israelensis commenced in March 2006 in three selected wards.
The procedures and staff management systems described greatly improved standards of larval surveillance relative to that reported at the outset of this programme. In the first year of the programme, over 65,000 potential Anopheles habitats were surveyed by 90 CORPs on a weekly basis. Reaction times to vector surveillance at observations were one day, week and month at ward, municipal and city levels, respectively. One year of community-based larviciding reduced transmission by the primary malaria vector, Anopheles gambiae s.l., by 31% (95% C.I. = 21.6–37.6%; p = 0.04).
This novel management, monitoring and evaluation system for implementing routine larviciding of malaria vectors in African cities has shown considerable potential for sustained, rapidly responsive, data-driven and affordable application. Nevertheless, the true programmatic value of larviciding in urban Africa can only be established through longer-term programmes which are stably financed and allow the operational teams and management infrastructures to mature by learning from experience.