Fig. 3

Estimated precipitation and mean temperature data (a) and specific humidity (b) at Ukaysh, Taiz governorate, Yemen from January 2004 to March 2005 (http://iridl.ldeo.columbia.edu); c Monthly abundance of Anopheles arabiensis (geometric mean number of mosquitoes per house collected by pyrethroid knockdown catch [PKD], with 95 % confidence interval) at Ukaysh (March 2004–March 2005). The red arrow indicates the date (1 Aug 2004) when The National Malaria Control Programme carried out larviciding at all the known larval habitats of Anopheles at this site