 4. High coverage 80 access of Olyset Plus LLIN and high coverage IRS 80 of the household sprayed with pirimiphos methyl CS Randomization of the 48 Muleba clusters into four arms in a factorial design to test for differences in effect between Olyset LLIN and Olyset Plus LLIN and to test for further effect due to IRS with pirimiphos methyl versus no IRS against a background of LLIN use. 