ing ▁in ▁Western - style ▁pl aster ed ▁or ▁painted ▁walls , ▁only ▁traditional ▁dwell ings ▁with ▁un p aint ed ▁walls ▁made ▁of ▁mud , ▁st icks , ▁d ung , ▁that ch , ▁cl ay , ▁or ▁c ement . ▁As ▁rural ▁areas ▁of ▁South ▁Africa ▁become ▁more ▁prosper ous , ▁there ▁is ▁a ▁shift ▁towards ▁Western ▁style ▁housing , ▁leaving ▁fewer ▁homes ▁suitable ▁for ▁D DT ▁sp ray ing , ▁and ▁necess it ating ▁the ▁use ▁of ▁alternative ▁insect ic ides . ▁ ▁Other ▁vill agers ▁object ▁to ▁D DT ▁sp ray ing ▁because ▁it ▁does ▁not ▁kill ▁co ck ro aches ▁or ▁bed bug s ; ▁rather , ▁it ▁exc ites ▁such ▁p ests ▁making ▁them ▁more ▁active , ▁so ▁that ▁often ▁the ▁use ▁of ▁another ▁insect ic ide ▁is ▁addition ally ▁required . ▁Py re th roid s ▁such ▁as ▁del t am eth rin ▁and ▁l amb d acy hal oth rin , ▁on ▁the ▁other ▁hand , ▁are ▁more ▁acceptable ▁to ▁residents ▁because ▁they ▁kill ▁these ▁n uis ance ▁insect s ▁as ▁well ▁as ▁mos qu ito es . ▁D DT ▁has ▁also ▁been ▁known ▁to ▁kill ▁benef icial ▁insect s , ▁such ▁as ▁was ps ▁that ▁kill ▁c ater p ill ars ▁that , ▁un checked , ▁destroy ▁that ched ▁roof s . ▁ ▁As ▁a ▁result , ▁Moz amb ique ' s ▁chief ▁of ▁inf ect ious ▁disease ▁control , ▁A vert ino ▁Bar re to , ▁says ▁that ▁resistance ▁to ▁D DT ▁sp