Multiple insecticide resistance mechanisms involving metabolic changes and insensitive target sites selected in anopheline vectors of malaria in Sri Lanka

Table 7 Insecticide cross-resistance spectra and prevalence of resistance mechanisms in different An. culicifacies populations.

	DDT	Pro	Mal	Fen	λ-cy	Per	Del	Cyp	Cyf	Eto	CE	GST	Mono	aAChE	MCE
Anuradhapura	RR	SS	RR	RS	SS	RS	SS	SS	SS	RS	+	++	+	++	++
Kurunegala	RR	SS	SS	SS	SS	RS	SS	SS	SS	RS	+	++	+	+	-
Moneragala	RR	SS	RR	RS	SS	RS	RS	SS	SS	RS	+	+	+	+	++
Puttalam	RR	SS	RR	SS	SS	RS	SS	SS	SS	RS	++	++	+	++	++
Trincomalee	RR	SS	RR	RS	SS	RR	RS	SS	SS	RS	+	+++	++	++	+++

SS = susceptible (< 10 R)
RS = intermediate (10–50% R)
RR = resistant (> .50% R) (According to Herath, 1997)
Pro = propoxur
Mal = malathion
Fen = fenitrothion
λ-cy = λ-cyhalothrin
Del = deltamethrin
Per = permethrin
Cyp = cypermethrin
Cyf = cyfluthrin
Eto = etofenprox
CE = carboxylesterase
GST = glutathione S-transferase
Mono = monooxygenase
MCE = malathion carboxylesterase
aAChE = altered acetylcholinesterase
+ = mechanism present at low level, ++ = mechanism present at moderate level, +++ = mechanism present at high level - = absence of mechanism

ISSN: 1475-2875