A method of controlling a pathogenically infected mosquito is disclosed. The method comprising administering to a larva of a mosquito an isolated nucleic acid agent comprising a nucleic acid sequence which specifically downregulates an expression of at least one mosquito pathogen resistance gene product of the mosquito, wherein downregulation of the expression of the at least one mosquito pathogen resistance gene in the larvae renders an adult stage of the mosquito lethally susceptible to the pathogen, thereby controlling the pathogenically infected mosquito.