ADSL and escherichia coli infection: This observed upregulated AMP expression in response to E. coli in our study is consistent with previous studies where injection of E. coli resulted in the expression of multiple AMPs including defensin, attacin and cecropin thus confirming the strong immunogenic nature of an E. coli infection in tsetse flies (Hao et al., 2001; Boulanger et al., 2002).