House fly
originated in central Asia, the insect expanded its range worldwide long ago as a commensal organism to human populations; the housefly is always found in association [...] confirmed vector for over 100 different pathogens, including viruses (such as the Newcastle Disease virus), bacteria (such as Salmonella and E. coli ), protozoan [...] breeding site to pupate. Flies in the pupal stage are oval-shaped, with bluntly rounded ends, about 8 mm long and change in colour from yellow to red, to