Background: Phlebotomus papatasi (Diptera: Psychodidae) is the main vector of zoonotic
cutaneous leishmaniasis. Wolbachia is a symbiotic alphaproteobacteria of arthropods that can be involved in susceptibility or resistance. This study aimed to investigate the relationship between Wolbachia and
Deltamethrin susceptibility/resistance in Ph. papatasi.
Deltamethrin filter papers (0.00002%) were used to test sand fly field collected from southern Iran. After the test, PCR amplification of the Wolbachia
surface protein gene (wsp) was used to measure Wolbachia
infection rate in the killed, surviving, and control groups. Result: The rates of
infection by Wolbachia strain (wPap, super group A) differed between killed (susceptible) and surviving (resistant) Ph. papatasi specimens. The rate of Wolbachia
infection in susceptible individuals was more than twice (2.3) (39% vs. 17%) in resistant individuals with the same genetic background. This difference was highly significant (p < 0.001), indicating a positive association between Wolbachia
infection and susceptibility to
Deltamethrin. In addition, the results showed that
Deltamethrin can act as a PCR inhibitor during detection of Wolbachia in Ph. papatasi. Conclusion: Results of this study show that Wolbachia is associated with
Deltamethrin susceptibility level in Ph. papatasi. Also, as
Deltamethrin has been identified as a PCR inhibitor, great care must be taken in interpreting Wolbachia
infection status in infected populations. The results of this study may provide information for a better understanding of the host-symbiont relationship, as well as application of host symbiosis in pest management.