VERTICAL TRANSMISSION OF DENGUE VIRUS ON FIELD MOSQUITOES IN BANYUMAS REGENCY, CENTRAL JAVA, INDONESIA
Background: The role of vertical transmission on the dengue virus (DENV) transmission is still under research. Some researcher believed that vertical transmission play an important role on DENV persistence in nature. However, still a few reports showed vertical transmission on the field mosquitoes and its importance. This study aims to detect the vertical transmision on field mosquitoes in Banyumas Regency, Central Java, Indonesia using immunohistochemistry (IHC) assay and Reverse-Transcriptase Polymerase Chain Reaction (RT-PCR).
Materials and Methods: 100 houses were chosen in each of three dengue endemic villages, resulting in a total of 300 houses for ovitrap installations. Six days after initial installation, eggs were then collected from ovistrips and grown in a rearing room to adulthood. Caputs of Fillial 1 from adults mosquitoes were assesed using IHC assay, while thorax part were assesed using RT-PCR.
Result: Based on IHC assay, all of the studied villages showed the occurence of vertical transmission with percentage around 13-27%. Ae. aegypti showed higher percentage of vertical transmission than Ae. albopictus. There is a discrepancy results based on RT-PCR assay since there is no positive band detected on electrophoresis gel indicated negative of dengue virus.
Conclusion: The discrepancy results between IHC and RT-PCR is an interesting facts to be explored, due to the specificity and sensitivity of IHC. Even though there is no positive band on electrophoresis gel from RT PCR assay showed that negative result of DENV detection on the studied samples, with respect to positive results confirmation based on IHC assay, it should be an awareness to the health officer to prevent and control DENV tranmission.Keywords: dengue virus, Aedes sp, vertical tranmission, RT-PCR, Indonesia