RT-PCR quantitativa para detecção de DENV em larvas de Aedes SP

Abstract

Dengue virus 1 to 4 (family Flaviviridae, genus Flavivirus) (DENV-1, 2, 3, 4), are responsible for an estimated 50 million cases annually. Infections caused by any of the four serotypes can cause an acute febrile illness and a more serious, often fatal, characterized by hemorrhage and shock syndrome. The virus is mainly transmitted by Aedes aegypti and Aedes albopictus, when DENVinfected, transmit the virus to the host at the time of blood meal. Mosquitoes may acquire the virus by biting an infected person, male to female (venereal transmission) and through the progeny. Vertical transmission occurs only when the virus multiplies in the ovariole of the female and infected eggs. Because there is no specific therapy, the most effective method of disease control is direct combat the vector. In addition, there are few studies addressing vector competence, which is the ability to infect mosquitoes, and to keep replicating the virus spread. Why this study was to evaluate the viral load of DENV pools of Aedes sp collected in Belo Horizonte-MG. The evaluation was done by amplification of DNA from the 5'UTR region of DENV and the control of glutamine synthetase gene from Aedes sp by qPCR. To develop this technique was tested a mixture composed of reagents that detect and amplify DENV allowed in pool of larvae and even a single larva. To determine the number of copies of DENV by larvae, additional tests should still be made. Thus, the results of this study indicate that it was possible to detect, through a more sensitive technique, DENV on Aedes sp, and with prospects for a quantification of the numbers of copies. Studies using this methodology will be important to assess vector competence, stating, on the numbers of infected larvae, the risk of dengue transmission in a given area and thus assist in the control and prevention of dengue in Brazil.