Keila Maia / Fiocruz MG
From the left, Jeffrey Berthony, immunologist and researcher at Fiocruz Minas and George Washington (GWU), Flávia Ribeiro, infectious agent and researcher at the Research Center of Hospital das Clínicas, and David Diemert, infectious disease specialist and professor at GWU (Photo: Fiocruz Minas)
Researchers of the Hospital das Clínicas of the Federal University of Minas Gerais (UFMG), George Washington University (USA) and Fiocruz Minas are participating in a large phase II/IIb clinical trial of an experimental vaccine against zika virus infection in Belo Horizonte. Made with part of the genetic material of the virus, the vaccine may produce antibodies capable of promoting a response against infection in an individual who is immunized.
Called "DNA vaccine against zika", the experimental substance has already been tested in humans in the USA, and the clinical trial has been approved by ethics committees and national and international regulatory agencies. It will now be evaluated in an expanded population for the purpose of studying new data on its efficacy and safety. For this new phase, healthy volunteers aged between 15 and 35 years, living in Belo Horizonte or Metropolitan Region and who are willing to participate in the study for the next two years will be recruited.
The volunteers will be selected after a clinical evaluation and laboratory tests that will be offered free of charge by the team of Hospital das Clínicas. Fiocruz Minas will be responsible for processing blood and urine of all the participants of the research, who will be tested to evaluate the effectiveness, immune response, and effects of the vaccine in the body.
“We will process and store the samples of participants. One of the purposes of the study is to verify if the vaccine induces antibodies that protect against zika virus," explains the researcher and coordinator of the study at Fiocruz Minas, Rodrigo Corrêa Oliveira.
In order to be able to perform the processing of samples, professionals from the Group of Molecular and Cellular Immunology of Fiocruz Minas underwent rigorous training and received an international certificate, enabling them to perform this type of work. "It is an activity that involves a series of protocols to be followed, and therefore, it requires a thorough preparation. In Brazil, very few people are allowed to develop this kind of sample processing," says the researcher Jeffrey Michael Bethony, from George Washington University, who has been developing projects in partnership with Fiocruz Minas as a visiting researcher for 15 years.
The study is led by the National Institute of Allergy and Infectious Diseases of the National Institutes of Health (NIH), an organization of the American government. In Minas Gerais, the research is coordinated by ID specialist Flávia Ribeiro, chief researcher and technical coordinator of the Clinical Research Center of Hospital das Clínicas, UFMG.
Zika is an acute viral disease, mainly transmitted by mosquitoes such as Aedes aegypti. Symptoms may include a rash accompanied by severe itching, as well as intermittent fever, non-purulent and pruritus-free conjunctival hyperemia (red and watery eyes), joint pain, muscle pain, and headache. The disease develops benign, and the symptoms usually disappear spontaneously after three to seven days.
However, although zika virus infection can go away without causing major disorders, confirmed cases of microcephaly indicate that the mothers were infected with the virus in the first months of pregnancy. The child is considered to have microcephaly when her/his head circumference is smaller than 32 cm. Studies also indicate a link between zika and Guillain-Barré syndrome, an autoimmune disease that causes muscle weakness and paralysis, which can put a patient's life at risk in more severe cases.
There is still no cure or vaccine to prevent infection by zika. The main prevention measure currently is the control of disease-transmitting mosquitoes.