ven before the research was published, Marques was working on the next set of questions in urgent need of answers. Zika no longer presented as the benign virus it appeared to be 70 years ago; it had revealed itself to be complex and capable of harm. Last fall, despite the continued spread of the virus, the World Health Organization declared an end to Zika’s classification as a “Public Health Emergency of International Concern.” But, says Marques, it is hard to define a threat that is still coming into focus. “The hope that Zika is gone,” says Marques, “is not quite right.” Much about the virus remains unknown and—given Zika’s unexpected capabilities to cause serious harm in some cases—research has more to tell us about viral diseases and how to stop them. “All of the easy questions have been answered,” says Marques about Zika. “Now, we’re working on the difficult ones.” One line of inquiry Marques is exploring is why Zika infections can be devastating to some, while others are unaffected. Since arriving in South America, the virus has spread to at least 84 countries, including the United States, but no other population has the same high number of Zika-affected babies as Brazil. Even there, not every infected pregnant woman gives birth to a child with a Zika-related disorder. Why? Marques’s recent lab data have shown that the presence of dengue antibodies can make a Zika infection more severe, both for the initial host and for a fetus that may contract the virus through a mother’s placenta. The process is called antibody-dependent enhancement. If, as Marques suspects, enhancement is playing a role in Zika’s seemingly selective effect, that piece of information will play a vital role in the development of a safe and effective vaccine, while also helping infectious disease specialists to anticipate and prevent new viral epidemics. And that’s at the heart of most infectious disease specialists’ mission—to dig ever deeper, excavating unknowns in pursuit of either stopping diseases before they emerge into deadly epidemics, or stemming their impact. At the Graduate School of Public Health and Pitt’s Center for Vaccine Research, building a global network is a vital component of this work. Labs like the one in Recife—positioned
PHOTO BY LAURA CLARK ROHRER
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Marques and Burke at the Pitt/FIOCRUZ laboratory in Recife, Brazil
Pitt’s Graduate School of Public Health is seizing the momentum. Marques and Burke founded Cura Zika, an international research alliance that targets the epidemic through continued collaboration between researchers at Pitt and FIOCRUZ. at the frontlines of potential outbreaks—can offer researchers a head start in tackling the next emergency. When you’re studying viruses, which are covert and often fast moving, there’s a real advantage to being even one step ahead of the curve. Recently, Marques and his team developed a new, faster, and better way to diagnose Zika, potentially making response to the outbreak and the development of vaccines that much easier. But if there’s any chance of preventing the world’s next Zika epidemic, the research must be done now. Pitt’s Graduate School of Public Health is seizing the momentum. Marques and Burke founded Cura Zika, an international research alliance that targets the epidemic through continued collaboration between researchers at Pitt and FIOCRUZ. “We wanted to do this as a Brazil and U.S. cooperation,” says Burke, who serves as the program director alongside Marques, the scientific director. “This is about their epidemic. The question was, what could we do to help?”
The Cura Zika foundation provides funding for studies across both institutions with efforts that range from research to better understand Zika’s impact on mothers’ placentas to the engineering and evaluation of a Zika vaccine. In recent months, the work of Cura Zika has been highlighted in the New York Times and other media. In 2017, Celina Turchi—a FIOCRUZ epidemiologist who is a scientific advisor with Cura Zika, a close collaborator with Marques, and the senior investigator in the case-control study that linked Zika to microcephaly—was named one of Time magazine’s most influential people of the year. Yet, much about the virus is still unknown. “There are potentially decades more work for us,” says Marques, whose pace remains urgent. These days the Pitt researcher spends most of his time working in his lab, on airplanes, and behind the blinking cursor of journal articles in the making. But no matter where he is, Marques is likely thinking of Zika and Brazil, sifting the possibilities, the knowns and unknowns. ■ S U M M E R
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