In that time, the CDC announced a definitive relationship between Zika and microcephaly based on the timing, the virus in fluids and tissues, antibodies against the virus in the brains of these babies with small heads, and studies of cases and non-cases.
"When the CDC comes and validates that, it's very comforting to say, okay, this is not something crazy that we were thinking about," says Dr. Marques.
And it seems the virus has a propensity for nerve cells.
"Eye problems, hearing problems, so the microcephaly in the end, may be just the tip of the iceberg of all congenital disease that Zika can cause," he says.
Dr. Marques says a review of the records reveals more cases of Zika than originally thought.
He has been working on a natural history study. In other words, what happens to you when you contract the illness? More than 300 people are included so far with symptoms of fever and rash, but making note of the first few days isn't enough when problems can occur months later.
Other questions -- are there other types of mosquitos that can carry the virus, and how large of a role does sexual transmission play?
When he left for Brazil, he wondered what could be done for the women who are pregnant in the midst of the outbreak.
"They get really annoyed when people come to them and say, 'You've got to be really careful.' It makes them even more nervous. For some women, if they felt they had Zika, they don't want to know if the baby... they just don't want to know," he says. "A lot of mosquito repellent was provided to pregnant women, so they could protect themselves, but I think this is too little."
He raises the possibility of ongoing nerve cell damage in the microcephalic babies. If the virus stays hidden to reemerge later, this has greater implications for the babies' development and for infected adults.
"In adults, for the sake of safety of blood supply," he says.
Dr. Marques says two questions need to be answered at this point. 1.) How common is Zika in the population? That's tricky because common tests cross react with dengue, a related virus. And, 2.) Does having tht Zika infection make you immune, or could you get it again? Recent observations hint that it's not as straightforward as with other viruses.
"If there is no immunity induced by infection, it implies the vaccine development will be harder," he adds.
for more features.