“This epidemic is an unfolding story,” said Dr. Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases. “As with Ebola, this virus is something that could exist for years under the radar, and we don’t know until we get thousands of cases what it really does.”
“With Zika, we’re seeing new twists and turns every week.”
To doctors in Recife, whatever was striking the babies seemed to have fallen like a bolt from the blue.
In reality, it had been building for months. It had even been frequently discussed among clinicians — but no one had realized what was on the horizon.
Seeing the Same Symptoms
A year earlier, doctors say, the first patients had started trickling into public hospitals in Natal, capital of the state of Rio Grande do Norte, about 200 miles up the coast from Recife.
It was a few weeks after the 2014 World Cup, and Natal had been one of the host cities of the soccer championship, which draws fans from all over the world.
Many patients lived on the city’s margins, others in settlements dotted across the sert?o, northeast Brazil’s arid hinterland.
Almost all had the same symptoms: a flat pinkish rash, bloodshot eyes, fever, joint pain and headaches. None were desperately ill, but the similarities were striking.
“That scared some patients and doctors, and my team,” said Aline Bezerra, a nurse and the municipal epidemiologist. “We knew nothing other than that it might be some kind of light dengue.”
Tests ruled that out, along with other common viruses, but the patients kept coming. One day in January 2015, 100 showed up at the state’s hospitals.
“We alerted the federal authorities that we were dealing with something urgent and new,” said Dr. Kleber Luz, an infectious diseases specialist at the Federal University of Rio Grande do Norte. “But their reaction was sluggish.”
By last March, the spread of a “doen?a misteriosa” — the mystery disease — had become impossible to ignore. It appeared in two more states nearby. Then it reached Salvador, a city of 2.5 million.
Doctors speculated that it was an allergy; that it was roseola, a childhood illness; that it was a new variant of Fifth Disease, a facial rash that gives children a “slapped-cheek” look.
“People were claiming it was polluted water,” said Dr. G?bio Soares, a virologist at the Federal University of Bahia in Salvador. “I began thinking it was something transmitted by mosquitoes.”
Working in his modest lab with a colleague, Dr. Silvia Sardi, Dr. Soares kept testing blood samples.
Other doctors were doing the same. Over 6,800 samples were tested, according to news reports, from victims ranging from 4 months to 98 years old. Parvovirus, dengue, chikungunya and other suspects were all ruled out.
Finally, in April, Dr. Soares and Dr. Sardi were sure: It was Zika.
“I actually felt a sense of relief,” Dr. Soares said. “The literature said it was much less aggressive than viruses we already deal with in Brazil.”