On Zika's trail
The story of the medical detectives who o tracked the deadly disease in Brazil and raised the alarm about the connection between the Zika virus and birth anomalies.
IN a place where the bite of a common mosquito has brought crippling birth defects and early death, they were the detectives sent to gather clues about the crime.
Earlier this year, the four women had been plying the back roads of north- eastern Brazil for days. Their quarry: new mothers who may have been infected with the Zika virus during their pregnancies.
Conceicao Alcantara, a 34- year- old woman who had recently given birth, is on their list. Her daughter had been born with microcephaly, a serious condition that leaves babies with an abnormally small skull and, often, an underdeveloped brain.
Alcantara has been reluctant to speak to the investigators – an American pediatrician, and two nurses and a phlebotomist from Brazil. She doesn’t want her tiny daughter turned into a public curiosity, she says.
As a physiotherapist herself who’d worked with microcephalic babies, Alcantara already knows the condition’s devastating potential impact: seizures, learning disabilities, problems with speech, vision, hearing and motor function, and for some, a shortened life span.
Are these researchers going to accomplish anything?
A local health worker agrees to take the team to Alcantara’s house to see if she might be persuaded. The health worker guides the group’s small Fiat down narrow, cobblestoned streets to a cream- coloured house behind a forbidding metal gate.
Marcia de Andrade, one of the nurses on the team, bangs on the gate while the others stay in the car. The gate opens a crack, and De Andrade disappears inside.
She is gone nearly an hour. Finally, the gate opens again, and De Andrade motions for the rest of the team to come inside.
There is now strong scientific consensus that Zika, which for decades was thought to be relatively harmless and often has no symptoms, can cause microcephaly and other serious neurological damage – thanks in part to the work done by this and other investigative teams.
Brazil had seen an increase in microcephaly cases unparalleled elsewhere in the world; early this year, the US Centers for Disease Control and Prevention ( CDC) dispatched researchers to the country to help unravel the mystery.
For a month, the team in the Fiat and seven others like it fanned out across the north- eastern state of Paraiba, logging thousands of miles on undulating country roads and narrow alleyways.
In May, Brazilian health authorities confirmed 1,434 births since October 2015 with malformations that may be Zika- related and were investigating thousands of others. In June, The New York Times reported that there were 234 pregnant women in the United States with Zika, quoting CDC figures.
Zika is believed to have arrived in Brazil in 2014, most likely brought in by a traveller from the Pacific Islands. The virus has now reached 60 coun- tries and territories, including large swaths of the Americas where there is an abundance of the Aedes aegypti mosquito that spreads the virus – and almost no one has the immunity that has developed in parts of Africa and Asia.
The increase in microcephaly cases in Brazil began in the state of Pernambuco, just south of Paraiba. Genetic disorders, certain viruses and other known causes of microcephaly did not seem to be an issue in these cases.
Something else was going on, and Alcantara’s pregnancy became a key piece of the puzzle.
Her obstetrician had noticed during an ultrasound that the fetus’s head was not developing normally, and then heard of the cases of microcephaly in nearby Pernambuco.
Those cases, doctors were beginning to suspect, might be linked to Zika. Many of the women had experienced a rash typical of the virus early in their pregnancies – did Alcantara remember having a rash? She did. Her doctor found a lab that could test for Zika in her amniotic fluid, and it was positive. The finding was a breakthrough – some of the first biological evidence connecting the virus to microcephaly.
“Never before in history has there been a situation where a bite from a mosquito could result in a devastating malformation,” says Dr Thomas Frieden, the CDC director.
Over the next few months, the evidence favouring a Zika connection mounts. Other countries with outbreaks start reporting cases of microcephaly. Brain tissue collected from still births test positive for the virus, as does spinal fluid from babies with microcephaly.
In Paraiba, the detectives start with a list of more than 800 reported cases of microcephaly in the region, which they winnow to a sample of 190.
They focus on severe cases, based on the head’s circumference at birth – 32cm for boys and 31.5cm for girls – as well as its size relative to body length. Just 3% of newborns have heads that small.
For each mother who agreed to take part, the researchers wanted to enroll, as a control, three others whose babies had been born at around the same time and in the same place but who do not have microcephaly.
Dr Megumi Itoh, the San Francisco pediatrician who is on the team with De Andrade, worries how families will respond to strangers showing up at their homes, asking intimate questions and taking blood samples.
The researchers have a bigger challenge first: finding them. The mothers are spread across nearly 57,000sq km, from the densely populated coast to the hinterlands of the interior.
The teams set out in Paraiba’s state capital, Joao Pessoa, often with little more than a name and a neighbourhood. They go from clinic to clinic searching for more information – “We literally go in and say, ‘ Do you know this mum?’ ” Dr Itoh says. And when the teams locate an address, the mother might not be home.
In the town of Sao Vicente do Serido, an elderly shopkeeper points the researchers towards the municipal health secretariat on a cobblestoned street of houses painted pastel yellow, blue and green.
The town recently had its first case of microcephaly and expectant mothers here are desperate to know if their babies might also be at risk.
“It is so good to have you,” says Constanca Goncalves, a primary care coordinator, as she leads the team into an office.
The researchers sort through reams of paperwork and use a pillow to turn a cabinet into an examination table.
Two mothers are waiting to see them, while another hasn’t shown up yet. All have healthy babies and are there to serve as control cases.
A shy mother in shorts and a tank top enters the room cradling a sleeping baby girl. But there is a problem. The mother, Maria Girdielly, is 17. They need a parent’s consent to enroll the pair in the study.
Goncalves pulls up a number on her cellphone and diales the girl’s mother. She’s busy making lunch for her employer.
“Can you just come sign the paperwork?” Goncalves pleads. “We will come in a car to get you and bring you right back.”
The Fiat is dispatched, and 10 minutes later Maria’s mother, Creusa dos Santos, walks into the room. She looks nervous.
“You have a chance to help a lot of other mothers,” De Andrade says. The woman signs the forms.
In the afternoon, they visit a clinic in Juazeirinho, the town where they would meet Alcantara the next day.
Waiting for them is Sabrina Mateus, her mother and her two- month- old son, who was born with microcephaly.
After measuring the infant’s head, Dr Itoh takes photographs to document its shape and proportions.
De Andrade assures the 17- year- old mother that they will not be shared on social media networks – a worry in a country where curiosity about the condition has meant that its victims are sometimes treated like characters in a national freak show.
The baby screams as another team member draws a sample of his blood, then one from his mother. An antibody test will indicate whether they have been exposed to the virus.
Did she experience any rashes during her pregnancy, De Andrade asks the mother. Any fever? Headaches? Joint pain? Red eyes? She shakes her head no.
Had she had any other infections? Was she exposed to pesticides? Did she drink? No.
De Andrade writes down each answer on a standardised form. The questions continue for half an hour.
Many Brazilians remained doubtful that the surge in microcephaly could be traced to Zika for a long time. Various other theories gained popular currency: expired vaccines, genetically modified mosquitoes released to combat dengue fever, a larvicide used to prevent mosquitoes from breeding in standing water.
Government officials hoped at that time that the CDC’s study would provide a definitive answer. In the end, 600 mothers agreed to participate in the research.
A preliminary analysis was not surprising: Mothers whose babies have microcephaly were more likely than other women to have experienced symptoms during pregnancy that could be caused by Zika. There were no other obvious explanations for the epidemic.
Around the globe, health authorities began to take precautions as word spread.
But the researchers still need to find answers to questions such as why some babies were born healthy while others have forever changed the lives of their families. Dr Itoh understands that the puzzle she began solving is laying new jigsaw pieces around the world. But that only means the disease detectives need to hurry.
“It’s mind- boggling to me that a virus could do this,” she says. – Los Angeles Times/ Tribune News Service
Vital numbers: A notebook belonging to Dr Meg Itoh, an epidemic intelligence officer with the US Centers for Disease Control and prevention, used for tracking patients as part of the CDC and Brazil’s investigation into the connection between women having the Zika virus when they are pregnant and microcephaly in their babies.
After measuring a child’s head dr Itoh ( centre) is showing teenaged mother Sabrina where her baby’s head measurement of 34.2cm falls on a growth chart – well below the 1/ 3 percentile of babies that age.
Vital research: dr Itoh ( left) measuring the head of fivemonth- old Adrielly rufino, as she is held by her mother Maria.
‘ She’s everything in my life. It doesn’t matter what she has, what she has, for me, it’s nothing,’ says Maria da Luz Mendes Santos about her daughter, Heloyse, who was born with microcephaly. ‘ She brought a lot of happiness to my family.’
Six- month- old eloisa de oclaceo is part of the control group of babies without microcephaly.
researchers Marcilia Souza ( left) and Veronica dantas preparing samples for analysis in a lab in Brazil.