Four million could be affected by vicious zika virus
Race on to find vaccine as Brazilian mum tells of struggle to cope with son's devastating birth defect
Published 31/01/2016 | 02:30
Companies and scientists are racing to create a Zika vaccine as concern grows over the mosquito-borne virus that has been linked to severe birth defects and is spreading quickly through the Americas.
Zika is now present in 23 countries and territories in the Americas. Brazil, the hardest-hit country, has reported around 4,000 cases of the devastating birth defect called microcephaly that are strongly suspected to be related to Zika.
The World Health Organisation (WHO), stung by criticism that it reacted too slowly to West Africa's Ebola epidemic, convenes an emergency meeting tomorrow to help determine its response to the spread of the virus.
The US Centers for Disease Control and Prevention has activated an emergency operations centre staffed around the clock to address Zika.
On Thursday, the WHO said as many as four million people in the Americas may become infected by Zika, adding urgency to the research efforts.
Vaccine developers made clear a vaccine for widespread public use is at least months, if not years, away.
The closest prospect may be from a consortium including drugmaker Inovio Pharmaceuticals Inc that could have a vaccine ready for emergency use before year-end, according to one of its lead developers.
Canadian scientist Gary Kobinger said on Thursday the first stage of testing on humans could begin as early as August. If successful, the vaccine might be used during a public health emergency by October or November, said Kobinger, who helped develop a trial vaccine for the Ebola virus.
Zika had been viewed as a relatively mild illness until Brazilian health officials identified it as a matter of concern for pregnant women. While a direct causal relationship has not been established, scientists strongly suspect a link between Zika and thousands of children born in Brazil with abnormally small heads, brain defects and impaired vision.
There is no treatment for Zika infection.
Efforts to combat Zika are focused on protecting people from being bitten and on eradicating mosquitoes, a tough task in many parts of Latin America, where people live in poverty and there are plentiful breeding grounds for the insect.
"We do not have a vaccine for Zika yet. The only thing we can do is fight the mosquito," Brazilian President Dilma Rousseff said on Friday, reiterating her call for a national eradication effort. Rousseff said tests for the development of a vaccine would begin next week at the Butantan Institute, one of Brazil's leading biomedical research centres in Sao Paulo.
US President Barack Obama spoke on Friday with Rousseff about the spread of the virus, the White House said. "The leaders agreed on the importance of collaborative efforts to deepen our knowledge, advance research and accelerate work to develop better vaccines and other technologies to control the virus," the White House said in a statement.
Zika has hit Brazil just as it prepares to host the Olympic Games in Rio de Janeiro in August, an event that draws hundreds of thousands of athletes, team officials and spectators. The International Olympic Committee (IOC) assured teams on Friday the Olympics would be safe from Zika, but urged visitors to carefully protect themselves.
US lawmakers have begun to press the Obama administration for details of its response to Zika. At least 31 people in the country have been infected, all of them after travel to affected countries.
Dr Anthony Fauci, director of the US National Institute of Allergy and Infectious Disease, said he did not expect the United States to be hit hard like other some countries in South America and the Caribbean.
"We prepare for the possibility of a major outbreak but we believe it is unlikely to happen," Fauci said.
Meanwhile in Brazil, one mother shared her struggle to cope after giving birth to a baby with microcephaly - where infants are born with unusually small heads, and can sometimes suffer intellectual disability or a host of health and developmental problems that may be connected to the virus,.
Around the fifth month of her pregnancy, Daniele Ferreira dos Santos fell ill with a high fever and angry red splotches on her skin.
She soon recovered.
But weeks later, when she went to the hospital for a prenatal exam, the news was horrific - the baby she was carrying likely had a severe brain injury. When Juan Pedro Campos dos Santos came into the world in December, the circumference of his head was just 26 centimetres, about 20pc smaller than normal.
Santos was never diagnosed with Zika, but she blames the virus for her son's defect and for the terrible toll it has taken on her life.
Living in Recife in Brazil's northeastern state of Pernambuco, she is at the epicentre of the Zika outbreak, and Juan Pedro is among the thousands of suspected cases of microcephaly in Brazil.
Zika was first registered in Brazil in the middle of last year, spreading like wildfire through the northeast thanks in part to the region's widespread poverty, equatorial heat and chronic infestations of the Aedes aegypti mosquito.
"It's the proverbial perfect storm," said Dr Albert Ko, a professor of epidemiology with the Yale School of Public Health, adding the region was likely at least one of the initial points of entry for the disease - which researchers theorise may have been introduced to Brazil by tourists visiting the country during the 2014 World Cup or an international canoeing event the same year.
Mosquitoes have long been an inescapable part of the lives of the Santos family and their neighbours in a slum in Recife's Apipucos neighbourhood, where raw sewage flows in ditches, rain water from the frequent downpours in this equatorial city accumulates in fetid puddles, and the shores of a nearby pond are dotted with trash.
Each soda bottle, yoghurt container and margarine tub provides an ideal breeding ground for Aedes.
"The mosquito is in all Recife. If I didn't get it here, I got it at the place I work," said Santos, a receptionist. "We all know that the risk [of contracting a mosquito-borne illness] is high."
But it wasn't always this way. Brazil once succeeded in eliminating the Aedes, which is well adapted to humans, lives within people's homes and can breed in just a bottle cap of stagnant water. Massive eradication efforts in the 1940s and 1950s allowed the country to be declared free of the mosquito in 1958, but over the decades the insect returned, slowly encroaching from neighbouring countries and finding fertile breeding ground in Brazil's sprawling, unplanned cities, with their limited potable water systems and garbage collection.
"Because of irregular water distribution, many people, especially in poorer areas, collect water in tanks. . . creating ideal breeding grounds for the mosquitoes," said Dr Ceuci Nunes, an infectologist at a hospital in the city if Salvador. "The same goes with trash, which often goes uncollected."
Nunes added that regional officials' laissez-faire attitude toward eradication also helped fan the mosquito's proliferation, which also resulted in as record numbers of dengue cases in recent years.
"There has been a lot of carelessness combating the [Aedes] mosquito," she said, adding that many municipalities simply "failed to adopt adequate mosquito-fighting measures."
Officials on the ground worry president Dilma Rousseff's declaration to fight the Aedes might be hollow. Recife's health secretary, Jailson Correia, an infectologist, said the city asked the Brazilian government for US$7m for Aedes eradication programmes back in November. The payout only came this month, he said, and it was only US$300,000.
Area researchers are also exploring whether another type of mosquito endemic to Brazil's northeast could also be a Zika carrier, and if so, whether it too may somehow lead to microcephaly. The carrier of West Nile virus, the Culex quinquefasciatus mosquito, is up to 20 times more prevalent in the region than Aedes, which could help explain the intensity of the Zika outbreak there.
If the hypothesis proves true, staunching Zika's spread could prove more difficult than previously thought, said Constancia Ayres, a researcher with the Fiocruz Institute in Recife. "If that's the case, the problem is more complex. Only a proper sanitation system would help," she said. "Culex reproduces in dirty waters, unlike Aedes."
For the moment, the best way to avoid infection remains avoiding mosquito bites - a tall order in Recife, where worry over Zika's effects has sparked widespread runs on mosquito repellents.
And in the few spots where it's still available, frenetic demand has helped push the price for what was already a costly product into the stratosphere. In Recife's airport, a small bottle was running for US$8 - a fortune in a region where the per capita household income is around US$160 per month, according to official statistics.
The Brazilian government is now pledging to hand out repellent to low-income pregnant women, but the gesture is cold comfort to new mother Santos.
Asked whether she had any repellent, she just laughed. She has little reason to laugh these days.
Almost from birth, Juan Pedro cried ceaselessly, as do many babies with microcephaly. He stops only for the few hours when he's asleep. During those precious hours, Santos - whose husband walked out shortly after Juan Pedro's birth - keeps her fingers close to his chest so he has something of her to grab onto.
Without that, he pinches himself awake with his tiny fingers.
What you need to know about the mosquito-borne disease
The virus is transmitted to people through the bite of infected female Aedes mosquitoes, the same type of mosquito that spreads dengue, chikungunya and yellow fever. Efforts to control the spread of the virus include eliminating mosquito breeding sites and taking precautions against mosquito bites such as using insect repellent and mosquito nets.
- People who get Zika virus disease typically have a mild fever, skin rash, conjunctivitis, muscle and joint pain and fatigue, with symptoms normally lasting for two to seven days. Most people never develop symptoms.
- The virus has been linked to a devastating birth defect called microcephaly. The WHO said a direct causal relationship between Zika virus infection and birth defects has not yet been established but is strongly suspected. Given an estimated 80pct of people infected have no symptoms, it can be hard to tell if a pregnant woman has been infected. Research by Brazilian authorities indicates the greatest risk of microcephaly appears to be associated with infection during the first trimester of pregnancy.
- The Pan American Health Organization (PAHO) said Aedes mosquitoes are found in all countries in the Americas except Canada and continental Chile, and the virus will likely reach all countries and territories of the region where Aedes are found.
- Zika virus is found in tropical locales with large mosquito populations. Outbreaks of Zika virus disease have been recorded in Africa, the Americas, Southern Asia and Western Pacific. The virus was first identified in Uganda in 1947 in rhesus monkeys and was first identified in people in 1952 in Uganda and Tanzania, according to the WHO.
- One case of possible person-to-person sexual transmission has been described but PAHO said more evidence is needed to confirm whether sex is a means of transmission. No evidence the virus can be transmitted through breast milk.
- The WHO says that because no big Zika outbreaks were recorded before 2007, little is known about complications caused by infection.