Tag Archives: World Health Organization

Zika mystery deepens with evidence of nerve cell infections

Aedes aegypti mosquitoe

By Julie Steenhuysen

CHICAGO (Reuters) – Top Zika investigators now believe that the birth defect microcephaly and the paralyzing Guillain-Barre syndrome may be just the most obvious maladies caused by the mosquito-borne virus.

Fueling that suspicion are recent discoveries of serious brain and spinal cord infections – including encephalitis, meningitis and myelitis – in people exposed to Zika.

Evidence that Zika’s damage may be more varied and widespread than initially believed adds pressure on affected countries to control mosquitoes and prepare to provide intensive – and, in some cases, lifelong – care to more patients. The newly suspected disorders can cause paralysis and permanent disability – a clinical outlook that adds urgency to vaccine development efforts.

Scientists are of two minds about why these new maladies have come into view. The first is that, as the virus is spreading through such large populations, it is revealing aspects of Zika that went unnoticed in earlier outbreaks in remote and sparsely populated areas. The second is that the newly detected disorders are more evidence that the virus has evolved.

“What we’re seeing are the consequences of this virus turning from the African strain to a pandemic strain,” said Dr. Peter Hotez, dean of the National School of Tropical Medicine at Baylor College of Medicine.

The Zika outbreak was first detected in Brazil last year and is spreading through the Americas. It has been linked to thousands of suspected cases of microcephaly, a typically rare birth defect marked by unusually small head size, signaling a problem with brain development. Evidence linking Zika to microcephaly prompted the World Health Organization to declare a global health emergency in February.

The suspicion that Zika acts directly on nerve cells began with autopsies on aborted and stillborn fetuses showing the virus replicating in brain tissues. In addition to microcephaly, researchers reported finding other abnormalities linked with Zika including fetal deaths, placental insufficiency, fetal growth retardation and injury to the central nervous system.

Doctors also are worried that Zika exposure in utero may have hidden effects, such as behavioral problems or learning disabilities, that are not apparent at birth.

“If you have a virus that is toxic enough to produce microcephaly in someone, you could be sure that it will produce a whole series of conditions that we haven’t even begun to understand,” said Dr. Alberto de la Vega, an obstetrician at San Juan’s University Hospital in Puerto Rico.

First discovered in the Zika forest of Uganda in 1947, the virus circulated quietly in Africa and Asia, causing rare infections and producing mild symptoms. A 2013 outbreak in French Polynesia, the largest at that time, led researchers to make the Guillain-Barre link. Other neurological effects were noted but scientists made little of them at the time.

A rare and poorly understood condition, Guillain-Barre can weaken muscles and cause temporary paralysis, often requiring patients to need respirators to breathe.

An estimated 32,000 people in the French Polynesia Zika outbreak were infected, and 42 patients were confirmed to have Guillain-Barre, a 20-fold increase in incidence over the previous four years, the WHO reported. Another 32 patients had other neurological disorders, including encephalitis, meningoencephalitis, myelitis and facial paralysis.

Guillain-Barre is an autoimmune disorder, in which the body attacks itself in the aftermath of an infection. But the newly discovered brain and spinal cord infections are known to be caused by a different mechanism – a direct attack on nerve cells. That has prompted scientists to consider whether the Zika virus also may infect nerves directly in adults, as they already have suspected in fetuses.

In medical journals published last month, doctors described neurological syndromes in two patients that they attributed to Zika. Doctors in Paris diagnosed meningoencephalitis, an infection of both the brain and spinal cord, in an 81-year-old man who was hospitalized after being exposed to Zika on a cruise.

Another French team reported acute myelitis, a paralyzing infection of the spinal cord, in a 15-year-old girl who had been infected with Zika on the French Caribbean island of Guadeloupe.

In its latest surveillance report, the WHO said the two cases “highlight the need to better understand the range of neurological disorders associated with Zika-virus infection.”

Other mosquito-borne viruses – including dengue, Japanese encephalitis and West Nile – are known to directly infect nerve cells in the brain and spinal cord. But such viruses are seldom associated with Guillain-Barre, and never with microcephaly, said Baylor’s Hotez.

POSSIBLE EVOLUTION

In a recent paper, WHO researcher Mary Kay Kindhauser wrote that Zika “appears to have changed in character,” noting its transition from a mild infection to one causing “large outbreaks linked with neurological disorders.”

Scientists studying Zika in Brazil now are reporting the same neurological disorders seen in French Polynesia. From April through July 2015, doctors in Brazil identified a spike in Guillain-Barre cases.

In Salvador, there were roughly 50 reported cases of Guillain-Barre in July alone, far more than would typically be expected, Dr. Albert Ko, a tropical disease expert from Yale University who is studying Zika in the coastal city of Salvador, recently told a research symposium.

“Throughout Brazil, doctors have seen strange, atypical, neurological manifestations,” Ko said told the symposium.

Zika exposed patients have had other neurological problems as well, including acute disseminated encephalomyelitis, which causes inflammation of the myelin, the protective sheath covering nerve fibers in the brain and spinal cord. Other patients experienced tingling, prickling or burning sensations, which are often markers of peripheral nerve damage.

In addition to Brazil and French Polynesia, at least 11 more countries and territories have reported hundreds of cases of Guillain-Barre syndrome linked to Zika. In Brazil, Guillain-Barre cases jumped 19 percent to 1,708 last year.

El Salvador, a country that has an annual average of 196 cases of Guillain-Barre, reported 118 cases in six weeks in December and January.

Zika’s arrival in Colombia in October 2015 was associated with another increase in Guillain-Barre cases. The country typically reports 242 cases of the syndrome a year, or about five a week. But in the five weeks starting in mid-December, Colombia reported 86 cases of Guillain-Barre, or about 17 a week.

Dr. Carlos Pardo-Villamizar, a neurologist at Johns Hopkins University School of Medicine, is studying Zika complications with colleagues in five Colombian research centers. They have seen cases of encephalitis, myelitis and facial paralysis associated with Zika and want to understand what is triggering these complications.

They also want to study whether prior infection with dengue or chikungunya – two related viruses – are contributing to neurological disorders seen in patients with Zika.

Scientists are turning their attention next to Puerto Rico, where Zika is expected to infect hundreds of thousands of residents by year-end.

More cases hold the potential for “a better sense of the full spectrum of disease that Zika is capable of causing,” said Dr. Amesh Adalja of the Center for Health Security at the University of Pittsburgh Medical Center.

(Reporting by Julie Steenhuysen; additional reporting by Anthony Boadle in Brasilia, Brazil; Editing by Michele Gershberg and Lisa Girion)

WHO backs new weapons in fight against Zika virus

LONDON (Reuters) – Countries battling the Zika virus should consider new ways to curb disease-carrying mosquitoes, including testing the release of genetically modified insects and bacteria that stop their eggs hatching, the World Health Organization said on Tuesday.

“Given the magnitude of the Zika crisis, WHO encourages affected countries and their partners to boost the use of both old and new approaches to mosquito control as the most immediate line of defence,” it said.

The WHO also highlighted the potential of releasing sterile irradiated male mosquitoes, a technique that has been developed at the United Nations’ International Atomic Energy Agency (IAEA).

Zika, which is now sweeping the Americas, is transmitted primarily by the Aedes aegypti mosquito, which the U.N. health body described as an “opportunistic and tenacious menace”.

Many scientists believe Zika could be linked to microcephaly, or abnormally small heads, in newborns and a serious neurological disorder in adults called Guillain-Barre syndrome.

“If these presumed associations are confirmed, the human and social consequences for the over 30 countries with recently detected Zika outbreaks will be staggering,” the WHO said.

Fighting the infection at source by eliminating the Aedes aegypti mosquitoes responsible for transmission is moving up the public health agenda, especially as the same insects also spread dengue, chikungunya and yellow fever.

However, the concept of wiping out an entire mosquito species also raises serious ecological questions, since it runs counter to preserving biodiversity.

Still, insect control expert Jo Lines at the London School of Hygiene and Tropical Medicine has few qualms. “This is an invasive species, so getting rid of these mosquitoes would, if anything, restore the natural ecology, not destroy it,” he told Reuters.

Like rats and pigeons, Lines argues, Aedes aegypti has adapted perfectly to modern urban living by breeding in everything from discarded bottle tops and used car tyres to pet water bowls and vases in cemeteries.

As a result, the diseases it carries are likely to be a growing threat to humankind in the years ahead.

BEYOND SPRAYING

While spraying or “fogging” with insecticide can provide part of the solution, WHO experts said they recommended evaluating newer tools, including a genetically modified prototype mosquito developed by Oxitec, the British subsidiary of Intrexon.

The male mosquitoes are modified so their offspring will die before reaching adulthood and being able to reproduce.

The WHO said its Vector Control Advisory Group recommended further field trials of the technique, following promising previous tests in the Cayman Islands.

Another option involves the mass release of male insects that have been sterilised by low doses of radiation, which the IAEA has already used to control tsetse fly in parts of Africa.

An alternative approach uses Wolbachia bacteria, which do not infect humans but cause the eggs of females that mate with infected males to fail to hatch. Mosquitoes carrying Wolbachia have been shown to reduce mosquitoes’ ability to transmit dengue.

The WHO said large-scale field trials of Wolbachia bacteria would be started soon.

Much remains unknown about Zika, including whether the virus actually causes microcephaly. The WHO believes the suspected link could be confirmed within weeks.

Brazil is investigating more than 4,300 suspected cases of microcephaly. Researchers have confirmed more than 460 of these cases as microcephaly and identified evidence of Zika infection in 41 of them.

There is no specific treatment for a Zika and it will be at least 18 months before any vaccines are tested in large-scale clinical trials, the WHO estimates.

(Additional reporting by Tom Miles; Editing by Alison Williams)

Zika virus outbreak may not change abortion in Brazil

RECIFE (Reuters) – Six months pregnant with her first child, Eritania Maria has a rash and a mild fever, symptoms of the Zika virus linked to brain deformities in newborn children in Brazil.

But the 17-year-old is too scared to take a test to confirm if she has Zika.

Like other women in the slums of Recife, which squat on stilts over mosquito-ridden marshland in northeast Brazil, Maria has few options if her child develops microcephaly, the condition marked by an abnormally small head and underdeveloped brain that has been linked to Zika.

Brazil has amongst the toughest abortion laws in the world and is culturally conservative. Even if she wanted an illegal abortion and could afford one, Maria is too heavily pregnant for a doctor to risk it. So she prefers not to know.

“I’m too scared of finding out my baby will be sick,” she told Reuters, her belly poking out from beneath a yellow top.

The Zika outbreak has revived the debate about easing abortion laws but Maria’s case highlights a gap between campaigners and U.N. officials calling for change and Brazil’s poor, who are worst affected by the mosquito-borne virus yet tend to be anti-abortion.

Add a conservative Congress packed with Evangelical Christians staunchly opposed to easing restrictions, plus the difficulty of identifying microcephaly early enough to safely abort, and hopes for change seem likely to be frustrated.

As with many countries in mostly Roman Catholic Latin America, Brazil has outlawed abortion except in cases of rape, when the mother’s life is at risk or the child is too sick to survive.

An estimated 850,000 women in Brazil have illegal abortions every year, many under dangerous conditions. They can face up to 3 years in prison although in practice, jail terms are extremely rare.

With two-thirds of the population Catholic and support for Evangelicals growing fast, polls show Brazilians oppose changing the law. A survey by pollster VoxPopuli in 2010 showed that 82 percent reject decriminalization, while a Datafolha poll the same year put the figure at 72 percent.

Vandson Holanda, head of health for the Catholic Church in Brazil’s northeast, said there was no chance the Church would shift its position on abortion because of Zika.

Suspected cases of microcephaly have topped more than 4,000 – with more than 400 of those confirmed so far – since Zika was first detected in April. Around one-third of the suspected cases are in Pernambuco state around Recife.

The figures, which compare with around 150 cases across Brazil in a normal year, show no signs of slowing.

While there is no scientific proof of a connection between Zika and microcephaly, the World Health Organization (WHO) declared the outbreak a global emergency this month, citing a “strongly suspected” link. The virus has spread to 26 countries in the Americas since arriving in Brazil.

Women’s rights groups in Brazil such as Anis plan to appeal to the Supreme Court to relax Brazil’s abortion laws. They hope to build on a successful case in 2012 that legalized abortion for anencephaly, where the fetus develops without a major part of its brain and skull.

Given the difficulty of identifying microcephaly before the final weeks of pregnancy, Sinara Gumieri, a legal advisor to Anis, said the group would petition the court to legalize abortion for women diagnosed with Zika whose child was at risk of the condition, even if it is not diagnosed in the fetus. She admitted it would be difficult.

The doctors who led the anencephaly campaign in 2012 do not expect its success to be repeated.

“It’s completely different,” said Eugenio Pita, a doctor in Recife who performed legal abortions through the public health system for 20 years. “With anencephaly, the baby does not live; an abortion is only speeding up the inevitable. Babies born with microcephaly usually survive.”

CONSERVATIVE CONGRESS TIGHTENING LAW

Legislative reforms seem even more unlikely. A 2014 election returned a more conservative Congress, packed with Evangelicals, who account for roughly a fifth of Brazil’s 200 million people.

The speaker of the lower house, Eduardo Cunha, elected with the backing of Evangelical congressmen, has proposed legislation to make it harder to get an abortion in cases of alleged rape, sparking protests across Brazil last year.

Hundreds of Brazilian women die or are seriously injured each year in botched illegal abortions involving improvised equipment — mostly women not wealthy enough to travel abroad or pay for a proper doctor.

“Illegal abortions bring with them serious risks, the complications of which we have to pay careful attention to,” said Jailson Correia, Recife’s health secretary, calling for a national debate on liberalizing the law.

So far, there is inconclusive evidence that Zika has led to a rise in abortions. The website Women on Web, an Amsterdam-based charity that has offered to send free abortion pills to pregnant women infected with Zika, said email requests from Brazil asking about the service tripled last week.

The pills can be used to terminate pregnancy in the first 12 weeks.

But a for-profit online service, Aborto na Nuvem, said it reported no change beyond a usual 15-20 percent monthly increase the site has registered since it launched last year. Its co-founder, Heinrick Per, said the service was mainly used by wealthy Brazilians and he did not expect to see a rise because of Zika.

DETECTED LATE

With state-of-the-art equipment, experts say signs of microcephaly may be detected from about 24 weeks but it is impossible to determine how severe a case it might be. In Brazil, if identified before birth at all, it is usually registered at 30 to 32 weeks, by which time most doctors will not perform an illegal abortion.

“After 12 weeks it is hard to find a doctor to do an illegal abortion in Brazil. After 24 weeks, it’s impossible,” said Dr Elias Melo, a leading obstetrician at Hospital das Clinicas in Recife.

Though they are rarely prosecuted, doctors can face up to 10 years in prison.

“It’s not just a legal thing, it is cultural as well,” Melo said, noting that by 30 to 32 weeks you have a 2 kilogram (4.4 lb) baby that could survive if removed from the womb.

Complicating matters, as many as 80 percent of people with Zika do not show symptoms and there is no quick and reliable test for the virus widely available.

As a result, some women may opt for preemptive abortions early in pregnancy to avoid the risk of microcephaly, experts say.

French historian of science Ilana Löwy draws parallels with rubella in Britain and France in the 1950s, when abortion was illegal yet the number of terminated pregnancies rose dramatically.

Yet unlike with rubella, where up to 85 percent of fetuses infected in early pregnancy develop defects, doctors so far have no proof that Zika causes microcephaly, let alone an idea of its likelihood.

“Half of my 50 patients had Zika-like symptoms at some stage of their pregnancy,” said Melo. “Not one of them had a child born with microcephaly.”

Still, a dramatic rise in microcephaly cases could put a huge burden on poor families and public health services already under strain.

At a hospital in Recife, Gabriela Falcao cradles her 2 month old baby who was born with microcephaly and twisted legs as she waits to see a doctor.

“If I could go back, I still wouldn’t have an abortion,” she said. “I hold out hope my baby will grow to be like other kids.”

(Additional reporting by Ueslei Marcelino; Editing by Daniel Flynn and Kieran Murray)

Hawaii County declares state of emergency over dengue fever outbreak

The growing number of dengue fever cases in Hawaii County has prompted the county’s mayor to declare a state of emergency, a measure that aims to reduce the spread of the disease.

William P. Kenoi issued the declaration on Monday as the state Department of Health reported that there have been confirmed 251 cases of the mosquito-borne illness since last September.

All of the confirmed cases have been in Hawaii County, which is the state’s largest island.

Kenoi’s declaration allows people to dump tires at county landfills, which had been outlawed. The Centers for Disease Control and Prevention (CDC) says used tires can collect rain, making them a good place for mosquitos to lay eggs, and mosquito control is key to combating dengue.

Hawaii Governor David Y. Ige issued a statement saying he supported Kenoi’s emergency proclamation, but he would only declare a statewide emergency if certain conditions were met.

According to the World Health Organization (WHO), dengue fever usually triggers a flu-like illness that lasts up to a week. Symptoms include headaches, vomiting, muscle pains and rashes. In some cases, however, dengue can become severe and lead to potentially fatal complications.

The WHO says severe dengue causes about 500,000 hospitalizations and 12,500 deaths every year, though access to proper medical care significantly lowers the disease’s mortality rate.

Hawaii health officials have not reported any deaths as a result of this outbreak.

The Hawaii Department of Health says dengue isn’t usually found in Hawaii, but there have been some cases of infected travelers coming to Hawaii from areas where the disease is spread. But it says this outbreak is of locally-acquired dengue, the state’s first such event since 2011.

Dengue is different than the Zika virus, another mosquito-borne illness. However, both dengue and Zika can be transmitted by the Aedes aegypti mosquito and both have spread to new areas.

The WHO says dengue has reached more than 100 countries over the past 50 years, recording a 30-fold increase in its incidence. About half the world’s population is now at risk of infection.

The CDC has issued numerous travel warnings about the Zika virus, and the WHO recently deemed Zika an international public health concern as scientists investigate its potential connection to a rare birth defect called microcephaly that affects head size.

The Hawaii Department of Health has said that one Oahu child who was born with microcephaly had been infected with Zika, though his mother likely got infected when she was living in Brazil. The country saw a substantial rise in microcephaly last year.

Only about 20 percent of those infected with Zika show any symptoms, according to the CDC. Those symptoms include fever, rash and joint pain and most people fully recover within a week.

First U.S. Zika virus transmission reported, sexual transmission cited

AUSTIN, Texas (Reuters) – The first known case of Zika virus transmission in the United States was reported in Texas on Tuesday by local health officials, who said it was contracted through sexual contact and not the bite of a mosquito, a day after the World Health Organization declared an international public health emergency.

Dallas County Health and Human Services said it received confirmation of the case in Dallas from the U.S. Centers for Disease Control and Prevention.

A Dallas County health official said in a tweet that the case was transmitted through sexual contact with someone who had traveled to Venezuela. The person infected did not travel to the South American country, county health officials said.

County authorities said there were no reports of the virus being locally transmitted by mosquitoes in the Texas county.

A CDC spokesman confirmed the results of a test for Zika infection but said local officials investigated the mode of transmission.

Previously, international health officials had noted one case of possible person-to-person sexual transmission. But the Pan American Health Organization said more evidence was needed to confirm sexual contact as a means of Zika transmission.

The WHO has said the virus, linked to severe birth defects in Brazil, has been spreading rapidly in the Americas and could infect 4 million people. It said it had launched a global response unit to fight the mosquito-borne virus, which is spreading rapidly in Latin America. Africa and Asia are also seen as being vulnerable.

The virus has been linked to microcephaly, in which babies have abnormally small heads and improperly developed brains.

“Most important, we need to set up surveillance sites in low- and middle-income countries so that we can detect any change in the reporting patterns of microcephaly at an early stage,” Dr. Anthony Costello said in Geneva. Costello is WHO’s director for maternal, child and adolescent health.

Twenty to 30 sites could be established worldwide, mainly in poor countries without robust healthcare systems.

Brazil, the country hardest hit by Zika, has reported 3,700 suspected cases of microcephaly that may be linked to Zika.

In an address to a joint session of Brazil’s Congress, President Dilma Rousseff said her government will spare no resources in mobilizing to combat the mosquito that transmits the virus. With no vaccine or treatment for Zika, efforts to curb its spread have focused on eradicating mosquito breeding sites.

“There will be no lack of funding,” Rousseff said.

Brazil, which has 3,700 suspected cases of microcephaly that may be linked to Zika, is scheduled to host the Olympics in Rio de Janeiro in August.

Rousseff also said Brazil and the United States will enter a partnership to develop a Zika vaccine as soon as possible to stem the spread of the virus.

The Pan American Health Organization said Zika was now spreading in 26 countries and territories in the Americas.

The virus was first identified in 1947 in rhesus monkeys in Uganda while scientists were studying yellow fever, according to the WHO. It was identified in humans in 1952. Zika is spread by mosquitoes of the Aedes genus.

Sanofi on Tuesday announced that it has lauched a project to develop a vaccine against the virus, the most decisive commitment yet by a major vaccine maker. The company said its Sanofi Pasteur vaccines division would use its expertise in developing vaccines for similar viruses such as yellow fever, Japanese encephalitis and dengue.

The WHO called for urgent development of better tests to detect the virus in pregnant women and newborn babies.

“The reason it’s a global concern,” Costello said of Zika, “is that we are worried that this could also spread back to other areas of the world where the population may not be immune.”

Costello said the Aedes mosquitoes that carry the Zika virus “are present … through Africa, parts of southern Europe and many parts of Asia, particularly South Asia.” Africa and Asia have the world’s highest birth rates.

‘GUILTY UNTIL PROVEN INNOCENT’

WHO Director-General Margaret Chan said on Monday it was “strongly suspected but not yet scientifically proven” that Zika causes microcephaly.

“We believe the association is ‘guilty until proven innocent,'” Costello said, referring to whether Zika causes microcephaly.

A new method to render male mosquitoes infertile by nuclear radiation could help reduce populations of the insect carrying the virus, the Vienna-based U.N. International Atomic Energy Agency U.N. atomic agency said.

Small biotech companies and academic institutions also have plans to develop a Zika vaccine, and GlaxoSmithKline PLC has said it is concluding feasibility studies to see if its vaccine technology was suitable. And on Tuesday other companies joined the effort.

The University of South Australia said it was working on a Zika vaccine with Australian biotech Sementis Ltd.

U.S. drug developer NewLink Genetics Corp said it has started a project to develop Zika treatment options.

Experts have said a Zika vaccine for widespread use is months if not years away.

A Zika case has been identified on mainland Chile for the first time in a man who had traveled to Colombia, where the virus is circulating, local media reported.

An Australian state health service said two Australians were diagnosed with the virus after returning from the Caribbean, confirming the first cases of the virus in the country this year.

(Additional reporting by Dominique Vidalon in Paris, Stephanie Nebehay in Geneva, Shadia Nasralla in Vienna, Ben Hirschler in London, Anthony Boadle in Brasilia, Jane Wardell in Sydney, Amy Sawitta Lefevre in Bangkok, Pedro Fonseca in Rio, Rosalba O’Brien in Santiago, Ankur Banerjee and Amrutha Penumudi in Bengaluru; Writing by Will Dunham; Editing by Toni Reinhold and Jonathan Oatis)

Zika virus linked to birth defects is international emergency, WHO says

GENEVA/LONDON (Reuters) – The World Health Organization has declared the mosquito-borne Zika virus to be an international public health emergency due to its link to thousands of suspected cases of birth defects in Brazil.

WHO Director-General Margaret Chan told reporters on Monday coordinated international action was needed to improve detection and speed work on a vaccine and better diagnostics for the disease, although curbs on travel or trade were not necessary.

The emergency designation was recommended by a committee of independent experts to the U.N. agency following criticism of a hesitant response so far. The move should help fast-track international action and research priorities.

“Members of the committee agreed that the situation meets the conditions for a public health emergency of international concern. I have accepted this advice,” Chan told a news briefing at WHO headquarters.

The WHO said last week the Zika virus was “spreading explosively” and could infect as many as 4 million people in the Americas. Brazil is due to host the Olympic Games in Rio de Janeiro in August.

The WHO was lambasted for reacting too slowly to the Ebola epidemic in West Africa which killed more than 10,000 people in the past two years, and has promised to do better in future global health crises.

U.S. Centers for Disease Control and Prevention head Thomas Frieden said the declaration “calls the world to action” on Zika, while Jeremy Farrar, director of the Wellcome Trust medical charity, said the WHO “should be congratulated for being far more proactive this time”.

Derek Gatherer, a lecturer at Lancaster University, said the WHO’s move was “like a declaration of war … on Zika virus”.

UNDERDEVELOPED BRAINS

Brazil has reported some 3,700 suspected cases of microcephaly, in which infants are born with smaller-than-usual brains. The Health Ministry has linked the condition to Zika, although the connection is not yet definitive.

Chan said the causal link was “strongly suspected but not yet scientifically proven”.

Brazilian Health Minister Marcelo Castro told Reuters on Monday the epidemic was worse than believed because in 80 percent of cases the infected people had no symptoms.

As the virus spreads from Brazil, other countries in the Americas are also likely to see cases of babies with Zika-linked birth defects, experts believe.

The Pan American Health Organization says that Zika has now spread in 24 nations and territories in the Americas. In addition, the Zika virus infection was also reported late last year in Cape Verde.

The Zika virus has raised questions worldwide about whether pregnant women should avoid infected countries.

Chan said delaying travel was something pregnant women “can consider”, adding that if they needed to travel they should take protective measures by covering up and using mosquito repellent.

The clinical symptoms of Zika are usually mild and often similar to dengue, a fever which is transmitted by the same mosquito, leading to fears that Zika will spread into all parts of the world where dengue is commonplace.

More than a third of the world’s population lives in areas at risk of dengue infection, in a band stretching through Africa, India, Southeast Asia and Latin America.

Zika’s rapid spread in Latin America is put down to the prevalence of Aedes aegypti and a lack of immunity among the population.

White House spokesman Josh Earnest said one way for the United States to reduce the risk of Zika there would be to try to control the mosquitoes that carry it.

“At some point here … we’re going to see the temperatures rise (and) that will make for a more hospitable environment for mosquitoes,” he said. “We want to make sure that we have got a strategy to try to limit the spread of this disease when that happens.”

Georgetown University public health and law expert Lawrence Gostin, who last week called on the WHO to act urgently against Zika, welcomed Chan’s declaration but called for a proper strategy, adding: “Actions speak louder than words.”

“Without a clear strategy and ample resources, sounding an alert is simply not enough,” he said.

(Additional reporting by Kate Kelland in London, Roberta Rampton in Washington and Julie Steenhuysen in Chicago.; Editing by Alison Williams)

Race for Zika vaccine gathers momentum as virus spreads

(Reuters) – 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 3,700 cases of the devastating birth defect called microcephaly that are strongly suspected to be related to Zika.

The Geneva-based World Health Organization (WHO), stung by criticism that it reacted too slowly to West Africa’s Ebola epidemic, is convening an emergency meeting on Monday to help determine its response to the spread of the virus.

The U.S. Centers for Disease Control and Prevention has activated an emergency operations center staffed around the clock to address Zika, agency officials told Reuters.

On Thursday, the WHO forecast that as many as 4 million people in the Americas may become infected by Zika, lending new urgency to research efforts already under way. Vaccine developers made clear that 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. Inovio’s share price jumped as much as 13 percent on Friday.

Canadian scientist Gary Kobinger told Reuters 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.

Privately owned vaccine developer Hawaii Biotech Inc said it began a formal program to test a Zika vaccine last fall as the virus started to gain traction in Brazil, although it has no timetable yet for clinical trials.

“Right now, we are in the pre-clinical stage, as I suspect everyone is,” Chief Executive Dr. Elliot Parks told Reuters.

Another private vaccine developer, Boston-based Replikins Ltd, said it was preparing to start animal studies on a Zika vaccine in the next 10 days. Data from the trials on mice and rabbits would likely be out in the next couple of months, Replikins Chairman Samuel Bogoch told Reuters.

“No one has the $500 million on hand to take it (a vaccine) all the way to human trials. Somewhere along the course we hope to have big pockets join us,” Bogoch said.

‘FIGHT THE MOSQUITO’

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. About 80 percent of those infected experience no symptoms, making it difficult for pregnant women to know whether they have been infected.

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 centers in Sao Paulo.

Zika has hit Brazil just as it prepares to host the Olympic Games in Rio de Janeiro on Aug. 5-21, 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.

U.S. 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.

“We need to ensure that federal agencies are working closely together and with the international community to stop its rapid spread,” said Republican Ron Johnson, chairman of the U.S. Senate Homeland Security and Governmental Affairs Committee.

The United States has two potential vaccine candidates and may begin human clinical trials by the end of 2016, U.S. officials said, but there will not be a widely available vaccine for several years.

(Reporting by Natalie Grover and Amrutha Penumudi in Bengaluru; Additional reporting by Julie Steenhuysen in Chicago, Karolos Grohmann in Berlin, Anthony Boadle in Brasilia, Jeffrey Dastin in New York; Writing by Frances Kerry; Editing by Will Dunham)

WHO says Zika ‘spreading explosively,’ 4 million cases a possibility

GENEVA (Reuters) – The Zika virus, linked to severe birth defects in thousands of babies in Brazil, is “spreading explosively” and could infect as many as 4 million people in the Americas, the World Health Organization (WHO) said on Thursday.

Director-General Margaret Chan told members of the U.N. health agency’s executive board the spread of the mosquito-borne disease had gone from a mild threat to one of alarming proportions. The WHO would convene an emergency meeting on Monday to help determine its response, she said.

“The level of alarm is extremely high,” Chan told the Geneva gathering.

“Last year, the virus was detected in the Americas, where it is now spreading explosively. As of today, cases have been reported in 23 countries and territories in the region,” Chan said, promising quick action from the WHO.

The agency was criticized last year for reacting too slowly to West Africa’s Ebola epidemic, which killed more than 10,000 people, and it promised to cut its response time.

“We are not going to wait for the science to tell us there is a link (with birth defects). We need to take actions now,” Chan said, referring to the condition called microcephaly in which babies are born with abnormally small heads and brains that have not developed properly.

There is no vaccine or treatment for Zika, which is like dengue and causes mild fever, rash and red eyes. An estimated 80 percent of people infected have no symptoms. Much of the effort against the illness focuses on protecting people from mosquitoes and reducing mosquito populations.

Developing a safe and effective vaccine could take a year, WHO Assistant Director Bruce Aylward said, and it would take six to nine months just to confirm whether Zika is the actual cause of the birth defects, or if the two are just associated.

“In the area of vaccines, I do know that there has been some work done by some groups looking at the feasibility of a Zika virus vaccine. Now something like that, as people know, is going to be a 12-month-plus time frame,” he said.

U.S. health officials said the United States has two potential candidates for a Zika vaccine and may begin human clinical trials by the end of this year, but there will not be a widely available vaccine for several years.

Marcos Espinal, head of communicable diseases at the Pan American Health Organization, the WHO’s Americas arm, forecast 3 to 4 million Zika cases in the Americas.

As the virus spreads from Brazil, other countries in the Americas are likely to see cases of babies with Zika-linked birth defects, according to Carissa Etienne, regional director for the Pan American Health Organization.

Brazil has reported around 4,000 suspected cases of microcephaly, vastly more than in an average year and equivalent to 1 to 2 percent of all newborns in the state of Pernambuco, one of the worst-hit areas.

The WHO’s Chan said that while a direct causal relationship between Zika virus infection and birth malformations has not yet been established, it is strongly suspected.

“The possible links, only recently suspected, have rapidly changed the risk profile of Zika from a mild threat to one of alarming proportions,” she said.

Health and law expert Lawrence Gostin of Georgetown University in Washington, who had urged the WHO to act, welcomed Chan’s decision to convene an expert meeting, calling it “a critical first step in recognizing the seriousness of an emerging epidemic.”

OLYMPICS CONCERNS

With Rio de Janeiro set to host the Olympics from Aug. 5 to Aug. 21, International Olympic Committee President Thomas Bach said the IOC will issue guidelines this week concerning Zika.

“We will do everything to ensure the health of the athletes and all the visitors,” Bach told reporters in Athens.

Dr. Anne Schuchat of the U.S. Centers for Disease Control and Prevention, said there have been 31 cases of Zika infection among U.S. citizens who traveled to areas affected by the virus.

“It’s possible and even likely that we will see limited outbreaks in the United States,” Schuchat said.

In Washington, U.S. Senator Edward Markey of Massachusetts called on the WHO and the U.S. Department of Health and Human Services to explain how they were tackling the virus because many Americans visit the affected region and more are expected to attend the Olympics.

White House spokesman Josh Earnest said President Barack Obama’s administration’s concern was focused mostly on pregnant women or women who could become pregnant, given the link to microcephaly.

Lufthansa, British Airways and JetBlue became the latest international carriers to offer rebookings or refunds for tickets to areas impacted by the virus.

Lufthansa and British Airways said they would offer pregnant women the opportunity to change their reservations to another destination or delay travel. They stopped short of offering complete refunds as several U.S. airlines have.

(Additional reporting by Kate Kelland in London; Additional reporting by Susan Heavey in Washington and Julie Steenhuysen in Chicago; Writing by Kate Kelland and Will Dunham; Editing by Mark Heinrich and Frances Kerry)

Zika reported in travelers who returned to California, Arkansas and Virginia

Travelers who recently returned to California, Arkansas and Virginia from foreign countries have tested positive for the Zika virus, health officials in those states announced Tuesday.

The Centers for Disease Control and Prevention (CDC) maintains that there haven’t been any people who have contracted the mosquito-borne virus in the United States, though there have been several cases where travelers got infected overseas and brought the virus back with them.

Zika is collecting the attention of public health officials because scientists are studying a possible link between the virus and a rare condition called microcephaly, in which children are born with smaller-than-usual heads. The birth defect can also be caused by other factors, the CDC says.

Still, the CDC has issued travel notices for 22 countries or territories where Zika is currently being spread, urging pregnant women to consider postponing any planned travel to those areas and asking all would-be travelers to “practice enhanced precautions” to prevent mosquito bites.

The three cases announced Tuesday all involved foreign travel.

In a statement, the Virginia Department of Health said the infection was confirmed in “an adult resident of Virginia who recently traveled to a country where Zika virus transmission is ongoing,” but did not elaborate. The infected individual was the state’s first imported Zika case, but isn’t at risk of transmitting the virus because it isn’t currently mosquito season in Virginia.

The Arkansas Department of Health said one of the state’s residents “recently traveled out of the country and had a mild case of Zika.” Officials confirmed the diagnosis late Monday afternoon.

“Arkansas has the kind of mosquitoes that carry Zika virus, so mosquitoes here in Arkansas can become infected with the virus if they bite someone who has Zika,” Dr. Nate Smith, the Arkansas Department of Health Director and State Health Officer, said in a statement. “For this reason, people traveling to countries with Zika should avoid mosquito bites for 10 days after they return.”

The Los Angeles County Department of Public Health said an adolescent girl who traveled to El Salvador last November was the county’s lone confirmed case of Zika, but she has recovered.

“At this time, local transmission is unlikely,” the department said in a statement. “It would require an Aedes mosquito biting a Zika infected person and then biting others.”

The CDC says only about 20 percent of people who are infected with Zika become ill and develop symptoms like fever, rash and joint pain. Most people fully recover from the illness in a week.

The possible link between Zika and microcephaly is a key component of the travel warnings.

The Brazilian Ministry of Health has investigated more than 4,100 microcephaly cases in the past 13 months, according to data released Wednesday. The ministry used to see fewer than 200 cases of the condition every year, though the numbers have surged since Zika arrived in May.

The Hawaii Department of Health has said a child who was recently born with microcephaly there had been infected with Zika, and his mother likely got the virus when she lived in Brazil.

The CDC says it will also be conducting a study to examine a possible link between Zika and Guillain-Barre Syndrome, a nerve disorder than can lead to muscle weakness and paralysis. Many fully recover from the syndrome, the CDC says, though it can be fatal in rare instances.

The World Health Organization is holding an information session on Zika tomorrow.

The organization says it’s possible the virus could cause epidemics in new areas it reaches because people don’t have immunity to it. There’s also currently no vaccine to prevent it.

WHO warns Zika to spread across Americas, spurring vaccine hunt

GENEVA/LONDON (Reuters) – The mosquito-borne Zika virus, which has been linked to brain damage in thousands of babies in Brazil, is likely to spread to all countries in the Americas except for Canada and Chile, the World Health Organization said on Monday.

Zika has not yet been reported in the continental United States, although a woman who fell ill with the virus in Brazil later gave birth to a brain-damaged baby in Hawaii.

Brazil’s Health Ministry said in November that Zika was linked to a fetal deformation known as microcephaly, in which infants are born with smaller-than-usual brains.

Brazil has reported 3,893 suspected cases of microcephaly, the WHO said last Friday, over 30 times more than in any year since 2010 and equivalent to 1-2 percent of all newborns in the state of Pernambuco, one of the worst-hit areas.

The Zika outbreak comes hard on the heels of the Ebola epidemic in West Africa, demonstrating once again how little-understood diseases can rapidly emerge as global threats.

“We’ve got no drugs and we’ve got no vaccines. It’s a case of deja vu because that’s exactly what we were saying with Ebola,” Trudie Lang, a professor of global health at the University of Oxford, said on Monday. “It’s really important to develop a vaccine as quickly as possible.”

Large drugmakers’ investment in tropical disease vaccines with uncertain commercial prospects has so far been patchy, prompting health experts to call for a new system of incentives following the Ebola experience.

“We need to have some kind of a plan that makes (companies) feel there is a sustainable solution and not just a one-shot deal over and over again,” Francis Collins, director of the U.S. National Institutes of Health, said last week.

The Sao Paulo-based Butantan Institute is currently leading the research charge on Zika and said last week it planned to develop a vaccine “in record time”, although its director warned this was still likely to take three to five years.

RIO CONCERNS

The virus was first found in a monkey in the Zika forest near Lake Victoria, Uganda, in 1947, and has historically occurred in parts of Africa, Southeast Asia and the Pacific Islands. But there is little scientific data on it and it is unclear why it might be causing microcephaly in Brazil.

Laura Rodrigues of the London School of Hygiene and Tropical Medicine said it was possible the disease could be evolving.

If the epidemic was still going on in August, when Brazil is due to host the Olympic Games in Rio de Janeiro, then pregnant women should either stay away or be obsessive about covering up against mosquito bites, she said.

The WHO advised pregnant women planning to travel to areas where Zika is circulating to consult a healthcare provider before traveling and on return.

The clinical symptoms of Zika are usually mild and often similar to dengue, a fever which is transmitted by the same Aedes aegypti mosquito, leading to fears that Zika will spread into all parts of the world where dengue is commonplace.

More than one-third of the world’s population lives in areas at risk of dengue infection, in a band stretching through Africa, India, Southeast Asia and Latin America.

Zika’s rapid spread, to 21 countries and territories in the Americas since May 2015, is due to the prevalence of Aedes aegypti and a lack of immunity among the population, the WHO said in a statement.

RISK TO GIRLS

Like rubella, which also causes mild symptoms but can lead to birth defects, health experts believe a vaccine is needed to protect girls before they reach child-bearing age.

Evidence about other transmission routes, apart from mosquito bites, is limited.

“Zika has been isolated in human semen, and one case of possible person-to-person sexual transmission has been described. However, more evidence is needed to confirm whether sexual contact is a means of Zika transmission,” the WHO said.

While a causal link between Zika and microcephaly has not yet been definitively proven, WHO Director-General Margaret Chan said the circumstantial evidence was “suggestive and extremely worrisome”.

In addition to finding a vaccine and potential drugs to fight Zika, some scientists are also planning to take the fight to the mosquitoes that carry the disease.

Oxitec, the UK subsidiary of U.S. synthetic biology company Intrexon, hopes to deploy a self-limiting genetically modified strain of insects to compete with normal Aedes aegypti.

Oxitec says its proprietary OX513A mosquito succeeded in reducing wild larvae of the Aedes mosquito by 82 percent in an area of Brazil where 25 million of the transgenic insects were released between April and November. Authorities reported a big drop in dengue cases in the area.

(Editing by Mark Trevelyan)