Asia outbreaks prompt question: Is all Zika dangerous?

A worker sprays insecticide for mosquitos at a village in Bangkok, Thailand,

By Julie Steenhuysen and Amy Sawitta Lefevre

CHICAGO/BANGKOK(Reuters) – Zika’s rampage last year in Brazil caused an explosion of infections and inflicted a crippling neurological defect on thousands of babies – an effect never seen in a mosquito-borne virus.

It also presented a mystery: why had a virus that had been little more than a footnote in the annals of infectious diseases taken such a devastating turn in the Americas? How had Africa and Asia, where Zika had quietly circulated for decades, escaped with no reports of major outbreaks or serious complications?

Scientists initially theorized that Zika’s long tenure in Africa and Asia may have conferred widespread immunity. Or, perhaps older strains were less virulent than the one linked in Brazil to more than 2,100 cases of microcephaly, a birth defect characterized by arrested brain development.

Now, amid outbreaks in Singapore, Thailand, Vietnam and other parts of Southeast Asia, a much graver explanation is taking shape: perhaps the menace has been there all along but neurological complications simply escaped official notice.

The question is driving several research teams, according to leading infectious disease experts and public health officials.

The answer is immediately important for Asia, the region most affected by Zika after the Americas. Thailand has been hardest hit with more than 680 reported Zika infections this year, followed by Singapore with more than 450 and Vietnam with as many as 60.

Much of the population lives in the so-called “dengue belt,” where mosquito-borne diseases are prevalent. And vulnerable countries – including Vietnam, the Philippines, Pakistan and Bangladesh – are ill-prepared to handle an outbreak with any serious consequences, experts said.

Lacking evidence of varying degrees of virulence, public health officials have warned Asia leaders to prepare for the worst. The scientific community is following similar assumptions.

“Zika is Zika until proven otherwise. We assume that all Zikas are equally dangerous,” said Dr. Derek Gatherer, a biomedical expert at Lancaster University in Britain.

WHICH ZIKA?

The World Health Organization recognizes two major lineages of Zika. The first originated in Africa, where it was discovered in 1947 and has not been identified outside that continent. The Asian lineage includes strains that have been reported in Asia, the Western Pacific, Cabo Verde and, notably, the Americas, including Brazil.

The Asian lineage was first isolated in the 1960s in mosquitoes in Malaysia. But some studies suggest the virus has been infecting people there since the 1950s. In the late 1970s, seven cases of human infection in Indonesia were reported.

The first record of a widespread outbreak was in 2007 on Micronesia’s Island of Yap.

Experts began to suspect a link to birth defects during a 2013 outbreak in French Polynesia when doctors reported eight cases of microcephaly and 11 other cases of fetal malformation.

In 2015, it hit Brazil, causing spikes in an array of neurological birth defects now called congenital Zika virus syndrome, as well as Guillain-Barre syndrome, a neurological disorder that can lead to temporary paralysis.

Viruses mutate rapidly, which can lead to strains that are more contagious and more virulent. Many researchers theorized early on that the devastation in Brazil was caused by an Asian strain that had mutated dramatically.

That theory relies, among other things, on the absence of Zika-related microcephaly in Asia. So when Zika broke out in parts of Asia earlier this year, researchers were on the lookout.

If researchers were to connect a case of microcephaly to an older Asian strain – and not one that boomeranged back from Brazil — it would debunk the early theory. It would mean Zika “did not mutate into a microcephaly-causing variant as it crossed the Pacific,” Gatherer said.

At least three microcephaly cases have been identified in Asia, but the verdict is still out.

For two microcephaly cases in Thailand, public health officials could not determine whether the mothers had an older Asian strain of Zika or a newer one that returned from the Americas, said Dr Boris Pavlin, WHO’s acting Zika incident manager at a recent briefing.

In Vietnam, where there have been no reports of imported Zika infection, officials are investigating a third case of microcephaly. If it is linked to Zika, Pavlin said it would suggest the older strains there could cause microcephaly and, perhaps, Guillain-Barre.

In Malaysia, where at least six cases of Zika infection have been reported, authorities have identified both an older Southeast Asian strain and one similar to the strain in the Americas, suggesting the possibility that strains from both regions could be circulating in some countries.

The hunt is on in Africa as well. In Guinea-Bissau, five microcephaly cases are under investigation to determine whether the African lineage of Zika can cause microcephaly.

It is a top research priority at WHO, said Dr Peter Salama, executive director of the agency’s health emergencies program, in a press briefing Tuesday.

“That is a critical question because it has real public health implication for African or Asian countries that already have Zika virus transmission,” Salama said. “We are all following this extremely closely.”

 

HERD IMMUNITY

Scientists also are trying to learn whether people in places where Zika is endemic are protected by “herd immunity.” The phenomenon limits the spread of virus when enough of a population is inoculated against infection through vaccination, prior exposure or both.

Experts believe Zika moved explosively in the Americas because there was no prior exposure. It’s not clear how widely Zika has circulated in Africa and Asia, whether there could be pockets of natural immunity – and, importantly, whether immunity to one strain would confer immunity to another.

One recent review of studies suggests 15 to 40 percent of the population in some African and Asian countries may have been previously infected with Zika, said Alessandro Vespignani, a professor of health sciences at Northeastern University in Boston.

That’s far below the 80 percent population immunity one mosquito borne virus expert estimated in the journal Science would be necessary to block Zika.

Researchers also believe it’s possible that microcephaly went undetected in parts of Asia and Africa where birth defects weren’t well tracked.

That too, is under investigation, said Dr David Heymann, Chair of the WHO Emergency Committee, at a press briefing last week.

“Now,” he said, “countries are beginning to look back into their records to see on their registries what the levels of microcephaly have been.”

(Reporting by Julie Steenhuysen in Chicago and Amy Sawitta Lefevre in Bangkok; Additional reporting by Mai Nguyen and My Pham in Hanoi and Susan Heavey in Washington; Editing by Michele Gershberg and Lisa Girion)

Babies exposed to Zika developed microcephaly after birth

A 4-month-old baby born with microcephaly is held by his mother in front of their house in Olinda, near Recife, Brazil,

By Julie Steenhuysen

CHICAGO (Reuters) – Thirteen babies in Brazil born with normal head circumference have been diagnosed with congenital Zika syndrome, with brain scans showing extensive malformations, inflammation and reduced brain volume, researchers reported on Tuesday.

Of the 13 infants, 11 gradually developed the birth defect microcephaly, or abnormally small head size, in the months following birth.

The findings raise new concerns about the hidden effects of pre-natal exposure to the mosquito-borne Zika virus, which has been shown to cause birth defects when women become infected during pregnancy.

On Friday, the World Health Organization declared the global Zika emergency over because the link between Zika and microcephaly has been confirmed. WHO intends to continue studying Zika as a serious infectious disease that will require years of research.

Although others have observed neurological problems in infants exposed to Zika during gestation, the study is the first to carefully document birth defects in a group of babies with confirmed Zika exposure whose head circumference fell into the normal range at birth.

The study, published on Tuesday in the U.S. Centers for Disease Control and Prevention’s weekly report on death and disease, was done by teams in Recife and Fortaleza in northeastern Brazil.

Eleven of the infants were born with heads that were on the small side and were referred for evaluation shortly after birth. The remaining two, born with normal head circumferences, were referred for evaluation at 5 to 7 months because of developmental concerns.

Among the observed symptoms, 10 of the 13 babies had trouble swallowing, seven had epilepsy, five showed some degree of irritability, nine could not voluntarily move their hands and all had hypertonia, or excessively stiff muscle tone.

In a conference call with reporters on Tuesday, WHO officials said the fact that children can be born with normal head size but later develop microcephaly demonstrates that the definition of congenital Zika virus syndrome – the term WHO has associated with Zika-related birth defects – continues to expand.

Dr. Anthony Costello, WHO’s expert on maternal, newborn, child and adolescent health, said some 2,100 babies in Brazil have had confirmed cases of microcephaly related to Zika. He expects another 1,000 cases to be confirmed as doctors continue to investigate a backlog of suspected cases.

“We know the problem has not gone away in Brazil,” he said.

(Reporting by Julie Steenhuysen; Editing by Dan Grebler)

Zika striking women at higher rates than men: U.S. study

woman near Zika poster

By Julie Steenhuysen

CHICAGO (Reuters) – Adult women in Puerto Rico were significantly more likely to develop Zika than men, researchers said on Thursday, raising new questions about the potential role of sexual transmission of the virus from males to females.

The study, published in the U.S. Centers for Disease Control and Prevention’s weekly report on death and disease, evaluated more than 29,000 laboratory-confirmed cases of Zika since the outbreak began in Puerto Rico in November 2015.

The data show that of all Zika cases with laboratory evidence of infection, 62 percent were female. The results pattern similar observations from Brazil and El Salvador, the authors said.

One obvious explanation might be that pregnant women are more likely than men to seek treatment for Zika because of the potential risk of birth defects.

To account for that, the researchers excluded all pregnant women who tested positive for the virus. Of the remaining 28,219 non-pregnant women and men testing positive for Zika, 61 percent of these cases occurred in women over the age of 20.

The Zika findings differ from prior outbreaks in Puerto Rico of arboviruses transmitted by the same mosquitoes as Zika. For example, in the 2010 dengue outbreak and the 2014 chikungunya outbreak, infections were equally distributed among men and women.

“It is possible that male-to-female sexual transmission is a contributing factor to this skewing of the burden of disease toward women,” the CDC said in a statement summarizing the findings.

However, the contribution of sexual transmission to overall Zika rates is just beginning to be explored, the CDC said. It could be that women are more likely than men to seek care if they are sick, or that women are more likely to develop Zika symptoms if they become infected.

The CDC is conducting blood tests of individuals living near people with confirmed Zika to try to answer some of these questions.

Zika infections in pregnant women have been shown to cause microcephaly – a severe birth defect in which the head and brain are undersized – as well as other brain abnormalities. The connection between Zika and microcephaly first came to light last year in Brazil, which has since confirmed more than 2,000 cases of microcephaly.

(Reporting by Julie Steenhuysen; Editing by Andrew Hay)

Zika causes infertility, lasting harm to testes in mice: U.S. study

n aedes aegypti mosquito is pictured on a leaf in San Jose, Costa Rica

By Julie Steenhuysen

CHICAGO (Reuters) – A study of mice infected with Zika showed the virus caused lasting damage to key cells in the male reproductive system, resulting in shrunken testicles, lower levels of sex hormones and reduced fertility, U.S. researchers said on Monday.

So far, the findings are only in mice, but the result is worrisome enough to warrant further study because of possible implications for people, said Dr. Michael Diamond of Washington University in St. Louis, whose research was published in the journal Nature.

“It has to be corroborated,” Diamond, a professor of pathology, immunology and molecular microbiology, said in a telephone interview.

Much of the global effort to fight Zika has focused on protecting pregnant women from infection because of the grave implications for their unborn children.

Zika infections in pregnant women have been shown to cause microcephaly, a severe birth defect in which the head and brain are undersized, as well as other brain abnormalities.

Previous studies have shown that Zika can remain in semen for as long as six months. But little is known about whether prolonged exposure to the virus in the testes can cause harm.

To study this, Diamond and colleagues injected male mice with Zika. After a week, the researchers recovered infectious virus from the testes and sperm, and they found evidence of viral genes in certain cells of the testes. But overall, the testes appeared normal compared with other lab mice.

After three weeks, however, the differences were stark. The testes in the Zika-infected mice had shrunk to a tenth of their normal size, and the internal structure was destroyed.

“We saw significant evidence of destruction of the seminiferous tubules, which are important for generating new sperm,” Diamond said.

The researchers also found that Zika infects and kills Sertoli cells, which maintain the barrier between the bloodstream and the testes and foster sperm growth. Sertoli cells do not regenerate.

That raises the specter of long-lasting damage.

“The virus is infecting a site which doesn’t really renew if it gets damaged. That is the problem,” Diamond said.

Tests of testicular function showed sperm counts, sex hormones and fertility had dropped. Infected mice were four times less likely to impregnate a healthy female mouse than healthy males.

“This is the only virus I know of that causes such severe symptoms of infertility,” added Dr. Kelle Moley, a fertility specialist at Washington University and a study co-author.

There is no vaccine or treatment for Zika.

(Reporting by Julie Steenhuysen; Editing by Will Dunham)

New pool of Zika infested mosquitoes found in Florida

By Kami Klein

According to a Miami-Dade County Mosquito Control news release and Fox news health report, officials announced a new pool of Zika infested mosquitoes were trapped.  The news release says that officials learned about the new pool on Monday from trap 5 which is in the previously designated Zika transmission zone near Little Haiti.

The insects had been collected Oct. 5th.

A large portion of Miami Beach remains an active Zika infection zone. Officials announced last week that several people had been infected with Zika in a 1-square-mile area of Miami just north of the Little Haiti neighborhood.

According to the CDC Website, Zika is spread mostly by the bite of an infected Aedes species mosquito.  These mosquitoes bite both during the day and night.  There is no known vaccine or medicine for Zika but governments around the world are dedicating millions for research and a possible vaccine.  Zika can be passed from a pregnant woman to her fetus.  So far there have been 878 reported cases of pregnant women with the Zika virus in the United States and District of Columbia with 1,806 reported in U.S. Territories.

Zika infection during pregnancy can cause a birth defect of the brain called microcephaly and other severe fetal brain defects. Other problems have been detected among fetuses and infants infected with Zika virus before birth, such as defects of the eye, hearing deficits, and impaired growth. There have also been increased reports of Guillain-Barré syndrome, an uncommon sickness of the nervous system, in areas affected by Zika.

The following are the statistics of Zika cases as of October 6th, 2016.  The top states reporting most cases being travel associated are New York with 858 cases, Florida 708, California, 298 and Texas at 228.  Virtually every state has had reports of the Zika virus.

US States

  • Locally acquired mosquito-borne cases reported: 128
  • Travel-associated cases reported: 3,807
  • Laboratory acquired cases reported:  1
  • Total: 3,936
    • Sexually transmitted: 32
    • Guillain-Barré syndrome: 13

US Territories

  • Locally acquired cases reported: 25,871
  • Travel-associated cases reported: 84
  • Total: 25,955*
    • Guillain-Barré syndrome: 40

 

Find out more facts on the Zika virus including tips for keeping your family safe at the CDC Website .

 

 

 

 

 

U.S. health officials outline Zika spending priorities

County vector sprays neighborhood for mosquitos with Zika

WASHINGTON (Reuters) – U.S. health officials outlined on Tuesday how they planned to divide up $1.1 billion in funds approved by Congress to fight the Zika virus, including repaying $44.25 million they were forced to borrow from a fund allocated for other emergencies.

The funds were borrowed from the Public Health Emergency Preparedness cooperative, which helps state and local public health departments develop response plans to emergencies, while Congress battled over whether to supply the funds.

President Barack Obama in February requested $1.9 billion in emergency Zika funding. Congress approved $1.1 billion in September after months of political bickering.

On a conference call with reporters, health officials said$394 million would go to the U.S. Centers for Disease Control and Prevention, $152 million to the National Institutes of Health and $387 million for the Public Health and Social Services Emergency Fund, which supports the nation’s ability to respond to public health emergencies.

A further $40 million is aimed at expanding primary healthcare services in Puerto Rico and other U.S. territories, and $20 million for projects of national and regional significance in those areas.

Puerto Rico has been particularly hard hit by Zika, a mosquito-borne virus that has been linked with a rare birth defect known as microcephaly. The virus has spread to almost 60 countries and territories since the current outbreak was identified last year in Brazil.

As of Oct. 12, more than 29,000 cases of Zika infection had been reported in the United States and territories. Of those, more than 2,600 cases are in pregnant women. Nearly 26,000 of those cases are in Puerto Rico and other U.S. territories.

The government will be allocating funds, based on a competitive process, to support Zika virus surveillance and other programs. The funds will also be used to expand mosquito control, continue vaccine development and begin studies on the effect of Zika on babies born to infected mothers.

(Reporting by Toni Clarke in Washington; Editing by Peter Cooney)

Amid government silence, Venezuela’s microcephaly babies struggle

Ericka Torres holds her 3-months old son Jesus, who was born with microcephaly, at their home in Guarenas, Venezuela

By Alexandra Ulmer

GUARENAS, Venezuela (Reuters) – Deep inside a hilly Venezuelan slum, Ericka Torres rocks her three-month-old son Jesus to soothe his near-constant crying.

Jesus was diagnosed with microcephaly, a birth defect marked by a small head and serious developmental problems, after his mother contracted what was probably the mosquito-borne Zika virus during pregnancy in the poor city of Guarenas.

Torres said her boyfriend left after scans showed their child had birth defects, and she now struggles to afford medicine, clothes and even diapers for Jesus in the midst of Venezuela’s brutal economic crisis.

“It’s intense. But I can’t get stressed, because this struggle is only just beginning,” said Torres, 28, a supermarket security guard who smiles easily despite barely sleeping because of Jesus’ screams and convulsions, common traits of babies born with microcephaly.

The Venezuelan government, however, has not acknowledged a single case of Zika-related microcephaly in the country.

Beyond some health warnings and a handful of televised comments about Zika at the start of the year, the leftist government of President Nicolas Maduro has largely kept quiet about the virus even as neighboring Brazil and Colombia publish weekly bulletins.

Venezuela does provide data to the World Health Organization, which shows it has had some 58,212 suspected Zika cases and 1,964 confirmed ones since the virus emerged in Brazil last year and then spread rapidly through the Americas.

But it has not, however, declared any cases of confirmed congenital syndrome associated with Zika, such as microcephaly, and has not mentioned any suspected cases either.

To be sure, inadequate Zika testing has thwarted efforts to precisely diagnose Zika-caused microcephaly. But countries like Brazil have turned to clinical diagnoses and report “confirmed and probable cases” of Zika-associated congenital syndromes to the WHO, for instance.

Some doctors accuse Venezuela’s unpopular government of hiding the Zika problem amid a deep recession that has everything from flour and rice to antibiotics and chemotherapy medicines running short and spurred fierce criticism of Maduro.

They also say government inaction means kids are missing out on targeted state-sponsored therapy programs that would help to stimulate them.

“This delays the patient’s development, because no matter how much knowledge or drive you have, if you don’t have the physical tools like materials, resources, medicines, well that delays everything,” said Maria Pereira, a doctor in Caracas.

Local media have put the number of babies born with suspected Zika-linked microcephaly so far this year at around 60. Physicians in Caracas, the western city of Maracaibo, and the coastal state of Sucre, confirmed at least 50 cases in interviews with Reuters.

Venezuela’s Institute of Tropical Medicine estimates the real number could be much higher by the end of the year – between 563 and 1,400. That estimate is based on the numbers in Brazil, which has more than 1,800 confirmed cases, and pregnancy rates in Venezuela.

Product shortages have likely aggravated the effects of Zika in Venezuela: lack of contraceptives lead to unwanted pregnancies; lack of bug spray and fumigations lead to bites; and lack of anticonvulsant drugs or state support add to the hardships of children with the birth defect.

Venezuela’s health and information ministries did not respond to multiple requests for comment.

The government says it has one of the best health care systems in the world, pointing to free Cuban-staffed clinics in slums and social programs for maternal and child wellbeing. But it has stopped releasing data as the health sector has crumbled in the last two years.

‘NO RESOURCES’

Dozens of women and babies line up in the hot, dimly lit corridors of the J.M. de los Rios children’s hospital in Caracas, often waiting hours before an overstretched doctor can finally see them.

In the last three months, doctors say some 25 babies with microcephaly have been examined at what was once one of the leading hospitals in Latin America, with the majority of their mothers reporting symptoms including rashes or fevers during pregnancy.

Physicians order exams and prescribe therapies, but the overwhelmingly poor families struggle to scrape together enough money in the face of triple-digit inflation.

That delays early intervention and the discovery of other potential syndromes that have been linked to Zika, like vision problems or joint deformities.

“You feel impotent that you can’t provide anything more because there are no resources,” said Pereira, who works at the J.M. de los Rios hospital. Her family has to send her food and money from the provinces because she only earns around $70 a month between her salary and food tickets.

Other poor Latin American countries have also been criticized for their response to Zika. Brazil was called slow to investigate the initial surge of microcephaly cases and doctors say Zika prevention was spotty in Honduras, which estimates it will have some 340 cases of microcephaly by the end of the year.

Doctors and opposition lawmakers say Venezuela is faring the worst and have called for foreign aid and a stronger stance from the WHO.

Venezuela has rebuffed requests for aid, with officials saying it is an attempt to justify a foreign intervention in the oil-rich country.

When asked about criticism it was not doing enough in Venezuela, the WHO’s regional office for the Americas told Reuters its role was to provide technical cooperation to member countries and that it was working to strengthen that cooperation with Venezuela’s Health Ministry.

In the meantime, families are feeling the squeeze.

Home-based hairdresser Isabel Jimenez, her unemployed husband, and their four kids had already stopped having breakfast before the birth of Joshua, who has microcephaly, two weeks ago.

Now the family in the isolated Caribbean peninsula of Paraguana is under further pressure and has to rely on relatives for help with diapers, milk and medical appointments.

“I cried a lot,” said Jimenez, 28, of learning about Joshua’s condition. “At first I had a lot of anger and sadness, but I have to keep going with my baby because I can’t do anything else.”

(Additional reporting by Mircely Guanipa in Punto Fijo, Liamar Ramos and Daniel Kai in Caracas, Gustavo Palencia in Tegucigalpa, Ivan Castro in Managua, Paulo Prada in Rio de Janeiro, and Julia Symmes Cobb in Bogota; Writing by Alexandra Ulmer; Editing by Kieran Murray)

Florida declares new area of Zika transmission in Miami

avoid Zika ad on an airplane

By Julie Steenhuysen

(Reuters) – Florida officials on Thursday announced a new area of Zika transmission in the Miami region and have called on the federal government for funding to help fight the outbreak.

Florida Governor Rick Scott said state health officials have confirmed that local transmission of the mosquito-borne Zika virus is occurring in a new small area in Miami-Dade County, where the state believes two women and three men have been infected by the virus.

The governor said the state’s health department believes Zika transmission is only occurring in Miami-Beach and in the new area, which covers about 1 square mile (2.6 square km).

Zika, which is spread primarily by mosquitoes but also sexually, is a concern for pregnant women and their partners because the virus has been liked with a series of birth defects including microcephaly, marked by small head size and underdeveloped brains that can lead to severe developmental problems in babies.

Last month, U.S. health officials urged pregnant women to consider putting off all nonessential travel to Miami due to the Zika virus even as the state lifted a travel warning for the Wynwood, the Miami neighborhood which was the first site of local Zika transmission in the continental United States.

Florida has reported a total of 164 cases of Zika caused by local mosquito transmission, including 19 people who were infected in the state but live elsewhere. There are also five cases in which it was not clear whether transmission occurred in Florida or elsewhere.

In a statement released on Thursday, Scott said the announcement of the new area of transmission underscores the “urgent need” for federal funding to fight the virus, adding that the state still has not received any of the funding that was approved by Congress and signed by President Barack Obama two weeks ago.

Scott said he has asked the U.S. Centers for Disease Control and Prevention to work directly with the Miami-Dade Mosquito Control District to identify best practices for defeating Zika in the new area.

Florida officials had already reported four of the five cases of Zika that occurred in the new area of transmission in Miami-Dade County. “With the confirmation of today’s case, this area now meets the CDC’s criteria for a new zone,” officials said in a statement.

The Zika virus was first detected in Brazil last year and has since spread across the Americas. It has been linked to more than 1,800 cases of microcephaly in Brazil.

(Reporting by Julie Steenhuysen in Chicago; Editing by Lisa Shumaker)

Zika vaccine race spurred by crisis and profit potential

Research scientist Dan Galperin works in the research laboratory at Protein Sciences Inc. where they are working on developing a vaccine for the Zika virus i

By Bill Berkrot

NEW YORK (Reuters) – The race to find protection against the Zika virus is fueled by something often missing from tropical disease research: the potential for big profit.

The prospect of a blockbuster vaccine against a mosquito-borne virus has accelerated the pace of development and attracted the interest of big drugmakers, including Sanofi, GlaxoSmithKline Plc and Takeda Pharmaceuticals.

Although Zika infections are mild or asymptomatic in most people, demand for a vaccine is expected to be strong because it can cause devastating birth defects, pharmaceutical executives and disease experts said.

The most lucrative market is seen in travelers seeking inoculation against the virus that has moved rapidly across the Americas and is the only mosquito-borne disease also spread through sex.

“It scares people,” said Scott Weaver, a virologist with the University of Texas and chairman of the Zika task force for the Global Virus Network. “Europeans and Americans can pay a pretty high price for these kinds of vaccines.”

A vaccine could come to market in as little as two years. Even if the current outbreaks in Latin America and the Caribbean burn out by that time, people living in those regions are expected to want protection against a return of Zika.

Tens of millions of travelers from United States and other wealthy nations, including people on business trips with corporate-sponsored health coverage, are expected to get vaccines before visiting areas where Zika is circulating.

“If you consider just a portion of the U.S. traveler population, we can conservatively envision a Zika market opportunity exceeding $1 billion” a year, said Joseph Kim, chief executive of Inovio Pharmaceuticals, a Pennsylvania company that is farthest along in the development path with human testing of a vaccine candidate underway in hard hit Puerto Rico.

Drugmakers and disease experts also envision the vaccine becoming standard care for girls before puberty to guard against birth defects in future pregnancies. Boys also could be candidates to protect eventual sexual partners.

“Hopefully a vaccine can be developed that’s sold for a low cost in endemic areas,” Weaver said.

ZIKA’S DIFFERENCE

Blockbuster sales for vaccines against mosquito-borne viruses are unheard of. Sanofi’s dengue vaccine, approved in nine countries, is generating near-blockbuster expectations, the biggest in the market by far. Analysts forecast annual sales for Dengvaxia reaching about $900 million by 2020, according to Thomson Reuters data.

Efforts to find a malaria vaccine are purely philanthropic. The Bill and Melinda Gates Foundation has contributed significantly to GSK’s decades-long effort to produce a vaccine for children in Africa. Development is ongoing, and GSK expects no profit.

The U.S. National Institutes of Health (NIH) developed a potential vaccine for West Nile virus, but it failed to find a commercial partner because the virus did not inspire enough public alarm to generate big sales. West Nile leads to serious complications in less than 1 percent of people infected.

In February, the World Health Organization declared a global public health emergency because of Zika’s apparent link to microcephaly, a birth defect marked by small heads and serious developmental problems. That, and evidence of other severe fetal brain abnormalities linked to Zika, have galvanized efforts to speed vaccine development.

The NIH is negotiating with companies to produce Zika vaccines but has its own pilot plant that can make enough for early clinical testing, which began with its first candidate in August.

“We’re not dependent on a company until you prove it works and then you need somebody to manufacture millions of doses,” said Dr. Anthony Fauci, director of the NIH’s National Institute of Allergy and Infectious Diseases (NIAID).

The first NIH candidate is a DNA vaccine containing no actual virus, in which genetically engineered cells produce an antigen that triggers an immune response, similar to the West Nile vaccine. By early 2017, the agency expects to be able to decide whether to begin enrolling thousands of patients in an efficacy study, or move on to the next candidate.

The size of the Zika outbreak may help development efforts. If it remains widespread, it will be easier to tell if a vaccine is effective.

“If the infections die down, then it’s going to take much longer to find out if it works,” Fauci said.

A second NIH candidate contains inactivated viral material, while a third utilizes attenuated, or weakened, live virus.

DNA-based candidates are most likely to prove safe, but they typically require multiple doses to work. Vaccines that contain live virus are considered most effective with one dose, but have a far higher safety hurdle, particularly if they are intended for pregnant women, and so they take longer to get to market.

INDUSTRY PILES IN

Inovio’s DNA vaccine is injected along with a brief low voltage electronic pulse that induces cell membranes to open, making them more receptive, in theory, to accepting the vaccine’s genetic material.

Privately-held Protein Sciences Corp built its Zika vaccine using technology similar to its already approved Flublok flu vaccine. The drugmaker has partnerships with companies in Argentina, Brazil, Japan and Mexico and plans to seek funding from Brazil and the NIH. It expects to start human trials by January.

Chief Executive Manon Cox estimated the cost of developing and securing approval for a vaccine could be as high as $1 billion. Without government funding, “that product has got to have a market of a few billion dollars,” she said.

With the help of $43 million in initial funding from the U.S. government, France’s Sanofi is developing a candidate using live attenuated virus. The company is not as far along as some other efforts, but it aims to start human trials next year and is confident it can catch up.

“We’ve got technologies, infrastructure, experience dealing with regulators in this field. All of that gives us a jumpstart,” said Nick Jackson, head of research for Sanofi’s vaccine unit.

Another French vaccine maker, Valneva SE, generated an inactivated Zika vaccine candidate using the same process as its already approved Japanese encephalitis vaccine.

GSK is working with NIAID on a new type of vaccine technology. Japan’s Takeda also secured U.S. government funding to help develop a vaccine using killed Zika virus and plans to begin human testing in the second half of 2017.

“If there is a huge need,” said Dr. Rajeev Venkayya, president of Takeda’s global vaccine unit, “there will be a business model that works.”

(Reporting by Bill Berkrot; Editing by Michele Gershberg and Lisa Girion)

Thailand confirms first Zika-linked microcephaly in Southeast Asia

City worker fumigates area to get rid of mosquitoes carrying Zika

By Aukkarapon Niyomyat

BANGKOK (Reuters) – Thailand reported on Friday the first confirmed cases in Southeast Asia of microcephaly linked to mosquito-borne Zika, as the World Health Organization urged action against the virus across the region.

The confirmation of two case of microcephaly, a birth defect marked by small head size, came a day after U.S. health officials recommended that pregnant women postpone non-essential travel to 11 Southeast Asian countries because of the risk of Zika.

“We have found two cases of small heads linked to Zika, the first cases in Thailand,” Prasert Thongcharoen, an adviser to the Department of Disease Control, told reporters in Bangkok.

He declined to say where in Thailand the cases were found but officials have said they were not in Bangkok.

The World Health Organisation (WHO) said the cases were the first of Zika-linked microcephaly in Southeast Asia and the virus infection represented a serious threat to pregnant women and their unborn children.

“Countries across the region must continue to strengthen measures aimed at preventing, detecting and responding to Zika virus transmission,” Dr Poonam Khetrapal Singh, the WHO’s regional director, said in a statement.

U.S. health officials have concluded that Zika infections in pregnant women can cause microcephaly, which can lead to severe developmental problems in babies.

VIRUS SPREADING

The connection between Zika and microcephaly first came to light last year in Brazil, which has confirmed more than 1,800 cases of microcephaly that it considers to be related to Zika infections in the mothers.

Zika has spread extensively in Latin American and the Caribbean over the past year or so, and more recently it has been cropping up in Southeast Asia.

Thailand has confirmed 349 Zika cases since January, including 33 pregnant women, and Singapore has recorded 393 Zika cases, including 16 pregnant women.

Some health experts have accused Thai officials of playing down the risk of Zika to protect its thriving tourist industry, but Prasert dismissed that.

“Thailand is not hiding anything and is ready to disclose everything,” he said, adding that other countries in Southeast Asia might also have cases of Zika-linked microcephaly that they have not disclosed.

The WHO said Thailand’s response was an example for the region.

“Thailand’s diligence underscores the commitment of health authorities to the health and wellbeing of the Thai public, and provides a positive example to be emulated,” Singh said.

The U.S. Centers for Disease Control and Prevention (CDC) said on Thursday people should consider postponing travel to Brunei, Myanmar, Cambodia, Indonesia, Laos, Malaysia, Maldives, Philippines, Thailand, Timor-Leste (East Timor), and Vietnam.

The CDC has already issued a “travel notice” for Singapore, and said such a warning would be considered for the new countries if the number of cases rose to the level of an outbreak.

Thailand’s confirmation of Zika-linked microcephaly comes ahead of China’s week-long “Golden Week” holiday with Thailand expecting 220,000 Chinese visitors, up from 168,000 for the week in 2015, Tourism Authority of Thailand governor Yuthasak Supasorn told Reuters.

NO VACCINE

There is no vaccine or treatment for Zika. An estimated 80 percent of people infected have no symptoms, making it difficult for pregnant women to know whether they have been infected.

There are also no specific tests to determine if a baby will be born with microcephaly, but ultrasound scans in the third trimester of pregnancy can identify the problem, according to the WHO.

Zika is commonly transmitted through mosquitoes but can also be transmitted sexually.

Another Thai health ministry adviser urged everyone to work to stop the spread of mosquitoes but said people should not panic.

“Don’t have sex with a Zika-infected person. If you don’t know if they are infected, then use a condom,” the adviser, Pornthep Siriwanarangsan, told reporters. “We can’t stop women from becoming pregnant … but we mustn’t panic.”

Health authorities in the region said they were stepping up monitoring, but there has been little testing and officials said the real number of cases was bound to be higher than the confirmed figure.

“We do not test everybody, we test only those who are symptomatic,” said Paulyn Jean Rosell-Ubia, health secretary in the Philippines, which has reported 12 Zika cases.

“Yes, we are positive that the number is higher because we are not testing everyone.”

Malaysia, which has reported six cases of Zika, including two in pregnant women, said it would seek information from Thailand on the particular strain of the Zika virus there.

“We are taking serious notice of the reports in Thailand, and we will reach out to the Thai authorities for more information … so that we can be more prepared,” Malaysia’s health minister, Subramaniam Sathasivam, told Reuters.

Authorities in Vietnam, which has reported three cases of Zika, ordered stepped up monitoring of pregnant women.

In Indonesia’s capital, Jakarta, head of disease outbreak and surveillance Dwi Oktavia said there had been no sign of any increase in birth defects there. Indonesia had one Zika case in 2015 but has confirmed none since then.

Microcephaly in babies can lead to respiratory problems related to malformation of the brain, a serious threat to the lives of babies. Children with microcephaly face lifelong difficulties, including intellectual impairment.

Zika was first identified in Uganda in 1947 and first isolated in Asia in the 1960s. It was unknown in the Americas until 2014.

(Additional reporting by Amy Sawitta Lefevre, Juarawee Kittisilpa and Panarat Thepgumpanat, Kanupriya Kapoor in JAKARTA, Roxanna Latiff in KUALA LUMPUR, Karen Lima in MANILA and Pham Thi Huyen My in HANOI; Writing by Robert Birsel; Editing by Alex Richardson)