Washington, DC - Researchers at the National Center for Advancing Translational Sciences (NCATS) recently identified compounds that potentially can be used to inhibit Zika virus replication and reduce its ability to kill brain cells. These compounds now can be studied by the broader research community to help combat the Zika public health crisis. NCATS is part of the National Institutes of Health.

Using NCATS’ drug repurposing screening robots, researchers identified two classes of compounds effective against Zika: one is antiviral, and the other prevents Zika-related brain cell death. The compounds include emricasan, an investigational drug currently being evaluated in a clinical trial to reduce liver injury and fibrosis, and niclosamide, a U. S. Food and Drug Administration-approved drug for use in humans to treat worm infections. In addition, the researchers identified nine cyclin-dependent kinase (CDK) inhibitors. CDK usually is involved in regulation of cellular processes as well as normal brain development, but the Zika virus can negatively affect this process.

NCATS’ work was a collaborative effort with Johns Hopkins University, Baltimore, (JHU) and Florida State University, Tallahassee, (FSU), and the study results were published in the August 29 issue of Nature Medicine. The NCATS screening effort builds on the initial research by JHU and FSU scientists, who discovered that the Zika virus infects brain cells early in development. Infection by the Zika virus may be related to fetal microcephaly, an abnormally small head resulting from an underdeveloped and/or damaged brain.

The Zika virus has been reported in 60 countries and territories worldwide; currently, there are no vaccines or effective drug treatments. The virus is spread primarily through bites from infected Aedes aegypti mosquitoes, and in addition, can be transmitted from mother to child and through sexual contact. It also is associated with neurological diseases such as Guillain-Barré syndrome in infected adults.

“The Zika virus poses a global health threat,” said Anton Simeonov, Ph.D., NCATS scientific director. “While we await the development of effective vaccines, which can take a significant amount of time, our identification of repurposed small molecule compounds may accelerate the translational process of finding a potential therapy.”

NCATS researcher Wei Zheng, Ph.D., and his team led the drug repurposing screen to test three strains of Zika: Asian, African and Puerto Rican. The scientists first developed an assay (test) using caspase 3, a protein that causes brain cell death when infected by the virus. The next step was screening 6,000 FDA-approved and investigational compounds, which resulted in the identification of more than 100 promising compounds. The team then evaluated the protective effect of these compounds in brain cells after Zika virus infection. Three lead compounds, emiracsan, niclosamide and a CDK inhibitor known as PHA-690509, were identified as reducing neuronal cell death caused by Zika virus infection.

These compounds were effective either in inhibiting the replication of Zika or in preventing the virus from killing brain cells. For example, emricasan prevents cell death, and niclosamide and the nine CDK inhibitors stop the virus’ replication. The team also found that emricasan, when combined with one of the CDK inhibitors, prevented both cell death and virus replication. In addition, the team noted that the CDK inhibitors may be useful in treating non-pregnant patients who face an increased risk of Guillain-Barré syndrome and other conditions sparked by Zika infection.

The researchers cautioned, however, that the use of emricasan and niclosamide during pregnancy for Zika infection will need to be evaluated in pre-clinical toxicology studies and clinical trials.

“Using the NCATS drug repurposing platform for emerging infectious diseases can help rapidly identify potential treatments for urgent needs such as the Zika virus,” Zheng said. “While identifying promising compounds is a first step, our goal at NCATS is to facilitate the translation of these findings for evaluation in the clinic. The release of all the compound screening data in this publication and in the public PubChem database opens the door to the research community to do just that.”

NCATS’ screening effort enabled the broader research team to quickly translate their earlier discoveries toward work to develop treatments for Zika virus infection. JHU is working on a mouse model to study the neuroprotective effects of the compounds identified from the screen and studying the mechanism of action of the lead compounds. FSU is testing the efficacy of these compounds in a Zika virus mouse model and is also studying the mechanism of action of the lead compounds.

In addition to NCATS, FSU and JHU, the research was supported by Emory University, Atlanta; the Maryland Stem Cell Research Fund, Columbia; NIH’s National Institute of Neurological Disorders and Stroke through grants NS048271 and NS095348, NS047344 and NS097206; and NIH’s National Institute of Allergy and Infectious Diseases through grant AI119530.</s>SINGAPORE, Aug 30 (Reuters) - Singapore confirmed 26 more cases of locally-transmitted Zika infections on Tuesday, bringing the tally to 82, local media reported, citing the health ministry and National Environment Agency.

Of these, five cases were detected in parts of Singapore outside the Aljunied area where all the previous cases were found, media reported.

The Zika virus was detected in Brazil last year and has since spread across the Americas. It poses a risk to pregnant women because it can cause severe birth defects. (Reporting by Marius Zaharia; Editing by Ian Geoghegan)</s>Hong Kong (CNN) The Zika virus is on a rampage in Singapore, with 82 locally-transmitted cases confirmed late Tuesday by the country's Ministry of Health (MOH).

The MOH warns that the figures are likely set to rise, but why is Zika spreading so fast in the city state?

"The proportion of our population that are immune to the Zika virus is likely to be low in Singapore and if you don't have the immunity to provide the roadblocks, then it's likely that the virus will spread fast," Ooi Eng Eong, the deputy director of the Emerging Infectious Disease program at Duke-NUS Medical School in Singapore, told CNN.

Everything you need to know about Zika

Everything you need to know about Zika 01:42

Everything you need to know about Zika

The majority of reported cases are among foreign construction workers based in the residential Aljunied Crescent neighborhood in Singapore. Though cases were limited to this area on Monday, by late Tuesday the MOH reported 26 new cases that showed how the Zika virus had spread to nearby residential areas, raising concerns that the virus could travel even further afield.

While Malaysia and Indonesia announced they would be implementing additional passenger screening procedures at its airports, foreign ministries in the US, Australia, Taiwan and South Korea have all issued alerts, advising pregnant women against traveling to Singapore.

Singapore is known to suffer widely from dengue virus, a mosquito-borne tropical disease that triggers high fevers, headaches, vomiting and skin rashes in those infected.

In 2016, the MOH announced that it expected as many as 30,000 cases in the country.

Ooi explained that the Zika virus' rapid spread in Singapore was likely down to its similarities with the dengue virus.

"Zika is very closely related to dengue. It has all the genetic traits that would allow it to spread where dengue thrives -- the virus can infect and spread through the same Aedes aegypti mosquitoes that spread dengue virus," said Ooi.

With its 5.7 million-strong population packed mostly in crowded urban areas, containing Zika's spread in Singapore is a challenge.

"In Singapore, many people live in densely packed apartment blocks so it's easy for high numbers of people to get infected even if there are only a few mosquitoes flying around," explained Ooi.

As of August 29, Singapore's MOH had screened roughly 5,000 premises out of an estimated 6,000 in the Aljunied Crescent neighborhood to check for mosquito breeding grounds. So far, the agency has detected and destroyed 39 breeding habitats.

The MOH is also urging local residents to play an active role in stopping Zika's spread by distributing information leaflets and advising residents to apply repellent as a precaution.

Jaspar Fuk-Woo Chan, an infectious disease specialist and assistant professor at the University of Hong Kong, supported the MOH's efforts to reduce Zika's spread in Singapore.

"The government are making information on the Zika virus' spread readily available. They've also reacted very quickly to the first local cases by collecting information on the infected people," Chan told CNN.

He added, however, that it would take several weeks to grasp the extent of the outbreak. In the meantime, efforts to curb Zika's spread in the city state, he said, hinged on all citizens using insect repellent and making sure there were no potential mosquito breeding areas around their residential areas.

'Repellents are flying off the shelves'

In a joint statement released Wednesday, Singapore's MOH and the the Clinical Advisory Group (CAG) advised all pregnant women with symptoms of Zika, or with Zika-positive male partners to be tested for the infection.

But not every woman is letting the recent outbreak get to them.

"I'm conscious that I have to be more careful now," Su San, a 30-year-old mother trying for a second child, told CNN. "I'm applying ointments so that I don't get bitten, but I haven't put my plans to have another child on hold."

Rather than locking herself indoors, San said she would avoid areas like parks where mosquitoes were likely to be, and spend recreational time in libraries and museums instead.

For others, the Zika outbreak in Singapore has become an unlikely boon.

Theodore Khng, CEO of mosquito repellent startup Theo10, told CNN that sales of his natural deet-free product had tripled in the last three days.

Khng initially manufactured his product to combat mosquitoes carrying the dengue virus, but admitted that the recent Zika scare had boosted sales.

"People who have used the products before have been buying in bulk for others," said Khng. "The repellents are flying off the shelves."</s>Moving from Africa to French Polynesia to Central and South America, the disease is now active in the US and Asia, and is likely to continue to spread.

Zika arrives in a country via the bloodstream of hundreds of globe-trotting vacationers and business people, all returning home from areas where Zika is actively circulating. It's not like you can stop it -- four out of five people with Zika have no symptoms, so most of those passengers are unaware they carry the virus in their blood.

Everything you need to know about Zika

Everything you need to know about Zika 01:42

Everything you need to know about Zika

No country is immune from a potential outbreak, as long as the mosquitoes capable of spreading the virus -- Aedes aegypti and the Aedes albopictus -- live there.

Some have called Zika the world's newest STD.

Why it's serious

Scientists have learned a lot about Zika in the last year. For one, the virus appears to have mutated as it has spread across the world.

When it first emerged, inconspicuously, from Uganda's Zika forest in 1947, the effects of infection were mild, nothing worse than a mild cold or flu. While that's still true for many today, for others, the consequences of Zika are devastating. Babies are being born with life-altering brain damage to women infected with Zika during their pregnancies; immune-compromised adults are dying of complications, and a Zika-triggered auto-immune disorder called Guillain-Barré attacks the nervous system, causing temporary paralysis, and even death.

Vaccine on the way?

No vaccine currently exists. Even though several private and governmental agencies have various versions in the works, the likelihood of having a vaccine ready for public consumption is a year or two away -- possibly even more.

How long those trials may take, says Fauci, is determined by the number of Zika infections in a community when the vaccine is ready.

"If it's explosive in an area, then you can get an answer within one and a half years," Fauci adds, "but if the cases slow down it might take us additional three to four years to determine if it works."

With a vaccine only a promise on the horizon, researchers are also looking at ways to treat the virus while it's circulating in the blood.

A number of groups are screening thousands of existing drugs, already approved for human use by the Food and Drug Administration, to see if any might be effective against the Zika virus.

"Because [it] is blocking the multiplication of the viral genetic material, the compound is equally effective even when added several hours after the cells are exposed to the virus," Tang adds.

While scientists scramble to vaccinate and treat, mosquito control officials are doing their utmost to tackle the virus at its source: the mosquitoes themselves.

Traditional control techniques emphasize removing standing water, spraying pesticides and larvicides, and encouraging home owners to keep screens on their doors and windows. That, along with the widespread use of air-conditioning, make it much easier for developed countries like the US to keep outbreaks contained -- it's much harder in poor, economically disadvantaged countries.

Another factor straining traditional control efforts is the female Aedes aegypti mosquito, who is primarily responsible for this global spread. A crafty creature, she is an aggressive daytime biter, who prefers to live close to her favorite blood meal, humans. Over the centuries, she has adapted to urban environments, preferring stagnant water and small containers such as plastic cups, potted plants and discarded tires to lay her eggs.

A 'sip feeder,' this blood sucker likes to bite multiple people, taking just a 'sip' of blood each time, thus increasing the number of people she can infect in just one feeding. A tiny creature, her bite is almost painless.

Once you add that to her tendency to sneak up on victims, often biting on ankles and the back of elbows, you can see how easy it might be for her to feed without a life-threatening slap.

That's the worry for Brazil and other South and Central American countries, currently experiencing a drop in Zika cases during the drier winter months. When the rains begin again this fall, those eggs will hatch and cases could begin to rise, along with the associated risk to pregnant women and their undeveloped fetuses.

In the meantime, Zika continues its travels, hitch hiking in traveler's blood and via the occasional mosquito hidden in an industrial shipment of goods.

Whether the virus will take hold in a country depends on the local environment and a country's ability to combat the threat.

The first case of locally-transmitted Zika in the US was a surprise. Instead of occurring from a mosquito bite, the virus was sexually transmitted by a man recently returned from a country with an active outbreak.

Then in mid-July a Miami mosquito bit a returning traveler, processed the virus, and began spreading it in Wynwood, a 1-square-mile Miami neighborhood. Despite massive control efforts, one or two cases also popped up in Miami Beach and in the Tampa/St. Petersburg area.

To date, there are 43 cases of locally transmitted Zika in Florida.

That number pales in comparison to hard-hit Puerto Rico, which has over 13 thousand cases of the virus, with more than a thousand of those affecting pregnant women. An economic downturn, failing health care system, and inadequate financial support from the mainland makes it difficult for Puerto Rico to fight their epidemic.

Other Caribbean countries also continue to battle Zika as their outbreaks continue. The WHO says Martinique currently has 10 cases of microcephaly, while just this week the first babies with microcephaly were reported in Haiti, one, and the Dominican Republic with three cases.

Brazil continues to be the country hardest hit by Zika, with thousands infected and over 1800 babies diagnosed with microcephaly. That number doesn't count the babies with normal sized heads that might develop vision, hearing and developmental issues from their Zika exposure as they grow.

Other Central and South American countries are also struggling with the fallout from the virus.

Columbia reports 29 cases of microcephaly in newborns, Panama has 5 cases, El Salvador 4, French Guiana 3, Paraguay 2, while Honduras and Costa Rica report one case each.

The good news for South America is that colder winter weather and dry skies have reduced the number of new Zika cases. In fact the WHO just announced no laboratory-confirmed cases of Zika related to the Olympics, which ended on August 21 in Brazil, and Chile hasn't reported a new case of Zika this year.

So far, Europe has been spared much of Zika's devastation. Despite a number of imported cases from returning travelers, only Slovenia and Spain report cases of microcephaly --one each -- says WHO.

Southeast Asia has been hard hit by Zika, and officials worry numbers are vastly under reported. Singapore just announced 41 cases of locally acquired Zika infection, but the WHO also lists Indonesia, Thailand, the Philippines and Vietnam as "countries with possible endemic transmission or evidence of local mosquito-borne Zika infections in 2016."

Cambodia has reported cases in the past, but the WHO has the country on its list of countries where the outbreak has either been "terminated" or is "without documentation" in 2016. Other countries that fit that positive category include French Polynesia, the site of a large outbreak in 2013, Lao People's Democratic Republic, Malaysia, the Cook Islands, the Maldives, New Caledonia, Papua New Guinea, the Solomon Islands and Vanuatu.

Cape Verde, a small island located 350 miles off the western coast of Africa, is reporting 9 cases of microcephaly. Other than that, Africa, the birthplace of Zika, is not reporting any outbreaks of Zika at this time.

CNN has compiled the full list of countries and territories with current outbreaks of Zika, according to the CDC and WHO.

Those affected are: Anguilla, Antigua and Barbuda, Argentina, Aruba, Bahamas, Barbados, Belize, Bolivia, Bonaire, Brazil, Cayman Islands, Colombia, Costa Rica, Cuba, Curacao, Dominica, Dominican Republic, Ecuador, El Salvador, Fiji, French Guiana, Grenada, Guadeloupe, Guatemala, Guyana, Haiti, Honduras, Jamaica, Kosrae (an Island of the Federated States of Micronesia), Maldives, Marshall Islands, Martinique, Mexico, New Caledonia, Nicaragua, Panama, Papua New Guinea, Paraguay, Peru, Puerto Rico, Saba, Saint Barthelemy, Saint Lucia, Saint Martin, Saint Vincent and the Grenadines, Sint Maarten, Sint Eustatius, Suriname, Trinidad and Tobago, Turks and Caicos, United States of America*, U.S. Virgin Islands, Venezuela, Vietnam, American Samoa, Samoa, Tonga and Cape Verde.</s>Hong Kong (CNN) The Zika virus is on a rampage in Singapore, with 82 locally-transmitted cases confirmed late Tuesday by the country's Ministry of Health (MOH).

The MOH warns that the figures are likely set to rise, but why is Zika spreading so fast in the city state?

"The proportion of our population that are immune to the Zika virus is likely to be low in Singapore and if you don't have the immunity to provide the roadblocks, then it's likely that the virus will spread fast," Ooi Eng Eong, the deputy director of the Emerging Infectious Disease program at Duke-NUS Medical School in Singapore, told CNN.

Everything you need to know about Zika

Everything you need to know about Zika 01:42

Everything you need to know about Zika

The majority of reported cases are among foreign construction workers based in the residential Aljunied Crescent neighborhood in Singapore. Though cases were limited to this area on Monday, by late Tuesday the MOH reported 26 new cases that showed how the Zika virus had spread to nearby residential areas, raising concerns that the virus could travel even further afield.

While Malaysia and Indonesia announced they would be implementing additional passenger screening procedures at its airports, foreign ministries in the US, Australia, Taiwan and South Korea have all issued alerts, advising pregnant women against traveling to Singapore.

Singapore is known to suffer widely from dengue virus, a mosquito-borne tropical disease that triggers high fevers, headaches, vomiting and skin rashes in those infected.

In 2016, the MOH announced that it expected as many as 30,000 cases in the country.

Ooi explained that the Zika virus' rapid spread in Singapore was likely down to its similarities with the dengue virus.

"Zika is very closely related to dengue. It has all the genetic traits that would allow it to spread where dengue thrives -- the virus can infect and spread through the same Aedes aegypti mosquitoes that spread dengue virus," said Ooi.

With its 5.7 million-strong population packed mostly in crowded urban areas, containing Zika's spread in Singapore is a challenge.

"In Singapore, many people live in densely packed apartment blocks so it's easy for high numbers of people to get infected even if there are only a few mosquitoes flying around," explained Ooi.

As of August 29, Singapore's MOH had screened roughly 5,000 premises out of an estimated 6,000 in the Aljunied Crescent neighborhood to check for mosquito breeding grounds. So far, the agency has detected and destroyed 39 breeding habitats.

The MOH is also urging local residents to play an active role in stopping Zika's spread by distributing information leaflets and advising residents to apply repellent as a precaution.

Jaspar Fuk-Woo Chan, an infectious disease specialist and assistant professor at the University of Hong Kong, supported the MOH's efforts to reduce Zika's spread in Singapore.

"The government are making information on the Zika virus' spread readily available. They've also reacted very quickly to the first local cases by collecting information on the infected people," Chan told CNN.

He added, however, that it would take several weeks to grasp the extent of the outbreak. In the meantime, efforts to curb Zika's spread in the city state, he said, hinged on all citizens using insect repellent and making sure there were no potential mosquito breeding areas around their residential areas.

'Repellents are flying off the shelves'

In a joint statement released Wednesday, Singapore's MOH and the the Clinical Advisory Group (CAG) advised all pregnant women with symptoms of Zika, or with Zika-positive male partners to be tested for the infection.

But not every woman is letting the recent outbreak get to them.

"I'm conscious that I have to be more careful now," Su San, a 30-year-old mother trying for a second child, told CNN. "I'm applying ointments so that I don't get bitten, but I haven't put my plans to have another child on hold."

Rather than locking herself indoors, San said she would avoid areas like parks where mosquitoes were likely to be, and spend recreational time in libraries and museums instead.

For others, the Zika outbreak in Singapore has become an unlikely boon.

Theodore Khng, CEO of mosquito repellent startup Theo10, told CNN that sales of his natural deet-free product had tripled in the last three days.

Khng initially manufactured his product to combat mosquitoes carrying the dengue virus, but admitted that the recent Zika scare had boosted sales.

"People who have used the products before have been buying in bulk for others," said Khng. "The repellents are flying off the shelves."</s>Adult female mosquitoes can pass the Zika virus along to their offspring, new research reveals.

Experts warn this means the virus will be much harder to control than previously thought.

The finding makes clear the need for pesticide programs that kill both adult mosquitoes and their eggs.

Current methods are not adequate, warns study co-author Dr Robert Tesh of the University of Texas.

'Spraying affects adults, but it does not usually kill the immature forms - the eggs and larvae,' he said.

'Spraying will reduce transmission, but it may not eliminate the virus.'

The findings were published in the American Journal of Tropical Medicine and Hygiene on Monday.

Scientists were comforted by the similarities they found between Zika and well-understood viruses like dengue and yellow fever.

Like Zika, those two infections can be transmitted from female mosquitoes to their offspring.

But more extreme measures will have to be taken to tackle Zika since it is new to the US and very few - if anyone - have build up resistance to the virus.

Although Zika generally causes mild disease in adults, it is a major threat to pregnant women because it has been shown to cause the severe birth defect known as microcephaly and other brain abnormalities.

The ongoing Zika outbreak was first detected last year in Brazil, where it has been linked to more than 1,800 cases of microcephaly, and has since spread rapidly through the Americas.

Aedes aegypti, the mosquitoes that carry Zika, lay eggs in small containers of water.

Homeowners have been advised to dump out containers of water on their properties.

When the water is dumped, the eggs cling in a ring around the water line, where they remain dormant until the next rain, when they can hatch.

Scientists studying Zika wanted to find out whether some of the offspring from these tropical mosquitoes might carry the virus, helping to perpetuate an outbreak during dry seasons.

To find out, researchers injected female Aedes aegypti mosquitoes raised in a laboratory with Zika.

They were then fed, and within a week, they laid eggs.

The team collected and cared for the eggs until they hatched into adult mosquitoes, and counted the ones that carried the Zika virus.

They found the virus present in one out of every 290 mosquitoes tested.

'The ratio may sound low,' Tesh said, 'but when you consider the number of Aedes aegypti in a tropical urban community, it is likely high enough to allow some virus to persist, even when infected adult mosquitoes are killed.'

Tesh said the next step is to show that mosquitoes are actually passing Zika to their offspring in the wild.

Experts fighting Zika in the Wynwood neighborhood of Miami have announced aerial spraying campaigns using pesticides that kill both adult mosquitoes and mosquito larvae.

For homeowners in affected areas, Tesh advised people to dump standing water from containers on their property and scrub them thoroughly to remove eggs and larvae. They should also remove any objects from their yards that could collect water.

WHAT YOU NEED TO KNOW ABOUT ZIKA The Zika (ZEE'-ka) virus was first discovered in monkey in Uganda in 1947 - its name comes from the Zika forest where it was first discovered. It is typically transmitted through bites from the Aedes species of mosquitoes. They are aggressive feeders, commonly biting multiple people in quick succession, fueling the spread of the virus. They are most active during mid-morning and then again between late afternoon and nightfall. Scientists have found Zika can be transmitted sexually - from both men and women. Couples should abstain or wear condoms for eight weeks if either partner has traveled to a country with a Zika outbreak, regardless of whether they have symptoms. A mother can pass the virus to her unborn baby during pregnancy. There are two ways this can happen: through the placenta, and through the amniotic sac. Since the virus can live in the womb lining, there is a chance the baby can become infected during birth. The majority of people infected with Zika virus will not experience symptoms. Those that do, usually develop mild symptoms - fever, rash, joint pain, and red eyes - for no more than a week. There is no specific treatment for the virus and there is currently no vaccine. CAN THE SPREAD BE STOPPED? Individuals can protect themselves from mosquito bites by using insect repellents. They could also wear long sleeves and long pants - especially during daylight, when the mosquitoes tend to be most active, health officials say. Eliminating breeding spots and controlling mosquito populations can help prevent the spread of the virus.</s>Inspector Sharon Nagel drops larvicide granules into a drainage area as she helps the county fight to control the Zika virus, July 30, in Miami.

Joe Raedle / Getty Images</s>A drug currently used to treat tapeworms could beat the Zika virus, according to a groundbreaking new study.

In a series of experiments, researchers found the existing medication is highly effective at stopping the deadly virus from replicating in the body.

The discovery was made by a team of researchers from Florida State University (FSU), Johns Hopkins University and the National Institutes of Health.

It has been hailed as a medical breakthrough as federal regulators race to find treatment for the infection, which is spreading through the US.

Professor Hengli Tang, of FSU, said: 'We focused on compounds that have the shortest path to clinical use.

'This is a first step toward a therapeutic that can stop transmission of this disease.'

Profossor Tang and his colleagues identified two different groups of compounds that could potentially be used to treat Zika.

One stops the virus from replicating, and the other that stops the virus from killing foetal brain cells, also called neuroprogenitor cells.

One of the identified compounds is the basis for a drug called Niclosamide - an approved drug that showed no danger to pregnant women in animal studies.

It is currently available as a treatment for tapeworm.

Researchers said the drug could be prescribed by a doctor today, although further tests are still needed to determine a specific treatment regime for the infection.

Although the Zika virus was first discovered in 1947, little was known about how it worked and its potential health implications - especially among pregnant women - until last year's outbreak in South America.

The virus can cause abnormally small heads in unborn babies, known as microcephaly, leading them to be born with severe birth defects.

Professor Tang said: 'It's so dramatic and irreversible.

'The probability of Zika-induced microcephaly occurring doesn't appear to be that high, but when it does, the damage is horrible.'

Researchers around the world have been working to better understand the disease - which can be transmitted both by mosquito bite and through a sexual partner - and also to develop medical treatments.

Earlier this year, Professor Tang's team was the first to show that the Zika virus caused cellular phenotypes consistent with microcephaly.

They subsequently screened 6,000 compounds that were either already approved or were in the process of a clinical trial because they could be made more quickly available to people infected by Zika.

Professor Hongjun Song, of Johns Hopkins University, said: 'It takes years if not decades to develop a new drug.

'In this sort of global health emergency, we don't have time. So instead of using new drugs, we chose to screen existing drugs.

'In this way, we hope to create a therapy much more quickly.'

Now the researchers are continuing to work on the compounds and hope to begin testing the drugs on animals infected with Zika in the 'near future.'

The latest findings were published by the journal Nature Medicine.

The Zika (ZEE'-ka) virus was first discovered in monkey in Uganda in 1947 - its name comes from the Zika forest where it was first discovered. It is typically transmitted through bites from the Aedes species of mosquitoes. They are aggressive feeders, commonly biting multiple people in quick succession, fueling the spread of the virus. They are most active during mid-morning and then again between late afternoon and nightfall. Scientists have found Zika can be transmitted sexually - from both men and women. Couples should abstain or wear condoms for eight weeks if either partner has traveled to a country with a Zika outbreak, regardless of whether they have symptoms. A mother can pass the virus to her unborn baby during pregnancy. There are two ways this can happen: through the placenta, and through the amniotic sac. Since the virus can live in the womb lining, there is a chance the baby can become infected during birth. The majority of people infected with Zika virus will not experience symptoms. Those that do, usually develop mild symptoms - fever, rash, joint pain, and red eyes - for no more than a week. There is no specific treatment for the virus and there is currently no vaccine. CAN THE SPREAD BE STOPPED? Individuals can protect themselves from mosquito bites by using insect repellents. They could also wear long sleeves and long pants - especially during daylight, when the mosquitoes tend to be most active, health officials say. Eliminating breeding spots and controlling mosquito populations can help prevent the spread of the virus.</s>Washington, DC - Researchers at the National Center for Advancing Translational Sciences (NCATS) recently identified compounds that potentially can be used to inhibit Zika virus replication and reduce its ability to kill brain cells. These compounds now can be studied by the broader research community to help combat the Zika public health crisis. NCATS is part of the National Institutes of Health.

Using NCATS’ drug repurposing screening robots, researchers identified two classes of compounds effective against Zika: one is antiviral, and the other prevents Zika-related brain cell death. The compounds include emricasan, an investigational drug currently being evaluated in a clinical trial to reduce liver injury and fibrosis, and niclosamide, a U. S. Food and Drug Administration-approved drug for use in humans to treat worm infections. In addition, the researchers identified nine cyclin-dependent kinase (CDK) inhibitors. CDK usually is involved in regulation of cellular processes as well as normal brain development, but the Zika virus can negatively affect this process.

NCATS’ work was a collaborative effort with Johns Hopkins University, Baltimore, (JHU) and Florida State University, Tallahassee, (FSU), and the study results were published in the August 29 issue of Nature Medicine. The NCATS screening effort builds on the initial research by JHU and FSU scientists, who discovered that the Zika virus infects brain cells early in development. Infection by the Zika virus may be related to fetal microcephaly, an abnormally small head resulting from an underdeveloped and/or damaged brain.

The Zika virus has been reported in 60 countries and territories worldwide; currently, there are no vaccines or effective drug treatments. The virus is spread primarily through bites from infected Aedes aegypti mosquitoes, and in addition, can be transmitted from mother to child and through sexual contact. It also is associated with neurological diseases such as Guillain-Barré syndrome in infected adults.

“The Zika virus poses a global health threat,” said Anton Simeonov, Ph.D., NCATS scientific director. “While we await the development of effective vaccines, which can take a significant amount of time, our identification of repurposed small molecule compounds may accelerate the translational process of finding a potential therapy.”

NCATS researcher Wei Zheng, Ph.D., and his team led the drug repurposing screen to test three strains of Zika: Asian, African and Puerto Rican. The scientists first developed an assay (test) using caspase 3, a protein that causes brain cell death when infected by the virus. The next step was screening 6,000 FDA-approved and investigational compounds, which resulted in the identification of more than 100 promising compounds. The team then evaluated the protective effect of these compounds in brain cells after Zika virus infection. Three lead compounds, emiracsan, niclosamide and a CDK inhibitor known as PHA-690509, were identified as reducing neuronal cell death caused by Zika virus infection.

These compounds were effective either in inhibiting the replication of Zika or in preventing the virus from killing brain cells. For example, emricasan prevents cell death, and niclosamide and the nine CDK inhibitors stop the virus’ replication. The team also found that emricasan, when combined with one of the CDK inhibitors, prevented both cell death and virus replication. In addition, the team noted that the CDK inhibitors may be useful in treating non-pregnant patients who face an increased risk of Guillain-Barré syndrome and other conditions sparked by Zika infection.

The researchers cautioned, however, that the use of emricasan and niclosamide during pregnancy for Zika infection will need to be evaluated in pre-clinical toxicology studies and clinical trials.

“Using the NCATS drug repurposing platform for emerging infectious diseases can help rapidly identify potential treatments for urgent needs such as the Zika virus,” Zheng said. “While identifying promising compounds is a first step, our goal at NCATS is to facilitate the translation of these findings for evaluation in the clinic. The release of all the compound screening data in this publication and in the public PubChem database opens the door to the research community to do just that.”

NCATS’ screening effort enabled the broader research team to quickly translate their earlier discoveries toward work to develop treatments for Zika virus infection. JHU is working on a mouse model to study the neuroprotective effects of the compounds identified from the screen and studying the mechanism of action of the lead compounds. FSU is testing the efficacy of these compounds in a Zika virus mouse model and is also studying the mechanism of action of the lead compounds.

In addition to NCATS, FSU and JHU, the research was supported by Emory University, Atlanta; the Maryland Stem Cell Research Fund, Columbia; NIH’s National Institute of Neurological Disorders and Stroke through grants NS048271 and NS095348, NS047344 and NS097206; and NIH’s National Institute of Allergy and Infectious Diseases through grant AI119530.</s>WHO emergency panel on Zika to convene on Sept 1

GENEVA, Aug 30 (Reuters) - The World Health Organization (WHO) said on Tuesday that its Emergency Committee on Zika would meet on Thursday to review the outbreak's evolution and neurological birth defects linked to the mosquito-borne virus.

The panel of independent experts led by Dr. David Heymann, which last met on June 14, convenes every three months to assess progress in the fight against the disease and malformations including microcephaly, a birth defect marked by small head size that can lead to severe developmental problems in babies.

The Zika virus was detected in Brazil last year and has since spread across the Americas. Singapore on Monday confirmed 15 new cases of locally transmitted infections, taking the tally to 56 as authorities step up efforts to contain the outbreak. (Reporting by Stephanie Nebehay; Editing by Dominic Evans)
The number of Zika virus infected in Singapore rises above 40.