The World Health Organization will assemble an emergency committee to deal with what it says is a rapidly spreading Zika virus pandemic. However, scientists believe a vaccine is years away, while doctors say "questions abound" concerning the disease.

The UN-endorsed body says that since the first cases were registered in Brazil in May of last year, as many as 1.5 million people have been affected by the virus in that country alone, while more than 20 other Central and South American states have registered native infections as well. The disease had previously only broken out in small pockets of Africa and Asia.

"Last year the disease was detected in the Americas, where it is spreading explosively," Margaret Chan, the WHO's director general, said at a hastily arranged press briefing in Geneva. "The level of concern is high, as is the level of uncertainty. Questions abound - we need to get some answers quickly. For all these reasons, I have decided to convene an Emergency Committee."

Most people with the disease, a mosquito-borne cousin of dengue and yellow fever, do not know they have been infected, or suffer mild flu-like symptoms. However, a notable minority appear to develop Guillain-Barre syndrome, a severe auto-immune condition, or give birth to children with microcephaly, a birth defect that results in an underdeveloped head and brain.

"A causal relationship between Zika virus and birth malformations and neurological syndromes has not yet been established - this is an important point - but it is strongly suspected. The possible links have rapidly changed the risk profile of Zika from a mild threat to one of alarming proportions," said Chan.

Before 2015, Brazil experienced fewer than 200 cases of microcephaly a year, but that figure has exploded to about 4,000 since the Zika outbreak, though officials say many can be attributed directly to other causes.

A team of health workers has reached Itawa village in Kapilbastu district, where six children died of a yet-to-be-identified disease with symptoms similar to that of measles. The District Public Health Office, Kapilbastu dispatched the team to the village Ward Number 7 and 8 of the Somdiha VDC near the Nepal-India border.

The team is treating the infected children of the village. Team leader and officiating chief of the District Public Health Office, Bishnu Jayaswal said they were making home visits in the village and treating the infected children.

They were collecting blood samples simultaneously. He said the infected children had rashes like that of measles all over the body, high fever, and diarrhoea. They have also shown symptoms of malnutrition. The blood samples have been sent to the Central Health Laboratory at Teku, Kathmandu and the disease will be identified once the blood report is available. The unidentified disease has so far claimed the lives of six children in the village. All the victims are below five years. As many as 50 children have been infected, the District Helath Office stated.

Sierra Leone officials have confirmed a death from Ebola, hours after the World Health Organization declared the latest West Africa outbreak over.

The country was declared free of the virus on 7 November, and the region as a whole was cleared when Liberia was pronounced Ebola-free on Thursday.

Tests on a person who died in northern Sierra Leone proved positive, an Ebola test centre spokesman told the BBC. The WHO has warned, however, that more flare-ups are expected. The Sierra Leone death occurred earlier this week.

Ebola test centre spokesman Sidi Yahya Tunis told the BBC that the patient had died in the Tonkolili district. He had travelled there from Kambia, close to the border with Guinea.

The tests were conducted by British health experts. The BBC's Umaru Fofana in the capital Freetown said health officials were now urgently seeking those who had come into contact with the victim.

Close to 4,000 people have died of Ebola in Sierra Leone, and 11,000 people across the region, since December 2013.

Liberia was the last country to see the end of active transmission of Ebola. But it had been declared clear twice before, only for the infection to re-emerge.

International trade and travel has literally opened up new vistas for humans, ranging from travel to exotic places to enjoying the products and services of those distant lands. But along with international trade and travel comes the risk of spreading infectious diseases, a growing problem in today's global economy, says an Arizona State University researcher.

"The recent Ebola outbreak made us realize that we are all just a plane ride away from exposure to emerging infectious diseases," says Charles Perrings, an ASU professor of environmental economics. Perrings recently published the paper, "Options for Managing the Infectious Animal and Plant Disease Risks of International Trade," in the early online version of the journal Food Security.

The paper reported project results to an international conference "Global Plant Health Risks and Consequences: Linking Science, Economics and Policy," hosted by the British Food and Environment Research Agency, and supported by the Organisation for Economic Cooperation and Development's Cooperative Research Programme on Biological Resource Management for Sustainable Agricultural Systems. Perrings is the principle investigator of a project funded by the National Science Foundation-National Institutes of Health-U.S. Department of Agriculture Ecology and Evolution of Infectious Diseases program in collaboration with the UK's Biotechnology and Biological Sciences Research Council.

In the paper, Perrings describes the growth of international trade since the 1950s and the increasingly tight coupling of developed and developing economies. The paper considers how the global community currently deals with trade-related infectious disease risks of animals and plants, and asks how the system could be made more effective.

An example of the impact of an infectious disease came in 2001 in the UK when an outbreak of hoof and mouth disease cost some $10 billion and more than 2 million sheep and cattle had to be destroyed, Perrings said. More recently, African swine fever--a much more serious disease of pigs--has been spread in the Caucasus region through trade in pork, pork product or through waste in trade vehicles.

Nearly 200 people who attended a catered party at a downtown Seattle office building have become ill with norovirus, a public health official said on Monday.

Public health officials closed all the food-service locations inside the Russell Investments Center in downtown Seattle, including a Starbucks location, said Dr. Meagan Kay, a medical epidemiologist for the public health department.

Norovirus can spread by an infected person, contaminated food, water or contaminated surfaces, the CDC said. Nearly 200 people out of roughly 600 people who attended the party catered by California-based Bon Appetit Management Co on Tuesday reported some level of sickness, Kay said. That number is likely to go up as the investigation continues into the cause of the outbreak, she said.

"The source of this illness remains unclear, and we are as eager as anyone to learn precisely how and when it began," the catering company said. "We have worked with our food safety experts to disinfect the surfaces in our facility and have taken all other necessary steps to ensure food safety."

Two people have been hospitalized overnight and eight people visited an emergency room for their illness, though the conditions of the patients were not known, Kay said. Over the weekend, the building was disinfected in part to address vomiting in restrooms and to clean door knobs and other surfaces, Kay said.

The virus causes the stomach or intestines or both to become inflamed with acute gastroenteritis which leads to stomach pain, nausea and diarrhea, according to the Centers for Disease Control and Prevention. It is the most common cause of foodborne-disease outbreaks and acute gastroenteritis in the United States, causing some 19 million to 21 million illnesses and 570-800 deaths annually, the Centers for Disease Control and Prevention said.

A man who identified himself as Bryan said on a health department blog that he and his wife, who is eight months pregnant, had become sick. He said he had gone to the emergency room and received intravenous fluids.

Fisherman in northern Norway first noticed the strange-looking purple slime in late August of this year. At first, there were large clots of the slimy stuff, but now, it has collected in a 200 meter (219 yards) wide belt around Lyngen Fjord.

Whatever the purple slime is, it's freaking out fishermen and sailors alike, and no one seems to know what it is. There are various descriptions of the mass of purple slime, from clotted and mucoid, to gelatinous and gooey.

The Local, Norway's news in English reported that Roger Larsen, an associate professor at the University in Tromsø, told state news broadcaster NRK, "We have not been able to find out what this really is, other than that we are talking about large amounts of jellyfish."

Here's another reason to stay in New York this holiday season — the "kissing bug" has now spread to 28 states.

Texas is the latest to report an outbreak of infections from the Latin American triatomine bug after the pest had been spotted in other southern and western states, including Georgia, Alabama and California, according to the Centers for Disease Control and Prevention.

The creepy crawler resembling a cockroach gets its colorful nickname because it likes to bite around the lips and eyes of people when they are asleep. More than half of the bugs carry a parasite that can cause Chagas disease in humans, dogs and other mammals.

The good news? To actually pass on the disease, the bug not only needs to bite you, but then defecate into the gash. If left untreated, up to 30% of bite victims will develop chronic conditions such as difficulty breathing, heart and intestinal complications, and, in extreme cases, death.

There have been eight million cases in Latin America and South America because of poorly constructed rural homes, according to the CDC.

To prevent an outbreak, the CDC recommends:

Sealing cracks and gaps around windows, walls, roofs, and doors.

Removing wood, brush, and rock piles near your house.

A mysterious purple slime has emerged off the coast of northern Norway, coating millions of cubic meters of a picturesque fjord with a strange mucoid, margarine-like substance.

"We have not been able to find out what this really is, other than that we are talking about large amounts of jellyfish," Roger Larsen, associate professor at the University in Tromsø, told state news broadcaster NRK on Sunday.

"The images we are picking up from the echo sounders and other equipment are totally atypical.

We have tried to gather information to find the answers, but I am absolutely sure that this is something we've never seen before."

Larsen, who has been surveying the emergence of the slime since fishermen first began reporting it in late August, said that the substance had collected in a 200m wide belt around the Lyngen Fjord.

"We are talking about millions of cubic metres," he said.

Fast food chain Chipotle voluntarily closed 43 restaurants in Washington State and Oregon over the weekend after health authorities launched an investigation into 22 cases of E. coli poisoning. Beef shipped across the US has also been recalled.

"There have been links made to six restaurants in the Seattle and Portland areas," Chris Arnold, communications director for Chipotle, told The New York Times. "We have closed 43 restaurants in those markets out of an abundance of caution."

The company is not planning to close any other restaurants because there is no evidence of an E. coli link to other locations. Re-openings will depend on the investigation.

The Oregon Health Authority said in a statement over the weekend that the outbreak affected people who had eaten at Chipotle outlets from October 14 to 23. They expect the number of cases to rise as more people hear about the situation and seek medical attention.

Scientists have found a biomarker in the blood that can tell if a person is more likely than others to die early from pneumonia or sepsis.

The biomarker is associated with chronic inflammation, perhaps due to microbial infection, and predicts death from infection up to 14 years in the future, said researchers today in the journal Cell Systems.

But, the researchers warned further research was needed before a test for the biomarker would be warranted.

In the past year, scientists have found that when a collection of common proteins called GlycA is elevated in the blood, a person is more likely to die prematurely.

"Per unit increase of GlycA, you get an increased risk of death, from any cause, of between 40 and 50 per cent," said Dr Michael Inouye from the University of Melbourne's Centre for System Genomics. But little was known about the biology of the GlycA biomarker, and how it could lead to early death.

"We wanted to understand why, because without that you can't remove the risk," said Dr Inouye.

He and colleagues analysed data, much of it electronic records, on over 10,000 adults from Finland and found that those who had elevated GlycA tended to be more likely to die from sepsis and pneumonia.

"As GlycA increases, your risk of disease increase," Dr Inouye said.

"There were some strong associations. People who had one unit increase in GlycA levels were at 2.2 fold increased risk from sepsis, which makes up the majority of systemic infections."

Importantly, the study showed that when GlycA levels became elevated they tended to remain so for up to a decade, and GlycA predicted death from infection up to 14 years in the future.