A member of cabin crew was taken to hospital with "flu-like symptoms" today after falling ill on a British Airways flight from Mexico City to Heathrow.

The World Health Organisation has warned countries to be on alert for any unusual flu outbreaks after a swine flu virus was implicated in possibly dozens of human deaths in Mexico.

The BA employee, who has not been named, has been taken to Northwick Park hospital in Harrow, a hospital spokesman said.

He added: "He has flu-like symptoms and is responding well to treatment. The patient was admitted directly to a side room and the hospital is scrupulously following infection control procedures to ensure there is no risk to any other individual in the hospital."

The man was taken from flight BA242 which landed at 2pm today, a BA spokesman said.

Around midday Saturday, villagers were startled by an explosion and a fireball that many were convinced was an airplane crashing near their remote village, located in the high Andes department of Puno in the Desaguadero region, near the border with Bolivia.

Residents complained of headaches and vomiting brought on by a "strange odor," local health department official Jorge Lopez told Peruvian radio RPP.

Seven policemen who went to check on the reports also became ill and had to be given oxygen before being hospitalized, Lopez said.

Rescue teams and experts were dispatched to the scene, where the meteorite left a 100-foot-wide (30-meter-wide) and 20-foot-deep (six-meter-deep) crater, said local official Marco Limache.

At least 166 people have died and WHO says it is aware of 372 other cases.

Specialist laboratories in Gabon and Atlanta in the US confirmed Ebola from blood samples, saying they also showed the presence of Shigella dysentery.

Ebola is highly contagious. People contracting the disease suffer severe stomach pain and internal bleeding.

The fatality rate for Ebola, which has no known cure, is as high as 90%.

WHO and Medecins sans Frontieres have despatched medical personnel to help the Congolese contain the outbreak.

One of the major drivers is closer human contact with wildlife, primarily caused by human encroachment into, and modification of, wildlife habitat. For example, Ebola virus outbreaks often are linked to hunting for "bushmeat" or to mining development, and the AIDS pandemic originated from human encroachment into African forests for food.

The rise in international trade and travel is also important. The emergence of West Nile virus in North America, and AIDS and SARS globally, for example, arose from such travel and trade.

This globalisation of people and products is difficult to control and is largely related to increasing air transportation. With world air travel expected to grow at about 5% a year for at least the next 20 years, the problem of emerging infectious diseases will continue to grow, he warns.

The test result confirms that the lethal variant of the virus has arrived on the European continent.

"The results are that it is H5N1 but further laboratory results are required in order to confirm the origin of the virus," said a spokesman for the UK agriculture ministry.

Romanian officials have said further drastic measures will be needed to contain the outbreak.

Domestic poultry has already been culled in the affected area, and a 3km quarantine zone has been set up around it.

Results showing whether this case, or the earlier confirmed outbreak, is the lethal H5N1 strain found in Turkey are expected in the coming days.

The World Health Organization says there is a high probability that the first birds did carry that strain.

The news comes as EU veterinary officers hold an emergency meeting to discuss measures to contain bird flu.

In Turkey and Romania, the sites of bird flu infection have been close to areas favoured by migratory birds.

Working on virus samples from the remains of victims of the 1918 pandemic, the researchers were able to piece together the entire genetic sequence of the virus.

They found the virus contained elements that were new to humans of the time - making it highly virulent.

And analysis of the final three pieces of the virus' genetic code has revealed mutations that have striking similarities to those found in flu viruses found only in birds, such as the H5N1 strain currently found in south east Asia.

What exactly is bird flu?
Bird flu is a viral infection carried by wild birds. It has now spread to domesticated birds and has killed over 100 million of them. Now the bird flu virus has shown it can easily mutate and in some instances make a direct jump from birds to people. Thee have been at least 100 human cases mainly in the far east with the most case occurring in Vietnam.

When did the first human case occur?
1997

Why is bird flu different from regular flu?
Bird flu is genetically different and much more lethal with over half the victims dying. The most deadly type of bird flu virus is H5N1 and it is very similar genetically to the 1918 Spanish Flu that killed 59 million worldwide.

Dr Nabarro stressed he would be working hard to control bird flu through contact with farming communities and markets where birds are sold and looking at the migration of wild birds.

He said the number of deaths from any future influenza pandemic would depend on where it started, how quickly it was discovered and the kind of response they got from governments.

"The range of deaths could be anything between 5m and 150m," said Dr Nabarro.

"I believe that the work we're doing over the next few months will make the difference between, for example, whether the next pandemic leads us in the direction of 150 or in the direction of five. "So our effectiveness will be directly measured in lives saved and the consequences for the world."

In Israel, scientists have created the world's smallest computer by engineering DNA to carry out mathematical functions.

J. Craig Venter, the entrepreneurial scientist who mapped the human genome, announced last month that he intends to string together genes to create from scratch novel organisms that can produce alternative fuels such as hydrogen and ethanol.

With a $42.6 million grant that originated at the Bill and Melinda Gates Foundation, Berkeley researchers are creating a new malaria drug by removing genetic material of the E. coli bacterium and replacing it with genes from wormwood and yeast.

For example, national security experts and even synthetic biologists themselves fret that rogue scientists or "biohackers'' could create new biological weapons -- like deadly viruses that lack natural foes. They also worry about innocent mistakes -- organisms that could potentially create havoc if allowed to reproduce outside the lab.

The scare was triggered a few weeks ago when several research groups visiting Vietnam filed preliminary reports that many people with mild cases of influenza - and those in contact with them - were testing positive for the deadly avian flu strain H5N1. This suggested that there was widespread human-to-human transmission of the virus.

Subsequent tests have so far failed to confirm this, and WHO spokesman Dick Thompson is keen to play down the incident. "It was just unpublished information provided to us in preliminary form that spurred an investigation," he says. "We thought about upgrading the alert. We looked at it fast and strongly, and based on that decided not to upgrade."

A farm worker in South Sulawesi has tested positive for the H5N1 strain of the virus, although he has shown no outward symptoms of the disease.

In the past 18 months at least 53 people across Asia are known to have died of bird flu - all of them in Cambodia, Vietnam or Thailand.

The epidemic in Angola, thought to have begun weeks or months before it was recognized, is the largest on record. As of yesterday, there was a total of 376 suspected or confirmed cases in Uíge, including 315 deaths. The disease is spread by contact with body fluids like blood, saliva or urine, though people do not transmit the virus until they become ill. Those who recover can still transmit the virus sexually for about three months.

Ms. Bhatiasevi said that because the virus had also been found in breast milk, infected mothers were being advised not to breast-feed. Healthy mothers of infected children were also being advised not to breast-feed, she said, lest the mothers become infected as well.

Marburg, a close relative of the Ebola virus, causes a hemorrhagic fever that is often fatal within a week. The incubation period is three to nine days. There is no cure, and no vaccine.

"The results (of laboratory tests) came in yesterday ... It is indeed a case of Ebola," said Adamou Yada, WHO's representative in Congo, which has faced serious outbreaks of the disease in the past. Nearly 150 people died in 2003.

"Since the beginning (of the outbreak), we have registered 11 cases, including 9 deaths," Yada said in the capital Brazzaville. The latest outbreak is in the forested Cuvette-Ouest region, near the border with Gabon, where the 2003 outbreak struck.

As of 3 May, the Ministry of Health in Angola has reported 308 cases of Marburg haemorrhagic fever. Of these cases, 277 were fatal. In Uige Province, which remains the epicentre of the outbreak, 297 cases, of which 266 have been fatal, were reported. The large increase in the number of reported cases for Uige is the result of retrospective investigation and entry into the database of cases that occurred previously. However, new confirmed cases and deaths continue to be reported in Uige.

As a geographical reminder, while the viral hemorrhagic fevers such as Ebola, Lassa & Marburg have not been reported from Angola, Lassa fever is endemic in West Africa to the north of Angola, Ebola has recurrently appeared in the Democratic Republic of the Congo and the Republic of the Congo to the north of Angola, and Marburg was reported in backpackers travelling through Zimbabwe to the southeast of Angola.