/ 6 April 2003

Race to beat the Sars bug

In a glass cabinet behind the sealed doors of a north London laboratory the virus that has caused global panic sits breeding in a dish.

Every aspect of this lab, down to the lightbulb fittings, has been designed to prevent escape of lethal germs. It is a ‘high containment’ facility, used to investigate dangerous pathogens such as anthrax.

This is the frontline in the battle to beat severe acute respiratory syndrome (Sars), the flu-like disease which has claimed dozens of lives after breaking out in countries across the world.

The Observer was granted exclusive access to the lab in Colindale where the British effort to unlock the puzzling viral code is underway. Dr Maria Zambon, an authority on flu viruses, is leading a 40-strong team of scientists charged by the World Health Organisation with cracking the genetic ‘footprint’.

‘It is like a detective game, only on an extraordinary international scale,’ she explained.

In a week which has seen the number of cases leap fivefold, her efforts could not be more crucial. Dark lines under her eyes attest to the fact that Zambon, mother of a young son, has spent the last three weeks analysing data and looking at samples late into the night. ‘We can’t predict how this will go. It’s an emerging infection and we don’t know where it’s heading. It could peter out completely, or it could amplify.’

The lab can only be entered through sealed doors. Security is so tight that the walls are coated with fibre-glass resin instead of paint. Air pressure is negative to prevent germs escaping.

The Sars samples lie in a sealed glass cabinet and scientists can only work on them by putting their hands into rubber gloves attached to the cabinet. There is no possibility of direct human contact.

Zambon believes her team may be only days from creating a diagnostic test for the syndrome — a breakthrough which would tell doctors in Hong Kong, China, Vietnam, Taiwan, Canada and elsewhere within hours whether patients have the virus.

There is evidence, she said, that two viruses may be involved in the syndrome, one part of the Corona family, another an aparamixovirus.

At midday every day for the past two weeks she and her team have gathered in a room to join an international teleconference of scientists from 10 labs to discuss the fight against the disease. With new cases emerging by the hour, the pressureto come up with a test and treatment grows day by day.

The round-the-clock efforts of the British scientists would be some small comfort to Benjamin Yang. When he took his temperature yesterday morning it was 39.3C, up a degree on the day before. ‘I was afraid because I had flu symptoms so my mother brought me here for a check-up,’ said the 18-year-old Singaporean in muffled tones from behind a green surgical mask. ‘Better safe than sorry.’

‘Here’ is a tented area out side the emergency department at Tan Tock Seng Hospital, which is handling all suspected and proven cases of Sars in Singapore. For the last week 200 people a day have been going through the same routine as Yang. ‘On Thursday 17 got admitted from the screening,’ said Dr Chia Sing Joo, head of general surgery.

Tests are done by taking temperatures and recent clinical and travel histories. Those considered potential cases are given chest X-rays and tests to measure white blood cells. ‘Generally in pneumonia, the white blood cell count is down,’ Joo said.

‘We are giving patients adequate fluid to make sure they don’t dehydrate. Many have lost their appetite or got nausea so we have to give nutritional supplements.’

Panadol is prescribed to bring down fever and more serious cases are given steroids and serums.

Loretta, a nurse on one of the wards for moderately infected people, said: ‘We have strict infection control measures. Every patient is isolated in separate rooms. They are not allowed visitors and their bathroom is attached to their room.’ They are not even allowed to telephone their families — medical staff convey all communications.

This continues for up to three weeks, depending on the progress. ‘We have very strict criteria for release,’ said Dr Lee Cheng Chuan, a consultant in infectious diseases at Tan Tock Seng. ‘They have to have had no fever for four days and no cough, so they won’t transmit the disease.’

Once discharged, patients have to stay at home for at least a week before returning to school or work.

Life is even tougher for those in intensive care, where all patients are on oxygen. ‘They’re critically ill so we don’t really talk to them,’ said Christine, an intensive care nurse. ‘They just lie there. If we do intubations or other invasive procedures we have to wear respirators and tight-fitting masks. Then we discard everything and wash our hands.’

Morale at the hospital initially suffered as staff had no idea what to expect. But Joo said spirits rose after the strict measures were adopted and it became apparent that the disease is only passed through human contact and not in the air. ‘No staff have come down with Sars,’ he said.

The same cannot be said for the general public. The neighbourhood around Tan Tock Seng Hospital is a virtual ghost town. ‘Kentucky Fried Chicken even refused to deliver to the hospital,’ said Sabrina, a nurse in the emergency department.

Back at the lab in north London the hunt goes on. When samples arrive, from both British and Asian patients, they are treated as hazardous material and opened inside special containers. Part of the sample is enticed to grow by being inoculated into a tissue culture. A small piece is also processed for molecular analysis to try to identify the pathogen by looking at its RNA (ribonucleic acid) and its DNA using an electron microscope.

Once a sample has been grown it has to be transferred to the high containment facility. Dr Robin Ghopal, who works closely with Zambon, said: ‘The principle behind this lab is that we handle the pathogen itself within these cabinets. The sample goes in there and it doesn’t come out until it has been inactivated or wrapped in multiple layers (of protective material) and then it will go to a freezer for storage.’

But how was it created in the first place? The disease came out of Guangdong Province in China, home of both high-tech industries and a rural community reliant on agriculture. At some stage the virus leapt the species barrier, possibly from pigs.

At first it seemed to be transmitted through people sneezing or breathing out the germs, but the cluster of cases at the Hotel Metropole in Hong Kong, and scores of people infected at a large apartment complex in the city’s Kowloon Bay, suggest another route.

Dr David Heymann, executive director of communicable diseases at the WHO, said: ‘It appears there is something in the environment which is serving as a vehicle to transfer the virus. We don’t believe this is the air. It is possibly an object that people are touching and getting infected from…maybe a sewage system or a water system.

‘It could even be such a thing as a door handle, where someone with Sars has coughed and left droplets containing the virus, and then the next person gets these droplets on their fingers, touches their eyes or mouth and becomes infected.’

There is nothing new about emerging diseases such as Sars. Every few years a new human agent comes along to perplex the scientists and colonise our bodies. Viruses have been around longer than man and are remarkably adept at crossing between species and taking advantage of our DNA. They survive best in communities where people co-exist with animals, and the reasons so many different flu strains come from China is that a largely peasant economy depends on ducks, birds, and fowl for its existence.

Sars may seem virulent but is not one of the worst. It kills around five percent of those it infects but these often have an underlying illness, such as diabetes, heart disease or a weakened immune system. But perhaps in an increasingly sophisticated and high-tech age, Sars should act as a warning that it is these primaeval pathogens which are capable of flooring us.

Back at Tan Tock Seng, Benjamin Yang has a new spring in his step after an hour’s nervous wait. ‘I’m feeling a lot better now,’ he said after being told he does not have Sars.

‘They said it was just some bacterial infection.’ – Guardian Unlimited Â