It was around Christmas when Gary Coleby first suspected that a few of his coughing pupils were suffering from something more serious than a prolonged bout of the common cold. “There were two or three children in one tutor group who had been ill for some time,” he says. “I thought that they should be looked at.” He called the local health authority and their tests confirmed his worst fears. They had tuberculosis.

Mr Coleby is head of Crown Hills community college in Leicester, until then just another inner-city secondary striving to help its kids beat the anti-social odds with a decent education. Ofsted praised it last year as “one of the best urban schools in the country”. But, by the end of March, news that three of its pupils were infected with TB had hit the headlines, and normal school life was thrown into disarray.

Crown Hills rapidly became known as the school at the centre of the “TB outbreak”, as mass screenings of staff, pupils and parents revealed 62 cases. When further cases emerged at other schools in Leicester, Newport and Manchester, and news broke that a London nursery school teacher had collapsed with the disease, there was a frenzy of media speculation about inner city schools as fertile sites for a modern-day TB epidemic.

Not that Mr Coleby was particularly alarmed at first. “I’ve worked in quite a few schools,” he says. “And you do get cases periodically - almost every year in fact. So it wasn’t the discovery of TB that shocked me, so much as the attention it got and people’s reactions.”

Nevertheless, in an age when people read about the dreaded “consumption” only on the pages of a Dickens novel, TB appeared in the papers like the ghost of hard times past, evoking memories of the “great white plague” that once spread without cure or control through the crowded slums of rapidly expanding cities during the 18th and 19th centuries. Few reporters bothered to mention that it is now easily cured.

“Some of the media attention made it sound like our kids were falling down ill every day,” says Mr Coleby. “I suppose people harked back to the days when people died regularly from TB. But in those days people also died of chickenpox, measles and flu.”

Tuberculosis is caused by an air-borne germ, the bacterium tubercle bacillus, which usually attacks the lungs, making breathing difficult and leading to excessive coughing, fevers, fatigue, rapid weight loss, and blood in the phlegm (although it can infect other parts of the body too, such as glands, bones, sexual organs and brain). It is spread on microscopic droplets expelled from the lungs when an infected person coughs, sneezes, talks or spits.

Yet contrary to the headline warnings of an impending epidemic which followed the rash of cases at Crown Hills, TB is difficult to catch. Professor Francis Drobniewski, director of the TB centre at the Public Health Laboratory Service (PHLS) in London, explains. “You can’t suddenly become infected with TB in a short time; it’s not highly contagious in that way,” he says. “You have to spend several hours in the company of an infected person to be at risk, so it spreads slowly.

“Obviously, schools are institutions where people spend a lot of time together as a group,” he says. “So if a child or adult at school has TB, clearly there is a risk of the infection spreading.” However, children can’t easily catch the disease from other children; the greater risk is when an adult is ill, although even then children of school age - other than those from recognised high-risk groups (see box) - are at very low risk.

“It is most likely to spread in conditions of poverty and overcrowding,” says Professor Drobniewski, hence its association with the urban squalor and mass institutions of industrialising societies, whether 19th-century Britain or today’s rapidly urbanising developing world.

The earliest evidence of TB dates back to the Neolithic age, around 5000BC, and there are signs that it was common in ancient Egypt and Roman Britain, but the disease became rife only with the emergence of large, crowded cities. By the mid-17th century “consumption” - so-called because it appeared to take over the whole body - was responsible for one in five deaths in London. Sanitation and improved public health facilities meant the disease began to decline slowly in the first half of the 20th century - healthier bodies were better able to fight the bacteria. And, in 1882, Robert Koch discovered the TB bacterium and developed a skin test to detect infection. Between 1910 and 1920, Calmette and Guerin developed a weakened form of the bacteria, the Bacille Calmette-Guerin, or BCG, which could be injected to induce immunity.

Although never 100 per cent effective, BCG vaccination programmes became common from the 1930s onwards - a national programme was introduced in Britain in 1953 - and, with new antibiotic drugs developed in the 1940s and 1950s, helped to reduce TB dramatically after the Second World War.

But TB never disappeared. Although cases in England and Wales fell from 46,500 in 1953 to just over 5,000 in 1987, the rate of infection has been increasing again since the late 1980s, both in the West and in the developing world. In 1998, the World Health Organisation estimated that a third of the world’s population - nearly 2 billion people - were infected with the bacteria, and that 8 million new cases of the disease occurred each year, causing about 2 million deaths.

Today, someone is infected with TB every second, it is still the leading cause of death from a single organism, and kills more adults than Aids and malaria combined. In the UK, the number of cases has risen to nearly 7,000 per year, and there are about 400 deaths annually. In January, the PHLS released figures showing that the number of cases increased by more than 10 per cent last year over 1999, and by 34 per cent since 1987, declaring this “a cause for concern”. Forty per cent of UK cases are in London, and a growing proportion are found among communities with origins in “high incidence” regions such as sub-Saharan Africa (1.5 million cases per year) and South-east Asia (3 million per year).

However, while it’s true that greater migration worldwide is a factor in the recent re-emergence of TB, it certainly doesn’t justify the kind of “unacceptable” (racist) correspondence that landed on Mr Coleby’s desk at Crown Hills at the height of the crisis. Ninety per cent of the school’s intake is Asian, yet the source, or sources, of the Leicester outbreak have still not been found and there is no evidence to suggest it started in the local Asian community. Similarly, an 18-month suspension (which has now ended) of the national school BCG programme, caused by a vaccine shortage, is not seen as responsible for the recent spate of infections. Nearly all the infected pupils at Crown Hills had been vaccinated. What’s more, only four of the “positive cases” among staff and pupils needed hospital treatment, and all were back on their feet, and at school, within weeks.

“In the end, the whole episode has galvanised the school’s relations with the local community,” says Mr Coleby. “It knocked us sideways for a bit but we have come through it stronger.”

THE TRUTH ABOUT TB

Who is most at risk?

Anyone can catch TB, but some people are more at risk, especially those living in the same house as someone with the disease. People with weak immune systems have a greater chance of becoming ill. You can be infected with the bacteria for years without developing the disease because the body is strong enough to stop it growing. However, the inactive bacteria can remain alive and become active later when the immune system weakens. People with TB infection - as opposed to the disease - have no symptoms and can’t spread it to others, but it usually shows up on a positive skin test. Many of the positive cases at Crown Hills were children with TB infection, not the disease.

When should a teacher be concerned?

The disease develops slowly, taking several months to appear. The symptoms to look out for are:

* fever and night sweats;

* persistent coughing;

* fatigue;

* weight loss;

* blood in phlegm or spit.

“If a child’s illness goes on and on, and particularly if they have a cough for longer than three or four weeks, then they should be examined,” says Professor Drobniewski.

How is it prevented and treated?

BCG vaccination is offered to all children in secondary schools, and to younger children if there has been TB in the family or community. But, according to Professor Drobniewski, it is only 70 per cent efficient.

All close contacts of people with TB are automatically examined and, if infected, treated with chemoprophylaxis therapy - one or two drugs taken for a short period - to prevent the disease developing.

People with the TB disease are usually treated with a combination of four drugs. Treatment takes around six to nine months but patients cease to be infectious to others after two weeks. More than 95 per cent survive. Before modern drug therapies, TB sufferers were put in sanitariums; they had a 50:50 chance of surviving after five years.

Some strains of TB have become resistant to drugs. The worst of these are called MDR-TB (multi-drug resistant TB) and people who catch these strains have a 50 to 95 per cent chance of surviving. Despite what one national newspaper claimed, the strain found in Leicester was not drug-resistant.

What needs to be done?

According to Professor Drobniewski, the NHS needs more specialist TB nurses and doctors and better and faster diagnosis to reduce the opportunity for TB to spread before it is treated. The PHLS is seeking to improve its own national diagnosis service, which is available to all health authorities, at a cost.

Gary Coleby believes that all schools should receive a letter from their health authority informing them of the signs to look out for and what to do if TB is suspected.

For more information visit the Public Health Laboratory Service website special section on TB: www.phls.co.ukfactsTBindex.htm Also try: www.netdoctor.co.uk