Anthrax - facts and fiction

As fear of the disease sweeps across the world, ANDREW LAXON reports on the real and imagined dangers.

At the London stock exchange, 13 workers are taken to hospital for tests after a suspicious parcel arrives. An Israeli newspaper gets a letter with white powder and a note saying "regards from Afghanistan" and firemen in spacesuits sweep a suspicious substance from public gardens in Cyprus.

In New Zealand, anthrax letter scares in Taranaki and South Auckland put emergency services on alert.

These scares were all false alarms or hoaxes. London police found nothing in the parcel, the Israeli newspaper's letter was a prank by a rival tabloid and the Cypriot firemen discovered flour markings left by a running club.

The United States has had hoaxes too. But at least three anthrax letters in Florida, New York and Nevada were genuine and one person has died.

So how seriously should we take the worldwide anthrax alert? This is what we know so far.

What is anthrax?

The disease comes from a bacterium the size of a speck of dust. In its natural form it is found in spores (reproductive cells of plants and micro-organisms) in soil, but it can be mixed with other ingredients to form a more dangerous powder or liquid.

Until scientists began experimenting with its use as a biological weapon it was best known as a disease affecting farm animals.

The last human outbreaks in New Zealand are thought to have occurred about 100 years ago. The last cattle outbreak was in Te Awamutu in 1954, when 23 animals died.

How does it spread?

Anthrax cannot spread from one person to another. Humans can be infected by three strains - inhalational (by breathing it in), intestinal (by eating contaminated meat) and cutaneous (usually through a cut on the skin).

Inhalational anthrax, the strain most likely to be used by terrorists, leads to death in about 90 per cent of cases. Symptoms of fever and fatigue usually appear within a week of exposure.

Intestinal anthrax produces initial signs of nausea, loss of appetite, vomiting and fever, followed by abdominal pain, vomiting of blood, and severe diarrhoea. It is fatal in up to 60 per cent of cases.

About 95 per cent of anthrax cases are cutaneous. They usually occur when people are handling contaminated wool, hides, leather or hair products, especially goat hair of infected animals. The infection starts as a raised, itchy bump like an insect bite, but develops into an ulcer.

Untreated infections cause death in 20 per cent of cases but it can be easily detected and treated with antibiotics.

What is the best protection?

Most naturally occurring forms of anthrax can be treated with penicillin. But genetically engineered forms could be resistant to penicillin, so doctors usually treat patients with the stronger drugs doxycycline or ciprofloxacin, known as Cipro.

As the only Government-approved antibiotic for anthrax in the United States, Cipro has risen overnight from medical obscurity to wonder-drug, outselling Viagra on many online prescription services. The US Government has enough Cipro to treat two million people for 60 days, but the Bush Administration is to ask Congress for money to increase stockpiles to treat 12 million. Its manufacturer, Bayer, says it will increase production to 200 million tablets within three months.

The US embassy in Wellington has a three-day supply for staff.

Is there a vaccine?

There is, but it is limited to the US military and other people judged to be at risk. It requires several booster shots for full immunity and may not work against inhaled anthrax.

Researchers said yesterday they may have found a way to make an all-purpose vaccine by combining DNA from anthrax and other microbes, but it is some way off.

Is there any other way to guard against terrorists sending anthrax in the mail?

If you are really worried, iron your letters before opening them. Ken Alibek, a former Soviet germ-warfare scientist who is now a US-based author and researcher trying to develop defences against bioterrorism, told a congressional briefing yesterday that a hot, moist steam iron and moist fabric could kill anthrax spores.

For large amounts of mail, in big cities or postal distribution centres, he recommended portable gamma radiation units to sterilise letters.

How would terrorists get anthrax?

To make weapons-grade anthrax, a terrorist would need to grow the bacteria in a fermenter, spin or freeze the resulting slurry dry, spray the anthrax particles through a vacuum and then grind them to a fine powder - all possible, but requiring expert knowledge.

Anthrax is also believed to be held by nations suspected of running germ-warfare programmes, including Iraq, Iran, Libya and Syria. The old Soviet Union produced hundreds of tonnes of anthrax but Russia claims it no longer does.

How many people have been killed by these letters?

In the United States, one person has died, three others have been infected and 13 have been exposed to anthrax. Robert Stevens, 63, a picture editor for the Sun tabloid newspaper in Florida, died on October 5. His colleagues said he handled a letter addressed to actress Jennifer Lopez which contained a bluish powder and was being passed around the office. A mailroom worker in the same building, 73-year-old Ernesto Blanco, probably has also inhaled anthrax.

The seven-month-old son of an ABC television news producer contracted skin anthrax at a party at the station's New York headquarters but is recovering.

NBC news employee Erin O'Connor, who opened a letter addressed to newsreader Tom Brokaw, also developed skin anthrax.

The office of US Senate majority leader Tom Daschle received a letter with the same date and postmark. None of his staff have shown signs of exposure.

In Reno, Nevada, anthrax bacteria were discovered in mail at a Microsoft office but no staff were infected.

Is the worldwide fear out of proportion to the threat?

It seems to be outside the US, where there have been dozens of false alarms. But even in America, where the threat is genuine, hoaxers are having a field day. The FBI has received reports of more than 2300 incidents involving anthrax or other dangerous agents.

Two people have been arrested for sending hoax anthrax letters, the disruption caused by a false alarm has cost one state government office in Connecticut $US1.5 million ($3.6 million) and anti-virus watchdogs have discovered a computer worm, which claims to offer advice on anthrax side-effects.

Many false alarms are not malicious. Americans are taking literally the advice about suspicious mail given by Attorney General John Ashcroft: "Do not open it, do not shake it, leave the area and call local law enforcement."

Some commentators believe the Bush Administration has raised public anxiety to unrealistic levels.

"People need to realise that this is primarily a form of psychological warfare," said Jonathan Tucker, a biological and chemical weapons expert with the Monterey Institute of International Studies.

"I think the Government should try to counteract it with its own form of psychological reassurance."

Are the terrorists who attacked New York and Washington behind the anthrax letters?

The FBI says it has found no direct link with "organised terrorism" but cannot rule out the possibility. One theory is that many of the letters are from mentally unstable Americans looking for their 15 minutes of fame.

Full coverage: Terror in America

Pictures: Day 1 | Day 2 | Brooklyn Bridge live webcam