Government plans to double the stockpile of antiflu drugs such as Tamiflu have raised concerns about a medical emergency and what could happen if the H5N1 strain of avian flu jumped to humans on a big scale. But should we be more concerned about the spread of drug-resistant tuberculosis? Or the threat of terrorist attack?

What we want to know is how real these dangers are and what we can do about them. Is it possible to distinguish between threats that quickly subside (remember the panic in Asia over Sars?) and ones that should concern us?

Answers to some of these questions, along with balanced advice, are available online. There is information that will help you evaluate the risks and put your mind at rest. There is also good advice about what to do should the worst happen.

EMERGENCY RESOURCES

For practical advice on how to act during an emergency, head to the government-run www.preparingforemergencies.gov.uk . Here you will find a rundown of possible emergencies, from severe weather to outbreaks of foot and mouth disease, with first-aid advice and a list of things to do if you are affected. It’s crucial, for instance, to know how to turn off the water, gas and electricity in your home should you be forced to evacuate. The site also lists emergency contact numbers.

The US Federal Emergency Management Agency site ( www.fema.gov ) is jazzier to look at, and particularly good on guidance for the aftermath of natural disasters such as floods.

BIRD FLU

You can follow the latest news and see a map charting the spread of the virus on the BBC website (tinyurl.com/e3jqw ). For facts and advice from big players such as the World Health Organisation, try www.fluwikie.com , which is a Wikipedia-style site devoted to helping people prepare for and perhaps cope with a possible pandemic.

The American health resource www.webmd.com says face masks offer little help in stopping you catching flu. Instead it advises that general hygiene rules, such as frequently washing your hands with an alcohol-based cleaner, are likely to be more effective.

Our own health department’s website (tinyurl.com/2kocqz ) advises that people can travel to countries with reported outbreaks of H5N1 but should avoid close contact with live or dead poultry.

David Nabarro, the senior bird flu expert at the United Nations, warns of between 5m and 150m deaths from a mass outbreak, and it is hard to be more precise. What we can say, is that any such outbreak is likely to cause widespread panic. However, Dr Marc Siegel’s article at tinyurl.com/adjys should allay some of those fears.

WAR AND TERRORISM

The fear of a nuclear attack has receded in most people’s minds since the end of the cold war. But some experts believe the threat is increasing because of the spread of nuclear know-how and weapons grade materials, which could allow rogue states and terrorists to get hold of dangerous weapons.

People fear a dirty bomb (a device constructed to spread radioactive nuclear material using conventional explosives) could contaminate a city centre for years and displace hundreds of thousands or even millions of people. In fact the excellent www.howstuffworks.com explains that long-term health and environmental effects would probably be minimal and that the real danger would be mass public panic.

The guide at eHow to spotting a terrorist (tinyurl.com/2wxhsm ) reckons, rather recklessly, that you can distinguish them by the baggy clothing worn in crowded places. But the best source for general terrorism information is www.terrorismanswers.org , which has pieces about terrorists, targets, weapons, financing and terrorism’s effect on the economy.

Like its advice on natural disasters, www.preparingforemergencies.gov.uk is also good on the basics of readying yourself for an attack that disables public infrastructure, causing, for example, power cuts. It recommends a list of essential items for the home, including bottled water, tinned food and a wind-up radio. You can buy masks that might protect you from smallpox, anthrax and the like, and body armour at www.surviveall.co.uk .

CLIMATE CHANGE

Wikipedia gives a terrific overview of the vast volume of climate change possibilities, threats and scenarios at en.wikipedia.org/wiki/Climate_ change . These include rising sea levels leading to floods, widespread drought and the “turning off” of the gulf stream, the warm current that flows along the coast of the eastern US to northern Europe, which would lower UK temperatures.

However, the reality is that nobody knows what might happen, or indeed what the timeframe will be. It’s even now debated what the biggest causes of global warming are. Methane is a greenhouse gas 20 times more powerful at driving global warming than carbon dioxide, and each day each of Britain’s 10m cows pumps out an estimated 100-200 litres of the gas. Better to give up meat than your 4x4.

A more immediate risk is that of flooding. The Environment Agency site (www.environment-agency.gov.uk/subjects/flood ) says about 5m people, in 2m properties, live in flood risk areas in England and Wales. You can tap in your postcode to see if you’re one of them. And as a last resort, Flood Ark sells barriers to protect you from minor flooding (www.floodark.co.uk ).

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