Cleopatra sailing down the Nile kind of stuff.

Reality check: I am miserably, disgustingly ill. I have contracted norovirus, the virus spread by contact with contaminated food and water, which affects many hundreds, even thousands, of cruise passengers each year. The little blighter is so virulent, you can even contract it from contact with a surface touched hours before by someone with the virus. Or even by airborne particles.

It doesn't distinguish between classes of travellers. The only advantage of being on a 'luxury' cruise is that the toilet you spend so much time in is a marble one. When your nose is close to the tiles for 24 hours, I suppose it helps that they are clean and attractive. I think I made 30 visits to the bathroom in eight hours.

There is no cure for norovirus, nor much that can help, except for Imodium. You are very sick for one to three days. When I say sick, I mean projectile vomiting, diarrhoea, stomach cramps and low-grade fever. That's the sanitised version. It's so violent, you think you might die or have a heart attack (and dying may be preferable) but, if you're in reasonable health, you recover totally, except for the psychological scars of having spent the most degrading few days of your life.

I must say, I don't believe I contracted the norovirus on the ship. I blame the bathroom of a teahouse in a city we visited prior to the cruise and possibly a food handler in that cafe. It's hard to know, but the two companions with me in that place were also felled by it.

But equally, we might have contracted it from the fabric we handled in the market, or from a doorhandle we touched. The virus, which causes 21 million cases of illness a year, and is especially virulent in the northern hemisphere from November to March, survives hand-washing, dishwashing and laundering. Sufferers are contagious for a few days after recovery. Those alcohol-based hand sanitisers cruise ships provide may not kill it.

No wonder it's the bane of the cruise industry. In 2014, the mega ship, Explorer of the Seas, docked in New Jersey with 600 sick passengers on board. The same day, in a separate incident, the Caribbean Princess arrived in Houston carrying 192 sick people. There are frequent reports of outbreaks, even on ships such as Cunard's Queen Mary 2.

But it's not the ships that are sick. It's the passengers. Tens, maybe hundreds, of thousands of travellers by land come down with noro each year. It's not news when they are travelling solo or in small groups. But it is when 3000-6000 of them are confined in one space.

Most cruise lines have health and safety protocols in place that kick into hyper-drive when there's even one sick passenger on board. Some of the bigger ships even have equipment for testing specimens so that the virus is identified quickly and practices implemented to control its spread.

Ships may be taken out of commission and cleaned top to bottom if cases of noro occur on successive cruises. If you've had noro on a cruise ship, that's scant comfort, but the cruise industry wants you to know it's safe come onboard.

I don't think anyone can make any assurances. Wherever there are poor sanitary conditions and water in the world, there is risk for travellers.

I've been carrying a water-born parasitic infection, which I picked up in Sri Lanka, since November. I was therefore extra careful with hand-washing and I take special probiotics for the upper intestine; vitamins and also oregano oil, which supposedly is as effective as antibiotics in getting rid of certain parasites. I still came down hard with noro, as did my very fit companions. "Ravaged" is the word for it.

Right now, I'm feeling if I never see Southeast Asia again I'd be happy. But, of course, I'll get over this as soon as I'm better. I love the region and I've been other times when I haven't fallen ill.

Besides, it's not necessarily safer at home. The current strain of norovirus was first identified in Sydney a few years ago. Yes, it's called "Sydney 2012".