Severe Acute Respiratory Syndrome, or Sars, is causing panic around the world, having killed more than 80 people and infected thousands. China has come under widespread fire for its handling of the disease, which seems to have originated in Guangdong province.
By Holly Williams
BBC correspondent in Beijing
As I boarded the plane for Guangzhou, I noticed that I was the only passenger wearing a protective face mask.
The first case in Guangdong occurred in November 2002
My fellow travellers, all Chinese, aimed curious looks in my direction.
"'Why is that foreigner wearing a mask?" I overheard one man say to his girlfriend.
The Chinese have a saying that goes: "The mountains are high, and the emperor is far away".
Things that happen at one end of the vast Chinese empire, sometimes do not reverberate at the other.
As I flew over 1,000 miles to Guangzhou to investigate the mounting death toll there, the Chinese Government was still enforcing a near media blackout, and most people in Beijing still hadn't heard about the Sars outbreak.
But though China's state-controlled media may keep the public in the dark, thanks to modern technology, in some ways China is getting smaller.
Flights like the one I was on were already spreading Sars all over the country.
For many Westerners, the Chinese Government's decision not to tell its own public about this potentially fatal disease is shockingly irresponsible.
But I had been down this path before, and knew that Chinese bureaucrats would argue exactly the opposite.
The Chinese regime sees disease as a state security issue.
Tell the public that they're in danger and they might panic, goes the argument.
It is much better to let a few people die, but maintain public stability.
For years now, I have watched HIV/Aids handled in the same way.
Despite a looming Aids epidemic in central China, the majority of people simply don't know how to protect themselves against HIV.
In Guangzhou, though, I found that the government's paternalistic approach hadn't worked, and was actually spreading panic.
I met Mr Zhao, an old friend, at the airport.
He took me home to see his wife, and newborn baby daughter.
No one has told us what we should be doing to prevent the disease
"They're not leaving the house," he told me. "They are too worried about this disease."
As we drove along, though, everything seemed normal.
The streets were lined with hawkers and bargaining shoppers, honking traffic stampeded its way through narrow alleyways.
Guangzhou is the modern name for Canton - for centuries the commercial heart of China's South, famous for its free-wheeling capitalism.
"We have to keep on making a living, we have no choice," explained Mr Zhao. "But people here are very worried".
In their broom-cupboard of an apartment, we found Mr Zhao's wife, Pingping, boiling vinegar in her wok.
"It kills the virus," she explained, and showed me a cupboard full of traditional Chinese anti-flu medicine.
"Does it actually work?" I asked. "We are not sure," admitted Mr Zhao. "But what else can we do? No one has told us what we should be doing to prevent the disease."
The Zhaos first heard about Sars via a text message from a friend.
Then when Pingping went to buy vegetables in the market she found her acquaintances abuzz with news of sick friends, and rumoured deaths.
She went to the hospital to try to buy some medicine for her baby, and saw doctors and nurses wearing face masks.
Like many other people, the Zhaos became very frightened.
The Chinese health minister broke his silence on 3 April
"The price of vinegar multiplied by 50 overnight," explained Pingping.
"Everyone was boiling it at home, because no one knew what else we could do."
But still there was no word from the government.
Finally, after several weeks, a local television station announced that the disease was under control, and that people shouldn't worry.
"But we heard that more people were dying, and we still weren't sure what the symptoms were. We are very angry," Pingping told me.
But Chinese people aren't allowed to express anger with their government, and so most people adopt a fatalistic attitude to life and to death.
Leaving Pingping boiling her vinegar, Mr Zhao and I went off to the traditional medicine market.
We wove our way through piles of cane baskets filled with wild herbs and insect carcasses - the drugs that Chinese people have relied on for thousands of years.
I am worried for myself, and even more worried for my Chinese friends
Doctor Xia, an elderly and bearded practitioner, sighed deeply when I asked him if he was worried about catching Sars.
"It can be deadly," said the doctor, "but it is not really that big a problem. Only a few dozen people have died".
"But aren't you angry with the government for not giving more information?" I asked.
"Oh no, not really," he answered, smiling thinly. "That is just how things are here".
Other people I spoke to did not even want to talk to a foreigner about Sars.
As far as they were concerned, the government's media blackout meant that the disease was now a taboo subject.
But in Beijing, changes were afoot.
'Our country is safe'
Back in the capital the next day, I switched on the TV to find that the Chinese Government had apparently decided to come clean about Sars.
Finally, four months after the outbreak began, the health minister was being interviewed on the national news.
But China had not developed a free press overnight, and the message was predictable.
"The epidemic is under control," promised the minister. "People shouldn't worry."
"Our country is safe," he went on to say, directly contradicting World Health Organization warnings.
A few days later and I'm still waiting out the Sars 10-day incubation period, hoping I didn't catch it while in Guangdong - and that I won't contract it in Beijing.
I am worried for myself, and even more worried for my Chinese friends.
The government here has decided to put state control before the health of its own citizens.
Lucky for the authorities, people here seem resigned to putting up with it.
Even people who are angry, like the Zhaos, locking themselves inside with their four-month-old daughter, don't have a channel to communicate their frustration.
All they can do is listen to the comforting background buzz of China's government-controlled media.