(AP) -- China locked down a remote farming town after two people died and 10 more were sickened with pneumonic plague, a lung infection that can kill a human in 24 hours if left untreated.
Police set up checkpoints around Ziketan in northwestern Qinghai province, where townspeople reached by The Associated Press by phone Monday said the streets were largely deserted and most shops shut.
Authorities urged anyone who had visited the town of 10,000 people since mid-July and has developed a cough or fever to seek hospital treatment.
On Sunday, a 37-year-old man identified only as Danzin became the second reported fatality from the outbreak. He lived next door to the first, a 32-year-old herder. The 10 sickened, mostly relatives of the herder, were undergoing isolated treatment in hospital, the local health bureau said.
The World Health Organization office in China said it was in close contact with Chinese health authorities and that measures taken so far to treat and quarantine sickened people were appropriate. It did not comment on the move to seal off the town.
"This form of pneumonic plague is probably the least common but the most severe," said WHO's spokeswoman in China, Vivian Tan. "It has a very high fatality rate and generally spreads quite easily. So we're certainly concerned about the situation."
In Ziketan, authorities have said homes and shops should be disinfected, and residents should wear masks when they go out, said a food seller surnamed Han who runs a stall at the Crystal Alley Market. Around 80 percent of the town's shops were closed on Monday, Han said, and prices of disinfectants and some vegetables have already tripled.
"People are so scared. There are few people on the streets," Han said by telephone. "There are police guarding the quarantine center at the township hospital but not on the streets."
According to WHO, pneumonic plague is one of the deadliest infectious diseases, capable of killing humans within 24 hours of infection. It is spread through the air and can be passed from person to person through coughing.
The Web site of the U.S. Centers for Disease Control says people infected must be given antibiotics within 24 hours of first showing symptoms, while people who have had direct contact with those infected can protect themselves by taking antibiotics for seven days.
A woman who lives in Ziketan, who refused to give her name when reached by telephone, said county officials distributed flyers and made television and radio announcements on how to prevent infection. The woman said police checkpoints were set up in a 17-mile (28-kilometer) radius around Ziketan and residents were not allowed to leave.
The situation in Ziketan was stable, said an official surnamed Wang at the local disease control center, who added the measures taken were "scientific, orderly, effective and in accordance with the law."
Officials refused to give further details about the situation or say how the herder was first infected.
Pneumonic plague is caused by the same bacteria that occurs in bubonic plague - the Black Death that killed an estimated 25 million people in Europe during the Middle Ages. Bubonic plague is usually transmitted by flea bite and can be treated with antibiotics if diagnosed early.
A 2006 WHO report from an international meeting on plague cited a Chinese government disease expert as saying that most cases of the plague in China's northwest occur when hunters are contaminated while skinning infected animals. The expert said at the time that due to the region's remoteness, the disease killed more than half the infected people.
The report also said that since the 1990s, there was a rise in plague cases in humans - from fewer than 10 in the 1980s to nearly 100 cases in 1996 and 254 in 2000. Official statistics posted on the Health Ministry's Web site showed no cases of plague last year and the previous year.
In 2004, eight villagers in Qinghai died of plague, most of them infected after killing or eating wild marmots, which are relatives of gophers and prairie dogs. Marmots live in the grasslands of China's northwest and Mongolia, where villagers often hunt them for meat.
WHO spokeswoman Tan said China was no stranger to dealing with the plague.
"In cases like this, we encourage the authorities to identify cases, to investigate any suspicious symptoms among close contacts and to treat confirmed cases as soon as possible. So far, they have done exactly that," Tan said. "There have been sporadic cases reported around the country in the last few years so the authorities do have the experience to deal with this."
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