Chinese diners get meningitis from eating snails

As many as 50 people have been diagnosed with a form of meningitis after eating raw or half-cooked Amazonian snails in Beijing restaurants, and according to reports by the Chinese media five patients are in a serious condition at different hospitals in the capital.

The large, black snails are a popular dish in China and many people became ill after eating a snail dish called fushouluo at restaurants that specialize in Sichuan-style cooking.

According to Chinese researchers each Amazonian snail is host to 3,000 to 6,000 parasites, which can harm the human nervous system, leading to headaches, facial paralysis, meningitis and fever.

The first case in June was in a 34-year-old man who was taken ill after eating a dish of cold snail meat at Beijing's Shuguo Yanyi restaurant.

Tests which were then done on snails taken from the restaurant which found several infected with a meningitis-causing parasite called Angiostrongylus cantonensis.

Experts believe the actual number of affected patients might be higher than 50 but as it can take as long as a month for symptoms to appear the link between the illness and eating a raw snail may not be clear.

The same species of Amazonian snails is also being blamed for destroying large areas of farmland in the south of China where more than 160,000 hectares of crops have been destroyed in the Guangxi Zhuang region.

Amazonian snails originated in South America and were first introduced into China in the 1980s and they have since become widespread, breeding very rapidly and have now infiltrated lakes, brooks and ponds across the country.

Farmers in Guangxi have reported an invasion of Amazonian snails in their paddy fields which experts say have been encouraged by wet weather, brought by this summer's typhoons.

The Beijing Office of Food Safety has issued an urgent notice calling for tighter supervision over aquatic products and safety inspection in supermarkets, shopping malls and restaurants.

The office has also warned people against eating raw fish, shrimp, snail, crab, frogs and snakes, although those foods are not directly linked to the current meningitis outbreak.

In recent years China has been struggling to control a rise in the number of food-related health incidents; a major health scandal erupted in 2004 when China revealed that at least 13 babies had died from malnutrition in the country's impoverished eastern province of Anhui after being fed fake baby milk.

Several cases of bird flu in humans, which has infected 21 people, have been traced back to people eating sick birds.