SO strong is Shanghai's fetish for booze-bathed ''drunken prawns'' and other raw seafood that diners are ignoring a city-wide ban on the dishes and the risk of a possibly fatal illness. The official Youth Post said the public were ignoring the ban, imposed to head off a repeat of the ''hairy clam'' epidemic of the late 1980s when tens of thousands of residents contracted hepatitis from the local shellfish and many died. ''This newspaper advises the people of Shanghai - Stop eating raw seafood!'' the paper warned in a banner headline. ''Many of the 'drunken prawns', 'drunken crabs', 'drunken clams' and other uncooked seafoods that Shanghai people so love to eat carry disease-carrying bacteria . . . Some of the diseases they spread are life-threatening.'' Drunken prawns is one of many popular dishes in which live shellfish are brought to diners' tables, ''drowned'' in alcoholic spirits and quickly eaten - raw. Diners who mistakenly believe the alcohol can kill bacteria continue to pack restaurants serving the delicacies. City inspectors found that a staggering 95.5 per cent of such dishes tested at 32 restaurants had levels of intestinal bacteria beyond safe standards, the paper said. ''It doesn't matter what the Government bans, we've got anything and everything here,'' the paper quoted the manager of Lili Restaurant in Shanghai's free-market Gourmet Street. Officials blame the contamination on soaring pollution levels in the Huangpu River and East China Sea, much of it attributed to raw sewage from Shanghai. Although the Government has invested millions of yuan on cleaning up the environment, population growth along with a steady inflow of migrant workers into Shanghai are putting a heavy burden on the city's infrastructure facilities.