KOBE, Japan (AP) _ Officials appealed for medicine Wednesday to combat a flu outbreak that threatened to turn into an epidemic in shelters that house hundreds of thousands of people who lost their homes in last week's earthquake.

The ground continued to rumble in Kobe, the western city that took the brunt of the Jan. 17 quake that killed more than 5,000 people. An aftershock of 4.7 set buildings swaying and sent new fears through a community wondering when its nightmare will end.

There were no reports of damage or casualties but high-speed trains in the area were halted and several expressways were closed as a precaution.

Eight days after the quake, about one-fifth of Kobe's population _ 307,000 people _ remained in tents and makeshift shelters set up in schools and government buildings.

Faced with the largest number of homeless people since World War II, Japanese officials fear the spread of any contagious disease, especially among the very old and the very young.

Provincial health official Michio Takaoka said 428 people in the shelters have been diagnosed with influenza in recent days. Another local official, Yasuhiro Kikkawa, said 154 doctors and 400 nurses, mostly volunteers, were trying to identify those at risk of serious illness.

``The doctors are very much concerned now about influenza,'' Kikkawa said. He said local authorities desperately needed more medicine and surgical masks to stanch the spread of disease.

As of Wednesday, the death toll from the quake stood at 5,074 with 61 missing and 26,618 injured. Nearly 75,000 buildings were damaged or destroyed.

In an effort to ease the general misery, Japanese troops erected several temporary public baths around the city, giving thousands of people their first opportunity to bathe since the quake.

``It was fantastic, very hot,'' exclaimed truck driver Fumio Tamai, 42, as he emerged with dripping hair and a broad grin from a makeshift bath at a city pier. ``I'm going to come here every day that it's open.''

Bathing is a prized ritual in Japan, and city officials said the earthquake left more than half of Kobe without running water. The first of the public baths opened late Tuesday, and more opened Wednesday.

Authorities condemned 1,268 quake-damaged buildings and began demolishing some of them with the help of Japanese troops. Officials are anxious to prevent more deaths and injuries from aftershocks.

Although conditions in this city are gradually improving, the upheaval has begun to fray Japan's social order. Police report 242 motorcycles were stolen in the seven days after the quake, slightly more than the total number taken during the entire month of January last year.

Strain was also evident at the gleaming new Kansai International Airport in Osaka Bay, where 1,000 quake victims have taken shelter. Airport officials said they were worried that passengers would object to the victims' presence.

Japan is only now beginning to reckon the cost of the quake on a society that thought its technological prowess could shield it against disaster.

The collapse of many supposedly earthquake-resistant roads and buildings has raised concerns over safety and brought new urgency to the task of upgrading standards of structures throughout this seismically active country.

In Tokyo, city officials announced plans to reinforce pillars along elevated highways in the capital as a protection against quakes. And Japan's science and technology agency will review quake-resistance standards for nuclear power plants, the Yomiuri newspaper reported Wednesday.

Shoichiro Toyoda, chairman of the Japan Federation of Economic Organizations and a leading industrialist, told reporters that Japan's recovery from its three-year recession ``may be delayed a bit'' by the earthquake.

Toyoda, who is also chairman of Toyota Motor Corp., predicted that rehabilitation costs would probably run higher than the $30 billion to $80 billion forecast by the government and private economists. But he offered no specific figure.

Japan has received offers of assistance from 55 countries, two United Nations organizations and the European Union. So far, only 15 offers have been accepted.

Government reluctance to accept foreign aid is causing resentment among many ordinary Japanese.

``There are many people in the center of politics and bureaucracy who may be capable of scoring high marks on exams but have no ability to make judgements,'' college lecturer Junko Murakami said in a letter to the Yomiuri newspaper.

``They should leave their government positions, because they have no ability to cope with disaster.''