Shanghai, April 30 : Thousands of elderly people in the Chinese city of Shanghai have been hit hard by a Covid-19 lockdown that has now dragged on for five weeks. Since the outbreak began in early March, more than 500,000 people have tested positive for the virus, with 337 deaths, according to a BBC report. Nearly 10,000 of those people have been aged over 80, the report said. China's Covid rules demand that anyone who is infected, or a close contact, must be sent to a state-run quarantine centre. It is not uncommon for hundreds of people to be put together in such centres. Images shared on social media have showed unsanitary conditions, with clogged up toilets and overflowing rubbish bins, the BBC reported. One woman in Shanghai told the BBC that her 90-year-old grandmother who is in one such centre, is struggling with unsanitary conditions, unable to sleep properly, and has largely been left to fend for herself. She now fears her 91-year-old grandfather, who has also tested positive, will also be dragged to a centre, which she says will effectively be a death sentence, the report said. Her grandmother was the first to fall sick, the woman told the BBC. The lady tested positive on April 17 despite having never left the house since the outbreak began. In Shanghai's outbreak, nearly all victims have been elderly, unvaccinated residents with underlying health problems, according to Chinese officials. Only around 62 per cent of the elderly population are double vaccinated in the city, with around 38 per cent having received their booster shot. /IANS