Shanghai will maintain its efforts to vaccinate the population and enhance measures in old neighborhoods where less than favorable living conditions pose greater challenges to COVID-19 epidemic control and prevention efforts, the municipal government said at a news briefing on Monday.

Over the past month, the city registered an increase in the number of residents aged 60 and above who have been vaccinated, said Zhao Dandan, deputy director of the Shanghai Health Commission. As of May 22, around 3.75 million residents aged 60 and above — or 64.71 percent of the population of this age group — in the city have received at least one dose of COVID-19 vaccines, Zhao said.

The number of people aged 60 and above who have received at least two doses has climbed to 3,612,000, up by around 12,000 from April 15. The number of those who have received their booster shots also increased to 2.28 million, up by more than 1 percent over the past month, according to statistics released by the commission.

"All districts shall optimize their vaccination services according to the local conditions and promote COVID-19 vaccination to elderly residents in a safe, standardized, and orderly manner," said Zhao.

Zhao pointed out that 163 vaccination clinics, or 40 percent of the city's total, have also resumed regular vaccination programs for children. Parents will need to make appointments on the Health Cloud app in advance before going to the vaccination sites.

Lin Jingjun, vice-governor of the downtown Huangpu district, said the district has 330 old residential neighborhoods that have communal kitchens and lack flush toilets. As such, the district government has taken various measures to enhance epidemic prevention and control efforts in these areas to achieve zero community transmission, Lin said.

The district government has dispatched mobile toilets to around 18,000 households without independent bathrooms and arranged timings for residents to dispose of human wastes so as to prevent gatherings.

Shanghai registered 55 confirmed COVID-19 cases and 503 asymptomatic infections on Sunday. All infections were found within quarantine and lockdown populations.