WARSAW, Oct. 18 (Xinhua) -- The construction of the first field hospital for COVID-19 patients was started at the National Stadium of Poland here in Warsaw, local media reported on Sunday evening.

The hospital, which will initially have 500 beds, is expected to be built within a week. The decision whether to build more similar hospitals in several provinces is to be made in the coming days, according to Polish Press Agency.

The Ministry of Health said on Sunday morning that Poland's number of confirmed COVID-19 cases has increased since Saturday by 8,536 to reach 175,766. Another 49 persons have died, bringing the death toll to 3,573.

On Saturday, Poland reported 9,622 new infections within 24 hours, the highest daily number in the country since the beginning of the epidemic.

As of Oct. 15, a total of 42 candidate vaccines were in clinical evaluation worldwide, including several from China, the United Kingdom, Russia, the United States, Belgium and Germany entering Phase 3 trial. Another 156 candidate vaccines were in preclinical evaluation, according to the World Health Organization.