Ho Chi Minh city, Dec 13 : Nearly 150,000 students from 9th and 12th grades in Vietnam's southern Ho Chi Minh City (HCMC), the country's largest Covid-19 hotspot, returned to school on Monday after a long time of learning online due to pandemic restrictions. Students of such grades who test positive for Covid-19, live in high-risk areas and are not staying in the city at the moment, will continue to study online in accordance with guidelines of the city's health sector, Xinhua news agency cited the Vietnam News Agency as reporting. HCMC is home to 205 high schools, of which 176 would welcome 12th graders back. Meanwhile, as many as 224 secondary schools out of the total 286 in the southern city would open for 9th graders, Under a pilot programme, the city will hold in-person classes for 9th and 12th graders from Monday until December 25, before allowing more students to come back to school. Between late October and early December, the southern city finished inoculating more than 709,600 children aged 12-17 years, according to the municipal centre for disease control. HCMC is now Vietnam's largest Covid hotspot with nearly 488,000 infections and 18,750 deaths as of Sunday, as per the data from the country's Ministry of Health. /IANS