Aug 18 (Reuters) - Florida"s largest school district on Wednesday imposed a mask mandate in defiance of the state"s governor, the latest chapter in the coronavirus political battle in the southern United States where new infections are highest. At a day-long meeting that grew contentious at times, the Miami-Dade County School Board voted to require most of the district"s 360,000 students, as well as staff, to wear face coverings when classes begin on Monday. Governor Ron DeSantis previously placed a ban on local mask mandates. “While I am a very, very strong advocate, and always have been, for parental choice, what we are facing in our community is a public health emergency where lives are at risk,” said board chair Perla Tabares Hantman, who supported the mandate. The requirement, which the board approved by a 7-1 vote following the recommendation of its superintendent, exempts student who cannot wear masks for medical reasons. DeSantis last month signed an executive order barring local officials from imposing mask mandates. Like some other Republican governors, he has called mask-wearing a personal choice which for students should be made by parents. Miami-Dade joins at least two other counties that have bucked the governor"s order. The state Board of Education on Tuesday voted unanimously to punish Broward and Alachua counties for mandating masks in schools in defiance of the governor"s order, local media reported. They are the first to be punished, although no specific actions have been taken against them, the local media said. DAILY DEATHS TOP 1,000 As officials across the South spar over mask mandates, COVID-19 deaths in the United States reached a five-month high on Tuesday. More than 1,000 people were reported to have died on Tuesday, the most in one day since March, after the virus death toll spiked over the past month to a daily average of 769, according to a Reuters tally. read more In Tampa, Florida, nearly 5,600 students and over 300 employees of a single school district remained in isolation or quarantine on Wednesday after either catching COVID-19 or potentially being exposed to it. In Hillsborough County, which includes Tampa, the school board planned to hold an emergency meeting on Wednesday to determine the best way to mitigate the spread of the virus. Florida had the country"s third largest number of new coronavirus infections last week, while Texas, where Governor Greg Abbott has also been at odds with some local officials over masks, had the 12th, according to a Reuters tally. The top 10 states with most new cases were all in the South. Abbott, also a Republican, announced on Tuesday that he had tested positive for COVID-19, despite having been fully vaccinated, but had no symptoms of the illness. The school district in Paris, Texas, about 100 miles (160 km) northeast of Dallas, took a novel approach in its disagreement with the governor, making face masks part of the dress code for its nearly 4,000 students. "The Board believes the dress code can be used to mitigate communicable health issues, and therefore has amended the (Paris Independent School District) dress code to protect our students and employees," the board said in a statement on Tuesday. Reporting by Peter Szekely and Tyler Clifford in New York and Anurag Maan in Bangalore; Editing by Howard Goller Our Standards: The Thomson Reuters Trust Principles.