A baby in Chinas epidemic-hit Wuhan city has been diagnosed with the novel coronavirus just 30 hours after being born, Chinese state media reported Wednesday. The infant is the youngest person recorded as being infected by the virus, which has killed nearly 500 people since emerging late last year. CCTV quoted experts as saying it may be a case of "vertical transmission", referring to infections passed from mother to child during pregnancy, childbirth or immediately after. The mother had tested positive for the virus before she gave birth. The official Xinhua news agency reported Monday that a baby born last week to an infected mother had tested negative. -Quarantine struggles- Health authorities are scrambling to halt the spread of a new virus that has killed hundreds in China, restricting visitors from the country and confining thousands on cruise ships for extensive screening after some passengers tested positive. But with important details about the illness and how it spreads still unknown, officials and medical personnel are struggling. Governments have rushed to get their citizens out of China, which is orchestrating history´s largest anti-viral campaign by blocking 50 million people from leaving Wuhan, the center of the outbreak, and nearby areas. A growing number of Chinese cities are discouraging people from even leaving their apartments. Villages have blocked entry points with piles of dirt and rubble, while businesses and offices remain closed indefinitely. As Beijing´s leadership faces questions over having kept its citizens in the dark for weeks before infections started to explode, other countries are trying to set up effective quarantines to stop a possible pandemic. Those efforts have not always been smooth, with violent protests near quarantine centers, banishment to remote islands, and some citizens allowed to leave quarantine early. The disease is believed to have emerged in December in a Wuhan market that sold wild animals and spread rapidly as people traveled for the Lunar New Year holiday in January. Chinas national health commission said on Tuesday that the oldest person diagnosed with the virus is a 90-year-old, and that 80 percent of reported deaths have been of patients 60 years of age and older.