BEIJING , China ( CNN ) -- Travelers to China who display flu-like symptoms may be randomly quarantined over concerns of the swine flu virus , the U.S. State Department warned . A child traveling with his parents wears a face mask after they arrive at the Beijing , China , airport . There have been cases of children being separated from parents after either tested positive for the virus , also known as H1N1 , a travel alert said Friday . Chinese officials may give medications to minors in such cases without consulting their parents , according to the alert . `` Although the proportion of arriving Americans being quarantined remains low , the random nature of the selection process increases the uncertainty surrounding travel to China , '' the alert said . Swine flu is a respiratory disease of pigs transmitted to humans and caused by type A influenza virus . Symptoms include fever , lethargy , lack of appetite and coughing . There have been about 48,000 confirmed cases worldwide , including 519 in China , according to the World Health Organization . The Chinese government has taken measures to stop the spread of the virus . They include placing passengers who have fever or flu-like symptoms on a seven-day quarantine , the alert said . Others facing quarantine include those sitting close to travelers with symptoms , those with elevated temperatures and those from areas where virus outbreaks have occurred . A 15-year-old from Topeka , Kansas , told CNN on Monday that she was quarantined in Beijing for a week . `` Apparently , I was sitting too close to a man who had a fever on the 14-hour plane ride , '' Kaitlin Hannigan said , adding that she initially thought she had a fever , but her temperature was fine when officials checked it . A day after she arrived in Beijing with an educational group , government officials showed up at her hotel . `` They were wearing quarantine suits , goggles and masks and , like , full body suits and gloves , and said I had to be quarantined for seven days because I came in contact with that guy , '' Hannigan said . Earlier in June , New Orleans , Louisiana , Mayor Ray Nagin was quarantined in Shanghai after possible exposure to the virus . Nagin was headed to Australia on an economic development trip when he was quarantined for four days after sitting beside a passenger who was being treated for suspected swine flu symptoms . Nagin showed no signs of illness . State officials warned Americans traveling to China that they have to follow local quarantines procedures . `` The U.S. Embassy will be unable to influence the duration of stay in quarantine for affected travelers , '' the statement said . The travel alert expires in September .
Travelers to China with flu-like symptoms could face 7-day quarantine . Chinese government officials try to control spread of H1N1 virus . The U.S. Centers for Disease Control and Prevention says the swine flu is a "severe acute respiratory syndrome" that can cause coughing, fever, nausea or vomiting in some people who have not been immunized.