13 Hanoi students suspected to have H1N1 bird flu   A worker injects a chicken with bird flu vaccine at a farm in Suining, Sichuan province, China, February 26, 2008.Reuters/Stringer/Files Among more than 20 students in Hanoi who were hospitalized after developing avian flu symptoms, 13 are suspected to have contracted the H1N1 virus. Meanwhile, the Health Ministry has called for efforts to prevent H7N9 spreading from China into Vietnam.  All of these students, of Tri Duc High School, developed a fever, cough and respiratory problems when they were taken to hospital over the past few days, the Central Tropical Disease Hospital reported. Samples of the 13 patients have been taken for testing and two have been confirmed to have contracted the H1N1 virus, according to initial results of the tests, doctors said. Tran Dac Phu, head of the Health Ministry’s Preventive Health Department, said that the results of the remaining tests may be available today, January 22. “Weather in winter-spring is favorable for rapid avian flu outbreaks that can lead to an epidemic, especially in closed and crowded places such as offices, schools, and public locations,” Phu said. Dr Nguyen Tran Hien, head of the Hygiene and Epidemiology Institute, said that during recent weeks, there have been many cases of virus-caused pneumonia, of which 20 percent are H1N1.    H1N1 virus is not as dangerous as H5N1, but if left untreated, patients can suffer multi-infections that can cause pneumonia and breathing difficulties that may lead to respiratory failure or multi-organ failure , threatening patients’ lives, Dr Hien said. H1N1 virus is dangerous for people with chronic diseases, pregnant women, children and elderly people. In the US and Brazil, the number of people affected by H1N1 is on the rise. In a related development, a 52-year-old man in southern Binh Phuoc Province died of H5N1 avian flu last Saturday, after a week of treatment, health authorities reported This is the first human death from the H5N1 flu virus in 2014. Preventing H7N9 spread The Health Ministry’s Preventive Health Department has recently called on all people’s committees, especially those of northern provinces that border China, to take measures to prevent H7N9 avian flu from spreading into Vietnam from its northern neighbor. “The epidemic can penetrate into Vietnam at any time since there is a large volume of people and goods, including poultry, that travels between the two countries at the border everyday,” said Dr Tran Dac Phu, head of the department. According to the World Health Organization (WHO), a new wave of human infections has swept through China, with three more H7N9 bird flu cases reported in Zhejiang province. Two of them are in a critical condition. The WHO said more than 40 cases were confirmed in China in the first three weeks of January. The H7N9 bird flu virus, which emerged in March 2013, has so far infected at least 199 people in China, Taiwan and Hong Kong, killing 52 of them, according to an update from the WHO's spokesman Gregory Hartl, Reuters reported. H7N9 virus can be transmitted from human to human as seen in a number of certain cases in China, the WHO said on Monday. The organization also warned that flu viruses could spread more widely in China with the upcoming holiday travel rush around the coming lunar New Year. The H7N9 virus has been found in poultry in 12 provinces in China. TUOITRENEWS