Investigation of a family clustering of human infection with avian influenza A (H7N9) virus in Nanning, Guangxi / 中华流行病学杂志

<p><b>OBJECTIVE</b>To understand the transmission mode of human infection with avian influenza A (H7N9) virus.</p><p><b>METHODS</b>Field epidemiological investigation was conducted for a family clustering of human infection with H7N9 virus in Hengxian county, Guangxi Zhuang Autonomous Region in February 2014. Two patients and their 82 close contacts were surveyed. The samples collected from the patients, environments and poultry were tested by using real time reverse transcriptase-polymerase chain reaction (rRT-PCR), and the samples from patients were used for virus isolation. The samples from 5 close contacts were tested with RT-PCR. The clinical data, exposure histories of the patients and the detection results of the isolates and their homology were analyzed.</p><p><b>RESULTS</b>Patient A became ill 4 days after her last exposure to poultry in Zhongshan, Guangdong province, and returned to her hometown in Hengxian 2 days after onset. Patient B was patient A's 5 years old son, who had no known exposure to poultry but slept with patient A for 4 days. He developed symptoms 4 days after last contact with his mother. Two strains of H7N9 virus were isolated from the two patients. The 2 isolates were highly homogenous (almost 100%) indicated by gene sequencing and phylogenetic tree. None of the other 81 close contacts developed symptoms of H7N9 virus infection.</p><p><b>CONCLUSION</b>Patients B was infected through close contact with patient A, indicating that avian H7N9 virus can spread from person to person, but the transmissibility is limited and non-sustainable.</p>

Impact of extreme low temperature and rainy weather on epidemic of infectious diseases in Nanning / 重庆医学

Objective To analyze impact of extreme low temperature and rainy weather on epidemic of infectious diseases in Nanning City and to provide a scientific basis of preventing and controlling infectious diseases caused by extreme weather events . Methods The data about incidences of respiratory tract infectious diseases ,enteric infectious diseases ,vector-borne infectious disea-ses ,natural foci of diseases from December 2007 to March 2008 and from December 2011 to April 2012 were analyzed by χ2 test . Results The incidence of respiratory tract infectious diseases were influenced greatest by extreme low temperature and rainy weather than other infectious diseases .The incidence of infectious diseases showed hysteresis effect of climate .Incidences of respira-tory tract infectious diseases ,enteric infectious diseases ,vector-borne infectious diseases ,natural foci of diseases during extreme low temperature and rainy weather were significantly higher than that during the same period of other years .And incidences of these were highest during the first 3 months of 2012 .Conclusion Extreme low temperature and rainy weather in Nanning City have im-pact on the incidence of infectious diseases ,which increased the incidence of infectious diseases at different degree .Ventilation and exposure clothes and quilts in the sun are not feasible during low temperature and rainy weather ,therefore health habits should be maximum emphasized when encountering extreme climate events .