Epidemiology of human infections with avian influenza A(H7N9) virus in China.

BACKGROUND: The first identified cases of avian influenza A(H7N9) virus infection in humans occurred in China during February and March 2013. We analyzed data obtained from field investigations to describe the epidemiologic characteristics of H7N9 cases in China identified as of December 1, 2013. METHODS: Field investigations were conducted for each confirmed case of H7N9 virus infection. A patient was considered to have a confirmed case if the presence of the H7N9 virus was verified by means of real-time reverse-transcriptase-polymerase-chain-reaction assay (RT-PCR), viral isolation, or serologic testing. Information on demographic characteristics, exposure history, and illness timelines was obtained from patients with confirmed cases. Close contacts were monitored for 7 days for symptoms of illness. Throat swabs were obtained from contacts in whom symptoms developed and were tested for the presence of the H7N9 virus by means of real-time RT-PCR. RESULTS: Among 139 persons with confirmed H7N9 virus infection, the median age was 61 years (range, 2 to 91), 71% were male, and 73% were urban residents. Confirmed cases occurred in 12 areas of China. Nine persons were poultry workers, and of 131 persons with available data, 82% had a history of exposure to live animals, including chickens (82%). A total of 137 persons (99%) were hospitalized, 125 (90%) had pneumonia or respiratory failure, and 65 of 103 with available data (63%) were admitted to an intensive care unit. A total of 47 persons (34%) died in the hospital after a median duration of illness of 21 days, 88 were discharged from the hospital, and 2 remain hospitalized in critical condition; 2 patients were not admitted to a hospital. In four family clusters, human-to-human transmission of H7N9 virus could not be ruled out. Excluding secondary cases in clusters, 2675 close contacts of case patients completed the monitoring period; respiratory symptoms developed in 28 of them (1%); all tested negative for H7N9 virus. CONCLUSIONS: Most persons with confirmed H7N9 virus infection had severe lower respiratory tract illness, were epidemiologically unrelated, and had a history of recent exposure to poultry. However, limited, nonsustained human-to-human H7N9 virus transmission could not be ruled out in four families.

[Epidemiologic characteristics of hand-foot-mouth disease in Guiyang between 2008 and 2010].

OBJECTIVE: To study the epidemiologic characteristics of hand-foot-mouth disease (HFMD) in Guiyang between 2008 and 2010. METHODS: The epidemiologic characteristics of HFMD were analyzed by descriptive statistical methods based on the data from the China Information System for Disease Control and Prevention. RESULTS: A total of 27383 cases of HFMD were recorded in Guiyang between 2008 and 2010. The incidence of HFMD increased from 66.4439/100000 in 2008 to 163.9276/100000 in 2009 and 471.5515/100000 in 2010 (P<0.01). The mortality rate was 0.1026/100000 in 2010, which was significantly lower than in 2009 (0.2821/100000) (P<0.05). HFMD occurrence showed seasonality and reached a peak between April and June. HFMD cases were commonly noted in children under 5 years old, and especially in children under 3 years old. The main detected pathogen was human enterovirus 71 (EV17) in 2009. Whereas in 2010 the disease was mainly caused by CoxA16 and other intestinal viruses. CONCLUSIONS: The incidence of HFMD in Guiyang increased year by year from 2008 to 2010, but the mortality rate decreased year by year. HFMD occurrence showed an obvious seasonality. HFMD was common in children under the age of five. The main pathogens of this disease included EV17, CoxA16 and other intestinal viruses.

[Investigation on the causes of increased hepatitis E cases reported in Guizhou province].

OBJECTIVE: To analyze causes of growing hepatitis E (HE) cases reported in Guizhou province, and probe into existing problems faced by medical institutions in diagnosis of clinical and laboratory-confirmed cases, for the purpose of improving the quality of HE surveillance system. METHODS: Six hospitals reporting greater HE cases from 2007 to 2011 were pinpointed, whose reported cases rose suddenly in 2011. Such cases were investigated by means of impatient medical record review, results of laboratory test and clinician interview. RESULTS: 136 of the 354 reported HE cases investigated were found compliant with the diagnostic criteria of HE with an accordance rate of 38.42%. Difference of the HE diagnostic accordance rate among individual years, hospitals and reporting departments was statistically significant. Such rate of hospital reports was found to be the lowest in 2011, ranging from 0 to 18.18% respectively; HE cases reported by non-infectious departments accounted for 61.30% of total cases reported, with its accordance rate considerably below the infectious departments (8.29%). HE positive cases and HE positive rate in 2011 were significantly higher than that of preceding years. CONCLUSION: Such increase of reported HE cases in 2011 in the province was mostly attributable to more HE laboratory tests made by the hospitals, yet the accordance rates were lower than satisfactory. In this regard, the medical institutions in question were advised to enhance their competency training for HE diagnosis and case report quality.