ObjectiveTo evaluate the prevalence of occult hepatitis B infection in blood donors and to explain the possible molecular mechanfism of occult hepatitis B infection.Methods Enzyme linked immunosorbent assay (ELISA) method was used for detection of hepatitis B virus (HBV)markers in serum samples of 594 donors which were collected from blood bank with HBsAg negative results.Nested-polymerase chain reaction (PCR) was performed to detect serum HBV DNA.In donors with occult HBV infection,the serum HBV markers were quantitatively detected by Abbott nested-PCR kit.The PCR products of S region were sequenced and sequence alignment was performed to analyze relevant virus mutations.Eleven HBsAg positive patients were randomly recruited as positive controls and S region was amplified and sequenced.The difference of S region sequences was compared between patients with occult HBV infection and HBsAg positive HBV infection.ResultsAmong 594 HBsAg negative donors,15 were diagnosed with occult HBV infection with the incidence of 2.5 ％.No correlation was found between results of serum HBV markers and occult HBV infection.Sequencing results of HBV S region were obtained from 10 cases,which revealed mutations of HBV.The amino acid mutations in the “a” determinant cluster were found in three patients,which were I126T,T140I and T140I,respectively.On the contrast,mutation in the “a” determinant cluster of T131 N was only found in one positive control.ConclusionsThe occult HBV infection exists in blood donors with negative results for HBsAg test.Genetic mutation may play a role in the occult HBV infection.

Objective To analyze the epidemiology and clinical characteristics of the children with measles. Methods Retro-spectively analyzed methods were applied to analyze the timing, and season of the break, age distribution, clinical manifestations and major complications of 3431 children with measles (<12 years) in the Second Hospital of Nanjing from 2008 to 2015. Results It found that there was a peak incidence of measles in children each in 2009, 2013, and 2015 , peaking in March to May. Onset age of measles mainly within the first year of life, and incidence increased with age within the first 8 months. Typical clinical manifestations are mainly fever, rash, cough, and catarrhal symptoms. The main complications of measles were pneumonia, laryngitis and heart failure. Conclusions Early diagnosis and effective treatment of the children with measles needs to be strengthened.

Objective To analyze the clinical characteristics ,treatment and outcome of Ebola virus disease so as to provide early clinical recognition and treatment for this disease .Methods The clinical manifestations and treatment of 5 cases of Ebola virus disease in Ebola Holding Center of Sierra‐Leone China Friendship Hospital from 15 March 2015 to 15 May 2015 were retrospectively analyzed .And the clinical characteristics and possible effective treatment were discussed combined with related literature . Results Five patients were diagnosed with Ebola virus disease by polymerase chain reaction and 4 cases of 5 patients had confirmed contact history ,while 1 case had no clear contact history .All the 5 cases presented with low fever ,headache and joint pain .Three cases then progressed into severe gastrointestinal symptoms such as nausea ,vomiting ,diarrhea and hypovolemic shock .The patients presented with fast heart rate and shortness of breath and other inflammatory response syndrome in acute phase .One patient rapidly progressed to liver pain ,jaundice and anuria ,then died .Three severe cases recovered after treated with fluid resuscitation ,circulation maintenance and electrolyte balance in acute phase .Conclusions The early symptoms of Ebola virus disease are low fever ,joint pain and nausea .Frequent vomiting ,diarrhea , low blood pressure and electrolyte disorder indicate severe conditions .Shock and electrolyte disorder are deadly complications .Early recognition ,diagnosis and treatment are the key to improve the prognosis .