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Dengue used to be recognized as an imported and sporadic disease in China. Since June 2014, an unexpected large dengue outbreak has attacked Guangzhou, China, resulting in more than 40,000 cases. Among the 1,942 laboratory-confirmed hospitalized dengue cases, 121 were diagnosed as severe dengue according to the 2009 WHO guideline, and 2 patients finally died. Laboratory diagnosis and virus isolation demonstrated that the majority (96%) cases were caused by dengue virus serotype 1 (DENV-1), and the others by serotype 2 (DENV-2). 14 DENV strains were isolated from the sera of acute-phase dengue patients during this outbreak, and the complete envelope (E) gene of 12 DENV-1 strains and two DENV-2 strains were determined using RT-PCR assay. Phylogenetic analysis based on the E gene revealed the DENV-1 strains isolated during the outbreak belonged to genotype I and V, respectively. These isolates formed three clades. DENV-2 isolates were assigned to the same clade belonging to genotype cosmopolitan. These strains isolated in 2014 were closely related to the isolates obtained from the same province, Guangdong, in 2013. No amino acid mutations known to increase virulence were identified throughout the E protein of isolates in 2014. These results indicate that dengue is turning into endemic in Guangdong, China, and extensive seroepidemiological investigation and mosquito control measures are critically needed in the future. [ABSTRACT FROM AUTHOR]

Abstract: Eight geographic populations of Brachionus calyciflorus collected from China in August 2007 were cultured at 18°C, 23°C and 28°C with 3.0×106 cellsmL−1 of alga Scenedesmus obliquus to investigate their differences in life table demography. The results showed that the response in each of the life table demographic parameters (age-specific survivorship and fecundity, life expectancy at hatching, generation time, net reproductive rate, intrinsic rate of population increase and proportion of sexual offspring) to increasing temperature differed with geographic population. Life expectancy at hatching, generation time, net reproductive rate and intrinsic rate of population increase were all significantly influenced by temperature, geographic population and their interaction and indirectly affected by the changes in body size and egg volume of the rotifers; however, the proportion of sexual offspring produced by the rotifers was markedly influenced only by geographic population. Among all the combinations of temperature and geographic population, the generation times of Guangzhou and Hainan populations at 18°C were the longest, and the intrinsic rate of population increase of the Tai’an population at 18°C was the lowest. Among all the eight geographic populations, the proportion of sexual offspring produced by Xuzhou population was the highest. Although the higher proportions of sexual offspring produced by all the geographic populations of rotifers (9.7–41.1%) might lead to higher resting egg productions, and thus to wide spread of the rotifers among the eight geographic populations, their differences in life table demography might be regarded as the results of adaptation to the different environmental conditions faced by them in the field. [Copyright &y& Elsevier]