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A national surveillance system on hand, foot, and mouth disease (HFMD) was launched in 2008 in China. Since then, millions of HFMD cases have been reported each year, with enterovirus A71 (EV-A71), coxsackievirus A16 (CV-A16), and coxsackievirus A6 (CV-A6) as the major causative pathogens. Long-term surveillance of viral infection rates and genetic changes is essential for understanding the disease epidemiology pattern. Here, we analyzed molecular surveillance data on CV-A16 covering a period of 12 years (2008-2019) in Guangdong, China, one of the regions reporting the largest number of HFMD cases. Full VP1 sequences of 456 strains were determined to examine the genetic diversity and changes in the distribution of CV-A16 variants. Our study revealed an irregular pattern of CV-A16 infections in Guangdong. Different from the cyclic epidemics observed in some Asia-Pacific regions, there was a continuously high CV-A16 infection rate from 2008 to 2014, and after a period of lower epidemic activity in 2015-2017, an upsurge of CV-A16 infection was observed in 2018-2019. Cocirculation of subgenotypes B1a and B1b was observed, but while subgenotype B1a was predominant from 2008 to 2012, it appears to have been replaced by B1b, which has circulated as the predominant subgenotype since 2013. Phylogenetic analysis showed that most of the circulating CV-A16 strains are endemic, with occasional transmission between neighboring regions. The re-emergence of B1a in 2016-2019 in Guangdong was likely the result of introduction(s) from Southeast Asia. These results highlight the importance of continuous molecular surveillance from different areas, which will improve our understanding of the origin of the epidemic and facilitate the development of strategies for HFMD disease control. [ABSTRACT FROM AUTHOR]

Background: An explosive outbreak of dengue fever occurred in Guangdong Province, China in 2014. A community-based integrated intervention was applied to control this outbreak in the capital city Guangzhou, where dengue epidemic was mainly caused by imported cases. Methodology/Principal Findings: We used a time series generalized additive model based on meteorological factors to assess the effectiveness of this intervention. The results showed that there was significant reduction in mosquito density following the intervention, and there was a 70.47% (95% confidence interval: 66.07%, 74.88%) reduction in the reported dengue cases compared with the predicted cases after 12 days since the beginning of the intervention, we estimated that a total of 23,302 dengue cases were prevented. Conclusions: This study suggests that an integrated dengue intervention program has significant effects to control a dengue outbreak in areas where dengue epidemic was mainly caused by imported dengue cases. [ABSTRACT FROM AUTHOR]