[Epidemiological and pathogenic characteristics of cases with severe and fatal hand, foot, and mouth disease caused by other enterovirus in Hebei province, 2013-2017]

Objective: To understand the epidemiological characteristics of cases with severe and fatal hand, foot, and mouth disease (HFMD) caused by other enterovirus in Hebei province, 2013-2017. Genetic characteristics of the main pathogen cosackie virus A6 (CoxA6) were also analyzed to further clarifying the characteristics and rules of genetic evolution on this virus. Methods: Descriptive epidemiological methods were used to analyze the distribution of severe and fatal cases with HFMD caused by other enterovirus in Hebei, 2013-2017. The VP1 sequences of CoxA6 were phylogenetically analyzed, using the Mega 5.2 software package. Results: A total of 86 severe and fatal cases with HFMD caused by other enterovirus were reported, accounting for 1.12%, comparing to all the HFMD caused by other enterovirus. Cases began to rise in April, and peaked in May-July. 65.12% of the cases occurred in children between 1 and 5 years old. The sex ratio between male and female was 1.39∶1. A total of 93.02% of the cases were children outside the child care settings. A total of 39 positive strains were identified, with positive isolation rate as 45.35%. Phylogenetic analysis on the VP1 sequences of CoxA6 strains in this study revealed that CoxA6 strains belonged to sub-genotypes D3a and D3b. Conclusions: Severe and fatal HFMD cases that caused by other enterovirus in Hebei province was with seasonal feature, consistent with the overall trend of this disease, 2013-2017. No new evolutionary branch appeared in the CoxA6 strain.