Clinical and epidemiologic features of Coxsackievirus A6 infection in children in northern Taiwan between 2004 and 2009.

BACKGROUND: Isolates of Coxsackievirus A6 (Cox A6) is increasing clinically in 2009 in Taiwan but detailed clinical features of Cox A6 infections in children have not been reported. This study is to define clinical manifestations and laboratory findings of Cox A6 infection in children. METHODS: From January 2004 to December 2009, a total of 4,664 children with enterovirus infections, based on throat virus culture, were treated in Chang Gung Children's hospital. Two hundred and ninety-six (6.3%) patients positive for Cox A6 infection were included in this study. One hundred and forty-one (47.6%) inpatients were further analyzed for clinical presentations, laboratory findings, and clinical diagnoses. RESULTS: There were two peaks of Cox A6 infection in 2007 and 2009 during the study period, especially during the warm season. The proportion of Cox A6 among total enterovirus isolates was 15.5% in 2007 and up to 22.2% in 2009. The mean age of inpatients was 2.42 ± 0.14 years. The mean hospitalization duration was 4.21 ± 0.11 days. The most common symptoms were fever (100%), oral ulcers (90.8%), and decreased oral intake (89.4%). The mean duration of fever was 2.78 ± 1 days (range, 1-7 days). Seventy-seven (54.6%) patients had fever more than 3 days. The mean leukocyte count was 14,850/mm(3), and 63 (45%) patients had leukocytosis (>15,000/mm(3)). The mean serum C-reactive protein (CRP) level was 44.1 ± 3.3 mg/L (normal, <10 mg/L) and 62 (44%) had a CRP level >40 mg/L. One hundred and eight (76.6%) inpatients were diagnosed as herpangina and 18 (12.8%) hand-foot-mouth disease. Three patients had complications, including aseptic meningitis in one and encephalitis in two. All 141 inpatients recovered uneventfully. CONCLUSIONS: Cox A6 is among the major serotypes of enteroviruses in Taiwan and most cases presented as herpangina and hand-foot-mouth disease. Nearly half of the cases may have leukocytosis and elevated CRP levels. Outcomes are usually good.

Comparison of clinical features between coxsackievirus A2 and enterovirus 71 during the enterovirus outbreak in Taiwan, 2008: a children's hospital experience.

BACKGROUND/PURPOSE: Coxsackievirus A2 (Cox A2) was the predominant serotype in the enterovirus outbreak in Taiwan, 2008. However, detailed clinical features of Cox A2 infection have not been reported. In this study, we compared Cox A2 with enterovirus 71 (EV71) in terms of clinical manifestation and epidemiology during the 2008 enterovirus outbreak in Taiwan. METHODS: A total of 280 hospitalized patients (97 with culture-proven EV71 infection and 183 with culture-proven Cox A2 infection) in 2008 at the Chang Gung Children's Medical Center were enrolled in this study. Epidemiologic data, clinical manifestations, and outcomes for these patients were collected and compared. RESULTS: Both Cox A2 and EV71 serotypes peaked in June and declined soon afterwards. Seventy-one percent of the patients were younger than 3 years of age. Both groups had the same male-to-female ratio of 1.6:1. Patients with EV71 infection had a significantly longer hospitalization period (4.1 vs. 3.0 days, p< 0.001). Fever, fever for more than 3 days with a temperature above 39 degrees C, lethargy, poor activity, poor appetite and a myoclonic jerk were significantly associated with EV71 infection. Fever, or fever with a temperature above 39 degrees C, febrile seizure, elevated white cell counts, and elevated serum C-reactive protein concentrations were significantly associated with Cox A2 infection. Most patients with EV71 infection presented with hand-foot-mouth disease (78.3%), while most Cox A2-infected patients presented with herpangina (83.6%). Central nervous system complications were found in 18.6% of EV71-infected children, but only in 1.1% of Cox A2-infected children. All the patients with Cox A2 infection showed total recovery. One patient with EV71 infection died from encephalitis with cardiopulmonary failure, and 6.2% of EV71-infected children had neurologic sequelae. CONCLUSION: Both Cox A2 and EV71 serotypes accounted for the enterovirus outbreak in Taiwanese children in 2008. Compared with those infected by EV71, the children with Cox A2 infection mostly presented with herpangina, had fewer central nervous system complications, and had better overall outcome.

An investigation of epidemic enterovirus 71 infection in Taiwan, 2008: clinical, virologic, and serologic features.

BACKGROUND: Enterovirus 71 (EV71) is causing life-threatening hand-foot-mouth disease in Asia. In Taiwan, EV71 epidemics with different predominant genotypes occurred in 1998 (C2), 2000-2001 (B4), and 2004-2005 (C4). This genotype replacement may have important implications for vaccine development and prediction of epidemics. A nationwide EV71 outbreak occurred again in 2008, which provided a unique opportunity to characterize clinical, virologic, and serologic features of this epidemic. METHODS: We analyzed clinical and virologic data of 111 EV71 patients hospitalized in 2008 and prospectively conducted follow-ups of healthy children from June 2006 to December 2008. RESULTS: Among the 111 EV71 inpatients, 21 (19%) developed complications. Among the 21 complicated cases, 15 had central nervous system complication only, 2 had acute heart failure, and 4 had central nervous system and pulmonary complications. In the prospective study, 11 symptomatic infections and 4 asymptomatic infections were detected. Twenty-two EV71 isolates were genotyped, and 21 of them belong to genotype B5, which is phylogenetically close to B5 viruses circulating in Southeast Asia. Serologic tests show that children infected with B5 viruses have lower geometric mean titers of neutralizing antibody against genotype C4 than those against genotype B5 (P = 0.004, t test). CONCLUSIONS: The 2008 nationwide EV71 epidemic was caused by genotype B5 that was likely introduced to Taiwan from Southeast Asia. Clinical features of the 2008 epidemic were not different from those observed before in Taiwan. Potential antigenic variations between genotype C4 and B5 viruses could be detected and its long-term epidemiologic significance needs further investigation to clarify.