Changes in the Circadian Rhythm of High-Frequency Heart Rate Variability Associated With Depression

Background@#Heart rate variability (HRV) extracted from electrocardiogram measured for a short period during a resting state is clinically used as a bio-signal reflecting the emotional state. However, as interest in wearable devices increases, greater attention is being paid to HRV extracted from long-term electrocardiogram, which may contain additional clinical information. The purpose of this study was to examine the characteristics of HRV parameters extracted through long-term electrocardiogram and explore the differences between participants with and without depression and anxiety symptoms. @*Methods@#Long-term electrocardiogram was acquired from 354 adults with no psychiatric history who underwent Holter monitoring. Evening and nighttime HRV and the ratio of nighttime-to-evening HRV were compared between 127 participants with depressive symptoms and 227 participants without depressive symptoms. Comparisons were also made between participants with and without anxiety symptoms. @*Results@#Absolute values of HRV parameters did not differ between groups based on the presence of depressive or anxiety symptoms. Overall, HRV parameters increased at nighttime compared to evening. Participants with depressive symptoms showed a significantly higher nighttime-to-evening ratio of high-frequency HRV than participants without depressive symptoms. The nighttime-to-evening ratio of HRV parameters did not show a significant difference depending on the presence of anxiety symptoms. @*Conclusion@#HRV extracted through long-term electrocardiogram showed circadian rhythm. Depression may be associated with changes in the circadian rhythm of parasympathetic tone.

Epidemiological Investigation of a Measles Outbreak in Seoul, 2013~2014

Korea declared in 2006 that measles had been eliminated; however, a measles outbreak occurred in the southeastern area of Korea in 2011. Active surveillance of measles patients was conducted in Seoul 3 cases were detected in 2013 and 103 cases in 2014. Of 106 confirmed measles patients, 32 cases were within one university in Seongbukgu, and 23 were within three schools in Yongsangu. Students 14~29 years old comprised 78.3% (83/106) of the cases, and 75.5% (80/106) of the measles viruses were of genotype B3. One foreign traveler played an important role in the measles outbreak in Seoul. This measles outbreak in Seoul may provide useful data for future epidemiological studies of measles.

Human Norovirus Genogroups Detected from Acute Gastroenteritis Patients in Seoul from May 2013 to April 2015

Norovirus is an important cause of acute nonbacterial gastroenteritis in communities worldwide. It was evaluated the prevalence of norovirus infections in patients with acute gastroenteritis occurring in Seoul from May 2013 to April 2015, with regular surveillance. 7.3% (252/3,485) of the fecal specimens were determined to be positive for noroviruses by reverse transcription-polymerase chain reaction (RT-PCR). Norovirus genogroup distribution was 19.1% (48/252) genogroup GI, 71.4% (180/252) genogroup GII, and 9.5% (24/252) genogroup G1+GII respectively. It was most norovirus detection rates from November 2013 to March 2015. And it was rotavirus 0.2% (7/3,485), astrovirus 0.03% (1/3,485), sapovirus 0.03% (1/3,485) and, it was non-detective on adenovirus. Norovirus genotypes identified were nine kinds of genogroup GI (GI-1, GI-2, GI-3, GI-4, GI-6, GI-7, GI-8, GI-12, GI-14) and eight kinds of genogroup GII (GII-2, GII-3, GII-4, GII-5, GII-6, GII-7, GII-14, GII-16, GII-17). The genetic characteristics of norovirus and the epidemiological patterns of a viral pathogen from acute gastroenteritis patients may give potentially effective data for epidemiological studies in Seoul, Korea.