JYNNEOS vaccine safety monitoring in the Republic of Korea, 2022: a cross-sectional study

Objectives@#With the recent global mpox outbreak, the JYNNEOS vaccine (Modified VacciniaAnkara-Bavarian Nordic) was developed as a third-generation smallpox vaccine and initiallyfavored for mpox immunization. Vaccine-associated side effects contribute to vaccinehesitancy. Consequently, tracking adverse events post-immunization is crucial for safety management. This study used data from the national active vaccine safety surveillance conducted in Korea from August 25 to November 24, 2022 to detect potential safety signals and adverse events. @*Methods@#Data on health conditions following vaccination were gathered from web-based surveys and reported via active surveillance through the Immunization Registry Information System. This follow-up system functioned via a text message link, surveying adverse events and health conditions beginning on the second day post-vaccination. Information aboutspecific adverse events, including both local and systemic reactions, was collected. @*Results@#The study included 86 healthcare workers who had received at least 1 dose of the JYNNEOS vaccine. Among the respondents, 79.1% reported experiencing at least 1 adverse event, with the majority being local reactions at the injection site. The incidence of adverse events was higher following the first dose (67.9%) than after the second dose (34.4%). The most frequently reported adverse event for both doses was mild pain at the injection site. @*Conclusion@#The study provides crucial information on the safety of the JYNNEOS vaccine, demonstrating that most adverse events were manageable and predominantly localized to the injection site. Nonetheless, additional research is needed on the safety of various vaccineadministration techniques and the vaccine’s effects on broader demographics.

A Healthcare-Associated Outbreak of HCV Genotype 2a at a Clinic in Seoul

Objectives@#An epidemiological investigation was conducted into a hepatitis C virus (HCV) outbreak at an outpatients clinic in Seoul (2011-2012). The aim of the study was to analyze the scale of infection, identify the source of infection, and route of transmission to prevent hepatitis C transmission in the future. @*Methods@#A retrospective study of the outpatients and health care workers (n = 7,285) in the target outpatient clinic during 2011-2012 was conducted. The history of the study population infection with hepatitis C, electronic medical records, field visits, and health care worker interviews were examined for the period between March 1>st , 2006 and March 25th , 2016. The blood samples were collected and tested for anti-HCV antibodies, HCV RNA and HCV gene in 2016. @*Results@#The rate of anti-HCV positive results was 4.4% in the study population. The risk factors associated with an anti-HCV positive result were ≥ 10 clinic visits, and receiving an invasive procedure including a nerve block and a block of the peripheral branch of the spinal nerve (p < 0.05). There were 112 HCV RNA positive cases out of 320 anti-HCV positive test result cases, amongst which 100 cases had the dominant HCV genotype 2a which formed either 1 cluster (n = 56) or 2 clusters (n = 25). This result indicated exposure to a high-association infection source. @*Conclusion@#Anti-HCV antibodies and genotypic analysis showed an epidemiological association between the outbreak of HCV and invasive procedures performed (2011-2012) at an outpatients clinic in Seoul.

Epidemiological Investigation of the Outbreak of Acute Respiratory Infection caused by Adenovirus Type B55 in a Physical Education School in 2017 / 감염과화학요법

BACKGROUND@#On May 19, 2017, the cluster of 6 acute respiratory infections due to adenovirus in the swimming department of a physical education school (School J) was reported to Korea Centers for Disease Control and Prevention. An epidemiological investigation was conducted to identify the transmission route of the infection and to control the outbreak.@*MATERIALS AND METHODS@#A retrospective cohort study (Study 1) was conducted on students and teachers of the athletic departments using the swimming pool, and a prospective surveillance (Study 2) was conducted on all students and teachers of the School J. A case was defined as any student and school personnel who developed more than two of the following symptoms from April 10 to July 2, 2017: fever, sore throat, cough, rhinorrhea, or headache. Relative risks (RRs) were calculated to compare the attack rates according to potential risk factors. Multivariable logistic regression was performed to identify the risk factors for infection in the outbreak.@*RESULTS@#47 cases were identified: 33 (55.9%) cases occurred among 59 students and teachers in Study 1 and 14 (3.9%) among 362 students and school personnel in Study 2. There were 18 laboratory confirmed adenovirus infection cases. The common symptoms were headache (71.7%), fever (69.6%), rhinorrhea (63.0%), sputum (56.5%), and sore throat (54.3%). 23.9% of the cases were accompanied with diarrhea and 19.6% with eye congestion. None of the cases developed pneumonia. 32.6% of the cases were hospitalized. In Study 1, attack rate in the swimming department was higher than that in others (RR: 1.90; 95% confidence interval [CI]: 1.01-3.60). In Study 2, being a member of the shooting department (RR: 20.70; 95% CI: 4.90-87.47) and being a first year high school student (RR: 10.95; 95% CI: 2.90-41.33) were identified as risk factors for the infections. Genetic analyses of the adenoviruses showed 100% identical sequence in homology and confirmed the human adenovirus B55 (HAdV-B55). No adenovirus was detected at examining the water and environment of the swimming pool and dormitory.@*CONCLUSION@#The outbreak is inferred to be occurred via propagated transmission among the students in the same athletic department, while the students with symptoms of respiratory infection continued performing school activities without any restrictions. Infection control measures such as early detection of symptoms of respiratory infection and restriction of group activity are necessary to prevent respiratory infection outbreak in the communal living setting.

Treatment of herpes zoster with ultrasound-guided superficial cervical plexus block

Herpes zoster most commonly occurs in elderly patients, and usually affects sensory neurons. Therefore, its characteristic symptoms are segmental pain, itching, and sensory changes in the affected areas. A 71-yr-old woman experienced painful herpetic rash on the right cervical 2-4 dermatomes for 16 days. Two days after the onset of the rash, she was diagnosed with herpes zoster, and prescribed 250 mg famciclovir three times a day for 7 days, pregabalin 150 mg twice a day, and tramadol 150 mg once a day for 14 days, by a dermatologist. Despite medication, her pain was rated at an intensity of 6/10 on the numeric rating scale. In addition, she complained of severe itching sensation on the affected dermatomes. Superficial cervical plexus block (SCPB) was performed at the right C4 level with 15 ml 0.5% lidocaine plus triamcinolone 30 mg. Five days after the procedure, pain and itching completely disappeared. SCPB may be an effective option for the treatment of acute pain and itching arising from herpes zoster, and for the prevention of postherpetic neuralgia.

Gut-residing Microbes Alter the Host Susceptibility to Autoantibody-mediated Arthritis

K/BxN serum can transfer arthritis to normal mice owing to the abundant autoantibodies it contains, which trigger innate inflammatory cascades in joints. Little is known about whether gut-residing microbes affect host susceptibility to autoantibody-mediated arthritis. To address this, we fed C57BL/6 mice with water containing a mixture of antibiotics (ampicillin, vancomycin, neomycin, and metronidazol) for 2 weeks and then injected them with K/BxN serum. Antibiotic treatment significantly reduced the amount of bacterial genomic DNA isolated from fecal samples, in particular a gene encoding 16S ribosomal RNA derived from segmented filamentous bacteria. Arthritic signs, as indicated by the arthritic index and ankle thickness, were significantly attenuated in antibiotic-treated mice compared with untreated controls. Peyer's patches and mesenteric lymph nodes from antibiotic-treated mice contained fewer IL-17-expressing cells than those from untreated mice. Antibiotic treatment reduced serum C3 deposition in vitro via the alternative complement pathway. IL-17-/- congenic C57BL/6 mice were less susceptible to K/BxN serum-transferred arthritis than their wild-type littermates, but were still responsive to treatment with antibiotics. These results suggest that gut-residing microbes, including segmented filamentous bacteria, induce IL-17 production in GALT and complement activation via the alternative complement pathway, which cause the host to be more susceptible to autoantibody-mediated arthritis.