Objective: To estimate total numbers of undiagnosed carriers of hepatitis C virus (HCV) and hepatitis B virus (HBV) in Japan. Methods: Area- and age-specific prevalence of HCV as well as HBV was determined in the first-time blood donors [20–39 years (n = 2,429,364)] and examinees of periodical health check-ups [40–74 years (6,204,968 for HCV and 6,228,967 for HBV)] in Japan. Prevalence in adolescents [5–19 years (79,256 for HCV and 68,792 for HBV)] was determined in a single prefecture, and that of HCV in the elderly (≧75 years) was estimated by the exponential model. HBV infection was determined by the detection of hepatitis B surface antigen, and HCV infection by either the algorithm or assuming persistent infection in 70% of the individuals with antibody to HCV. Results: Of the total population of 127,285,653 in 2005, 807,903 (95% CI 679,886–974,292) were estimated to be infected with HCV at a carrier rate of 0.63%, and 903,145 (837,189–969,572) with HBV at that of 0.71%. Conclusion: Accurate estimation of undiagnosed HCV and HBV carriers in the general population would help to predict the future burden of liver disease, and take appropriate measures for improving healthcare.

Although the mortality rate due to hepatocellular carcinoma (HCC) has been gradually decreasing in Japan, approximately 30 000 people died of HCC in 2016. In 2007, the dominant etiology was persistent hepatitis C virus (HCV) infection, which accounted for 65% of total HCC deaths, and 15% of cases were due to chronic hepatitis B virus (HBV) infection. In managing chronic HBV and HCV infection, it is critically important to know the exact number of infected individuals in a particular country, which then assists in evaluating medical and financial needs in the foreseeable future. Therefore, from an epidemiological perspective, we estimated the numbers of HBV and HCV carriers in four categories: (i) undiagnosed carriers; (ii) carriers who were already hospitalized as patients or were receiving outpatient medical attention; (iii) diagnosed carriers who had not consulted any medical facility, or had discontinued consultation; and (iv) newly infected carriers. From these estimates we determined the current HBV and HCV burden and then reviewed the existing countermeasures for their prevention and control in Japan. While continuing the surveillance on the dynamics of hepatitis virus infections linked with preventive measures against hepatitis virus infection, it is crucially important to promote appropriate measures for each of the four groups of hepatitis virus carriers in society.

Summary We estimated the total number of undiagnosed HBV and HCV carriers and patients with hepatitis virus‐related disease in Japan according to 6 different groups classified by their natural histories during 2011. In 2011, the total number of carriers and patients infected with HBV or HCV was estimated according to 6 groups using government reports and reports from the hepatitis epidemiology research group of The Ministry of Health, Labor and Welfare in Japan. In 2011, the total number of hepatitis virus carriers was estimated to be 2 090 128‐2 840 128 in which the estimated number of undiagnosed HCV and HBV carriers was 776 826 (HBV: 481 470; HCV: 295 356). The total number of treated patients, as either inpatients or outpatients, was estimated to be 811588 (HBV: 303 366; HCV: 520 600) in 2011. It is presumed that many carriers shirk consultation for many reasons, such as patients’ misunderstanding, lack of awareness and forgetfulness of their positive status. The numbers of infected patients who did not seek treatment increased gradually to 501 714‐1 251 714 (HBV: 333 791‐483 791; HCV: 167 923‐767 923) in 2011. Compared to 2000, the number of undiagnosed carriers was significantly reduced in 2011 probably because of the well‐organized, effective national hepatitis virus screening system that has been launched by the Japanese government since 2002. Moreover, the increase in the number of untreated persons who are aware of their positive status shows that more effort should be invested in improving the referral system from screening centres to core hospitals.

Our results showed that operation and blood transfusion were potential risk factors for HBV and HCV infection, respectively, and supposed that horizontal HBV transmission may be frequent in adults in Cambodia. Hence, for reducing HBV and HCV infections, it is necessary to improve the safety of blood and medical treatment.

Objective: The aim of the study was to evaluate the survival benefits of liver resection (LR) compared with transarterial chemoembolization (TACE) for patients with multiple hepatocellular carcinomas (HCCs). Background: Despite significant improvements in diagnostic imaging and the widespread application of screening programs, some patients with HCC continue to present with multiple tumors. The surgical indications for multiple HCCs remain controversial. Methods: Among 77,268 patients with HCC reported in a Japanese nationwide survey, 27,164 patients had multiple HCCs. The exclusion criteria were Child-Pugh B/C, treatment other than LR and TACE, >3 tumors, and insufficient available data. Ultimately, 3246 patients (LR: n = 1944, TACE: n = 1302) were included. The survival benefit of LR for patients multiple HCCs was evaluated by using propensity score matching analysis. Results: The study group of 2178 patients (LR: n = 1089, TACE: n = 1089) seemed to be well matched. The overall survival rate in the LR group was 60.0% at 5 years, which was higher than that in the TACE group (41.6%, P < 0.001). Among patients with a tumor size of 30 mm or more, LR showed a survival benefit over TACE at 5 years (53.0% vs 32.7%, P < 0.001). The multivariate analysis indicated that age, serum albumin level, serum alpha-fetoprotein (AFP) level, macrovascular invasion, tumor size, and TACE were independent predictors of poor prognosis in multiple HCCs. Conclusions: LR could offer better long-term survival than TACE for patients with multiple HCCs (up to 3 tumors). If patients have good liver function (Child-Pugh A), LR is recommended, even for those with multiple HCCs with tumor sizes of 30 mm or more.

This cross-sectional study aimed to investigate the post-acute consequences of COVID-19. We conducted a self-administered questionnaire survey on sequelae, psychological distress (K6), impairments in work performance (WFun), and COVID-19–related experiences of stigma and discrimination in two designated COVID-19 hospitals in Hiroshima Prefecture, Japan, between August 2020 and March 2021. The prevalence of sequelae was calculated by age and COVID-19 severity. Factors independently associated with sequelae or psychological distress were identified using logistic regression analysis. Among 127 patients who had recovered from COVID-19, 52.0% had persistent symptoms at a median of 29 days [IQR 23–128] after COVID-19 onset. Among patients with mild COVID-19, 49.5% had sequelae. The most frequent symptoms were olfactory disorders (15.0%), taste disorders (14.2%), and cough (14.2%). Multivariate analysis showed that age was an independent risk factor for sequelae (adjusted odds ratios [AOR] for ≥ 60 years vs. < 40 years 3.63, p = 0.0165). Possible psychological distress was noted in 30.7% (17.9% of males and 45.0% of females). Female sex and the presence of sequelae were independent risk factors for psychological distress. Of all participants, 29.1% had possible impairments in work performance. Experiences of stigma and discrimination were reported by 43.3% of participants. This study revealed the significant impacts of Long COVID on health in local communities. A large-scale, long-term cohort study is desired.

In Binh Thuan, prevalences of HBV and HCV infections are high, HBV genotype B and HCV genotype 6a are predominant, and horizontal HBV transmission may still occur. Therefore, raising the coverage of a universal HBV vaccination program may be an effective liver cancer control in Vietnam.

Introduction The BNT162b2 and mRNA-1273 COVID-19 vaccines are the main vaccines that have been used for mass vaccination in Japan. Information on adverse reactions to COVID-19 vaccines in the Japanese population is limited. Methods We conducted an online survey on self-reported adverse reactions in individuals who had received two doses of the BNT162b2 mRNA or mRNA-1273 vaccine. The incidence of adverse events after each dose of vaccine was investigated. Propensity score matching was used to compare the incidence of adverse reactions after the second dose of the BNT162b2 mRNA and mRNA-1273 vaccines. Results After the first and second doses of the BNT162b2 vaccine, and the first and second doses of the mRNA-1273 vaccine, 890, 853, 6401, and 3965 individuals, respectively, provided complete responses. Systemic reactions, including fever, fatigue, headache, muscle/joint pain, and nausea were significantly more common in females, individuals aged <50 years, and after the second dose. The incidence of injection site pain did not differ significantly according to the dose. The incidence of delayed injection site reactions after the first dose of mRNA-1273 vaccine was 3.9% and 0.8% among females and males, respectively, and 10.6% among females aged 30–69 years. Local and systemic reactions after the second dose, including fever, fatigue, headache, muscle/joint pain, nausea, and skin rash were more common in individuals who had received the mRNA-1273 vaccine. Conclusions Adverse reactions were more frequently reported in females, younger individuals, and after the mRNA-1273 vaccine.