Residual risk of mother-to-child transmission of HBV despite timely Hepatitis B vaccination: a major challenge to eliminate hepatitis B infection in Cambodia.

BACKGROUND: In countries with intermediate or high hepatitis B virus (HBV) endemicity, mother-to-child transmission (MTCT) represents the main route of chronic HBV infection. There is a paucity of information on HBV MTCT in Cambodia. This study aimed to investigate the prevalence of HBV infection among pregnant women and its MTCT rate in Siem Reap, Cambodia. METHODS: This longitudinal study included two parts, study-1 to screen HBsAg among pregnant women and study-2 to follow up babies of all HBsAg-positive and one-fourth of HBsAg-negative mothers at their delivery and six-month post-partum. Serum or dried blood spot (DBS) samples were collected to examine HBV sero-markers by chemiluminescent enzyme immunoassay (CLEIA), and molecular analyses were performed on HBsAg-positive samples. Structured questionnaires and medical records were used to examine the risk factors for HBV infection. MTCT rate was calculated by HBsAg positivity of 6-month-old babies born to HBsAg-positive mothers and ascertained by the homology of HBV genomes in mother-child pair at 6-month-old. RESULTS: A total of 1,565 pregnant women were screened, and HBsAg prevalence was 4.28% (67/1565). HBeAg positivity was 41.8% and was significantly associated with high viral load (p < 0.0001). Excluding subjects who dropped out due to restrictions during COVID-19, one out of 35 babies born to HBsAg-positive mothers tested positive for HBsAg at 6 months of age, despite receiving timely HepB birth dose and HBIG, followed by 3 doses of HepB vaccine. Hence the MTCT rate was 2.86%. The mother of the infected baby was positive for HBeAg and had a high HBV viral load (1.2 × 109 copies/mL). HBV genome analysis showed 100% homology between the mother and the child. CONCLUSIONS: Our findings illustrate the intermediate endemicity of HBV infection among pregnant women in Siem Reap, Cambodia. Despite full HepB vaccination, a residual risk of HBV MTCT was observed. This finding supports the recently updated guidelines for the prevention of HBV MTCT in 2021, which integrated screening and antiviral prophylaxis for pregnant women at risk of HBV MTCT. Furthermore, we strongly recommend the urgent implementation of these guidelines nationwide to effectively combat HBV in Cambodia.

Dried blood spot-based host genome analysis technique targeting pathological associations with hepatitis B: Development and clinical application in the Cambodian population.

AIM: Reports of patients with hepatitis B have highlighted associations between polymorphisms in the human leukocyte antigen (HLA)-DPB1, CXCL13, and CXCR5 genes and disease pathology. Owing to its potential to contribute to the development of new diagnostic and therapeutic methods, we aimed to establish a reliable host genome analysis technique that can be used in countries with inadequate infrastructure. METHOD: We compared multiple commercially available kits for dried blood spot (DBS)-based sample collection to develop a basic DBS-based host genome analysis technique. We then collected blood samples from Cambodian patients with hepatitis  B and performed single-nucleotide polymorphism genotyping and HLA allele typing by the DBS system. RESULT: We were able to perform single-nucleotide polymorphism genotyping and HLA allele typing with host DNA samples obtained using a combination of a HemaSpot™ filter paper-based device and a SMITEST® EX-R&D DNA extraction kit. The accuracy of genotyping using samples obtained by this method was not inferior to one using samples obtained by venipuncture. In the Cambodian population, significant associations of HLA-DPB1*04:01 with protection against chronic hepatitis B virus (HBV) infection, and HLA-DPB1*05:01 and HLA-DPB1*13:01 with susceptibility to chronic HBV infection were identified. CONCLUSION: Based on the DBS system, we clarified the associations of HLA-DPB1 alleles with chronic HBV infection in the Cambodian population for the first time. Because the DBS is a low-cost, durable, transportable, and easy-to-handle modality, genetic analysis based on the DBS system is a feasible strategy for obtaining a deeper understanding of HBV epidemiology, especially in middle- or low-income countries.

Neutralizing Type I Interferon Autoantibodies in Japanese Patients with Severe COVID-19.

PURPOSE: Autoantibodies (aAbs) to type I interferons (IFNs) have been found in less than 1% of individuals under the age of 60 in the general population, with the prevalence increasing among those over 65. Neutralizing autoantibodies (naAbs) to type I IFNs have been found in at least 15% of patients with life-threatening COVID-19 pneumonia in several cohorts of primarily European descent. We aimed to evaluate the prevalence of aAbs and naAbs to IFN-α2 or IFN-ω in Japanese patients who suffered from COVID-19 as well as in the general population. METHODS: Patients who suffered from COVID-19 (n = 622, aged 0-104) and an uninfected healthy control population (n = 3,456, aged 20-91) were enrolled in this study. The severities of the COVID-19 patients were as follows: critical (n = 170), severe (n = 235), moderate (n = 112), and mild (n = 105). ELISA and ISRE reporter assays were used to detect aAbs and naAbs to IFN-α2 and IFN-ω using E. coli-produced IFNs. RESULTS: In an uninfected general Japanese population aged 20-91, aAbs to IFNs were detected in 0.087% of individuals. By contrast, naAbs to type I IFNs (IFN-α2 and/or IFN-ω, 100 pg/mL) were detected in 10.6% of patients with critical infections, 2.6% of patients with severe infections, and 1% of patients with mild infections. The presence of naAbs to IFNs was significantly associated with critical disease (P = 0.0012), age over 50 (P = 0.0002), and male sex (P = 0.137). A significant but not strong correlation between aAbs and naAbs to IFN-α2 existed (r = - 0.307, p value < 0.0001) reinforced the importance of measuring naAbs in COVID-19 patients, including those of Japanese ancestry. CONCLUSION: In this study, we revealed that patients with pre-existing naAbs have a much higher risk of life-threatening COVID-19 pneumonia in Japanese population.

Sequential dynamics of virological and serological changes in the serum of SARS-CoV-2 infected patients.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral load dynamics in respiratory samples have been studied, but knowledge about changes in serial serum samples of infected patients in relation to their immunological response is lacking. We investigated the dynamics of SARS-CoV-2 viral load and antibody response in sequential serum of coronavirus disease 2019 (COVID-19) patients and attempted to culture the virus in the serum. A total of 81 sequential serum samples from 10 confirmed COVID-19 patients (5 with mild and 5 with moderate symptoms) were analyzed. Samples were collected during hospitalization and after discharge (median follow-up of 35 days). SARS-CoV-2 ribonucleic acid in the serum was detected by real-time polymerase chain reaction. Total antibody and IgG to SARS-CoV-2 Spike protein were analyzed by Chemiluminescent Immunoassays, and neutralizing antibodies were detected using a Surrogate Virus Neutralization Test. Viremia was observed in all cases at admission, and viral copy gradually dropped to undetectable levels in patients with mild symptoms but fluctuated and remained persistent in moderate cases. The viral culture of samples with the highest viral load for each patient did not show any cytopathic change. The antibody response was faster and higher in moderate cases. This study provides a basic clue for infectious severity-dependent immune response, viremia, and antibody acquisition pattern.

Adverse reactions to the BNT162b2 and mRNA-1273 mRNA COVID-19 vaccines in Japan.

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 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 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 40-69 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.

A longitudinal study of anti-SARS-CoV-2 antibody seroprevalence in a random sample of the general population in Hiroshima in 2020.

BACKGROUND: This longitudinal study aimed to determine chronological changes in the seroprevalence of prior SARS-CoV-2 infection, including asymptomatic infections in Hiroshima Prefecture, Japan. METHODS: A stratified random sample of 7,500 residents from five cities of Hiroshima Prefecture was selected to participate in a three-round survey from late 2020 to early 2021, before the introduction of the COVID-19 vaccine. The seroprevalence of anti-SARS-CoV-2 antibodies was calculated if at least two of four commercially available immunoassays were positive. Then, the ratio between seroprevalence and the prevalence of confirmed COVID-19 cases in Hiroshima was calculated and compared to the results from other prefectures where the Ministry of Health, Labour and Welfare conducted a survey by using the same reagents at almost the same period. RESULTS: The numbers of participants in the first, second, and third rounds of the survey were 3025, 2396, and 2351, respectively and their anti-SARS-CoV-2 antibodies seroprevalences were 0.03% (95% confidence interval: 0.00-0.10%), 0.08% (0.00-0.20%), and 0.30% (0.08-0.52%), respectively. The ratio between the seroprevalence and the prevalence of confirmed COVID-19 cases in Hiroshima was 1.2, which was smaller than that in similar studies in other prefectures. CONCLUSIONS: The seroprevalence of anti-SARS-CoV-2 antibodies in Hiroshima increased tenfold in a half year. The difference between seroprevalence and the prevalence of confirmed COVID-19 cases in Hiroshima was smaller than that in other prefectures, suggesting that asymptomatic patients were more actively detected in Hiroshima.

Epidemiologic profile of hepatitis C virus infection and genotype distribution in Burkina Faso: a systematic review with meta-analysis.

BACKGROUND: Detailed characteristics of Hepatitis C virus (HCV) infection in Burkina Faso are scarce. The main aim of this study was to assess HCV seroprevalence in various settings and populations at risk in Burkina Faso between 1990 and 2020. Secondary objectives included the prevalence of HCV Ribonucleic acid (RNA) and the distribution of HCV genotypes. METHODS: A systematic database search, supplemented by a manual search, was conducted in PubMed, Web of Science, Scopus, and African Index Medicus. Studies reporting HCV seroprevalence data in low and high-risk populations in Burkina Faso were included, and a random-effects meta-analysis was applied. Risk of bias was assessed using the Joanna Briggs institute checklist. RESULTS: Low-risk populations were examined in 31 studies involving a total of 168,151 subjects, of whom 8330 were positive for HCV antibodies. Six studies included a total of 1484 high-risk persons, and 96 had antibodies to HCV. The pooled seroprevalence in low-risk populations was 3.72% (95% CI: 3.20-4.28) and 4.75% (95% CI: 1.79-8.94) in high-risk groups. A non-significant decreasing trend was observed over the study period. Seven studies tested HCV RNA in a total of 4759 individuals at low risk for HCV infection, and 81 were positive. The meta-analysis of HCV RNA yielded a pooled prevalence of 1.65% (95% CI: 0.74-2.89%) in low-risk populations, which is assumed to be indicative of HCV prevalence in the general population of Burkina Faso and suggests that about 301,174 people are active HCV carriers in the country. Genotypes 2 and 1 were the most frequent, with 60.3% and 25.0%, respectively. CONCLUSIONS: HCV seroprevalence is intermediate in Burkina Faso and indicates the need to implement effective control strategies. There is a paucity of data at the national level and for rural and high-risk populations. General population screening and linkage to care are recommended, with special attention to rural and high-risk populations.

Eighteen-year follow-up cohort study on hepatitis B and C virus infections related long-term prognosis among hemodialysis patients in Hiroshima.

This study aimed to investigate the prevalence trend of hepatitis B virus (HBV) and hepatitis C virus (HCV) infections and their genotype distribution among hemodialysis patients, determining their long-term prognosis and the risk factors to the mortality. This cohort study used both the medical data and the blood samples of hemodialysis patients at nine dialysis centers in Hiroshima from 1999 to 2017. Hepatitis B surface antigen (HBsAg) and anti-HCV were screened and then amplification was done to positive sera by polymerase chain reaction for genotyping. Data were employed for multiple regressions to determine the associated risk factors. A total of 3968 patients were subdivided into three groups: who started hemodialysis before 1990, during 1991 to 2001, and after 2002. The periodic prevalence of HBsAg decreased from 2.8% to 1.3% and that of anti-HCV from 33.3% to 9.5% in the three groups. By multiple regressions, the adjusted hazard ratio of diabetes mellitus (DM) ranges from 1.59 to 2.12 and that of HCV RNA positivity ranges from 1.18 to 1.48 (P < .05). Heart failure is the primary cause of death in all groups. Genotype C2 is predominant for HBV and genotype 1b is predominant for HCV. The decreasing trend of both HBV and HCV was found in the cohort. DM and HCV RNA were the significant risk factors leading to poor prognosis among hemodialysis patients. The similar genotype distribution of both HBV and HCV was found as general population. This alarmed to provide early diagnosis, prompt, and adequate treatment to HCV infection among hemodialysis patients.

Existence of hepatitis B virus surface protein mutations and other variants: demand for hepatitis B infection control in Cambodia.

BACKGROUND: This study aimed to detect Hepatitis B virus (HBV) genome sequences and their variants as of nationwide scale using dried blood spot (DBS) samples and to provide up-to-date reference data for infection control and surveillance in Cambodia. METHOD: Among 2518 children age 5-7 years and their 2023 mothers participated in 2017 Cambodia nationwide sero-survey on hepatitis B surface antigen (HBsAg) prevalence using multistage random sampling strategy, 95 mothers and 13 children positive to HBsAg were included in this study. HBV DNA was extracted from DBS, then performed polymerase chain reaction. HBV genotypes and potential variants were examined by partial and full length genomic analysis. RESULTS: HBsAg positive rate was 4.7% (95/2023) in mothers and 0.52% (13/2518) in their children. Genotype C (80.49%) was abundantly found throughout the whole Cambodia whilst genotype B (19.51%) was exclusively found in regions bordering Vietnam. S gene mutants of HBV were found in 24.29% of mothers and 16.67% of children with HBV DNA positive sera. Full-length genome analysis revealed the homology of 99.62-100% in each mother-child pair. Genotype B was clarified to recombinant genotype B4/C2 and B2/C2. Double (48.39%) and combination mutation (32.26%) were observed in core promoter region of HBV C1 strains. CONCLUSIONS: This study showed the capable of DBS for large-scale molecular epidemiological study of HBV in resource limited countries. Full-genome sequences yield the better understanding of sub-genotypes, their variants and the degree of homology between strains isolated from mother-child pairs calls for effective strategies on prevention, control and surveillance of mother-to-child HBV transmission in Cambodia.

The changing epidemiology of hepatitis B and C infections in Nanoro, rural Burkina Faso: a random sampling survey.

BACKGROUND: This study sought to provide up-to-date hepatitis B (HBV) and C (HCV) seroprevalence in rural Burkina Faso decade after hepatitis B vaccine was introduced in the national immunization scheduled for children. METHODS: In 2018, a community-based, random sampling strategy with probability proportional to population size was conducted in Nanoro to investigate the prevalence of viral hepatitis in children and their mothers. Sociodemographic, vaccination history and risk factors were assessed by interview and health books. HBsAg rapid tests were done by finger prick and Dried Blood Spots (DBS) were collected for hepatitis seromarkers by chemiluminescence enzyme immunoassay. Positive samples underwent confirmatory PCR and phylogenetic analysis. RESULTS: Data were presented on 240 mother-child pairs. HBsAg Prevalence was 0.8% in children and 6.3% in mothers. Hepatitis B core antibody positivity was 89.2% in mothers, 59.2% in children and was associated with age, sex and scarification. Hepatitis B surface antibodies prevalence was 37.5% in children and 5.8% in mothers. Good vaccination coverage was limited by home delivery. Phylogenetic analysis of HBV strains based on full genome sequences (n = 7) and s-fragment sequences (n = 6) revealed genotype A, E, and recombinant A3/E. Viral genome homology was reported in one mother-child pair. Anti-HCV prevalence was 5.4% in mothers, 2.1% in children and strains belonged to genotype 2. CONCLUSIONS: In Nanoro, HBsAg prevalence was low in children, intermediate in mothers and mother-to-child transmission persists. Home delivery was a limiting factor of Hepatitis B vaccination coverage. HBV genotype E was predominant and genotype A3/E is reported for the first time in Burkina Faso.

The effect of masticatory behaviour on generalized attention in heathy volunteers.

AIM: As our society ages, the number of people living with dementia also steadily increases. Some work has focused on masticatory behaviour as a form of daily health care that could help prevent cognitive impairment and dementia. However, it is not yet clear how masticatory behaviour influences various cognitive functions. Therefore, the purpose of this study was to examine the effect of masticatory behaviour on the decline of generalized attention, an important cognitive function. METHODS: Participants were 35 healthy, dentulous individuals without stomatognathic abnormalities (24 men, 11 women; mean age: 56.8 ± 4.8 years). All participants completed three interventions: mastication, foot-stepping, and none (control). Pre- and post-intervention measures of generalized attention were measured by using neuropsychological tests to examine general attention; the results were then compared. Simultaneously, during the generalized attention task, the functional activity of the prefrontal cortex was observed on functional near-infrared spectroscopy. RESULTS: Response time of generalized attention improved in both the masticatory and foot-stepping interventions. There was a transient increase in oxyhaemoglobin activity in the right and left prefrontal cortices in the masticatory intervention. CONCLUSIONS: Masticatory behaviour may be involved in a partial improvement of generalized attention and may induce prefrontal cortex activity in middle-aged and older adults.

Pilot study for hepatitis virus screening among employees as an effective approach to encourage employees who screened positive to receive medical care in Japan.

AIM: Countermeasures against hepatitis B and C virus (HBV, HCV) infection at work sites in Japan have not yet been implemented. This study aimed to determine the status of viral hepatitis infection among employees in Japan. METHODS: We undertook a workplace-based cross-sectional study from 2011 to 2016 in Hiroshima, Japan. Hepatitis B virus and HCV markers were identified during a routine checkup of employees in 15 enterprises. The screening results were sent to employees directly and not to employers. A thorough examination of the participants who screened positive was encouraged by forwarding to them a referral letter by our research group to specialized medical institutions. RESULTS: Of the 3015 employees, 2420 (80.3%) underwent hepatitis virus screening. Of these, 13.8% had been screened for hepatitis virus before this survey. The prevalence of hepatitis B surface antigen was 0.95% (n = 23; 95% confidence interval, 0.6-1.3%). The prevalence of hepatitis B core antibody was as high as 31.5% at age 60-69 years, and 41.5% at age 70 years and over. The HCV carrier rate was 0.45% (n = 11; 0.2-0.7%) and 54.5% of them had genotype 2. Thirty-four carriers were detected, and 44.1% of them were detected for the first time; 53.3% of the newly detected carriers visited medical institutions with the referral, and underwent a periodic follow-up or treatment. CONCLUSION: Promoting hepatitis virus screening for employees may help detect carriers who are unaware of their infection and require treatment. Submitting the results to employees with a referral letter to medical institutions at the time of positive diagnosis may be effective.

A seroepidemiological survey of the effect of hepatitis B vaccine and hepatitis B and C virus infections among elementary school students in Siem Reap province, Cambodia.

AIM: This study aimed to survey the prevalence and incidence of hepatitis B (HBV) and hepatitis C virus (HCV) infection among elementary school students in Siem Reap province, Cambodia and to evaluate the effects of a national infant HBV vaccination program introduced in 2001. METHODS: Students in 3rd grade during the 2011, 2012, and 2013 academic years were enrolled in this study; at the time of the second examination, in the 2014-2015 academic year, the students were in 5th or 6th grade. The incidence and prevalence rates of HBV and HCV infection were estimated and full HBV sequences were analyzed. RESULTS: Among 248 students (107 male and 141 female) born between 1999 and 2005, five students were HBV surface antigen (HBs-Ag) positive (2.02%), and all of them were infected with genotype C. Among them, subgenotype C1 was found in four students and, unexpectedly, complete genetic sequence identity of subgenotype C1 was found in two students from different families. The anti-HBV core (HBc) and anti-HBs prevalence rates were 10.89% and 16.13%, respectively. Twenty-five students were positive for anti-HBs and negative for both HBsAg and anti-HBc (10.08%; estimated serological vaccination rate); this rate increased significantly with the birth year (P = 0.0229). Prevalence of anti-HCV was 2.82%, and HCV RNA was not detected. The estimated incidence of HBV and HCV infection were both 0/1000 person-years (PY) (95% confidence interval, 0-20.61/1000 PY and 0-14.50/1000 PY, respectively). CONCLUSION: Hepatitis B virus full-genome sequencing and serological analysis revealed the possibility of horizontal transmission of HBV among Cambodian schoolchildren. However, the anti-HBc positivity rate decreased along with increasing age and estimated serological vaccination rates.

Incidence and risk factors of colorectal cancer based on 56 324 health checkups: A 7-year retrospective cohort study.

BACKGROUND AND AIM: Although mortality rates of colorectal cancer (CRC) have been increasing in Japan, its screening rates remain stagnant at 19.2% among Japanese population aged > 40 years in 2014. To evaluate the importance of CRC screening by fecal occult blood test (FOBT), this study estimated the incidence of FOBT-positivity and CRC by sex-age stratification and clarified the risk factors for CRC. METHODS: Between 2007 and 2014, 56 324 residents (21 517 men and 34 807 women) were enrolled in this study. The sex-age-stratified incidence rates of FOBT-positivity and CRC were estimated by records from health checkups and colonoscopy. Regarding CRC incidence rate in particular, positive predictive value was adopted to adjust bias of FOBT-positivity that did not undergo colonoscopy by person-year method. To investigate the risks of CRC onset, a nested case-control study with 1:10 person-matching on sex and age was performed. RESULTS: Incidence rates of FOBT-positivity and CRC are 4183/100 000 person-year (100 Kpy) and 141.3/100 Kpy, respectively. In both cases, men has higher incidence rate than women (1.3 times for FOBT; 4977 vs 3718/100 Kpy and 2.3 times for CRC; 217.0 vs 96.4/100 Kpy). CONCLUSIONS: The records from health checkups were useful to estimate incidence rates of CRC with this procedure. The age-stratified incidence rate indicated the importance of CRC screening by FOBT, especially for men and those aged > 50 years. Additionally, it is strongly recommended to do further investigation if positive for initial FOBT screening especially for those who are > 70 years.

Reduced prevalence of hepatitis B surface antigen positivity among pregnant women born after the national implementation of immunoprophylaxis for babies born to hepatitis B virus-carrier mothers in Japan.

AIM: We aimed to estimate hepatitis B surface antigen (HBsAg) positivity among birth year-stratified pregnant women in Hiroshima, Japan, and compare prevalence rates between women born before and after implementation of a national immunoprophylactic vaccination program for babies born to hepatitis B virus (HBV) carrier mothers in Japan. METHODS: Pregnant women who gave birth at all delivery hospitals/clinics in Hiroshima prefecture between 1 April 2010 and 31 March 2011 were eligible. Lists collected from each institution included survey items such as age (pregnant woman's birth year) and HBsAg and hepatitis C virus (HCV) antibody (anti-HCV) test results, which were posted anonymously and non-consolidated from medical records. We calculated the HBsAg and anti-HCV prevalence in our cohort according to the mothers' birth year. RESULTS: In 41 of 58 hospitals/clinics, 15 233 and 15 035 pregnant women underwent HBsAg and anti-HCV testing, corresponding to 59.6% and 58.9% of 25 546 births in the 2010 fiscal year, respectively. The overall HBsAg positive rate was 0.51% (95% confidence interval [CI], 0.40-0.63%), and an extremely low prevalence (0.10%; 95% CI, 0.00-0.25%) was observed among pregnant women born after 1986. However, the prevalence in this study was slightly higher than the nationwide value (0.31%) and the Chugoku region-specific value (0.46%) among first-time blood donors at Japanese Red Cross blood centers between 2001 and 2006. No significant difference in anti-HCV positivity was observed. CONCLUSION: Only two pregnant women born after the preventive program implementation were HBsAg-positive. Perinatal HBV transmission is estimated to be almost completely inhibited in the next generation.

Despite low viral titer in saliva samples, Sanger-based SARS-CoV-2 spike gene sequencing is highly applicable for the variant identification.

BACKGROUND: This study aimed to compare the performance of Sanger-based SARS-CoV-2 spike gene sequencing and Next Generation Sequencing (NGS)-based full-genome sequencing for variant identification in saliva samples with low viral titer. METHODS: Using 241 stocked saliva samples collected from confirmed COVID-19 patients between November 2020 and March 2022 in Hiroshima, SARS-CoV-2 spike gene sequencing (nt22735-nt23532) was performed by nested RT-PCR and Sanger platform using in-house primers. The same samples underwent full-genome sequencing by NGS using Illumina NextSeq2000. RESULTS: Among 241 samples, 147 were amplified by both the Sanger and the Illumina NextSeq2000 NGS, 86 by Sanger only, and 8 were not amplified at all. The overall amplification rates of Illumina NextSeq2000 NGS and Sanger were 61% and 96.7%, respectively. At low viral titer (< 103 copies/mL), Illumina NextSeq2000 NGS provided 19.2% amplification, while Sanger was 89.7% (p < 0.0001). Both platforms identified 38 wild type, 54 Alpha variants, 84 Delta variants, and 57 Omicron variants. CONCLUSIONS: Our study provided evidence to expand the capacity of Sanger-based SARS-CoV-2 spike gene sequencing for variants identification over full-genome by Illumina NextSeq2000 NGS for mass screening. Therefore, the feasible and simple Sanger-based SARS-CoV-2 spike gene sequencing is practical for the initial variants screening, which might reduce the gap between the rapid evolution of SARS-CoV-2 and its molecular surveillance.

Intermediate hepatitis B virus infection prevalence among 1622 pregnant women in rural Burkina Faso and implications for mother-to-child transmission.

In highly endemic countries for hepatitis B virus (HBV) infection, childhood infection, including mother-to-child transmission (MTCT), represents the primary transmission route. High maternal DNA level (viral load ≥ 200,000 IU/mL) is a significant factor for MTCT. We investigated the prevalence of HBsAg, HBeAg, and high HBV DNA among pregnant women in three hospitals in Burkina Faso and assessed the performance of HBeAg to predict high viral load. Consenting pregnant women were interviewed on their sociodemographic characteristics and tested for HBsAg by a rapid diagnostic test, and dried blood spot (DBS) samples were collected for laboratory analyses. Of the 1622 participants, HBsAg prevalence was 6.5% (95% CI, 5.4-7.8%). Among 102 HBsAg-positive pregnant women in DBS samples, HBeAg was positive in 22.6% (95% CI, 14.9-31.9%), and viral load was quantified in 94 cases, with 19.1% having HBV DNA ≥ 200,000 IU/mL. HBV genotypes were identified in 63 samples and predominant genotypes were E (58.7%) and A (36.5%). The sensitivity of HBeAg by using DBS samples to identify high viral load in the 94 cases was 55.6%, and the specificity was 86.8%. These findings highlight the need to implement routine HBV screening and effective MTCT risk assessment for all pregnant women in Burkina Faso to enable early interventions that can effectively reduce MTCT.

Prevalence and genotype distribution of viral hepatitis B in Cambodia between 1990 and 2020: a systematic review and meta-analysis.

BACKGROUND: Hepatitis B virus (HBV) infection is one of the major public health problems globally as well as in Cambodia. Continuous information on HBV infection burden is required to implement effective disease control strategies. This study aimed to determine the prevalence and genotype distribution of HBV infection in Cambodia through a systematic review with meta-analysis. METHODS: Four databases (PubMed, Web of Science, Scopus, and Google Scholar) were used to search published studies reporting either HBV prevalence or genotype distribution in Cambodia until August 21, 2020. Reviews, modeling studies, and studies conducted among Cambodian permanently living abroad were excluded. The Freeman-Tukey double arcsine transformation was implemented to achieve approximate normality. The DerSimonian and Laird method was used to compute pooled estimates based on the transformed values and their variance. Possible publication bias was assessed by the Egger test and the funnel plot. RESULTS: A total of 22 studies were included, covering 22,323 people. Ten studies reported HBV prevalence in the general population. The HBV infection prevalence was 4.73% (95%CI: 2.75-7.17%) in the general population and 19.87% (95%CI: 10.95-30.63%) in high-risk/co-infected groups. By sub-group analysis, the prevalence was 6.81% (95% CI: 4.43-9.66) in adults older than 15 years old, 2.37% (95% CI:0.04-7.05) in children 6-15 years old, and 2.47% (95% CI: 0.96-4.59) in children less than five years old. The prevalence of HBV infection decreased over time. Predominant HBV genotypes were genotypes C and B with 82.96% and 16.79%, respectively. CONCLUSIONS: The decrease in HBV infection prevalence in Cambodia demonstrates the effects of national hepatitis B immunization, improved clinical hygiene, and the use of disposable devices. However, the estimated HBV prevalence among the general population indicates an intermediate endemicity level of HBV infection. Therefore, population screening and linkage to care, high vaccination coverage, health promotion, and HBV surveillance are essential to meet the WHO 2030 goal.

Patient satisfaction with conventional dentures vs. digital dentures fabricated using 3D-printing: A randomized crossover trial.

PURPOSE: Evidence regarding the performance of digital dentures (DDs) fabricated using 3D printing is insufficient. This study aimed to evaluate patient satisfaction with conventional dentures (CDs) and DDs fabricated using 3D printing. METHODS: This randomized controlled trial was conducted between November 2017 and May 2020. In the CD-DD group, CDs were fabricated before DDs, while the protocol was reversed in the DD-CD group. The primary outcome was patient satisfaction, quantified using a 100-mm visual analog scale, which assessed chewing efficiency, pain, stability, retention, comfort, esthetics, ease of cleaning, phonetics, and general satisfaction. Secondary outcomes were quality of life (QOL), number of visits, time required for definitive denture fabrication, number of adjustment appointments, and time required for denture stabilization after denture delivery. RESULTS: Patient satisfaction with CDs was superior in terms of phonetics, ease of cleaning, stability, comfort, and general satisfaction. Secondary outcomes such as social disability and the number of clinic visits were significantly lower in patients with DDs. However, the two groups showed no significant differences in the other outcomes. Although patient satisfaction with DDs was inferior to that with CDs, 20% of patients preferred and used DDs (12 patients preferred CDs, and three patients opted for DDs). CONCLUSION: Although patient satisfaction or QOL with DDs may be somewhat inferior to that with CDs, 20% of patients preferred and used DDs daily. Thus, DDs fabricated using 3D printing may have comparable practicality and efficacy to CDs.

Exercising the Sanger Sequencing Strategy for Variants Screening and Full-Length Genome of SARS-CoV-2 Virus during Alpha, Delta, and Omicron Outbreaks in Hiroshima.

This study aimed to exercise the Sanger sequencing strategy for screening of variants among confirmed COVID-19 cases and validate our strategy against NGS strains in Hiroshima retrieved from GISAID. A total of 660 samples from confirmed COVID-19 cases underwent screening for variants by Sanger-based partial sequencing to the targeted spike gene (nt22,735~nt23,532) using an in-house-developed primer set. The identification of variants was done by unique checkpoints of base nucleotide changes in the targeted spike gene. Moreover, we amplified one full-length genome using Sanger method and an in-house-developed primer library. Using NGS strains of the same sampling period from GISAID, a phylogenetic tree was constructed to examine the distribution pattern of variants in Hiroshima and to validate our Sanger method. The modified primer set provided 100% validation and 99.2% amplification. PANGO Lineage R.1 was detected in late in the third wave, followed by Alpha (B.1.1.7) domination in the fourth wave, Delta (B.1.617.2) domination in the fifth wave, and Omicron (B.1.1.529) domination in the sixth wave, and there was no significant difference in viral copies between variants (p = 0.09). The variants showed different transmission patterns, but the distribution of variants is consistent to that shown by the phylogenetic tree. The Sanger method also provided successful amplification of the full-length genome of the SARS-CoV-2 virus. Our Sanger sequencing strategy was useful for the screening of SASR-CoV-2 variants without the need for full-genome amplification. The modified primer set was validated to use universally, which allows an understanding of the variants' distribution in real time and provides the evidence for policy-making and the formulation or modification of preventive strategies.