The impact of COVID-19 on hepatitis B and C virus prevention, diagnosis, and treatment in Bangladesh compared with Japan and the global perspective

AIM

This study aimed to assess the effect of COVID-19 on hepatitis-related services in Bangladesh and compared the situation with same study conducted in Japan and globally.

METHODS

We conducted an online cross-sectional questionnaire survey among the clinicians of four societies associated with liver disease in Bangladesh from October to December 2022. The questionnaire included the same questions as a survey conducted in Japan and globally.

RESULTS

A total of 83 clinicians from 8 divisions in Bangladesh participated; 66.3% were heads of departments/institutions. Except for HCV treatment initiation, more than 30% of clinicians reported a 76-99% decline in all services. Compared to Japan and the global survey, there was a significantly higher decline in all HBV and HCV services in Bangladesh. To resume services back to pre-COVID-19 levels, Patient anxiety and fear (Bangladesh Survey: 80.7% vs Japan Survey: 67.4% vs Global Survey: 37.9%, p < 0.0001), loss of space due to COVID-19 (Bangladesh Survey: 63.9% vs Japan Survey: 34.7% vs Global Survey: 19.4%, p < 0.0001) were the main challenges. As part of the mitigation strategy, usage of telemedicine (Bangladesh Survey: 83.1% vs. Japan Survey: 67.3% vs Global Survey: 78.6% p < 0.0001), COVID-19 benefits, such as increased laboratory testing platforms (Bangladesh Survey: 77.1% vs Japan Survey: 17.9% vs Global Survey: 41.8%, p < 0.0001) was reported significantly higher in Bangladesh than in Japan and global survey.

CONCLUSION

All the services-related to HBV and HCV were highly affected during greatest impact month of COVID-19 in Bangladesh and the decline level was higher than Japan and global survey. Repeated countermeasures of COVID-19 and constrained healthcare-system were the probable reasons in Bangladesh. Positive impact resulting from COVID-19 countermeasures should be utilized in the national hepatitis program in Bangladesh.

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.

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.

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 of fatty liver and advanced fibrosis by ultrasonography and FibroScan in a general population random sample

AIM

Fatty liver is the most common liver disease. This study examined fatty liver and advanced fibrosis prevalence in a random sample of the Japanese general population.

METHODS

A total of 6000 people randomly selected from two cities in Hiroshima Prefecture were invited to participate in this cross-sectional study originally carried out for hepatitis virus screening. Ultrasonography and FibroScan (controlled attenuation parameter [CAP] and liver stiffness measurement [LSM]) were provided as additional tests.

RESULTS

Of 6000 invited individuals, 1043 participated in hepatitis virus screening, of which 488 randomly selected individuals (median age, 56 years; interquartile range, 45-68 years; male participants, 49.8%) underwent ultrasonography, CAP, and LSM. Ultrasonography showed fatty liver in 24.6% and mild fatty liver in 32.8%. Controlled attenuation parameter showed severe steatosis in 27.5%, moderate steatosis in 12.5%, and mild steatosis in 11.1%. Overall, 62.1% were diagnosed with fatty liver based on ultrasonography or CAP. Nonalcoholic fatty liver disease (NAFLD) prevalence was 50.6%. Liver stiffness measurement found cirrhosis in 1.0% and severe fibrosis in 1.8%. Multivariate analysis of risk factors associated with ≥F2 or higher liver fibrosis showed that age ≥60 years and above (adjusted odds ratio [AOR], 3.2; 95% confidence interval [CI], 1.5-6.9; p = 0.0031), hepatitis C virus antibody positivity (AOR, 8.4; 95% CI, 1.0-68.4; p = 0.0467), and fatty liver (AOR, 2.3; 95% CI, 1.1-6.2; p = 0.0317) are independent risk factors.

CONCLUSIONS

In the general population, 62.1% had fatty liver, and NAFLD prevalence was twice as high as previously reported. Screening that is noninvasive, low-cost, and does not require special techniques or equipment is needed to detect advanced liver fibrosis.

Seroepidemiological study of factors affecting anti-spike IgG antibody titers after a two-dose mRNA COVID-19 vaccination in 3744 healthy Japanese volunteers

Several factors related to anti-spike(S) IgG antibody titers after mRNA COVID-19 vaccination have been elucidated, but the magnitude of the effects of each factor has not been fully understood. This cross-sectional study assessed anti-S and anti-nucleocapsid (N) antibody titers on 3744 healthy volunteers (median age, 36 years; IQR, 24-49 years; females, 59.0%) who received two doses of mRNA-1273 or BNT162b2 vaccine and completed a survey questionnaire. Multiple regression was conducted to identify factors associated with antibody titers. All but one participant tested positive for anti-S antibodies (99.97%). The following factors were independently and significantly associated with high antibody titer: < 3 months from vaccination (ratio of means 4.41); mRNA-1273 vaccine (1.90, vs BNT162b2); anti-N antibody positivity (1.62); age (10's: 1.50, 20's: 1.37, 30's: 1.26, 40's: 1.16, 50's: 1.15, vs ≧60's); female (1.07); immunosuppressive therapy (0.54); current smoking (0.85); and current drinking (0.96). The largest impact on anti-S IgG antibody titers was found in elapsed time after vaccination, followed by vaccine brand, immunosuppressants, previous SARS-CoV-2 infection (anti-N antibody positive), and age. Although the influence of adverse reactions after the vaccine, gender, smoking, and drinking was relatively small, they were independently related factors.

Prevalence of Helicobacter pylori infection in the general population evaluated by a resident-register-based epidemiological study

BACKGROUND

The current status of Helicobacter pylori infection in Japan has not been investigated. We evaluated the status of H. pylori infection in a Japanese general population using large-scale resident-register-based sampling.

METHODS

All 6069 adults in a rural town and 6000 adults in two urban cities (3000 each), selected by register-based random sampling, were enrolled in our health check-up program. Antibody titers against Helicobacter pylori (cut-off value was 3 U/mL by Eiken E-plate) were evaluated, and subjects with a positive result were encouraged to undergo further examinations.

RESULTS

A total of 1586 subjects participated in serum sampling. The overall prevalence of H. pylori infection was 40.0% (634/1586), and it increased with age both in rural and urban areas. Although the overall positive rate was higher in the rural area (49.4%) than in the urban areas (35.6 and 32.3%), there was no difference in H. pylori status of younger subjects between the two areas. Among 634 patients with a positive titer, 374 (59.0%) underwent further examinations including endoscopic examination, and 180/634 (28.4%) patients received eradication therapy. Gastric neoplasms (three adenocarcinomas and one adenoma) were found in our screening program.

CONCLUSION

We clarified population-based random sampling data of H. pylori infection in a Japanese general population. In younger subjects, a decrease in the prevalence of H. pylori infection was confirmed both in rural and urban areas. This provides basic information for establishing a strategy to reduce gastric cancer deaths.

Prevalence and risk factors of malaria among first antenatal care attendees in rural Burkina Faso

BACKGROUND

The WHO recommends continuous surveillance of malaria in endemic countries to identify areas and populations most in need for targeted interventions. The aim of this study was to assess the prevalence of malaria and its associated factors among first antenatal care (ANC) attendees in rural Burkina Faso.

METHODS

A cross-sectional survey was conducted between August 2019 and September 2020 at the Yako health district and included 1067 first ANC attendees. Sociodemographic, gyneco-obstetric, and medical characteristics were collected. Malaria was diagnosed by standard microscopy and hemoglobin level was measured by spectrophotometry. A multivariate logistic regression analysis was used to identify factors associated with malaria infection.

RESULTS

Overall malaria infection prevalence was 16.1% (167/1039). Among malaria-positive women, the geometric mean parasite density was 1204 [95% confidence interval (CI) 934-1552] parasites/µL and the proportion of very low (1-199 parasites/µL), low (200-999 parasites/µL), medium (1000-9999 parasites/µL) and high (≥ 10,000 parasites/µL) parasite densities were 15.0%, 35.3%, 38.3% and 11.4%, respectively. Age < 20 years (adjusted odds ratio (aOR): 2.2; 95% CI 1.4-3.5), anemia (hemoglobin < 11 g/deciliter) (aOR: 3.4; 95% CI 2.2-5.5), the non-use of bed net (aOR: 1.8; 95% CI 1.1-2.8), and the absence of intermittent preventive treatment with sulfadoxine-pyrimethamine (aOR: 5.8; 95% CI 2.1-24.5) were positively associated with malaria infection.

CONCLUSIONS

The study showed that one out of six pregnant women had a microscopy-detected P. falciparum malaria infection at their first ANC visit. Strengthening malaria prevention strategies during the first ANC visit is needed to prevent unfavorable birth outcomes.

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.

Distribution of FIB-4 index in the general population: analysis of 75,666 residents who underwent health checkups

Background

Fatty liver is frequently found in a general population, and it is critical to detect advanced fibrosis. FIB-4 index is considered a useful marker for evaluating liver fibrosis but the distribution of FIB-4 index in the general population remains unknown.

Methods

This cross-sectional study included residents who underwent ultrasonography at health checkups in Hiroshima or Iwate prefectures. The distribution of FIB-4 index in the total study population (N = 75,666) as well as in non-alcoholic fatty liver disease (NAFLD) populations (N = 17,968) and non-drinkers without fatty liver populations (N = 47,222) was evaluated. The distribution of aspartate aminotransferase (AST) levels, alanine aminotransferase (ALT) levels was also evaluated.

Results

The mean FIB-4 index in the total study population was 1.20 ± 0.63. FIB-4 index ≥ 2.67, which indicates a high risk of liver fibrosis, was found in 16.4% of those aged ≥ 70 years. In the NAFLD population, 58.1% of those in their 60 s and 88.1% of those ≥ 70 years met the criteria for referral to hepatologists by using the recommended FIB-4 index cutoff value (≥ 1.3). The mean FIB-4 index in the NAFLD population (1.12 ± 0.58) was significantly lower than in the non-drinkers without fatty liver (1.23 ± 0.63, p < 0.0001). The non-drinkers without fatty liver tended to have higher AST relative to ALT levels (60.0% with AST/ALT > 1.0), whereas the results in the NAFLD population were opposite (14.8% with AST/ALT > 1.0). AST > ALT resulted in a higher FIB-4 index in non-drinkers without fatty liver due to the nature of FIB-4 index formula.

Conclusions

The cutoff value of FIB-4 index (≥ 1.3) for triaging the elderly people with fatty liver for referral to hepatologists should be reconsidered to avoid over-referral. Due to the impact of age and characteristics of AST/ALT ratios, there is no prospect of using FIB-4 index for primary screening for liver fibrosis in a general population of unknown presence or absence of liver disease, even though it can be easily calculated using routine clinical indices. It is desired to develop a non-invasive method for picking up cases with advanced fibrosis latent in the general population.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02290-1.

Long COVID occurrence in COVID-19 survivors

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.

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.

Low birth weight and its associated risk factors in a rural health district of Burkina Faso: a cross sectional study

Background

Low birth weight (LBW) is a major factor of neonate mortality that particularly affects developing countries. However, the scarcity of data to support decision making to reduce LBW occurrence is a major obstacle in sub-Saharan Africa. The aim of this research was to determine the prevalence and associated factors of LBW at the Yako health district in a rural area of Burkina Faso.

Methods

A cross sectional survey was conducted at four peripheral health centers among mothers and their newly delivered babies. The mothers’ socio-demographic and obstetrical characteristics were collected by face-to-face interview or by review of antenatal care books. Maternal malaria was tested by standard microscopy and neonates’ birth weights were documented. Multivariate logistic regression was used to determine factors associated with LBW. A p-value < 0.05 was considered statistically significant.

Results

Of 600 neonates examined, the prevalence of low birth weight was 11.0%. Adjustment for socio-demographic characteristic, medical conditions, obstetrical history, malaria prevention measures by multivariate logistic regression found that being a primigravid mother (aOR = 1.8, [95% CI: 1.1–3.0]), the presence of malaria infection (aOR = 1.9, [95% CI: 1.1–3.5]), the uptake of less than three doses of sulfadoxine-pyrimethamine for the intermittent preventive treatment of malaria in pregnancy (IPTp-SP) (aOR = 2.2, [95% CI: 1.3–3.9]), the presence of maternal fever at the time of delivery (aOR = 2.8, [95% CI: 1.5–5.3]) and being a female neonate (aOR = 1.9, [95% CI: 1.1–3.3]) were independently associated with an increased risk of LBW occurrence. The number of antenatal visits performed by the mother during her pregnancy did not provide any direct protection for low birth weight.

Conclusion

The prevalence of LBW remained high in the study area. Maternal malaria, fever and low uptake of sulfadoxine-pyrimethamine doses were significantly associated with LBW and should be adequately addressed by public health interventions.

Burden of chronic hepatitis B and C infections in 2015 and future trends in Japan: A simulation study

Background

Determining the number of chronic hepatitis B (HBV) and C virus (HCV) infections is essential to assess the progress towards the World Health Organization 2030 viral hepatitis elimination goals. Using data from the Japanese National Database (NDB), we calculated the number of chronic HBV and HCV infections in 2015 and predicted the trend until 2035.

Methods

NDB and first-time blood donors data were used to calculate the number of chronic HBV and HCV infections in 2015. A Markov simulation was applied to predict chronic infections until 2035 using transition probabilities calculated from NDB data.

Findings

The total number of chronic HBV and HCV infections in 2015 in Japan was 1,905,187–2,490,873 (HCV:877,841–1,302,179, HBV:1,027,346–1,188,694), of which 923,661–1,509,347 were undiagnosed or diagnosed but not linked to care (“not engaged in care”), and 981,526 were engaged in care. Chronic HBV and HCV infections are expected to be 923,313–1,304,598 in 2030, and 739,118–1,045,884 in 2035. Compared to 2015, by 2035, the number of persons with HCV not engaged in care will decline by 59·8 – 76·1% and 86·5% for patients in care. For HBV, a 47·3 – 49·3% decrease is expected for persons not engaged in care and a decline of 26·0% for patients engaged in care.

Interpretation

Although the burden of HBV and HCV is expected to decrease by 2035, challenges in controlling hepatitis remain. Improved and innovative screening strategies with linkage to care for HCV cases, and a functional cure for HBV are needed.

Funding

Japan Ministry of Health, Labour and Welfare.

Mass Screening of SARS-CoV-2 Variants using Sanger Sequencing Strategy in Hiroshima, Japan

This study aimed to develop the feasible and effective universal screening strategy of the notable SARS-CoV-2 variants by Sanger Sequencing Strategy and then practically applied it for mass screening in Hiroshima, Japan. A total of 734 samples from COVID-19 confirmed cases in Hiroshima were screened for the notable SARS-CoV-2 variants (B.1.1.7, B.1.351, P.1, B.1.617.2, B.1.617.1, C.37, B.1.1.529, etc.). The targeted spike region is amplified by nested RT-PCR using in-house designed primer set hCoV-Spike-A and standard amplification protocol. Additionally, randomly selected 96 samples were also amplified using primer sets hCoV-Spike-B and hCoV-Spike-C. The negative amplified samples were repeated for second attempt of amplification by volume-up protocol. Thereafter, the amplified products were assigned for Sanger sequencing using corresponding primers. The positive amplification rate of primer set hCoV-Spike-A, hCoV-Spike-B and hCoV-Spike-C were 87.3%, 83.3% and 93.8% respectively for standard protocol and increased to 99.6%, 95.8% and 96.9% after second attempt by volume-up protocol. The readiness of genome sequences was 96.9%, 100% and 100% respectively. Among 48 mutant isolates, 26 were B.1.1.7 (Alpha), 7 were E484K single mutation and the rest were other types of mutation. Moreover, 5 cluster cases with single mutation at N501S were firstly reported in Hiroshima. This study indicates the reliability and effectiveness of Sanger sequencing to screen large number of samples for the notable SARS-CoV-2 variants. Compared to the Next Generation Sequencing (NGS), our method introduces the feasible, universally applicable, and practically useful tool for identification of the emerging variants with less expensive and time consuming especially in those countries where the NGS is not practically available. Our method allows not only to identify the pre-existing variants but also to examine other rare type of mutation or newly emerged variants and is crucial for prevention and control of pandemic.

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.

Relationship between drinking frequency and fatty liver prevalence or incidence in Japanese undergoing health checkup in 2008-2019

BACKGROUND & AIMS

The relationship between the frequency of drinking and fatty liver in the general population is still poorly understood. This study analysed data from a large cohort who underwent health checkups in Japan between 2008 and 2019 to investigate the prevalence and incidence of fatty liver by alcohol consumption and risk factors for fatty liver.

METHODS

The prevalence of fatty liver diagnosed with ultrasonography was calculated in 75,670 residents. The incidence of fatty liver in 31,062 residents who underwent ultrasonography at least twice during the period without fatty liver at the first time was calculated using the person-year method. Multivariate logistic analysis was performed to investigate risk factors associated with the prevalence and incidence of fatty liver.

RESULTS

The prevalence of fatty liver was 27.6% (95% confidence interval [CI], 27.2-27.9) in non-drinkers, 28.5% (27.5-29.5) in moderate-drinkers and 28.0% (26.0-29.9) in heavy-drinkers. The incidence of fatty liver was 3,084/100,000 person-years (2,997-3,172/100,000) in non-drinkers, 3,754/100,000 person-years (3,481-4,042/100,000) in moderate-drinkers and 3,861/100,000 person-years (3,295-4,497/100,000) in heavy-drinkers. The prevalence and incidence of fatty liver were not associated with drinking status. Obesity was the most important independent risk factor (prevalence: adjusted odds ratio [AOR], 6.3; 95% CI, 6.0-6.5; incidence: AOR, 2.4; 95% CI, 2.3-2.6).

CONCLUSIONS

Drinking status does not affect the prevalence or incidence of fatty liver in Japanese residents undergoing health checkups. From a public health perspective, measures for obesity control must be prioritised to reduce the burden of disease of fatty liver in Japan.

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.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-06817-x.

Molecular characterization and the mutation pattern of SARS-CoV-2 during first and second wave outbreaks in Hiroshima, Japan

BACKGROUND

In this study, we performed molecular characterization of SARS-CoV-2 strains in Hiroshima and its mutation pattern between the first and second waves of the outbreak.

METHOD

A total of 55 nasal swab samples from the first wave in Hiroshima and 13 from the second wave were examined quantitatively by RT-qPCR and qualitatively by nested PCR using specific primers. Four samples from each wave underwent next-generation sequencing and phylogenetic tree analysis including controls and all sequences retrieved in Japan from GISAID and GenBank. Subsequently, mutations were examined.

RESULTS

Viral load ranged 7.85 × 101-1.42 × 108 copies/ml. Of 68 samples, one was Asian type-O, 65 were European type-GR, and 2 were undetectable. Phylogenetic tree analysis indicated that Japan was infected with various Asian strains (L, S, V, O) from January through April. By second week of March, European strains (G, GH, GR) had appeared, and GR strains became predominant after mid-March. The first case in Hiroshima was classified as Asian strain O, and the rest were GR strains. Then, second wave of GR strains appeared independently with 11-15 base mutations. Comparing the first- and second-wave GR strains, mutation rate was 1.17-1.36 × 10-3 base substitutions per site per year; in addition, amino acid changes occurred at S1361P and P3371S in ORF1a, A314V in ORF1b, and P151L in N. All seven GR strains were D614G variants with R202K and G203R mutations in N. A single-nucleotide insertion in ORF8 that causes a defect in ORF8 protein was found in one isolate (S66) from the second wave.

CONCLUSION

Our findings reveal the evolutionary hierarchy of SARS-CoV-2 in Japan. The predominant D614G variants and a new form of ORF8 deletion in Hiroshima provide the clue for role of viral factor in local outbreaks of SARS-CoV-2.

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.

[Varicella (chickenpox) morbidity and mortality in hospital: about 19 cases collected at the Yalgado Ouedraogo University Hospital, Burkina Faso]

La varicelle est une virose dont l'épidémiologie est mal connue au Burkina Faso. Cette étude s'est donnée pour objectif de décrire le profil hospitalier de la pathologie dans le service des maladies infectieuses du Centre Hospitalier Universitaire Yalgado Ouedraogo (CHU-YO). Il s'est agi d'une série de 19 patients hospitalisés entre le 1^er janvier 2005 et le 31 décembre 2014. Ont été inclus, tous les patients avec un dossier complet et exploitable, dont le diagnostic positif de varicelle a été fait. La proportion périodique de varicelle était de 6,2% et a représenté 14,6% des éruptions fébriles. Elle était plus fréquente en 2011, de janvier à mars. L'âge médian était de 19 ans, et la moitié des patients avaient entre 6 et 30 ans. Les comorbidités étaient dominées par l'infection à VIH et l'herpès. Sur le plan clinique, la fièvre et le prurit étaient les symptômes communs et la vésicule la principale éruption. A l'admission, les principales complications étaient pulmonaires, hématologiques et cutanées. La durée médiane d'hospitalisation était de 5 jours, avec des extrêmes de 0 et 13 jours. Les principaux traitements étaient antiviral dans 9 cas, antipyrétique dans 19 cas, local dans 17 cas et antihistaminique dans 11 cas. Sur 19 cas de varicelle, 14 ont guéri et deux sont décédés, dont un adulte sur 10 et 1 enfant sur 9. Si la varicelle est une affection habituellement bénigne, elle peut être fatale chez l'adulte et l'enfant en cas de complications graves.

African isolates show a high proportion of multiple copies of the Plasmodium falciparum plasmepsin-2 gene, a piperaquine resistance marker

BACKGROUND

Today, the development of new and well-tolerated anti-malarial drugs is strongly justified by the emergence of Plasmodium falciparum resistance. In 2014-2015, a phase 2b clinical study was conducted to evaluate the efficacy of a single oral dose of Artefenomel (OZ439)-piperaquine (PPQ) in Asian and African patients presenting with uncomplicated falciparum malaria.

METHODS

Blood samples collected before treatment offered the opportunity to investigate the proportion of multidrug resistant parasite genotypes, including P. falciparum kelch13 mutations and copy number variation of both P. falciparum plasmepsin 2 (Pfpm2) and P. falciparum multidrug resistance 1 (Pfmdr1) genes.

RESULTS

Validated kelch13 resistance mutations including C580Y, I543T, P553L and V568G were only detected in parasites from Vietnamese patients. In Africa, isolates with multiple copies of the Pfmdr1 gene were shown to be more frequent than previously reported (21.1%, range from 12.4% in Burkina Faso to 27.4% in Uganda). More strikingly, high proportions of isolates with multiple copies of the Pfpm2 gene, associated with piperaquine (PPQ) resistance, were frequently observed in the African sites, especially in Burkina Faso and Uganda (> 30%).

CONCLUSIONS

These findings were considered to sharply contrast with the recent description of increased sensitivity to PPQ of Ugandan parasite isolates. This emphasizes the necessity to investigate in vitro susceptibility profiles to PPQ of African isolates with multiple copies of the Pfpm2 gene and estimate the risk of development of PPQ resistance in Africa. Trial registration Clinicaltrials.gov reference: NCT02083380. Study title: Phase II efficacy study of artefenomel and piperaquine in adults and children with P. falciparum malaria. https://clinicaltrials.gov/ct2/results?cond=&term=NCT02083380&cntry=&state=&city=&dist= . FSFV: 23-Jul-2014; LSLV: 09-Oct-2015.

High prevalence of hepatitis B infections in Burkina Faso (1996-2017): a systematic review with meta-analysis of epidemiological studies

BACKGROUND

Hepatitis B virus (HBV) infection was long considered an important public health concern in Burkina Faso and still represents a major cause of liver cancer and cirrhosis in the active population. To counter the problem, a national strategic plan was developed and adopted in July 2017 to coordinate viral hepatitis elimination's efforts. However evidence to support its implementation remains scanty and scattered. The main purpose of this study was to summarize available information from per-reviewed articles published over the last two decades to accurately estimate the prevalence of HBV infection in Burkina Faso.

METHODS

We conducted a systematic search with meta-analysis of scientific articles using Science-Direct, Web-of-Science, PubMed/Medline, and Google Scholar. We systematically assessed all relevant publications that measured the prevalence of hepatitis B surface antigen and which were published between 1996 and 2017. We estimated the national HBV prevalence and its 95% confident interval. We subsequently adjusted the meta-analysis to possible sources of heterogeneity.

RESULTS

We retrieved and analyzed a total of 22 full text papers including 99,672 participants. The overall prevalence was 11.21%. The prevalence after adjustment were 9.41%, 11.11%, 11.73% and 12.61% in the general population, pregnant women, blood donors and HIV-positive persons respectively. The prevalence was higher before implementation of HBV universal vaccination and decreased from 12.80% between 1996 and 2001 to 11.11% between 2012 and 2017. The prevalence was also higher in rural area 17.35% than urban area 11.11%. The western regions were more affected with 12.69% than the central regions 10.57%. The prevalence was 14.66% in the boucle of Mouhoun region and 14.59 in the center-west region. Aggregate data were not available for the other regions.

CONCLUSIONS

HBV has clearly an important burden in Burkina Faso as described by its high prevalence and this problem significantly challenges the national health care system. There is an urgent need for effective public health interventions to eliminate the problem. However, higher quality data are needed to produce reliable epidemiological estimates that will guide control efforts towards the achievement of the national strategic plan's goals.

Gender differences in sociodemographic and behavioural factors associated with BMI in an adult population in rural Burkina Faso - an AWI-Gen sub-study

BACKGROUND

The global health transition is linked with an increased burden of non-communicable diseases with cardiovascular diseases leading the epidemic. In sub-Saharan Africa (SSA), the prevalence of obesity has increased during the past decades and there is a need to investigate the associated driving factors. In Burkina Faso obesity remains low, especially in rural areas. In this study we recruited middle-aged adults, as part of a larger study on genetic and environmental contributions to cardiometabolic disease among Africans.

OBJECTIVES

To investigate the distribution of BMI and prevalence of obesity in a cross-sectional population-based study and to determine the sociodemographic and behavioural correlates with BMI.

METHODS

Participants (N = 2,076) were recruited from the Nanoro Health and Demographic Surveillance System area and were aged 40-60 years. We applied hierarchical modelling to identify factors associated with BMI and structural equation modelling to identify mediated effects of sociodemographic and behavioural variables on BMI.

RESULTS

Data are presented on 2,076 participants (49.9% female). Men had significantly higher BMI than women with medians of 21.1 (19.2 - 23.4) vs 19.8 (18.1 - 21.6) (p < 0.001), and there were significantly more underweight women compared to men (31.0% vs 17.4%) (p < 0.001). More men were overweight and obese than women (11.9% vs 5.2% and 2.2% vs 1.4%). Socioeconomic status was the major contributor to increased BMI for men, and education was the main contributor in women. Tobacco smoking and chewing, and problematic alcohol consumption were associated with a decrease in BMI in men and women.

CONCLUSION

Overweight and obesity are relatively low among adults in rural Burkina Faso, and men had a higher median BMI than women. Behavioural factors, including tobacco use and alcohol consumption, contributed to a decrease in BMI, whereas socioeconomic status and education (which were both generally low in this community) contributed to an increase in BMI.