Epidemiology and Health

Brief communications

Prevalence of SARS-CoV-2 infection among urban cleaning and solid waste management workers during transmission of the Omicron variant in Brazil: Paulo Ricardo Martins-Filho, Joyce Thayane da Conceição dos Santos, Márcia Santos Rezende, Fernanda Oliveira de Carvalho, Érica Santos dos Reis, Waneska de Souza Barboza, Taise Ferreira Cavalcante, Cliomar Alves dos Santos, Lucindo José Quintans-Júnior, Renata Grespan, Cristiane Bani Corrêa, Tatiana Rodrigues de Moura, Dulce Marta Schimieguel, Jullyana de Souza Siqueira Quintans, Adriano Antunes de Souza Araújo; Epidemiol Health. 2022;e2023025. Published online February 16, 2023; DOI: https://doi.org/10.4178/epih.e2023025 [Accepted]

287 View
62 Download

Abstract PDF: Abstract
This study estimated the prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in urban cleaning and solid waste management workers during the transmission of the Omicron variant in one of the poorest regions of Brazil (the state of Sergipe). Nasopharyngeal swabs were collected from 494 workers, and the presence of SARS-CoV-2 RNA was tested by quantitative reverse-transcriptase polymerase chain reaction. Data on sociodemographic characteristics, comorbidities, vaccination status, mask use, and use of public transport to commute to the workplace were collected. The prevalence with a 95% confidence interval (CI) was calculated from the proportion of SARS-CoV-2 positive cases among the total number of individuals tested. The prevalence ratio (PR) with a 95% CI was the measure of association used to evaluate the relationship between SARS-CoV-2 infection and the exposure variables. The prevalence of SARS-CoV-2 infection was 22.5% (95% CI, 19.0%–26.4%). Individuals under the age of 40 had a higher prevalence of infection (PR=1.53; 95% CI, 1.03–2.30) as well as those who did not believe in the protective effect of vaccines (PR=1.78; 95% CI, 1.05–2.89). Our results indicate the need for better guidance on preventive measures against COVID-19 among urban cleaning and solid waste management workers.; Summary

Korean summary

Key Message

Prevalence and methodological quality of systematic reviews in Korean medical journals: Seong Jung Kim, Mi Ah Han, Jae Hung Jung, Eu Chang Hwang, Hae Ran Kim, Sang-Eun Yoon, Seo-Hee Kim, Pius Kim, So-Yeong Kim; Epidemiol Health. 2022;e2023017. Published online February 6, 2023; DOI: https://doi.org/10.4178/epih.e2023017 [Accepted]

229 View
18 Download

Abstract PDF: Abstract
This study aimed to assess and evaluate the prevalence and methodological quality of systematic reviews (SRs) published in major Korean medical journals (KMJs). The top 15 journals with the highest Korean Medical Citation Index, published between 2018 to 2021, were selected. We assessed the methodological quality of SRs using A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR 2). In total, 126 SRs were included, with an average of 32 SRs being reported annually. The overall prevalence of SRs in KMJs was 2.8%, with an increase from 2.6% in 2018 to 3.4% in 2021. Overall, the methodological quality of SRs was low (9.5% low, 90.5% critically low). More than 80% of the studies adhered to critical domain items such as a comprehensive literature search and risk of bias assessment, but for items such as protocol registration and listing excluded studies and the justification for exclusion, the adherence rate was less than 15%. While the number of SRs in KMJs steadily increased, the overall confidence in the methodological quality was low to critically low. Therefore, in order to provide the best evidence for decision-making in clinical and public health areas, editors, reviewers, and authors need to pay more attention to improving the quality of SRs.; Summary

Korean summary

Key Message

Self-reported Adverse events following the second dose of COVID-19 Vaccines in the Republic of Korea: Recipient survey, February to December 2021: Yunhyung Kwon, Insob Hwang, Mijeong Ko, Hyungjun Kim, Seontae Kim, Soon-Young Seo, Enhi Cho, Lee Yeon-Kyeng; Epidemiol Health. 2022;e2023006. Published online December 26, 2022; DOI: https://doi.org/10.4178/epih.e2023006 [Accepted]

343 View
48 Download

Abstract PDF: Abstract
Objectives
The national coronavirus disease 2019(COVID-19) vaccination program was implemented with four vaccines against COVID-19 in the Republic of Korea. A text-based survey, in addition to a passive adverse event reporting system, was launched to report unusual symptoms after vaccination quickly. This study aims to compare the frequency of adverse events caused by COVID-19 vaccines based on the vaccine type and the homologous and heterologous 2-dose regimen.
Methods
The self-reported adverse symptoms of vaccination were collected through a text message survey for 7 days after each vaccination. This study included 50,950 vaccine recipients who responded the survey at least once. Informed consent about receiving text surveys was obtained from the vaccine recipients on the day of the first vaccination.
Results
The recipients of mRNA vaccines expressed 1.6 to 2.8 times more local and systemic reactions after dose 2 than after dose 1(p<0.0001), whereas ChAdOx1-S recipients reported significantly fewer local and systemic reactions after dose 2 than after dose 1(p<0.0001). Local and systemic reactions were approximately 1.3 and 2 times higher for heterologous vaccination than for BNT162b2/BNT162b2 and ChAdOx1-S/ChAdOx1-S, respectively. Young individuals, females, and heterologous vaccine regimens with ChAdOx1-S/BNT162b2 vaccines reported more adverse symptoms than older, males and homologous vaccine regimens.
Conclusions
Though heterologous schedules, young and female were associated with higher risk of solicited reactions after CVODI-19 vaccination, no critical issues have been rose. Actively considering heterologous schedules based on evidence of efficacy and safety seems desirable.; Summary

Korean summary

Key Message

Brief Communications

Clinical severity according to the primary infection variant in patients with suspected SARS-CoV-2 reinfection in Korea: Myung-Jae Hwang, Insob Hwang, Chungmin Park, Hanul Park, Taejong Son, Jong-Hun Kim; Epidemiol Health. 2023;45:e2023007. Published online December 21, 2022; DOI: https://doi.org/10.4178/epih.e2023007

823 View
136 Download

Abstract Summary PDF: Abstract
OBJECTIVES
We aimed to evaluate the severity of suspected severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reinfection according to variants of concern in Gyeongsangbuk-do and Daegu, Korea.
METHODS
The database of coronavirus disease 2019 (COVID-19) cases reported from epidemiological investigations through the integrated system operated by the Korea Disease Control and Prevention Agency, from January 20, 2020 to May 7, 2022 was combined with data from the Health Insurance Review and Assessment Service system. The severity odds ratio (SOR) in secondary infection episodes compared with primary infection was estimated using a generalized linear model with a binomial distribution.
RESULTS
In all patients, the SOR of SARS-CoV-2 reinfection was 0.89 (95% confidence interval [CI], 0.82 to 0.95), and the severity was lower than in the first infection. Patients who had been vaccinated within 91 days showed a more attenuated SOR (0.85; 95% CI, 0.74 to 0.98). However, despite vaccination, in patients with both primary and secondary infections caused by the Omicron variant, the severity was reduced to a lesser extent than in patients primarily infected with other variants.
CONCLUSIONS
We could make efforts to relieve the severity of COVID-19 in vulnerable populations, in which death is more likely, by recommending booster vaccinations in case of a resurgence.; Summary

Korean summary
국내 COVID-19 확진자들의 중증도 증가 위험은 재감염(2차감염) 시 감소하였지만, 1차감염과 재감염 모두 오미크론론 변이가 우세하였던 시기인 경우에는 오히려 증가하였다. 특히 마지막 예방접종일로부터 91일 이상인 확진자들과 60세이상 인구에서는 중증도 증가 위험이 더 높았다. 우리는 COVID-19가 장기화됨에 따라 취약인구집단에 대해 추가 예방접종을 권고함으로써 재감염시 중증도가 증가하는 것을 예방해야 할 필요가 있다.

Key Message
As COVID-19 prolongs, there is a need to recommend booster vaccinations for vulnerable populations to prevent the potential for increased severity in the event of reinfection.

Occupational inequalities in mortality in Korea: an analysis using nationally representative mortality follow-up data from the late 2000s and after: Eunjeong Noh, Young-Ho Khang; Epidemiol Health. 2022;44:e2022038. Published online April 6, 2022; DOI: https://doi.org/10.4178/epih.e2022038

4,175 View
326 Download
1 Citations

Abstract Summary PDF Supplementary Material

Abstract

Many Korean and international studies have found higher mortality rates and poorer health conditions among manual workers than among non-manual workers. However, a recent study using unlinked data argued that since the economic crisis in Korea in the late 2000s, the mortality estimates of male Korean non-manual workers have been higher than those of manual workers. Our work using individually linked data from the late 2000s and after aimed to examine mortality inequality by occupational class. We analyzed Korea National Health and Nutrition Examination Survey data that were individually linked to cause-of-death data. Cox regression analysis was used to identify the hazard ratios for mortality by occupational class. Of 11,766 males aged between 35 and 64, 397 died between 2007 and 2018: 142 died from cancer, 68 from cardiovascular disease, 88 from external causes, and 99 from other causes. After controlling for age, the mortality estimates for manual workers were 1.85 times higher than those for upper non-manual workers (p<0.05). We observed no evidence of reversed mortality inequality among occupational classes in Korea since the 2000s; this previously reported finding might have been due to numerator-denominator bias arising from the use of unlinked data.

Summary

Korean summary
개인 단위 연계자료가 아닌 분모(센서스)-분자(사망신고) 집합 자료를 사용하여 2000년대 후반 경제위기 이후 한국 남성 비육체직의 사망률이 육체직보다 높게 나타난다고 기존의 한 연구가 주장했다. 이 연구는 2000년대 이후 개인 단위로 연계된 코호트 자료를 활용하여 여전히 한국에서 육체직의 사망위험이 비육체직보다 높다는 점을 보임으로써, 기존 연구가 비연계자료의 사용으로 인한 분자-분모 바이어스(numerator-denominator bias) 때문에 그와 같은 결과를 보였다고 지적하였다.

Key Message
This paper using individually linked data from the late 2000s and after observed no evidence of reversed mortality inequality among occupational classes in Korea since the 2000s. The previously reported finding showing reversed occupational mortality inequality might have been due to numerator-denominator bias arising from the use of unlinked data.

Citations

Citations to this article as recorded by

Mortality of Suicide and Cerebro-Cardiovascular Diseases by Occupation in Korea, 1997–2020
Jungwon Jang, Inah Kim
International Journal of Environmental Research and Public Health.2022; 19(16): 10001. CrossRef

Dynamics of hospitalizations and in-hospital deaths from COVID-19 in northeast Brazil: a retrospective analysis based on the circulation of SARS-CoV-2 variants and vaccination coverage: Paulo Ricardo Martins-Filho, Adriano Antunes de Souza Araújo, Lucindo José Quintans-Júnior, Bárbara dos Santos Soares, Waneska de Souza Barboza, Taise Ferreira Cavalcante, Victor Santana Santos; Epidemiol Health. 2022;44:e2022036. Published online April 5, 2022; DOI: https://doi.org/10.4178/epih.e2022036

4,241 View
310 Download
5 Citations

Abstract PDF

Abstract

This study investigated the dynamics of hospitalizations and in-hospital deaths from coronavirus disease 2019 (COVID-19) throughout the pandemic in northeast Brazil, the Brazilian region with the worst socioeconomic indicators. In total, 141,445 cases, 8,213 hospital admissions, and 1,644 in-hospital deaths from COVID-19 were registered from March 14, 2020 to February 5, 2022. The overall rates of hospitalization and in-hospital deaths were 5.8% and 20.0%, respectively. The hospitalization and death rates significantly decreased over time, which may have been related to progress in vaccination. During the spread of the Gamma variant (January to June 2021), most hospitalized individuals were young adults, and approximately 40% of deaths occurred in this age group. During the predominance of Delta (July to December 2021), over 75% of deaths occurred among the elderly and unvaccinated or partially vaccinated individuals. This rate decreased to 42.3% during the transmission of the Omicron variant (January to February 2022), during which 34.6% of deaths were recorded among fully vaccinated individuals (2 doses) and 23.1% among those who received full vaccination and a booster. The Omicron-driven third wave was associated with a rise in the proportion of deaths among vaccinated individuals, especially among those who had not received a booster dose.

Summary

Korean summary

Key Message
The Omicron-driven third wave in Brazil was associated with a rise in the proportion of deaths among vaccinated individuals, especially among those who had not received a booster dose

Citations

Citations to this article as recorded by

Case-fatality rates and risk of death from COVID-19 and influenza A/H3N2 in Brazil: A nationwide ecological study
Paulo Ricardo Martins-Filho, Jerocílio Maciel de Oliveira Júnior, Cliomar Alves dos Santos
Enfermedades Infecciosas y Microbiología Clínica.2023; 41(3): 199. CrossRef
Comparison of Epidemiologic and Clinical COVID-19 Profiles in Children in Argentina, During Circulation of Original and Variant (Alpha, Gamma and Lambda) Strains
Angela Gentile, María Del Valle Juárez, Lucia Romero Bollon, Valeria Aprea, Erika Matteucci, Andrea Falaschi, Martin Brizuela, Cristina Euliarte, Gabriela Gregorio, Maria Paula Della Latta, Carlota Russ, Gabriela Nidia Ensinck, Liliana Saraceni, Miriam Br
Pediatric Infectious Disease Journal.2023; 42(2): 136. CrossRef
Case-fatality rates and risk of death from COVID-19 and influenza A/H3N2 in Brazil: A nationwide ecological study
Paulo Ricardo Martins-Filho, Jerocílio Maciel de Oliveira Júnior, Cliomar Alves dos Santos
Enfermedades infecciosas y microbiologia clinica (English ed.).2023; 41(3): 199. CrossRef
Impact of inactivated vaccines on decrease of viral RNA levels in individuals with the SARS-CoV-2 Omicron (BA.2) variant: A retrospective cohort study in Shanghai, China
Peng Yang, Bianli Dang, Wen Kang, Xiaofeng Li, Tianping Wang, Ruijuan Li, Meijuan Peng, Yushen Liu, Linxu Wang, Yan Cheng, Suhuai Yu, Min Wei, Han Gao, Wenzhen Kang, Lei Shang
Frontiers in Public Health.2023;[Epub] CrossRef
SARS-CoV-2 infection and mortality in pediatric patients with hematological malignancies and solid tumors
João Eduardo Andrade Tavares de Aguiar, Marcos Antônio Lima Carvalho, Simone Santana Viana, Paulo Ricardo Martins-Filho, Rosana Cipolotti
Pediatric Hematology and Oncology.2022; : 1. CrossRef

Trends in gastrointestinal infections before and during non-pharmaceutical interventions in Korea in comparison with the United States: Soyeoun Kim, Jinhyun Kim, Bo Youl Choi, Boyoung Park; Epidemiol Health. 2022;44:e2022011. Published online January 3, 2022; DOI: https://doi.org/10.4178/epih.e2022011

6,517 View
443 Download
1 Citations

Abstract Summary PDF

Abstract

OBJECTIVES
This study examined how trends in the weekly frequencies of gastrointestinal infectious diseases changed before and during the coronavirus disease 2019 (COVID-19) pandemic in Korea, and compared them with the trends in the United States.

METHODS

We compared the weekly frequencies of gastrointestinal infectious diseases (16 bacterial and 6 viral diseases) in Korea during weeks 5-52 before and after COVID-19. In addition, the weekly frequencies of 5 gastrointestinal infectious diseases in the United States (data from the Centers for Disease Control and Prevention) that overlapped with those in Korea were compared.

RESULTS

The mean weekly number of total cases of gastrointestinal infectious diseases in Korea showed a significant decrease (from 522 before COVID-19 to 245 after COVID-19, p<0.01). Only bacterial gastrointestinal infectious diseases caused by Campylobacter increased significantly; other bacterial gastrointestinal infectious diseases showed either a decrease or no change. The incidence of all other viral diseases decreased. In the United States, the weekly numbers of Salmonella, Campylobacter, typhoid, shigellosis, and hepatitis A virus cases sharply decreased after the COVID-19 outbreak. The weekly case numbers of all viral diseases markedly decreased in both countries; however, bacterial gastrointestinal infectious diseases showed a different pattern.

CONCLUSIONS

The incidence of gastrointestinal infectious diseases decreased after the COVID-19 outbreak. In contrast, Campylobacter infections showed an increasing trend in Korea, but a decreasing trend in the United States. Further studies are needed to elucidate the different trends in bacterial and viral infectious diseases before and after non-pharmaceutical interventions and between different countries.

Summary

Korean summary
한국과 미국 모두 코로나-19 발생 이후 위장관 감염 질환의 발생은 감소하고 있습니다. 하지만, 미국과 달리 한국에서는 캄필로박터 감염은 증가 하고 있습니다. 이는 COVID-19이 발생한 이후 캄필로박터 감염의 열악한 통제의 가능성을 설명할 수 있습니다.

Key Message
The incidence of gastrointestinal infectious diseases decreased after the COVID-19 outbreak, however, campylobacter infections showed an increasing trend in Korea, unlike the United States, which could explain the poor control of Campylobacter.

Citations

Citations to this article as recorded by

Impact of the COVID‐19 pandemic on the circulation of other pathogens in England
Lauren J. Hayes, Hannah Uri, Denisa Bojkova, Jindrich Cinatl, Mark N. Wass, Martin Michaelis
Journal of Medical Virology.2023;[Epub] CrossRef

A comparison of meta-analysis results with and without adjustment for the healthy worker effect: cancer mortality among workers in the semiconductor industry: Sung-Ho Hwang, Moon-Young Park, Won Jin Lee, Inho Park, Kimyong Hong, Donguk Park, Kyoung-Mu Lee; Epidemiol Health. 2021;43:e2021057. Published online September 8, 2021; DOI: https://doi.org/10.4178/epih.e2021057

5,100 View
162 Download
1 Citations

Abstract Summary PDF

Abstract

OBJECTIVES
This study compared the results of meta-analysis with and without adjustment for the healthy worker effect on the association between working in the semiconductor industry and cancer mortality.

METHODS

Six studies that reported standardized mortality ratios (SMRs) for cancers were selected for meta-analysis. Using a random-effects model, the SMR results from each study were combined for all cancers and leukemias to estimate the summary SMRs (95% confidence interval, CI). To adjust for the healthy worker effect, the relative standardized mortality ratio (rSMR=SMR_x/SMR_{not x}) were calculated using observed and expected counts for the specific cause of interest (i.e., all cancers and leukemias) and the observed and expected counts for all other causes of mortality. Then, the rSMR results were combined to estimate the summary rSMRs (95% CIs).

RESULTS

The SMRs for all causes of mortality among semiconductor industry workers ranged from 0.25 to 0.80, which reflects a significant healthy worker effect. A remarkable difference was found between the summary SMRs and the summary rSMRs. The summary SMR for all cancers was 0.70 (95% CI, 0.63 to 0.79) whereas the summary rSMR was 1.38 (95% CI, 1.20 to 1.59). The summary SMR for leukemia was 0.88 (95% CI, 0.72 to 1.07), and the summary rSMR was 1.88 (95% CI, 1.20 to 2.95).

CONCLUSIONS

Our results suggest that adjustment for the healthy worker effect (i.e., rSMR) may be useful in meta-analyses of cohort studies reporting SMRs.

Summary

Korean summary
본 연구에서는 반도체 근로자의 암사망률을 일반 인구와 비교하여 표준화사망비(SMR)를 제시한 연구를 대상으로 한 메타분석에서, summary SMR값(95% CI)과 건강근로자효과에 대해 보정한 rSMR을 산출한 후 종합한 summary rSMR값(95% CI)을 비교하였다. 모든 암의 경우 summary SMR=0.70 (0.63-0.79), summary rSMR=1.38(1.20-1.59)로 나타났으며, 백혈병의 경우 summary SMR=0.88 (0.72-1.07), summary rSMR=1.88(1.20-2.95)로 나타났다. 본 연구결과는 SMR 연구를 종합하는 메타분석 연구에서 rSMR과 같은 건강근로자효과에 대해 보정하는 방법론을 적용할 수 있음을 보여주는 사례이다.

Key Message
The relevance of epidemiological research reporting the standardized mortality ratios (SMRs) for workers in the semiconductor industry is often limited by the healthy worker effect. One of the simple correction methods in the relative standardized mortality ratio (rSMR). We observed significant rightward shift when the summary rSMRs were compared with the summary rSMRs, which suggest that adjustment for the healthy worker effect (i.e., rSMR) may be useful in meta-analyses of cohort studies reporting SMRs.

Citations

Citations to this article as recorded by

Health risks, emergency preparedness and Norwegian-Russian cooperation on Svalbard. A systematic review
Turid Austin Wæhler, Tor Ingebrigtsen
International Journal of Circumpolar Health.2022;[Epub] CrossRef

Hydrogen peroxide as an auxiliary treatment for COVID-19 in Brazil: a randomized double-blind clinical trial: Marielle Bazzo Di Domênico, Kauê Collares, Renan Brandenburg dos Santos, Ulysses Lenz, Vinícius Picoli Antunes, Vinicius Webber Godinho, Henrique Cesca, Thales Henrique Jincziwski Ponciano, Pedro Henrique Corazza; Epidemiol Health. 2021;43:e2021051. Published online August 3, 2021; DOI: https://doi.org/10.4178/epih.e2021051

8,613 View
252 Download
2 Citations

Abstract PDF

Abstract

OBJECTIVES
This study evaluated the effectiveness of hydrogen peroxide (H₂O₂) as mouthwash and nasal spray on symptom relief in coronavirus disease 2019 (COVID-19) patients.

METHODS

Patients positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), who were treated in a hospital or at home, and patients’ family members (not positive for SARS-CoV-2), were randomized into 2 groups: experimental (1% H₂O₂ for gargling, 0.5% H₂O₂ for nasal wash), and control. Patients gargled the solution 3 times a day, and applied the nasal spray twice a day, for a 7-day period. Family members received the same treatment as the treated COVID-19 patient. The researchers contacted patients every 2 days over an 8-day period. An average post-treatment interval of 8 days passed before testing family members.

RESULTS

The most frequent symptoms on day 0 were cough, loss of taste, and hyposmia; there were no significant differences between groups, independent of the period. The symptom of dyspnea presented a significant difference between days 2 and 4 (p<0.05). Among family members, 86.0% had no antibodies, 2.3% had antibodies, and 11.6% had active infections (4 in the experimental group and 6 in the control group). The most frequent adverse effects in the H₂O₂ group were a burning throat and nose.

CONCLUSIONS

H₂O₂ was not effective for the relief of COVID-19 symptoms and was associated with reports of transient adverse effects.

Summary

Korean summary

Key Message
The hydrogen peroxide (H2O2) at low concentrations disrupts the lipid membranes of some viruses through the action of oxygen free radicals. Nevertheless, the data obtained in the present study demonstrated that the use of the H2O2 as mouthwash and nasal spray was not effective on symptom relief in patients with COVID-19. Moreover, it was associated with transient adverse effects such as burning sensations in the nose and throat. Thus, the authors of this study advise against the use of H2O2 as a mouthwash and nasal spray to relieve COVID-19 symptoms and transmission.

Citations

Citations to this article as recorded by

Efficacy of Mouth Rinses and Nasal Spray in the Inactivation of SARS-CoV-2: A Systematic Review and Meta-Analysis of In Vitro and In Vivo Studies
Majdy Idrees, Bridget McGowan, Amr Fawzy, Abdulwahab Ali Abuderman, Ramesh Balasubramaniam, Omar Kujan
International Journal of Environmental Research and Public Health.2022; 19(19): 12148. CrossRef
Enhanced Nasal Deposition and Anti-Coronavirus Effect of Favipiravir-Loaded Mucoadhesive Chitosan–Alginate Nanoparticles
Khent Primo Alcantara, Nonthaneth Nalinratana, Nopporn Chutiwitoonchai, Agnes L. Castillo, Wijit Banlunara, Opa Vajragupta, Pornchai Rojsitthisak, Pranee Rojsitthisak
Pharmaceutics.2022; 14(12): 2680. CrossRef

Cancer incidence in the Tobruk area, eastern Libya: first results from Tobruk Medical Centre: Faisal Ismail, Ahmed G. Elsayed, Islam El-Garawani, Eman Abdelsameea; Epidemiol Health. 2021;43:e2021050. Published online August 3, 2021; DOI: https://doi.org/10.4178/epih.e2021050

5,763 View
270 Download
1 Citations

Abstract PDF

Abstract

OBJECTIVES
Cancer is a major cause of morbidity and mortality worldwide, and it is an increasing problem in developing countries. Estimation of the incidence of cancer is important, especially in regions with limited epidemiological data on cancer. Therefore, the aim of this study was to provide an updated report on the incidence of cancers in the Tobruk region in eastern Libya.

METHODS

Data on cancer patients from the records of the Department of Histopathology of Tobruk Medical Centre from January 2013 to June 2020 were included.

RESULTS

In total, 402 cases were recorded. Men patients accounted for 30.3% (n=122) of cases, and women patients represented 69.6% (n=280). The overall mean age at the time of the first diagnosis was 49.0±17.1 years. The most common malignancies were breast and uterine cancer in women (18.4%, n=74; 15.9%, n=64, respectively), colorectal cancer (11.6%, n=47; 26 in women and 21 in men), bladder cancer (8.2%, n=33; 8 in women and 25 in men), and thyroid cancer (8.0%, n=32; 23 in women and 9 in men).

CONCLUSIONS

Breast and uterine cancers were the most common cancers in women, and bladder and colorectal cancer were the most common cancers in men, followed by colorectal cancer in both genders. These data will help health authorities launch preventive plans for cancer in the region. Further studies to identify aetiological factors and cancer-related risk factors need to be conducted in the region.

Summary

Korean summary

Key Message
Cancer incidence in the Tobruk area, eastern Libya: first results from Tobruk Medical Centre; cancer is a major cause of morbidity and mortality worldwide and so in Libya; this is an updated report on the incidence of cancers in the Tobruk region in eastern Libya.

Citations

Citations to this article as recorded by

Libyan cancer patients at King Hussein Cancer Center for more than a decade, the current situation, and a future vision
Madiha Erashdi, Abdallah Al-Ani, Asem Mansour, Maysa Al-Hussaini
Frontiers in Oncology.2023;[Epub] CrossRef

Analysis of the difference in the perinatal mortality rate between white-collar and blue-collar workers in Japan, 1995-2015: Tasuku Okui; Epidemiol Health. 2020;42:e2020069. Published online November 24, 2020; DOI: https://doi.org/10.4178/epih.e2020069

5,928 View
114 Download

Abstract PDF: Abstract
OBJECTIVES
This study investigated differences in the perinatal mortality rate between white-collar and blue-collar workers.
METHODS
Data from the “Report of Vital Statistics: Occupational and Industrial Aspects” in Japan covering the period from 1995 to 2015 were used. Five-year maternal age groups from 15-19 years to 45-49 years were analyzed according to work type, and the perinatal mortality rate for each age group and the age-standardized perinatal mortality rate according to maternal age were calculated in each analyzed year. A Bayesian age-period-cohort analysis was used to estimate age, period, and cohort effects for the perinatal mortality rate according to work type. Moreover, the perinatal mortality rate ratios between types of workers were estimated for each age group, period, and cohort.
RESULTS
The estimated perinatal mortality rate ratios of blue-collar to white-collar workers were above 1 in most of the age groups and cohorts. The age effect for the perinatal mortality rate among white-collar workers was the largest in the 15-year to 19-year age group, whereas that among blue-collar workers was the largest in the 45-year to 49-year age group. Furthermore, the estimated perinatal rate ratio between white-collar and blue-collar workers tended to increase with maternal age. The magnitude of the decrease of the cohort effects on the perinatal mortality rate was rather larger in blue-collar workers in the cohorts born between 1946-1950 and 1996-2000.
CONCLUSIONS
The magnitude of the disparity markedly increased with maternal age. Thus, middle-aged blue-collar workers need more prenatal care and preventive measures for perinatal mortality than white-collar workers.; Summary

Korean summary

Key Message

Analyzing the effects of social distancing on the COVID-19 pandemic in Korea using mathematical modeling: Sunhwa Choi, Moran Ki; Epidemiol Health. 2020;42:e2020064. Published online September 7, 2020; DOI: https://doi.org/10.4178/epih.e2020064

9,392 View
493 Download
13 Citations

Abstract Summary PDF Supplementary Material

Abstract

OBJECTIVES
During the 6 months since the first coronavirus disease 2019 (COVID-19) patient was diagnosed in Korea on January 20, 2020, various prevention and control measures have been implemented according to the COVID-19 epidemic pattern. Therefore, this study aimed to estimate the reproductive numbers (R) for each epidemic stage to analyze the effects of the preventive measures and to predict the COVID-19 transmission trends.

METHODS

We estimated the transmission rates for each epidemic stage by fitting a COVID-19 transmission model, based on a deterministic mathematical model, to the data on confirmed cases. The effects of preventive measures such as social distancing by time period were analyzed, and the size and trends of future COVID-19 outbreaks were estimated.

RESULTS

The value of R was 3.53 from February18, 2020 to February 28, 2020, and the mean R reduced to 0.45 from March 14, 2020 to April 29, 2020, but it significantly increased to 2.69 from April 30, 2020 to May13, 2020 and it was maintained at 1.03 from May 14, 2020 to July 23, 2020.

CONCLUSIONS

According to the estimated R, it had fallen to below 1 and was maintained at that level owing to the isolation of infected persons by the public health authorities and social distancing measures followed by the general public. Then, the estimated R increased rapidly as the contact among individuals increased during the long holiday period from April 30, 2020 to May 5, 2020. Thereafter, the value of R dropped, with the continued use of preventive measures but remained higher than 1.00, indicating that the COVID-19 outbreak can be prolonged and develop into a severe outbreak at any time.

Summary

Korean summary
수학적 모델링을 통하여 코로나-19 유행양상에 따른 시기별 감염재생산수(reproductive number)를 추정하고, 시기별 방역정책의 효과를 분석하여 향후 유행의 규모와 유행 종료 시점 등을 예측하였다. 그 결과, 4월30일부터 5월5일까지의 긴 연휴 기간을 통해 사람들 간의 접촉이 증가하면서 감염재생산수가 급격히 증가하였고(4월 30일 - 5월 13일까지 평균 R=2.69), 그 후, 지속적인 방역조치로 인해 5월 14일-7월 23일까지 평균 R=1.03로 감소하였으나, 여전히 1보다 큰 값으로 나타나, 코로나-19유행이 지속되고 있으며 언제라도 다시 큰 유행으로 커질 수 있다고 예측되었다.

Key Message

Citations

Citations to this article as recorded by

Mathematical Modeling of COVID-19 Transmission and Intervention in South Korea: A Review of Literature
Hyojung Lee, Sol Kim, Minyoung Jeong, Eunseo Choi, Hyeonjeong Ahn, Jeehyun Lee
Yonsei Medical Journal.2023; 64(1): 1. CrossRef
The Effect of COVID–19 on Pediatric Intussusception: A Retrospective Study of a Single Center in South Korea with 10–Year Experience
Yeo Jin Yoo, Bo-Kyung Je, Ga Young Choi, Jee Hyun Lee, Sunkyu Choi, Ji Young Lee
Journal of the Korean Society of Radiology.2022; 83(2): 304. CrossRef
Trends of Internet Search Volumes for Major Depressive Disorder Symptoms During the COVID-19 Pandemic in Korea: An Interrupted Time-Series Analysis
Jieun Kim, Juhui Han, Byung Chul Chun
Journal of Korean Medical Science.2022;[Epub] CrossRef
A Novel Approach on Deep Learning—Based Decision Support System Applying Multiple Output LSTM-Autoencoder: Focusing on Identifying Variations by PHSMs’ Effect over COVID-19 Pandemic
Yong-Ju Jang, Min-Seung Kim, Chan-Ho Lee, Ji-Hye Choi, Jeong-Hee Lee, Sun-Hong Lee, Tae-Eung Sung
International Journal of Environmental Research and Public Health.2022; 19(11): 6763. CrossRef
Changes in the pattern and disease burden of acute viral respiratory infections before and during the COVID-19 pandemic
Chungmin Park, Donghan Lee, Inho Kim, Sujin Park, Gyehee Lee, Sangwoo Tak
Osong Public Health and Research Perspectives.2022; 13(3): 203. CrossRef
Modelling and analysis of fractional-order vaccination model for control of COVID-19 outbreak using real data
Hardik Joshi, Brajesh Kumar Jha, Mehmet Yavuz
Mathematical Biosciences and Engineering.2022; 20(1): 213. CrossRef
Exploring spatial distribution of social vulnerability and its relationship with the Coronavirus disease 2019: the Capital region of South Korea
Donghyun Kim
BMC Public Health.2022;[Epub] CrossRef
Impact of Nonpharmaceutical Interventions on the Incidence of Respiratory Infections During the Coronavirus Disease 2019 (COVID-19) Outbreak in Korea: A Nationwide Surveillance Study
Kyungmin Huh, Jaehun Jung, Jinwook Hong, MinYoung Kim, Jong Gyun Ahn, Jong-Hun Kim, Ji-Man Kang
Clinical Infectious Diseases.2021; 72(7): e184. CrossRef
Statistical Analysis of Patients Visiting Department of Acupuncture and Moxibustion in Korean Medicine Hospital Before and After COVID-19 - Focusing on a Korean Medicine Hospital in Daejeon -
Young Rok Lee, Hyun Ji Cha, Hyeon Kyu Choi, Min Ju Kim, Beom Seok Kim, Ki Jung Sung, Ju Hyun Jeon, Eun Seok Kim, Young Il Kim
Journal of Korean Medicine.2021; 42(2): 31. CrossRef
Dissection of non-pharmaceutical interventions implemented by Iran, South Korea, and Turkey in the fight against COVID-19 pandemic
Mohammad Keykhaei, Sogol Koolaji, Esmaeil Mohammadi, Reyhaneh Kalantar, Sahar Saeedi Moghaddam, Arya Aminorroaya, Shaghayegh Zokaei, Sina Azadnajafabad, Negar Rezaei, Erfan Ghasemi, Nazila Rezaei, Rosa Haghshenas, Yosef Farzi, Sina Rashedi, Bagher Larijan
Journal of Diabetes & Metabolic Disorders.2021; 20(2): 1919. CrossRef
Hybrid Model-Based Simulation Analysis on the Effects of Social Distancing Policy of the COVID-19 Epidemic
Bong Gu Kang, Hee-Mun Park, Mi Jang, Kyung-Min Seo
International Journal of Environmental Research and Public Health.2021; 18(21): 11264. CrossRef
Introducing the Networked Music Performance Library
Daniil Pilchen, Rebekah Wilson
Organised Sound.2021; 26(3): 340. CrossRef
Comparative Analysis of Patients Visiting Department of Korean Internal Medicine in a Korean Medicine Hospital Before and During COVID-19 - From July 2018 to June 2021 at Wonkwang University Jeonju Korean Medicine Hospital -
Ji-eun Lee, Yong-jeen Shin, Sun-ho Shin
The Journal of Internal Korean Medicine.2021; 42(6): 1255. CrossRef

Prospective cohort data quality assurance and quality control strategy and method: Korea HIV/AIDS Cohort Study: Soo Min Kim, Yunsu Choi, Bo Youl Choi, Minjeong Kim, Sang Il Kim, Jun Young Choi, Shin-Woo Kim, Joon Young Song, Youn Jeong Kim, Mee-Kyung Kee, Myeongsu Yoo, Jeong Gyu Lee, Bo Young Park; Epidemiol Health. 2020;42:e2020063. Published online September 4, 2020; DOI: https://doi.org/10.4178/epih.e2020063

7,647 View
184 Download
1 Citations

Abstract Summary PDF Supplementary Material

Abstract

OBJECTIVES
The aim of effective data quality control and management is to minimize the impact of errors on study results by identifying and correcting them. This study presents the results of a data quality control system for the Korea HIV/AIDS Cohort Study that took into account the characteristics of the data.

METHODS

The HIV/AIDS Cohort Study in Korea conducts repeated measurements every 6 months using an electronic survey administered to voluntarily consenting participants and collects data from 21 hospitals. In total, 5,795 sets of data from 1,442 participants were collected from the first investigation in 2006 to 2016. The data refining results of 2015 and 2019 were converted into the data refining rate and compared.

RESULTS

The quality control system involved 3 steps at different points in the process, and each step contributed to data quality management and results. By improving data quality control in the pre-phase and the data collection phase, the estimated error value in 2019 was 1,803, reflecting a 53.9% reduction from 2015. Due to improvements in the stage after data collection, the data refining rate was 92.7% in 2019, a 24.21%p increase from 2015.

CONCLUSIONS

Despite this quality management strategy, errors may still exist at each stage. Logically possible errors for the post-review refining of downloaded data should be actively identified with appropriate consideration of the purpose and epidemiological characteristics of the study data. To improve data quality and reliability, data management strategies should be systematically implemented.

Summary

Korean summary
이 연구는 한국 에이즈 코호트 자료의 연구 목적과 역학적 특성을 고려한 체계적인 질 관리 방법과 결과를 제시한다. 시간적 선후 관계를 고려한 로직을 활용한 자료정제 과정을 비롯한 3단계의 체계적인 질 관리 방법은 이제껏 없었던 국내 코호트 자료 질 관리에 도움이 될 것으로 사료된다.

Key Message

Citations

Citations to this article as recorded by

A Nationwide Evaluation of the Prevalence of Human Papillomavirus in Brazil (POP-Brazil Study): Protocol for Data Quality Assurance and Control
Jaqueline Driemeyer Correia Horvath, Marina Bessel, Natália Luiza Kops, Flávia Moreno Alves Souza, Gerson Mendes Pereira, Eliana Marcia Wendland
JMIR Research Protocols.2022; 11(1): e31365. CrossRef

Time-variant reproductive number of COVID-19 in Seoul, Korea: Seong-Geun Moon, Yeon-Kyung Kim, Woo-Sik Son, Jong-Hoon Kim, Jungsoon Choi, Baeg-Ju Na, Boyoung Park, Bo Youl Choi; Epidemiol Health. 2020;42:e2020047. Published online June 28, 2020; DOI: https://doi.org/10.4178/epih.e2020047

9,811 View
317 Download
2 Citations

Abstract Summary PDF Supplementary Material

Abstract

OBJECTIVES
To estimate time-variant reproductive number (R_t) of coronavirus disease 19 based on either number of daily confirmed cases or their onset date to monitor effectiveness of quarantine policies.

METHODS

Using number of daily confirmed cases from January 23, 2020 to March 22, 2020 and their symptom onset date from the official website of the Seoul Metropolitan Government and the district office, we calculated R_t using program R’s package “EpiEstim”. For asymptomatic cases, their symptom onset date was considered as -2, -1, 0, +1, and +2 days of confirmed date.

RESULTS

Based on the information of 313 confirmed cases, the epidemic curve was shaped like ‘propagated epidemic curve’. The daily R_t based on R_{t_c} peaked to 2.6 on February 20, 2020, then showed decreased trend and became <1.0 from March 3, 2020. Comparing both R_t from R_{t_c} and from the number of daily onset cases, we found that the pattern of changes was similar, although the variation of R_t was greater when using R_{t_c}. When we changed assumed onset date for asymptotic cases (-2 days to +2 days of the confirmed date), the results were comparable.

CONCLUSIONS

R_t can be estimated based on R_{t_c} which is available from daily report of the Korea Centers for Disease Control and Prevention. Estimation of R_t would be useful to continuously monitor the effectiveness of the quarantine policy at the city and province levels.

Summary

Korean summary
우리나라 전체와 각 시도별 일별 증상 발현자 수 또는 확진자 수를 이용하여 추정한 Rt로 방역정책의 효과를 국가 및 시도 수준에서 지속적으로 모니터링 할 필요가 있다.

Key Message

Citations

Citations to this article as recorded by

Reproduction Factor Based Latent Epidemic Model Inference: A Data-Driven Approach Using COVID-19 Datasets
Sujin Ahn, Minhae Kwon
IEEE Journal of Biomedical and Health Informatics.2023; 27(3): 1259. CrossRef
COVID-19 early-alert signals using human behavior alternative data
Anasse Bari, Aashish Khubchandani, Junzhang Wang, Matthias Heymann, Megan Coffee
Social Network Analysis and Mining.2021;[Epub] CrossRef

Follow-up investigation of asymptomatic COVID-19 cases at diagnosis in Busan, Korea: Miyoung Lee, Youngduck Eun, Kyounghee Park, Jeonghun Heo, Hyunjin Son; Epidemiol Health. 2020;42:e2020046. Published online June 23, 2020; DOI: https://doi.org/10.4178/epih.e2020046

11,558 View
304 Download
3 Citations

Abstract Summary PDF Supplementary Material

Abstract

OBJECTIVES
The objective of the study was to conduct a follow-up investigation of 10 asymptomatic patients at diagnosis among the 98 confirmed coronavirus disease 2019 (COVID-19) cases reported in Busan between February 21, 2020 and March 13, 2020 to determine whether asymptomatic infection and transmission during asymptomatic period are possible.

METHODS

The study analyzed 10 asymptomatic, confirmed COVID-19 cases to determine whether asymptomatic infection is possible. We conducted in-depth interviews with patients and guardians; interviews with primary physicians; review of medical records and drug utilization review (DUR) reports; and base station-based location tracking.

RESULTS

Among the 98, confirmed COVID-19 cases reported in Busan, the study analyzed 10 (10.2%) asymptomatic patients at diagnosis. The results confirmed that two (2.0%) patients reported to be asymptomatic during the initial epidemiological investigation, but turned symptomatic before diagnosis as per the in-depth interview results. Four cases (4.0%) of early detection led to confirmed diagnosis during the incubation period and presentation of symptoms after diagnosis. In addition, the remaining four patients (4.0%), having no subjective symptoms nor specific findings on chest radiography and computed tomography, remained asymptomatic until the isolation order was lifted. With regard to whether transmission during the asymptomatic period is possible, it was found that one out of 23 household contacts of the confirmed patients was identified as an additional confirmed case after coming in close contact with an index patient during the presymptomatic period.

CONCLUSIONS

Among the 98 confirmed cases, asymptomatic infection was confirmed in four cases (4.0%). In addition, there was one additional confirmed case in which the patient was a family member who came in close contact with an index patient during the incubation period, thereby confirming that transmission during the asymptomatic period is possible. The possibility of transmission during the asymptomatic period has been confirmed; therefore, it is necessary to review the measures for expanding contact tracing that is currently being applied starting one day prior to the onset of symptoms.

Summary

Korean summary
본 연구는 부산광역시에서 무증상으로 COVID-19에 진단된 10명의 환자를 추적조사하여 무증상 감염이 가능한가, 무증상기에 전파가 가능한가에 대해 확인하였다. 조사결과 4명(4.0%)의 무증상 감염환자를 확인하였고, 환자의 무증상기에 밀접 접촉한 가족 중 1명의 추가 환자를 확인하여 무증상기 전파가 가능하다는 것을 확인하였다.

Key Message

Citations

Citations to this article as recorded by

Characterization of COVID-19 cases in the early phase (March to July 2020) of the pandemic in Kenya
Philip Ngere, Joyce Onsongo, Daniel Langat, Elizabeth Nzioka, Faith Mudachi, Samuel Kadivane, Bernard Chege, Elvis Kirui, Ian Were, Stephen Mutiso, Amos Kibisu, Josephine Ihahi, Gladys Mutethya, Trufosa Mochache, Peter Lokamar, Waqo Boru, Lyndah Makayotto
Journal of Global Health.2022;[Epub] CrossRef
Asymptomatic Cases, the Hidden Challenge in Predicting COVID-19 Caseload Increases
Brett Snider, Bhumi Patel, Edward McBean
Infectious Disease Reports.2021; 13(2): 340. CrossRef
Efficacy and safety of traditional Chinese medicine combined with routine western medicine for the asymptomatic novel coronavirus disease (COVID–19)
Jiahao Wang, Xue Zhu, Yuying Sun, Xingcai Zhang, Wei Zhang
Medicine.2020; 99(35): e21927. CrossRef

First
Prev
Page of 3
Next
Last