ABSTRACT
Public health systems reported low mortality from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in East Asia, in low-income countries, and for children during the first year of the SARS-CoV-2 pandemic. These reports led commentators to suggest that cross-reactive immunity from prior exposure to other pathogens reduced fatality risk. Resolution of initial infection waves also contributed to speculation that herd immunity prevented further waves prior to vaccination. Serology instead implied that immunity was too limited to achieve herd immunity and that there was little impact from cross-reactive protection. Paediatric deaths exceeded those from influenza, with higher age-specific fatality risk in lower-income nations and similar fatality risk in East Asia compared with demographically similar regions. Neither pre-outbreak exposure to related pathogens nor immunity induced by initial infection waves are necessarily a reliable response to future pathogen outbreaks. Preparedness for future pathogen outbreaks should instead focus on strategies such as voluntary behavioural changes, nonpharmaceutical interventions, and vaccination.
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BACKGROUND: Atrial fibrillation is the most prevalent sustained cardiac arrhythmia. Electrical cardioversion, a well-established part of the rhythm control strategy, is probably underused in community settings. Here, we describe its use, safety, and effectiveness in a cohort of patients with atrial fibrillation treated in rural settings. METHODS: It is a retrospective cohort study. Data on all procedures from January 1, 2016, till December 1, 2022, in Tarusa Hospital, serving mostly a rural population of 15,000 people, were extracted from electronic health records. Data on the procedure's success, age, gender, body mass index, comorbidities, previous procedures, echocardiographic parameters, type and duration of arrhythmia, anticoagulation, antiarrhythmic drugs, transesophageal echocardiography, and settings were available. RESULTS: Altogether, 1,272 procedures in 435 patients were performed during the study period. The overall effectiveness of the procedure was 92%. Effectiveness was similar across all prespecified subgroups. Electrical cardioversion was less effective in patients undergoing the procedure for the first time (86%, 95% CI: 82-90) compared to repeated procedures (95%, 95% CI: 93-96), OR 0.39 (95% CI: 0.26-0.59). Complications were encountered in 13 (1.02%) procedures but were not serious. CONCLUSIONS: Electrical cardioversion is an immediately effective procedure that can be safely performed in community hospitals, both in inpatient and outpatient settings. Further studies with longer follow-up are needed to investigate the rate of sinus rhythm maintenance in these patients.
Subject(s)
Atrial Fibrillation , Humans , Electric Countershock , Retrospective Studies , Hospitals, Community , Treatment OutcomeABSTRACT
Background: The objective of this study was to develop a guideline on how to report result of a population-based cancer registry. Methods: The guideline's development involved a core working committee and a scientific committee comprising experts from diverse domains. The process comprised three steps: 1) a comprehensive review of existing tools and guidelines and the development of the initial draft of the guideline based on a review of literature, 2) refinement items through several rounds of focus group discussion among the core group, and development initial draft, and 3) Evaluation of the initial draft by scientific committee members. Items in the guideline were organized to accommodate reports of population-based cancer registries as a scientific manuscript. Results: The core committee developed 47 items distributed in the major heading of a scientific manuscript presented as a checklist. The evaluation of the scientific committee led to a consensus on the majority of the items included in the checklist. Among 10 committee members, 7 provided unreserved approval, validating each item's necessity, applicability, and comprehensibility in the checklist. Feedback from the remaining 3 members was carefully analyzed and integrated to enhance the guideline's robustness. Incorporating feedback, a first final draft was presented in a meeting of scientific and core working committee members. Collaborative discussion ensured clarity of expression for each items and a final checklist was developed. Conclusion: The guideline abbreviated as REPCAN offers a standardized framework for reporting population-based cancer registry, fostering transparency, comparability, and comprehensive data presentation. The guideline encourages flexibility while promoting comprehensive and robust reporting practices.
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Neoplasms , Routinely Collected Health Data , Humans , Research Report , Research Design , Checklist , Neoplasms/epidemiologyABSTRACT
BACKGROUND: A national framework for population-based cancer registration was established in Russia in the late 1990s. Data comparability and validity analyses found substantial differences across ten population-based cancer registries (PBCRs)in Northwest Russia, and only four out of ten met international standards. This study aimed to assess the completeness of the PBCR data of those registries. METHODS: Qualitative and quantitative methods recommended for completeness and timeliness assessment were applied to the data from ten Russian regional PBCRs in Northwest Russia, covering a population of 13 million. We used historic data methods (using several European PBCRs reference rates), mortality-to-incidence ratios (M:I) comparison, and death certificate methods to calculate the proportion of unregistered cases (Lincoln-Petersen estimator and Ajiki formula). RESULTS: Incidence rate trends of different cancer types were stable over time (except one region - Leningrad oblast). A slight drop in incidence rates in older age groups for several sites in the Northwestern regions was observed compared to the reference from European countries. Comparing M:I ratios against five-year survival revealed systematic differences in Leningrad oblast and Vologda oblast. Assessment of completeness revealed low or unrealistic estimates in Leningrad oblast and completeness below 90% in St. Petersburg. In other regions, the completeness was above 90%. The national annual report between 2008-2017 did not include about 10% of the cases collected later in the registry database of St. Petersburg. This difference was below 3% for Arkhangelsk oblast, Murmansk oblast, Novgorod oblast, Vologda oblast and the Republic of Karelia. CONCLUSIONS: Eight out of ten regional PBCRs in Northwest Russia collected data with an acceptable degree of completeness. Mostly populated St. Petersburg and Leningrad oblast did not reach such completeness. PBCR data from several regions in Northwest Russia are suitable for epidemiological research and monitoring cancer control activities.
Subject(s)
Neoplasms , Routinely Collected Health Data , Humans , Aged , Neoplasms/epidemiology , Registries , Incidence , Russia/epidemiologyABSTRACT
BACKGROUND: About half of cancer deaths in Brazil occur among individuals of working-age (under 65 years for men, under 60 for women), resulting in a substantial economic impact for the country. We aimed to estimate the years of potential productive life lost (YPPLL) and value the productivity lost due to premature deaths from cancer between 2001 and 2015 and the projected to 2030. METHODS: We used the Human Capital Approach to estimate the productivity losses corresponding to YPPLL for cancer deaths in working age people (15-64 years). Mortality data were obtained from the Mortality Information System from 2001 to 2015 and projected between 2016 and 2030. Economic data were obtained from the Continuous National Household Sample Survey and forecasted to 2030. Productivity lost was calculated as the monetary value arising from YPPLL in Int$(2016). RESULTS: Between 2001 and 2030, a total of 2.3 million premature deaths from all cancers combined were observed and forecasted in Brazil (57% men, 43% women), corresponding to 32 million YPPLL and Int$141.3 billion in productivity losses (men: Int$102.5 billion, women: Int$38.8 billion). Between 2001 and 2030, among men, lung (Int$ 12.6 billion), stomach (Int$ 10.6 billion) and colorectal (Int$ 9.4 billion) cancers were expected to contribute to the greatest productivity losses; and among women, it will be for breast (Int$ 10.0 billion), cervical (Int$ 6.4 billion) and colorectal (Int$ 3.2 billion) cancers. CONCLUSIONS: Many preventable cancers result in high lost productivity, suggesting measure to reduce smoking prevalence, alcohol consumption, physical inactivity and inadequate diet, improving screening programs and increasing vaccination coverage for human papillomavirus and hepatitis B would have a positive impact on the economy, as well as reducing morbidity and mortality from cancer.
Subject(s)
Cost of Illness , Mortality, Premature , Neoplasms , Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Brazil/epidemiology , Efficiency , Neoplasms/mortalityABSTRACT
BACKGROUND: Eastern Europe and Central Asia (EECA) countries have higher cervical and breast cancer mortality rates and later stage at diagnosis compared with the rest of WHO European Region. The aim was to explore current early detection practices including "dispensarization" for breast and cervix cancer in the region. METHODS: A questionnaire survey on early detection practices for breast and cervix cancer was sent to collaborators in 11 countries, differentiating services in the primary health setting, and population-based programs. Responses were received from Armenia, Belarus, Georgia, Kazakhstan, Kyrgyzstan, the Russian Federation (Arkhangelsk, Samara and Tomsk regions), Tajikistan, Ukraine, and Uzbekistan. RESULTS: All countries but Georgia, Kyrgyzstan, and the Russian Federation had opportunistic screening by clinical breast exam within "dispensarization" program. Mammography screening programs, commonly starting from age 40, were introduced or piloted in eight of nine countries, organized at national oncology or screening centres in Armenia, Belarus and Georgia, and within primary care in others. Six countries had "dispensarization" program for cervix cancer, mostly starting from the age 18, with smears stained either by Romanowsky-Giemsa alone (Belarus, Tajikistan and Ukraine), or alternating with Papanicolaou (Kazakhstan and the Russian Federation). In parallel, screening programs using Papanicolaou or HPV test were introduced in seven countries and organized within primary care. CONCLUSION: Our study documents that parallel screening systems for both breast and cervix cancers, as well as departures from evidence-based practices are widespread across the EECA. Within the framework of the WHO Initiatives, existing opportunistic screening should be replaced by population-based programs that include quality assurance and control.
Subject(s)
Uterine Cervical Neoplasms , Female , Humans , Adult , Adolescent , Uterine Cervical Neoplasms/diagnosis , Early Detection of Cancer , Europe, Eastern/epidemiology , Asia, Central/epidemiology , RussiaABSTRACT
Background: We provide a comprehensive view of the impact of alcohol consumption, tobacco smoking, excess body weight, and human papillomavirus (HPV) infection on cancer mortality and years of life lost (YLLs) in Brazil, Russia, India, China, South Africa, the United Kingdom (UK), and United States (US). Methods: We collected population attributable fractions of the four risk factors from global population-based studies and applied these to estimates of cancer deaths in 2020 to obtain potentially preventable cancer deaths and their 95% confidence intervals (CIs). Using life tables, we calculated the number and age-standardised rates of YLLs (ASYR). Findings: In Brazil, Russia, India, China, South Africa, the UK, and the US in 2020, an estimated 5.9 million (3.3 million-8.6 million) YLLs from cancer were attributable to alcohol consumption, 20.8 million (17.0 million-24.6 million) YLLs to tobacco smoking, 3.1 million (2.4 million-3.8 million) YLLs to excess body weight, and 4.0 million (3.9 million-4.2 million) YLLs to HPV infection. The ASYR from cancer due to alcohol consumption was highest in China (351.4 YLLs per 100,000 population [95% CI 194.5-519.2]) and lowest in the US (113.5 [69.6-157.1]) and India (115.4 [49.7-172.7). For tobacco smoking, China (1159.9 [950.6-1361.8]) had the highest ASYR followed by Russia (996.8 [831.0-1154.5). For excess body weight, Russia and the US had the highest ASYRs (385.1 [280.6-481.2] and 369.4 [299.6-433.6], respectively). The highest ASYR due to HPV infection was in South Africa (457.1 [453.3-462.6]). ASYRs for alcohol consumption and tobacco smoking were higher among men than women, whereas women had higher ASYRs for excess body weight and HPV infection. Interpretation: Our findings demonstrate the importance of cancer control efforts to reduce the burden of cancer death and YLLs due to modifiable cancer risk factors and promote the use of YLLs to summarise disease burden. Funding: Cancer Research UK.
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BACKGROUND: Monitoring vaccine effectiveness (VE) remains a priority for epidemiological research throughout the COVID-19 pandemic. VE against infection declines with the emergence of new SARS-CoV-2 variants of concern (VOC), but VE against the severe disease remains high. Therefore, we aimed to estimate the effectiveness of COVID-19 vaccines used in Russia against lung injury during Delta and Omicron VOC surges. METHODS: We designed a case-control study (test-negative design) to estimate VE against any (any volume of involved lung parenchyma) and severe (>50% of involved parenchyma) lung injury detected on computer tomography and associated with COVID-19 between October 1, 2021-April 28, 2022 (Delta VOC dominance period followed by Omicron dominance period). We included the data of patients with symptomatic confirmed SARS-CoV-2 infection referred to the low-dose computer tomography triage centres. RESULTS: Among 23996 patients in the primary analysis, 13372 (55.7%) had any lung injury, and 338 (1.4%) had severe lung injury. The adjusted for age, sex and triage centre VE estimates against any lung injury were 56% (95% confidence interval 54-59) for two-dose Gam-COVID-Vac (Sputnik V), 71% (68-74) for three-dose Gam-COVID-Vac (booster), 2% (-27 to 24) for EpiVacCorona, and 46% (37-53) for CoviVac. VE estimates against severe lung injury were 76% (67-82) for two-dose Gam-COVID-Vac (Sputnik V), 87% (76-93) for three-dose Gam-COVID-Vac, 36% (-63 to 75) for EpiVacCorona, and 80% (45-92) for CoviVac. CONCLUSIONS: Gam-COVID-Vac remained effective against lung injury associated with COVID-19 during Delta and Omicron VOC surges, and one Gam-COVID-Vac booster could be seen as an appropriate option after a two-dose regimen. CoviVac was also effective against lung injury. EpiVacCorona use in population-based vaccination should be halted until effectiveness and efficacy evidence is provided. Trial registration The joint study of COVID-19 vaccine effectiveness in St. Petersburg was registered at ClinicalTrials.gov (NCT04981405, date of registration-August 4, 2021).
Subject(s)
COVID-19 , Lung Injury , COVID-19/epidemiology , COVID-19 Vaccines , Case-Control Studies , Humans , Pandemics , SARS-CoV-2 , Vaccines, SyntheticABSTRACT
BACKGROUND: Studies of mRNA and vector-based vaccines used in different countries report acceptable levels of effectiveness against SARS-CoV-2 infection caused by the Delta variants of SARS-CoV-2. No studies estimated vaccine effectiveness (VE) of Gam-COVID-Vac and other vaccines used in Russia against symptomatic infection with Delta variant. In this population-based case-control study, we aimed to estimate the effectiveness of the Russian COVID-19 vaccines against symptomatic SARS-CoV-2 during the recent outbreak caused by the Delta VOC in October 2021 in St. Petersburg, Russia. METHODS: Cases were symptomatic patients with confirmed SARS-CoV-2 (using polymerase chain reaction (PCR) test) referred to low-dose computed tomography (LDCT) triage in two outpatient centres between October 6 and 14, 2021 during the Delta variant outbreak. We recruited the controls during the representative survey of the seroprevalence study conducted during the same period in St. Petersburg using random digit dialling. In the primary analysis, we used logistic regression models to estimate the adjusted (age, sex, and history of confirmed COVID-19) VE against symptomatic SARS-CoV-2 resulted in a referral to triage centre for three vaccines used in Russia: Gam-COVID-Vac, EpiVacCorona, and CoviVac. RESULTS: We included 1,254 cases and 2,747 controls recruited between the 6th and 14th of October in the final analysis. VE was 56% (95% CI: 48 to 63) for Gam-COVID-Vac (Sputnik V), 49% (95% CI: 29 to 63) for 1-dose Gam-COVID-Vac (Sputnik V) or Sputnik Light, -58% (95% CI: -225 to 23) for EpiVacCorona and 40% (95% CI: 3 to 63) for CoviVac. Without adjustment for the history of confirmed COVID-19 VE for all vaccines was lower, except for one-dose Gam-COVID-Vac (Sputnik Light). The adjusted VE was slightly lower in women - 51% (95% CI: 39 to 60) than men - 65% (95% CI: 5 to 73). CONCLUSIONS: Our preliminary results show that in contrast to other Russian vaccines, Gam-COVID-Vac is effective against symptomatic SARS-CoV-2 infection caused by Delta VOC. Effectiveness is likely higher than the estimated 56% due to bias arising from high prevalence of the past COVID-19 in St. Petersburg.
Subject(s)
COVID-19 Vaccines , COVID-19 , COVID-19/epidemiology , COVID-19/prevention & control , Case-Control Studies , Female , Humans , Male , RNA, Messenger , SARS-CoV-2/genetics , Seroepidemiologic Studies , Vaccines, SyntheticABSTRACT
BACKGROUND: The results of a randomised trial showed the safety and efficacy of Gam-COVID-Vac against COVID-19. However, compared to other vaccines used across the globe, the real-world data on the effectiveness of Gam-COVID-Vac, especially against the disease caused by the Delta variant of concern, was limited. We aimed to assess the effectiveness of vaccination mainly conducted with Gam-COVID-Vac in St. Petersburg, Russia. METHODS: We designed a case-control study to assess the vaccine effectiveness (VE) against referral to hospital. Self-reported vaccination status was collected for individuals with confirmed SARS-CoV-2 infection who were referred for initial low-dose computed tomography (LDCT) triage in two outpatient centres in July 3-August 9, 2021, in St. Petersburg, Russia. We used logistic regression models to estimate the adjusted (for age, sex, and triage centre) VE for complete (14 days or more after the second dose) vaccination. We estimated the VE against referral for hospital admission, COVID-19-related lung injury assessed with LDCT, and decline in oxygen saturation. RESULTS: In the final analysis, 13,893 patients were included, 1291 (9.3%) patients met our criteria for complete vaccination status, and 495 (3.6%) were referred to hospital. In the primary analysis, the adjusted VE against referral to hospital was 81% (95% confidence interval: 68-88) for complete vaccination. The VE against referral to hospital was more pronounced in women (84%, 95% CI: 66-92) compared to men (76%, 95% CI: 51-88). Vaccine protective effect increased with increasing lung injury categories, from 54% (95% CI: 48-60) against any sign of lung injury to 76% (95% CI: 59-86) against more than 50% lung involvement. A sharp increase was observed in the probability of hospital admission with age for non-vaccinated patients in relation to an almost flat relationship for the completely vaccinated group. CONCLUSIONS: COVID-19 vaccination was effective against referral to hospital in patients with symptomatic SARS-CoV-2 infection in St. Petersburg, Russia. This protection is probably mediated through VE against lung injury associated with COVID-19.
Subject(s)
COVID-19 , Lung Injury , COVID-19/prevention & control , COVID-19 Vaccines , Case-Control Studies , Female , Hospitals , Humans , Male , Referral and Consultation , SARS-CoV-2 , Vaccine EfficacyABSTRACT
BACKGROUND: The COVID-19 pandemic in Russia has already resulted in 500,000 excess deaths, with more than 5.6 million cases registered officially by July 2021. Surveillance based on case reporting has become the core pandemic monitoring method in the country and globally. However, population-based seroprevalence studies may provide an unbiased estimate of the actual disease spread and, in combination with multiple surveillance tools, help to define the pandemic course. This study summarises results from four consecutive serological surveys conducted between May 2020 and April 2021 at St. Petersburg, Russia and combines them with other SARS-CoV-2 surveillance data. METHODS: We conducted four serological surveys of two random samples (May-June, July-August, October-December 2020, and February-April 2021) from adults residing in St. Petersburg recruited with the random digit dialing (RDD), accompanied by a telephone interview to collect information on both individuals who accepted and declined the invitation for testing and account for non-response. We have used enzyme-linked immunosorbent assay CoronaPass total antibodies test (Genetico, Moscow, Russia) to report seroprevalence. We corrected the estimates for non-response using the bivariate probit model and also accounted the test performance characteristics, obtained from independent assay evaluation. In addition, we have summarised the official registered cases statistics, the number of hospitalised patients, the number of COVID-19 deaths, excess deaths, tests performed, data from the ongoing SARS-CoV-2 variants of concern (VOC) surveillance, the vaccination uptake, and St. Petersburg search and mobility trends. The infection fatality ratios (IFR) have been calculated using the Bayesian evidence synthesis model. FINDINGS: After calling 113,017 random mobile phones we have reached 14,118 individuals who responded to computer-assisted telephone interviewing (CATI) and 2,413 provided blood samples at least once through the seroprevalence study. The adjusted seroprevalence in May-June, 2020 was 9.7% (95%: 7.7-11.7), 13.3% (95% 9.9-16.6) in July-August, 2020, 22.9% (95%: 20.3-25.5) in October-December, 2021 and 43.9% (95%: 39.7-48.0) in February-April, 2021. History of any symptoms, history of COVID-19 tests, and non-smoking status were significant predictors for higher seroprevalence. Most individuals remained seropositive with a maximum 10 months follow-up. 92.7% (95% CI 87.9-95.7) of participants who have reported at least one vaccine dose were seropositive. Hospitalisation and COVID-19 death statistics and search terms trends reflected the pandemic course better than the official case count, especially during the spring 2020. SARS-CoV-2 circulation showed rather low genetic SARS-CoV-2 lineages diversity that increased in the spring 2021. Local VOC (AT.1) was spreading till April 2021, but B.1.617.2 substituted all other lineages by June 2021. The IFR based on the excess deaths was equal to 1.04 (95% CI 0.80-1.31) for the adult population and 0.86% (95% CI 0.66-1.08) for the entire population. CONCLUSION: Approximately one year after the COVID-19 pandemic about 45% of St. Petersburg, Russia residents contracted the SARS-CoV-2 infection. Combined with vaccination uptake of about 10% it was enough to slow the pandemic at the present level of all mitigation measures until the Delta VOC started to spread. Combination of several surveillance tools provides a comprehensive pandemic picture.
Subject(s)
COVID-19 , SARS-CoV-2 , Adult , Antibodies, Viral , Bayes Theorem , COVID-19/epidemiology , Humans , Pandemics , Seroepidemiologic StudiesABSTRACT
BACKGROUND: Nowadays, various simulation approaches for evaluation and decision making in cancer screening can be found in the literature. This paper presents an overview of approaches used to assess screening programs for breast, lung, colorectal, prostate, and cervical cancers. Our main objectives are to describe methodological approaches and trends for different cancer sites and study populations, and to evaluate quality of cancer screening simulation studies. METHODS: A systematic literature search was performed in Medline, Web of Science, and Scopus databases. The search time frame was limited to 1999-2018 and 7101 studies were found. Of them, 621 studies met inclusion criteria, and 587 full-texts were retrieved, with 300 of the studies chosen for analysis. Finally, 263 full texts were used in the analysis (37 were excluded during the analysis). A descriptive and trend analysis of models was performed using a checklist created for the study. RESULTS: Currently, the most common methodological approaches in modeling cancer screening were individual-level Markov models (34% of the publications) and cohort-level Markov models (41%). The most commonly evaluated cancer types were breast (25%) and colorectal (24%) cancer. Studies on cervical cancer evaluated screening and vaccination (18%) or screening only (13%). Most studies have been conducted for North American (42%) and European (39%) populations. The number of studies with high quality scores increased over time. CONCLUSIONS: Our findings suggest that future directions for cancer screening modelling include individual-level Markov models complemented by screening trial data, and further effort in model validation and data openness.
Subject(s)
Early Detection of Cancer , Neoplasms , Cohort Studies , Humans , Male , Mass Screening , Neoplasms/diagnosisABSTRACT
BACKGROUND: Despite the elaborate history of statistical reporting in the USSR, Russia established modern population-based cancer registries (PBCR) only in the 1990s. The quality of PBCRs data has not been thoroughly analyzed. This study aims at assessing the comparability and validity of cancer statistics in regions of the Northwestern Federal District (NWFD) of Russia. MATERIAL AND METHODS: Data from ten Russian regional PBCRs covering â¼13 million (â¼5 million in St. Petersburg) were processed in line with IARC/IACR and ENCR recommendations. We extracted and analyzed all registered cases but focused on cases diagnosed between 2008 and 2017. For comparability and validity assessment, we applied established qualitative and quantitative methods. RESULTS: Data collection in NWFD is in line with international standards. Distributions of diagnosis dates revealed higher variation in several regions, but overall, distributions are relatively uniform. The proportion of multiple primaries between 2008 and 2017 ranged from 6.7% in Vologda Oblast to 12.4% in Saint-Petersburg. We observed substantial regional heterogeneity for most indicators of validity. In 2013-2017, proportions of morphologically verified cases ranged between 61.7 and 89%. Death certificates only (DCO) cases proportion was in the range of 1-14% for all regions, except for Saint-Petersburg (up to 23%). The proportion of cases with a primary site unknown was between 1 and 3%. Certain cancer types (e.g., pancreas, liver, hematological malignancies, and CNS tumors) and cancers in older age groups showed lower validity. CONCLUSION: While the overall level of comparability and validity of PBCRs data of four out of ten regions of NWFD of Russia meets the international standards, differences between the regions are substantial. The local instructions for cancer registration need to be updated and implemented. The data validity assessment also reflects pitfalls in the quality of diagnosis of certain cancer types and patient groups.
Subject(s)
Hematologic Neoplasms , Neoplasms , Aged , Humans , Incidence , Neoplasms/epidemiology , Registries , Russia/epidemiologyABSTRACT
Properly conducted serological survey can help determine infection disease true spread. This study aims to estimate the seroprevalence of SARS-CoV-2 antibodies in Saint Petersburg, Russia accounting for non-response bias. A sample of adults was recruited with random digit dialling, interviewed and invited for anti-SARS-CoV-2 antibodies. The seroprevalence was corrected with the aid of the bivariate probit model that jointly estimated individual propensity to agree to participate in the survey and seropositivity. 66,250 individuals were contacted, 6,440 adults agreed to be interviewed and blood samples were obtained from 1,038 participants between May 27 and June 26, 2020. Naïve seroprevalence corrected for test characteristics was 9.0% (7.2-10.8) by CMIA and 10.5% (8.6-12.4) by ELISA. Correction for non-response decreased estimates to 7.4% (5.7-9.2) and 9.1% (7.2-10.9) for CMIA and ELISA, respectively. The most pronounced decrease in bias-corrected seroprevalence was attributed to the history of any illnesses in the past 3 months and COVID-19 testing. Seroconversion was negatively associated with smoking status, self-reported history of allergies and changes in hand-washing habits. These results suggest that even low estimates of seroprevalence can be an overestimation. Serosurvey design should attempt to identify characteristics that are associated both with participation and seropositivity.
Subject(s)
Antibodies, Viral/blood , COVID-19 Serological Testing/methods , COVID-19/blood , COVID-19/epidemiology , Pandemics , SARS-CoV-2/immunology , Adolescent , Adult , Aged , COVID-19/diagnosis , COVID-19/virology , Cross-Sectional Studies , Enzyme-Linked Immunosorbent Assay , Female , Humans , Immunoglobulin G/blood , Longitudinal Studies , Luminescent Measurements , Male , Middle Aged , Russia/epidemiology , Self Report , Seroconversion , Seroepidemiologic Studies , Smoking , Young AdultABSTRACT
BACKGROUND: Russia, then part of the Union of Soviet Socialist Republics (the USSR), introduced compulsory cancer registration in 1953, but a clear overall contemporary description of the cancer surveillance system in Russia is not available. METHODS: We summarized historical landmarks and the development of the standards of classification and coding of neoplasms in Russia and described current population-based cancer registries' (PBCR) procedures and practices. RESULTS: Cancer registration is organized according to the administrative division of the Russian Federation. More than 600,000 cases are registered annually. All medical facilities, without exception, are required to notify the PBCR about newly diagnosed cases, and each regional PBCR is responsible for registering all cancers diagnosed in citizens residing in the region. The data collection can be described as passive and exhaustive. Hematological malignancies, brain, and CNS tumors are often not referred to cancer hospitals in some regions, explaining the problems in registering these cancers. CONCLUSION: Russia's cancer registration system is population-based, and practices seem to be generally internationally comparable. However, coding practices and national guidelines are still outdated and not up to the most recent international recommendations. Further analyses are needed to assess the comparability, validity, completeness, and timeliness of Russia's PBCRs data.
Subject(s)
Neoplasms , Registries , Humans , Neoplasms/epidemiology , Russia/epidemiologyABSTRACT
Geographical variation in severe acute respiratory syndrome coronavirus 2 (SARS--CoV--2) spread requires seroprevalence studies based on local tests, but robust validation is needed. We summarize an evaluation of antibody tests used in a serological study of SARS--CoV--2 in Saint Petersburg, Russia. We validated three different antibody assays: chemiluminescent microparticle immunoassay (CMIA) Abbott Architect SARS--CoV--2 immunoglobulin G (IgG), enzyme- linked immunosorbent assay (ELISA) CoronaPass total antibodies test, and ELISA SARS--CoV--2--IgG--EIA--BEST. Clinical sensitivity was estimated with the SARS--CoV--2 polymerase chain reaction (PCR) test as the gold standard using manufacturer recommended cutoff. Specificity was estimated using pre-pandemic sera samples. The median time between positive PCR test results and antibody tests was 21 weeks. Measures of concordance were calculated against the microneutralization test (MNA).Sensitivity was equal to 91.1% (95% confidence intervbal [CI]: 78.8-97.5), 90% (95% CI: 76.4-96.4), and 63.1% (95% CI [50.2-74.7]) for ELISA Coronapass, ELISA Vector-Best, and CMIA Abbott, respectively. Specificity was equal to 100% for all the tests. Comparison of receiver operating characteristics has shown lower AUC for CMIA Abbott. The cut-off SC/O ratio of 0.28 for CMIA Abbott resulted in a sensitivity of 80% at the same level of specificity. Less than 33% of the participants with positive antibody test results had neutralizing antibodies in titers 1:80 and above. Antibody assays results and MNA correlated moderately. This study encourages the use of local antibody tests and sets the reference for seroprevalence correction. Available tests' sensitivity allows detecting antibodies within the majority of PCR- positive individuals. The Abbott assay sensitivity can be improved by incorporating a new cut-off. Manufacturers' test characteristics may introduce bias into the study results.
Subject(s)
Antibodies, Viral/blood , COVID-19 Serological Testing , COVID-19/diagnosis , SARS-CoV-2/isolation & purification , Antibodies, Neutralizing/blood , COVID-19/blood , COVID-19/epidemiology , Enzyme-Linked Immunosorbent Assay , Humans , Immunoassay , Russia/epidemiology , SARS-CoV-2/immunology , Sensitivity and Specificity , Seroepidemiologic StudiesABSTRACT
BACKGROUND: Screening for breast cancer and cervical cancer in the newly independent states of the former Soviet Union is largely opportunistic, and countries in the region have among the highest cervical cancer incidence in the WHO European Region. We aimed to compare the stage-specific distributions and changes over time in breast cancer and cervical cancer incidence in the newly independent states of the former Soviet Union. METHODS: We collected breast cancer and cervical cancer incidence data from official statistics from Armenia, Azerbaijan, Belarus, Georgia, Kazakhstan, Kyrgyzstan, Republic of Moldova, Russian Federation, Ukraine, and Uzbekistan for the years 2008-17 by tumour, node, metastasis (TNM) stage, and by age where population-based cancer registry data were available. We used log-linear regression to quantify the changes over time in age-standardised rates. FINDINGS: During the period 2013-17, more than 50% of breast cancer cases across the analysed countries, and more than 75% of breast cancer cases in Belarus, Kazakhstan, and Ukraine, were registered at stages I-II. The proportion of stage I breast cancer cases was highest in the screening age group (50-69 years) compared with other ages in Moldova and the Russian registries, but was highest in those aged 15-49 years in Georgia and Ukraine. Breast cancer stage-specific incidence rates increased over time, most prominently for stage I cancers. For cervical cancer, the proportions of cancers diagnosed at a late stage (stages III and IV) were high, particularly in Moldova and Armenia (>50%). The proportion of stage I cervical cancer cases decreased with age in all countries, whereas the proportions of late stage cancers increased with age. Stage-specific incidence rates of cervical cancer generally increased over the period 2008-17. INTERPRETATION: Our results suggest modest progress in early detection of breast cancer in the newly independent states of the former Soviet Union. The high proportions of early-stage disease in the absence of mammography screening (eg, in Belarus) provide a benchmark for what is achievable with rapid diagnosis. For cervical cancer, there is a need to tackle the high burden and unfavourable stage-specific changes over time in the region. A radical shift in national policies away from opportunistic screening toward organised, population-based, quality-assured human papillomavirus vaccination and screening programmes is urgently needed. FUNDING: Union for International Cancer Control, WHO Regional Office for Europe, and Ministry of Health of Ukraine.
Subject(s)
Breast Neoplasms/pathology , Uterine Cervical Neoplasms/pathology , Adolescent , Adult , Aged , Breast Neoplasms/classification , Breast Neoplasms/epidemiology , Early Detection of Cancer , Female , Follow-Up Studies , Humans , Incidence , Middle Aged , Neoplasm Staging , USSR/epidemiology , Uterine Cervical Neoplasms/classification , Uterine Cervical Neoplasms/epidemiology , Young AdultABSTRACT
BACKGROUND: Stomach cancer incidence and mortality rates are declining across circumpolar nations, but the burden may not be distributed equally across subpopulations, including Indigenous peoples. Our objective was to examine stomach cancer incidence and mortality trends across circumpolar populations. METHODS: Cancer incidence and mortality data from 1999-2016 were obtained from the Canadian Cancer Registry, Canadian Vital Statistics, CDC WONDER, NORDCAN, Northwestern Russian cancer registries, and National Cancer Reports. The direct method was used to calculate 10-year rolling age-standardized incidence and mortality rates to the world (WHO 2000-2025) and 2011 Canadian standard populations. Standardized incidence rate ratios (SRR) were calculated. Data were stratified by sex, year, and region. U.S. data were broken down by race [White; American Indian/Alaska Native (AIAN)]. Race data were not available from non-U.S. cancer registries. RESULTS: Most populations showed declining incidence and mortality rates over time. Incidence rates among Greenland males and females, Alaska AIAN males and females, and Northern Canadian both sexes were elevated compared with regional counterparts and remained stable. The largest male SRR was observed among Alaska AIAN versus Alaska Whites [SRR = 3.82; 95% confidence interval (95% CI), 2.71-5.37]. The largest female SRR was observed among Alaska AIAN versus Alaska Whites (SRR = 4.10; 95% CI, 2.62-6.43). CONCLUSIONS: Despite stomach cancer incidence and mortality rates declining overall, some northern and Indigenous populations experience elevated and stable incidence and mortality rates. IMPACT: There is a need to address disparities observed among circumpolar subpopulations. Given similarities in incidence, mortality, and risk factor prevalence across circumpolar regions, addressing disparities could benefit from coordinated international action.
Subject(s)
Stomach Neoplasms/mortality , Alaska/epidemiology , Canada/epidemiology , Female , Global Health , Humans , Incidence , Indigenous Peoples/statistics & numerical data , Male , Registries , Russia/epidemiology , Scandinavian and Nordic Countries/epidemiology , Sex DistributionABSTRACT
Among the emerging economies Brazil, Russia, India, China and South Africa (together known as the BRICS countries) share collectively approximately 40 per cent of the global population and contribute to 25 per cent of the world gross domestic products. All these countries are facing the formidable challenge of rising incidence of breast cancer and significant number of premature deaths from the disease. A multidimensional approach involving prevention, early detection and improved treatment is required to counteract the growing burden of breast cancer. A growing trend in the prevalence of major preventable risk factors of breast cancer such as obesity, western dietary habits, lack of physical activity, consumption of alcohol and smoking is contributing significantly to the rising burden of the disease in BRICS nations. Specific interventions are needed at the individual and population levels to mitigate these risk factors, preferably within the broader framework of non-communicable disease control programme. Population-based quality assured mammography-based screening of the 50-69 yr old women can reduce breast cancer mortality at least by 20 per cent. However, none of the BRICS countries have been able to implement population-based organized screening programme. Large scale opportunistic screening with mammography targeting predominantly the younger women is causing harms to the women and wasting precious healthcare resources. There are recent national recommendations to screen women with mammography in Brazil and Russia and with clinical breast examination in China (along with ultrasound) and India. Given the challenges of implementing systematic screening of the population, the BRICS countries should prioritize the early diagnosis approach and invest in educating the women about the breast cancer symptoms, training the frontline health providers to clinically detect breast cancers and appropriately refer for diagnostic confirmation, and creating improved access to good quality diagnostic and treatment facilities for breast cancer. The early diagnosis approach has been proved to achieve downstaging and improve survival at a fraction of the resources needed for population screening. The countries also need to focus on improving the services and capacity for multidisciplinary treatment of breast cancer, histopathology and immunohistochemistry, safe administration of chemotherapy and palliative care.