scholarly journals Serological surveillance of noroviruses in a community-based prospective cohort: a study protocol

BMJ Open ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. e043228
Author(s):  
Lu Wang ◽  
Dongjie Xie ◽  
Jingrong Yu ◽  
Mark Momoh Koroma ◽  
Mengsi Qiu ◽  
...  
Keyword(s):  
Prospective Cohort ◽  
Herd Immunity ◽  
Age Groups ◽  
Northern China ◽  
Oil Field ◽  
Blood Collection ◽  
Sociodemographic Characteristics ◽  
Blood Group Antigens ◽  
Community Based ◽  
Serological Surveillance

IntroductionNoroviruses are the leading cause of viral acute gastroenteritis affecting all age groups. Since 2014, the previous rarely reported GII.P17-GII.17 and recombinant GII.P16-GII.2 norovirus emerged, replacing GII.4 predominant genotype, causing increased outbreaks in China and other countries. Meanwhile, GII.4/2012 Sydney strain has re-emerged as the dominant variant in many places in 2015–2018. The role of herd immunity as the driving force during these new emerging or re-emerging noroviruses is poorly defined. Serological surveillance studies on community-based prospective cohort on norovirus are highly needed.Methods and analysesThis study will include 1000 out of 9798 participants aged 18 years and above from Caofeidian district, Tangshan city, northern China. Baseline data on sociodemographic characteristics and blood samples were collected in 2013–2014. Blood collection will be replicated annually throughout the cohort until 2023. Saliva samples were also collected in 2016. The seroprevalence and seroincidence of blockade antibodies against norovirus genotypes of GII.P17-GII.17, GII.P16-GII.2, the re-emerged GII.4/2012 and potential novel pandemic variants will be evaluated by ELISA. Associations between genotype blockade antibodies and sociodemographic factors and human histo-blood group antigens will be evaluated using univariate and multivariate analysis. The dynamics of herd immunity duration will be estimated in this longitudinal surveillance.Ethics and disseminationThe study has been approved by the Ethical Committees of the Staff Hospital of Jidong oil-field of China National Petroleum Corporation. This study will provide insight into the seroprevalence and seroincidence of noroviruses, and their relationships with sociodemographic characteristics and genetic susceptibility. It will also explain herd immunity of the emerged and re-emerged genotypes or variants. The study will further enable an understanding of the mechanism driving the replacement of norovirus genotypes. Research findings will be disseminated in peer-reviewed journals and at scientific meetings.

scholarly journals Community-Based Seroprevalence of SARS-CoV-2 Antibodies following the First Wave of the COVID-19 Pandemic in Jazan Province, Saudi Arabia

2021 ◽  
Vol 18 (23) ◽  
pp. 12451
Author(s):  
Abdulaziz Alhazmi ◽  
Edrous Alamer ◽  
Siddig Abdelwahab ◽  
Nizar Khamjan ◽  
Abdullah Hamami ◽  
...  
Keyword(s):  
Saudi Arabia ◽  
Herd Immunity ◽  
Age Groups ◽  
Population Based ◽  
Control Measures ◽  
Community Based ◽  
Significant Difference ◽  
High Prevalence ◽  
Serological Data ◽  
Older Populations

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to spread globally, causing unprecedented effects on global health and economies. Community-based serological data are essential for understanding the true prevalence of infections, specifically the subclinical infections, as COVID-19 asymptomatic infections are common. Such data would also be important for decision making around choosing appropriate epidemiological control measures, as well as for the true estimation of mortality rates in the population. Further, determining the seroprevalence of anti-SARS-CoV-2 antibodies in the population would provide important information on herd immunity. In this study, we conducted a population-based age-stratified serological study to understand the prevalence of SARS-CoV-2 in Jazan Province, Saudi Arabia. Out of 594 participants who were recruited from 29 August to 30 December 2020, just before the vaccination rollout program in Saudi Arabia, about 157 were seropositive for SARS-CoV-2, indicating an estimated seropositivity rate of 26%. Although no significant difference in seropositivity was seen between male and female participants, we found that lower seroprevalence was associated with the younger (below 18 years old) and older populations (older than 56 years) compared with other age groups (19–55 years). These data indicate a high prevalence of SARS-CoV-2 antibodies following the peak of COVID-19 spread in Jazan province; however, most of the population (three-quarters) remains susceptible to SARS-CoV-2 infection.

scholarly journals The Use of GIS Technology to Optimize COVID-19 Vaccine Distribution: A Case Study of the City of Warsaw, Poland

2021 ◽  
Vol 18 (11) ◽  
pp. 5636
Author(s):  
Sylwia Krzysztofowicz ◽  
Katarzyna Osińska-Skotak
Keyword(s):  
Herd Immunity ◽  
Research Work ◽  
Age Groups ◽  
Group Living ◽  
Population Group ◽  
Gis Technology ◽  
Vaccination Site ◽  
Global Challenge ◽  
Vaccine Distribution ◽  
The City

The COVID-19 pandemic is a global challenge, and the key to tackling it is vaccinating a specified percentage of the population to acquire herd immunity. The observed problems with the efficiency of the vaccination campaigns in numerous countries around the world, as well as the approach used at the initial stage of the National Immunization Program in Poland, prompted us to analyse the possibility of using GIS technology to optimize the distribution of vaccines to vaccination sites so as to minimize the period needed to vaccinate individual population groups. The research work was carried out on the example of Warsaw, the capital of Poland and the city with the largest population in the country. The analyses were carried out for the 60–70 and 50–60 age groups, in various approaches and for vaccines of different companies (Moderna, BioNTech, AstraZeneca), used to vaccinate people in Poland. The proposed approach to optimize vaccine distribution uses Thiessen’s tessellation to obtain information on the number of people in a given population group living in the area of each vaccination site, and then to estimate the time needed to vaccinate that group. Compared to the originally used vaccination scenario with limited availability of vaccines, the proposed approach allows practitioners to design fast and efficient distribution scenarios. With the developed methodology, we demonstrated ways to achieve uniform vaccination coverage throughout the city. We anticipate that the proposed approach can be easily automated and broadly applied to various urban settings.

The clinical utility of accurate NAFLD ultrasound grading: Results from a community-based, prospective cohort study

2021 ◽  
Vol 136 ◽  
pp. 109516
Author(s):  
Madunil Anuk Niriella ◽  
Dileepa Senajith Ediriweera ◽  
Anuradhani Kasturiratne ◽  
Deepa Gunasekara ◽  
Shamila Thivanshi De Silva ◽  
...  
Keyword(s):  
Cohort Study ◽  
Prospective Cohort Study ◽  
Prospective Cohort ◽  
Clinical Utility ◽  
Community Based

scholarly journals Village-to-village screening for hepatitis B and C using quantitative HBsAg and anti-HCV testing with reflex HCV core antigen tests in the remote communities of a resource-rich setting: a population-based prospective cohort study

BMJ Open ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. e046115
Author(s):  
Te-Sheng Chang ◽  
Kao-Chi Chang ◽  
Wei-Ming Chen ◽  
Nien-Tzu Hsu ◽  
Chih-Yi Lee ◽  
...  
Keyword(s):  
Cohort Study ◽  
Hepatitis B ◽  
Prospective Cohort Study ◽  
Prospective Cohort ◽  
Population Based ◽  
Core Antigen ◽  
Remote Communities ◽  
Community Based ◽  
Patient Allocation ◽  
Hcv Testing

ObjectivesCommunity-based screening for hepatitis B virus (HBV) and hepatitis C virus (HCV) is essential for hepatitis elimination. This study attempted to increase screening accessibility and efficacy by using alternative tools.DesignPopulation-based prospective cohort study.SettingHepatitis elimination program at Yunlin County, Taiwan.ParticipantsAll 4552 individuals participated in 60 screening sessions of a community-based HBV and HCV screening project in five rural townships with approximately 95 000 inhabitants in central-western Taiwan.InterventionsTo increase accessibility, 60 outreach screening sessions were conducted in 41 disseminative sites. Quantitative HBV surface antigen (qHBsAg) and anti-HCV testing with reflex HCV core antigen (HCV Ag) tests were employed as alternative screening tools.Main outcome measuresCalculate village-specific prevalence of HBsAg, anti-HCV and HCV Ag and establish patient allocation strategies according to levels of qHBsAg HCV Ag and alanine aminotransferase (ALT).ResultsOf 4552 participants, 553, 697 and 290 were positive for HBsAg, anti-HCV and HCV Ag, respectively; 75 of them had both HBsAg and anti-HCV positivity. The average (range) number of participants in each screening session was 98 (31–150). The prevalence rates (range) of HBsAg, anti-HCV and HCV Ag were 12.1% (4.3%–19.4%), 15.3% (2.6%–52.3%) and 6.4% (0%–30.2%), respectively. The HCV Ag positivity rate among anti-HCV-positive participants was 42% (0%–100%). Using cut-off values of >200 IU/mL for qHBsAg, >3 fmol/L for HCV Ag and >40 IU/mL for ALT as criteria for patient referral, we noted an 80.2% reduction in referral burden. Three villages had high anti-HCV prevalences of 52.3%, 53.8% and 63.4% with corresponding viraemic prevalences of 23.2%, 30.1% and 22% and thus constituted newly identified HCV-hyperendemic villages.ConclusionOutreach hepatitis screening increases accessibility for residents in rural communities. Screening HBV and HCV through qHBsAg and HCV Ag tests provides information concerning viral activities, which might be conducive to precise patient allocation in remote communities.

Age Differences in Life Events: A Multivariate Controlled Analysis

1988 ◽  
Vol 27 (3) ◽  
pp. 207-220 ◽  
Author(s):  
Dana C. Hughes ◽  
Dan G. Blazer ◽  
Linda K. George
Keyword(s):  
North Carolina ◽  
Life Events ◽  
Age Differences ◽  
Catchment Area ◽  
Age Groups ◽  
Community Survey ◽  
Personal Interview ◽  
Community Based ◽  
Loved One ◽  
The Past

Effects of age on the distribution of specific life events experienced during the past year by community-based adults were examined controlling for sex, race, education, marital status, and place of residence. The controlled analyses were done using logistic regression. Data were gathered via personal interview from 3,798 respondents ages eighteen years and over who participated in the Epidemiologic Catchment Area (ECA), community survey from North Carolina. Respondents were placed in one of four age groups. The percentage of respondents reporting each of the nineteen events examined ranged from 0.5 percent for death of spouse to 19.1 percent for death of loved one. Age was an important predictor in the controlled analysis for thirteen of the seventeen life events examined. A majority of differences occurred between the youngest and oldest age groups. Age differences were not found for illness of one week or more involving activity limitation.

scholarly journals Cataract among elderly in Sri Lanka

2019 ◽  
Author(s):  
A.A. Nilanga Nishad ◽  
S.A. Hewage ◽  
K. Arulmoly ◽  
M.S. Amaratunge ◽  
J de Silva ◽  
...  
Keyword(s):  
Sri Lanka ◽  
Screening Programme ◽  
National Level ◽  
Age Groups ◽  
Cross Sectional Study ◽  
Community Based ◽  
Cross Sectional ◽  
Future Studies ◽  
Factors Associated ◽  
Younger Age

AbstractOut of 39 billion people who are blind around the world, 20 billion (51.3%) is due to cataract, which is preventable. This study intended to assess the prevalence and factors associated with cataract among elderly in a divisional secretariat area in Sri Lanka. This community based cross sectional study assessed randomly selected470 adults over 60 years of age. Diagnosis of cataract was made by a slit lamp examination by medical officers, and classified according to Oxford Lens Opacity Classification system (LOCS III). Majority was between 60-69 age groups and 71% was females. The prevalence of cataract was estimated to be 80.6% including operated eye and 73.6% excluding the operated eye, with a female preponderance in lower age categories. Commonest type of cataract was the nuclear type (n=422; 44.9%), with a majority in grade 2 (218; 23.2%). The prevalence of cataract surgery in the diseased population was as low as 7%. Cataract leading to blindness is very prevalent among adults over 60 years of age in the studied area. Females tend to develop the disease at an early age than males. These findings warrant screening programme for elderly at community level, targeting females at a younger age than males. Future studies are recommended to assess the coverage and barriers for cataract surgeries at national level, which would be immensely useful in planning and improving health services.

scholarly journals Prevalence of eczema among older persons: A population-based cross-sectional study

2021 ◽  
Vol 0 ◽  
pp. 1-5
Author(s):  
Vijayan Neena ◽  
Neelakandhan Asokan ◽  
Rajany Jose ◽  
A. Sarin
Keyword(s):  
Older Persons ◽  
Health Workers ◽  
Age Groups ◽  
Medical Knowledge ◽  
Population Based ◽  
Cross Sectional Survey ◽  
Community Based Interventions ◽  
Community Based ◽  
Cross Sectional ◽  
Lichen Simplex Chronicus

Background: There are very few population-based studies on the prevalence of eczema among older persons Aims: To estimate the prevalence and types of eczema in those aged 65 years or more in the community and to evaluate the effectiveness of community-based interventions for case finding. Methods: In the first stage of this cross-sectional survey, trained health workers of a non-governmental organization surveyed the eligible population and identified persons likely to have eczema. In the second stage, dermatologists examined such persons to ascertain the diagnosis. Statistical analysis was done using Epi Info software version 7. Prevalence of eczema was expressed in percentages. Chi-square test was used for comparing the difference in prevalence of eczema in various age groups and sex. Results: Health workers identified 98 persons as possible cases of eczema after interviewing 385 older persons in the community. Among them 95 persons were examined by dermatologists and 44 were confirmed to have eczema (diagnostic accuracy of health workers = 46.3%).Point prevalence of eczema was 11.4% (44/385). Prevalence was similar in males and females. It was greater (18.2 %) among persons aged 81 years or more. Asteatotic eczema, gravitational eczema and lichen simplex chronicus were the more common types of eczema. Limitations: Possible underestimation of the prevalence rates due to limited medical knowledge of health workers; limited facilities for examination and investigations at the medical camps and home visits. Conclusion: There appears to be a considerable burden of eczema among older persons in the community. A community-based approach involving non-governmental organizations has the potential to identify cases and offer care close to their homes.

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