scholarly journals Exploiting Scanning Surveillance Data to Inform Future Strategies for the Control of Endemic Diseases: The Example of Sheep Scab

2021 ◽  
Vol 8 ◽  
Author(s):  
Eilidh Geddes ◽  
Sibylle Mohr ◽  
Elizabeth Sian Mitchell ◽  
Sara Robertson ◽  
Anna M. Brzozowska ◽  
...  
Keyword(s):  
Great Britain ◽  
Disease Control ◽  
Animal Health ◽  
Skills Training ◽  
Surveillance Data ◽  
Control Measures ◽  
Positive Skin ◽  
Sheep Scab ◽  
Endemic Diseases ◽  
The Impact

Scanning surveillance facilitates the monitoring of many endemic diseases of livestock in Great Britain, including sheep scab, an ectoparasitic disease of major welfare and economic burden. There is, however, a drive to improve the cost-effectiveness of animal health surveillance, for example by thoroughly exploiting existing data sources. By analysing the Veterinary Investigation Diagnosis Analysis (VIDA) database, this study aimed to enhance the use of existing scanning surveillance data for sheep scab to identify current trends, highlighting geographical “hotspots” for targeted disease control measures, and identifying a denominator to aid the interpretation of the diagnostic count data. Furthermore, this study collated and assessed the impact of past targeted disease control initiatives using a temporal aberration detection algorithm, the Farrington algorithm, to provide an evidence base towards developing cost-effective disease control strategies. A total of 2,401 positive skin scrapes were recorded from 2003 to 2018. A statistically significant decline in the number of positive skin scrapes diagnosed (p < 0.001) occurred across the study period, and significant clustering was observed in Wales, with a maximum of 47 positive scrapes in Ceredigion in 2007. Scheduled ectoparasite tests was also identified as a potential denominator for the interpretation of positive scrapes by stakeholders. Across the study period, 11 national disease control initiatives occurred: four in Wales, three in England, and four in Scotland. The majority (n = 8) offered free diagnostic testing while the remainder involved knowledge transfer either combined with free testing or skills training and the introduction of the Sheep Scab (Scotland) Order 2010. The Farrington algorithm raised 20 alarms of which 11 occurred within a period of free testing in Wales and one following the introduction of the Sheep Scab (Scotland) Order 2010. In summary, our analysis of the VIDA database has greatly enhanced our knowledge of sheep scab in Great Britain, firstly by identifying areas for targeted action and secondly by offering a framework to measure the impact of future disease control initiatives. Importantly this framework could be applied to inform future strategies for the control of other endemic diseases.

scholarly journals Real-time estimation of the influenza-associated excess mortality in Hong Kong

2019 ◽  
Vol 147 ◽  
Author(s):  
Jessica Y. Wong ◽  
Edward Goldstein ◽  
Vicky J. Fang ◽  
Benjamin J. Cowling ◽  
Peng Wu
Keyword(s):  
Hong Kong ◽  
Real Time ◽  
Excess Mortality ◽  
Time Estimation ◽  
Surveillance Data ◽  
Control Measures ◽  
Influenza Surveillance ◽  
Mortality Data ◽  
Real Time Estimation ◽  
The Impact

Abstract Statistical models are commonly employed in the estimation of influenza-associated excess mortality that, due to various reasons, is often underestimated by laboratory-confirmed influenza deaths reported by healthcare facilities. However, methodology for timely and reliable estimation of that impact remains limited because of the delay in mortality data reporting. We explored real-time estimation of influenza-associated excess mortality by types/subtypes in each year between 2012 and 2018 in Hong Kong using linear regression models fitted to historical mortality and influenza surveillance data. We could predict that during the winter of 2017/2018, there were ~634 (95% confidence interval (CI): (190, 1033)) influenza-associated excess all-cause deaths in Hong Kong in population ⩾18 years, compared to 259 reported laboratory-confirmed deaths. We estimated that influenza was associated with substantial excess deaths in older adults, suggesting the implementation of control measures, such as administration of antivirals and vaccination, in that age group. The approach that we developed appears to provide robust real-time estimates of the impact of influenza circulation and complement surveillance data on laboratory-confirmed deaths. These results improve our understanding of the impact of influenza epidemics and provide a practical approach for a timely estimation of the mortality burden of influenza circulation during an ongoing epidemic.

scholarly journals Bovine Babesiosis in Turkey: Impact, Current Gaps, and Opportunities for Intervention

Pathogens ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 1041
Author(s):  
Sezayi Ozubek ◽  
Reginaldo G. Bastos ◽  
Heba F. Alzan ◽  
Abdullah Inci ◽  
Munir Aktas ◽  
...  
Keyword(s):  
Vaccine Development ◽  
Point Of Care ◽  
Animal Health ◽  
Current Control ◽  
Diagnostic Methods ◽  
Control Measures ◽  
Bovine Babesiosis ◽  
Research Programs ◽  
The Impact

Bovine babesiosis is a global tick-borne disease that causes important cattle losses and has potential zoonotic implications. The impact of bovine babesiosis in Turkey remains poorly characterized, but several Babesia spp., including B. bovis, B. bigemina, and B. divergens, among others and competent tick vectors, except Rhipicephalus microplus, have been recently identified in the country. Bovine babesiosis has been reported in all provinces but is more prevalent in central and highly humid areas in low and medium altitude regions of the country housing approximately 70% of the cattle population. Current control measures include acaricides and babesicidal drugs, but not live vaccines. Despite the perceived relevant impact of bovine babesiosis in Turkey, basic research programs focused on developing in vitro cultures of parasites, point-of-care diagnostic methods, vaccine development, “omics” analysis, and gene manipulation techniques of local Babesia strains are scarce. Additionally, no effective and coordinated control efforts managed by a central animal health authority have been established to date. Development of state-of-the-art research programs in bovine babesiosis to address current gaps in knowledge and implementation of long-term plans to control the disease will surely result in important economic, nutritional, and public health benefits for the country and the region.

scholarly journals The impact of contact structure on infectious disease control: influenza and antiviral agents

2007 ◽  
Vol 135 (7) ◽  
pp. 1124-1132 ◽  
Author(s):  
H.-P. DUERR ◽  
M. SCHWEHM ◽  
C. C. LEARY ◽  
S. J. De Vlas ◽  
M. EICHNER
Keyword(s):  
Disease Control ◽  
Contact Structure ◽  
Influenza Pandemic ◽  
Antiviral Treatment ◽  
Antiviral Agents ◽  
Emerging Infectious Diseases ◽  
Control Measures ◽  
Variable Degree ◽  
Contact Patterns ◽  
The Impact

SUMMARYPlanning adequate public health responses against emerging infectious diseases requires predictive tools to evaluate the impact of candidate intervention strategies. With current interest in pandemic influenza very high, modelling approaches have suggested antiviral treatment combined with targeted prophylaxis as an effective first-line intervention against an emerging influenza pandemic. To investigate how the effectiveness of such interventions depends on contact structure, we simulate the effects in networks with variable degree distributions. The infection attack rate can increase if the number of contacts per person is heterogeneous, implying the existence of high-degree individuals who are potential super-spreaders. The effectiveness of a socially targeted intervention suffers from heterogeneous contact patterns and depends on whether infection is predominantly transmitted to close or casual contacts. Our findings imply that the various contact networks' degree distributions as well as the allocation of contagiousness between close and casual contacts should be examined to identify appropriate strategies of disease control measures.

scholarly journals The African swine fever control zone in South Africa and its current relevance

2016 ◽  
Vol 83 (1) ◽  
Author(s):  
Noluvuyo R. Magadla ◽  
Wilna Vosloo ◽  
Livio Heath ◽  
Bruce Gummow
Keyword(s):  
South Africa ◽  
Disease Control ◽  
African Swine Fever ◽  
Control Measures ◽  
Maximum Temperature ◽  
Boundary Line ◽  
Control Line ◽  
Control Zone ◽  
Ornithodoros Moubata ◽  
The Impact

African swine fever (ASF) has been reported in South Africa since the early 20th century. The disease has been controlled and confined to northern South Africa over the past 80 years by means of a well-defined boundary line, with strict control measures and movement restrictions north of this line. In 2012, the first outbreak of ASF outside the ASF control zone since 1996 occurred. The objective of this study was to evaluate the current relevance of the ASF control line as a demarcation line between endemic ASF (north) areas and ASF-free (south) area and to determine whether there was a need to realign its trajectory, given the recent outbreaks of ASF, global climate changes and urban development since the line’s inception. A study of ASF determinants was conducted in an area 20 km north and 20 km south of the ASF control line, in Limpopo, Mpumalanga, North West and Gauteng provinces between May 2008 and September 2012. The study confirmed that warthogs, warthog burrows and the soft tick reservoir, Ornithodoros moubata, are present south of the ASF control line, but no virus or viral DNA was detected in these ticks. There appears to be an increasing trend in the diurnal maximum temperature and a decrease in humidity along the line, but the impact of these changes is uncertain. No discernible changes in minimum temperatures and average rainfall along the disease control line were observed between 1992 and 2014. Even though the reservoirs were found south of the ASF boundary line, the study concluded that there was no need to realign the trajectory of the ASF disease control line, with the exception of Limpopo Province. However, the provincial surveillance programmes for the reservoir, vector and ASF virus south of this line needs to be maintained and intensified as changing farming practices may favour the spread of ASF virus beyond the control line.Keywords: African swine fever; warthog burrow; Ornithodoros moubata;control line

scholarly journals Survey of protozoan vector-borne diseases in dogs from Atlantic Rainforest fragment around Billings Dam, São Paulo, Brazil

2020 ◽  
Vol 50 (9) ◽  
Author(s):  
Roberta Carvalho de Freitas e Azevedo ◽  
Giovanna Stefani Nosberto Castelli ◽  
Ryan Emiliano da Silva ◽  
Jaciara de Oliveira Jorge Costa ◽  
Renata Tonhosolo ◽  
...  
Keyword(s):  
Animal Health ◽  
Companion Animals ◽  
Sao Paulo ◽  
Control Measures ◽  
Molecular Diagnostic ◽  
São Paulo ◽  
Vector Borne Diseases ◽  
Babesia Vogeli ◽  
Vector Borne ◽  
The Impact

ABSTRACT: Vector-borne diseases are currently one of the biggest public health concerns worldwide. Dogs, being the closest companion animals to humans, are considered the main reservoir of some of these diseases in the urban environment. Therefore, the study of the disease behavior in dogs can help to understand the disease affecting human health. Serological and molecular diagnoses of Babesia vogeli, Rangelia vitalli, Leishmania infantum, and other trypanosomatids, were performed by immunochromatographic and PCR assays, respectively, on dogs in a dog shelter located in an Atlantic Forest fragment near the Billings Dam, São Bernardo do Campo, São Paulo-Brazil. Our molecular diagnostic results showed a high prevalence of Babesia vogeli, at 20.9% (17/81). No other protozoan was detected in any of the tests. Determining the prevalence of major vector-borne diseases is essential to establish preventive and control measures for zoonotic diseases in animals kept in shelters, in order to minimize the impact of vector-borne diseases on animal health.

scholarly journals Individually Optimal Choices can be Collectively Disastrous in COVID-19 Disease Control

2021 ◽  
Author(s):  
Madison Stoddard ◽  
Debra Van Egeren ◽  
Kaitlyn Johnson ◽  
Smriti Rao ◽  
Josh Furgeson ◽  
...  
Keyword(s):  
Public Health ◽  
Disease Control ◽  
Control Measures ◽  
Disease Spread ◽  
Complete Suppression ◽  
Natural Immunity ◽  
Endemic Disease ◽  
Health Measures ◽  
The Impact

Abstract Background: The word ‘pandemic’ conjures dystopian images of bodies stacked in the streets and societies on the brink of collapse. Despite this frightening picture, denialism and noncompliance with public health measures are common in the historical record, for example during the 1918 Influenza pandemic or the 2015 Ebola epidemic. The unique characteristics of SARS-CoV-2—its high basic reproduction number (R0), time-limited natural immunity and considerable potential for asymptomatic spread—exacerbate the public health repercussions of noncompliance with interventions (such as vaccines and masks) to limit disease transmission. Our work explores the rationality and impact of noncompliance with COVID-19 disease control measures. Methods: In this work, we used game theory to explore when noncompliance confers a perceived benefit to individuals. We then used epidemiological modeling to predict the impact of noncompliance on control of COVID-19, demonstrating that the presence of a noncompliant subpopulation prevents suppression of disease spread. Results: Our modeling demonstrating that noncompliance is a Nash equilibrium under a broad set of conditions, and that the existence of a noncompliant population can result in extensive endemic disease in the long-term after a return to pre-pandemic social and economic activity. Endemic disease poses a threat for both compliant and noncompliant individuals; all community members are protected if complete suppression is achieved, which is only possible with a high degree of compliance. For interventions that are highly effective at preventing disease spread, however, the consequences of noncompliance are borne disproportionately by noncompliant individuals. Conclusions: In sum, our work demonstrates the limits of free-market approaches to compliance with disease control measures during a pandemic. The act of noncompliance with disease intervention measures creates a negative externality, rendering COVID-19 disease control ineffective in the short term and making complete suppression impossible in the long term. Our work underscores the importance of developing effective strategies for prophylaxis through public health measures aimed at complete suppression and the need to focus on compliance at a population level.

MODELING CHOLERA TRANSMISSION UNDER DISEASE CONTROL MEASURES

2020 ◽  
pp. 1-26
Author(s):  
MARGARET BROWN ◽  
MIKO JIANG ◽  
CHAYU YANG ◽  
JIN WANG
Keyword(s):  
Disease Control ◽  
Disease Transmission ◽  
Control Measures ◽  
Transmission Dynamics ◽  
Threshold Dynamics ◽  
Education Programs ◽  
Multiple Control ◽  
Indirect Transmission ◽  
Transmission Pathways ◽  
The Impact

We present a new mathematical model to investigate the transmission dynamics of cholera under disease control measures that include education programs and water sanitation. The model incorporates the impact of education programs into the disease transmission rates and that of water sanitation into the environmental pathogen dynamics. We conduct a detailed analysis to the autonomous system of the model and establish the local and global stabilities of its equilibria that characterize the threshold dynamics of cholera. We then perform an optimal control study on the general model with time-dependent controls and explore effective approaches to implement the education programs and water sanitation while balancing their costs. Our analysis and simulation highlight the complex interaction among the direct and indirect transmission pathways of the disease, the intrinsic growth of the environmental pathogen and the impact of multiple control measures, and their roles in collectively shaping the transmission dynamics of cholera.

scholarly journals Will there be any more classical scrapie cases in sheep in Great Britain? A modelling study to predict future cases

2020 ◽  
Vol 148 ◽  
Author(s):  
M.E. Arnold ◽  
B. Rajanayagam
Keyword(s):  
Great Britain ◽  
Time Frame ◽  
Calculation Model ◽  
Classical Scrapie ◽  
Surveillance Data ◽  
Control Measures ◽  
Effective Control ◽  
Back Calculation ◽  
Low Probability ◽  
Rate Of Decline

Abstract The aim of this study was to apply a back-calculation model to Great Britain (GB) classical scrapie surveillance data, and use this model to estimate how many more cases might be expected, and over what time frame these cases might occur. A back-calculation model was applied to scrapie surveillance data between 2005 and 2019 to estimate the annual rate of decline of classical scrapie. This rate was then extrapolated to predict the number of future cases each year going forward. The model shows that there may be yet further cases of classical scrapie in GB. These will most likely occur in the fallen stock scheme, with approximately a 25% probability of at least 1 further scrapie positive, with a very low probability (~0.2%) of having up to three additional scrapie positives. This highlights the difficulty of completely eliminating all further cases, even in the presence of very effective control measures.

Costs of the major endemic diseases of sheep in Great Britain and the potential benefits of reduction in disease impact

2005 ◽  
Vol 81 (1) ◽  
pp. 23-29 ◽  
Author(s):  
G. J. Nieuwhof ◽  
S. C. Bishop
Keyword(s):  
Great Britain ◽  
Preventive Measures ◽  
Intestinal Parasites ◽  
The Other ◽  
Sheep Scab ◽  
Endemic Diseases ◽  
Disease Costs ◽  
Potential Benefits ◽  
Disease Impact ◽  
Proportional Effect

AbstractThe costs of three major endemic sheep diseases in Great Britain, gastro-intestinal (GI) parasites, footrot and scab, were estimated and compared with costs for other diseases from another study. Disease costs include lost performance, preventive measures and treatment of affected animals. The most costly disease, of those studied, for the British sheep industry is infestation with GI parasites, with estimated annual costs of £84 million. Annual costs for the other two diseases are £24 million for footrot and £8 million for sheep scab. This compares with literature estimates of £20 million for Chlamydial abortions and £12 million for toxoplasmosis. For sheep scab most costs are for preventive measures, therefore, short of eradication, a reduction in incidence will have a limited effect on costs. For GI parasites, costs are linearly related to the severity of the infestation and a reduction of the disease will have a proportional effect on the costs to the industry. For footrot about half the costs are for preventive measures, the other half is for lost production and treatment. A reduction in the incidence of footrot has a proportional effect on the £10 million associated with loss of production and treatment of infected animals. It is concluded that gastro-intestinal parasites and footrot are two sheep diseases in Britain for which a reduction of severity or incidence will have a large impact on costs of production.

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