Modelling the effectiveness of vaccination in controlling bovine tuberculosis in wild boar

2013 ◽  
Vol 40 (5) ◽  
pp. 367 ◽  
Author(s):  
Lucy G. Anderson ◽  
Christian Gortázar ◽  
Joaquin Vicente ◽  
Michael R. Hutchings ◽  
Piran C. L. White
Keyword(s):  
Disease Control ◽  
Wild Boar ◽  
Bovine Tuberculosis ◽  
Vaccination Strategy ◽  
Control Measures ◽  
Effective Strategy ◽  
Short Term ◽  
Free Living ◽  
Western Spain

Context Bovine tuberculosis is a persistent disease of livestock in many parts of the world, especially where wildlife hosts co-exist with livestock. In south-western Spain, despite the widespread implementation of test-and-cull strategies for cattle, the herd prevalence in areas with high wild boar densities remains stable. The control of M. bovis infection in wild boar is likely to be essential for effective disease control in livestock. Methods We developed an individual-based model to evaluate whether vaccinating wild boar piglets with oral bait would be an effective strategy to reduce the prevalence of M. bovis infection in wild boar populations. Specifically, we quantified the proportion of piglets requiring vaccination and the number of years the vaccination programme would need to continue to eradicate bTB from wild boar within 25 years, comparing ‘managed’ populations on hunting estates where supplementary food is provided, with ‘unmanaged’, free-living populations. Successful vaccination was defined as the proportion of piglets that were delivered the vaccine and were effectively protected from infection. Key results Longer-term (25-year) vaccination strategies were more successful than short-term (5-year) strategies at either eradicating M. bovis or reducing it to below 90% of its original prevalence. M. bovis infection could be eradicated under a 25-year vaccination strategy if 80% of piglets were vaccinated in a managed population or 70% of piglets were vaccinated in an unmanaged population. In contrast, 5-year strategies in which 80% of piglets were vaccinated reduced the prevalence of M. bovis only by 27% or 8% in the managed and unmanaged populations, respectively. Conclusions The results of our simulation model, coupled with the promising results of initial vaccine and oral bait-uptake trials in wild boar indicated that vaccination could be an effective strategy to reduce the prevalence of M. bovis infection in wild boar if used in conjunction with other disease-control measures. Implications The vaccination of piglets over a long-term period has the potential to make an important contribution to the eradication of M. bovis infection from wild boar reservoirs in southern Spain.

scholarly journals Suitability of Different Deterrents for Short-Term Reduction of Wild Boar Contacts With Carcasses of African Swine Fever-Infected Animals

2020 ◽  
Author(s):  
Nicolai Denzin ◽  
Frithjof Helmstaedt ◽  
Carolina Probst ◽  
Franz J. Conraths
Keyword(s):  
Viral Infection ◽  
Disease Control ◽  
Wild Boar ◽  
Animal Health ◽  
African Swine Fever ◽  
Short Term ◽  
Major Threat ◽  
Physical And Chemical ◽  
Important Disease

African swine fever (ASF) is a viral infection of pigs and represents a major threat to animal health and trade. Due to the high tenacity of the causative virus also in carcasses of wild boar, contacts of wild boar with infectious carcasses are regarded an important driver of the so-called habitat cycle. The latter is believed to play a major role in maintaining the present ASF situation in wild boar in Europe. Therefore, search campaigns and timely removal and disposal of carcasses are considered important disease control approaches. If timely disposal is not feasible due to logistic reasons, deterrence of wild boar could be a provisionary option. The performance of seven deterrents (physical and chemical) was tested in a forest near Greifswald, Germany. Carcasses as entities of attraction for wild boar were substituted by luring sites. It could be demonstrated that certain physical (LED-Blinkers, aluminum stripes) and chemical (Wildschwein-Stopp™, Hukinol™) deterrents are capable of reducing significantly the odds of wild boar contacts to one third. It is recommended to carry a choice of the aforementioned, reasonable and easy to apply deterrents, when carcass search campaigns are launched in case of an outbreak of ASF in wild boar.

Short-term and long-term variability of indices related to nutritional status. I: Ca, Cu, Fe, Mg, and Zn.

1989 ◽  
Vol 35 (3) ◽  
pp. 369-373 ◽  
Author(s):  
S K Gallagher ◽  
L K Johnson ◽  
D B Milne
Keyword(s):  
Superoxide Dismutase ◽  
Nutritional Status ◽  
Iron Status ◽  
Short Term ◽  
Free Living ◽  
Analytical Technique ◽  
Metabolic Unit ◽  
Biological Component ◽  
Analytical Variation

Abstract Five free-living women (ages 28-38 y) and five women (ages 23-44 y) residing in a metabolic unit and eating a constant diet were assessed for variation in indices related to mineral nutrition. Blood was sampled once a month for five months, once a week for five weeks, and once a day for five days to assess analytical and biological variability. Analytical variability was determined by using concurrently run duplicate control samples prepared from plasma or serum pools. Of the measured indices, serum ferritin varied most, with intra-individual variance of 4.72% to 18.0%. Much of this variance may have been because of changes in iron status or in the analytical technique used. Intra-individual month-to-month variance for other indices ranged from 17% for superoxide dismutase (EC 1.15.1.1) to 1.5% for calcium. Correction for long-term analytical variation indicated that most of the variance was associated with the biological component. The higher biological variabilities of some indices, including ferritin or superoxide dismutase, need to be considered when nutritional status is being evaluated or when serial observations are made over a protracted period in clinical studies or trials.

scholarly journals Short-term, but not long-term, increased daytime workload leads to decreased night-time energetics in a free-living song bird

2019 ◽  
Vol 222 (14) ◽  
pp. jeb199513 ◽  
Author(s):  
Marcel E. Visser ◽  
Coby van Dooremalen ◽  
Barbara M. Tomotani ◽  
Andrey Bushuev ◽  
Harro A. J. Meijer ◽  
...  
Keyword(s):  
Short Term ◽  
Night Time ◽  
Free Living ◽  
Song Bird

Effect of disturbances on trophic groups in soil nematode assemblages

Nematology ◽  
2011 ◽  
Vol 13 (5) ◽  
pp. 553-559 ◽  
Author(s):  
Robert McSorley
Keyword(s):  
Plant Cover ◽  
Parasitic Nematodes ◽  
Soil Nematode ◽  
Trophic Groups ◽  
Bare Ground ◽  
Short Term ◽  
Free Living ◽  
Free Living Nematode ◽  
A Site

AbstractFree-living nematodes in soil ecosystems are vital in the decomposition of organic matter and recycling of nutrients. The effects of various types of disturbances on nematode assemblages were examined in several experiments on a single soil: a short-term detrimental disturbance from solarisation, a short-term beneficial disturbance from amendment addition, and a long-term detrimental disturbance from bare ground without plant cover. Comparison of solarised and non-solarised field plots revealed lower numbers of fungivores in solarised plots. As a result, indices involving ratios of fungivores to bacterivores and fungivores to total free-living nematodes were decreased as well. Addition of an amendment increased numbers of bacterivores. This change was also reflected in calculated indices that expressed trophic groups as percentages of the total free-living nematodes. A severely disturbed site with bare ground that was without plant cover for more than 5 years was compared with an adjacent site maintained in grass. No plant-parasitic nematodes were recovered from the bare ground site, which contained lower numbers of nematodes in all trophic groups than the grass site. However, the structure of the free-living nematode assemblages in both sites was similar, as indicated by the proportions of various trophic groups and by ratios of fungivores and bacterivores. The free-living nematode assemblage in a site with a perceived severe long-term disturbance maintained a trophic structure similar to a site with perennial plant cover.

scholarly journals Trait-Based Vaccination of Individual Meerkats (Suricata suricatta) against Tuberculosis Provides Evidence to Support Targeted Disease Control

Animals ◽  
2022 ◽  
Vol 12 (2) ◽  
pp. 192
Author(s):  
Stuart J. Patterson ◽  
Tim H. Clutton-Brock ◽  
Dirk U. Pfeiffer ◽  
Julian A. Drewe
Keyword(s):  
Disease Control ◽  
Control Strategies ◽  
Vaccination Strategy ◽  
Human Populations ◽  
Infection Rates ◽  
Survival Times ◽  
Control Groups ◽  
Free Living ◽  
Suricata Suricatta ◽  
The One

Individuals vary in their potential to acquire and transmit infections, but this fact is currently underexploited in disease control strategies. We trialled a trait-based vaccination strategy to reduce tuberculosis in free-living meerkats by targeting high-contact meerkats (socially dominant individuals) in one study arm, and high-susceptibility individuals (young subordinates) in a second arm. We monitored infection within vaccinated groups over two years comparing the results with untreated control groups. Being a member of a high-contact group had a protective effect on individuals’ survival times (Hazard Ratio = 0.5, 95% Confidence Interval, CI: 0.29–0.88, p = 0.02) compared to control groups. Over the study, odds of testing positive for tuberculosis increased more than five-fold in control groups (Odds Ratio = 5.40, 95% CI = 0.94–30.98, p = 0.058); however, no increases were observed in either of the treatment arms. Targeted disease control approaches, such as the one described in this study, allow for reduced numbers of interventions. Here, trait-based vaccination was associated with reduced infection rates and thus has the potential to offer more efficient alternatives to traditional mass-vaccination policies. Such improvements in efficiency warrant further study and could make infectious disease control more practically achievable in both animal (particularly wildlife) and human populations.

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.

scholarly journals Short-Term Economic Impact of COVID-19 on Spanish Small Ruminant Flocks

Animals ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 1357 ◽  
Author(s):  
Irene Vidaurreta ◽  
Christian de la Fe ◽  
Juan Orengo ◽  
Ángel Gómez-Martín ◽  
Bernardino Benito
Keyword(s):  
Economic Impact ◽  
Small Ruminant ◽  
Small Ruminants ◽  
Economic Consequences ◽  
Control Measures ◽  
Dairy Goat ◽  
Short Term ◽  
Using Data ◽  
Meat Market

The human pandemic COVID-19 caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) started in China in 2019 and has rapidly spread around the world, leading to extreme control measures such as population confinement and industry activity closure. Although small ruminants are not sanitary affected by this virus, the short-term economic impact derived by COVID-19 on Spanish flocks is estimated in this study, using data provided by producers and two major slaughterhouses. Milk prices of dairy goat flocks suffered a substantial drop in April 2020, close to 4.5 cts EUR/liter compared to the previous month. In contrast, the monthly milk prices in sheep remained almost stable during this period, and even increases of more than EUR 6 cts were reported in comparison with the previous year. Nevertheless, economical differences are reported by areas where producers could receive a higher income, close to EUR 0.3 per liter of milk. Global data provided by feedlots affecting 2750 Spanish flocks evidenced a lamb price drop ranging from 16.8% to 26.9% after the pandemic arrival; in line with the data directly reported by a limited sample of producers (ranging from 11.0% to 23.7%). The goat kid meat market also suffered a reduction in prices per kg, near 12.5%; although, for some flocks, losses reached up to 40%. In the same line, 2 slaughterhouses reported a sudden sacrifice drop around 27% for lambs and goat kids sacrifices in April, in contrast with the usual sacrifice figures from the beginning of 2020. Moreover, our study showed a temporary and unexpected retention of lambs and goat kids at farms due to a reduction in animals slaughtered during this period. In conclusion, data evidenced a considerable negative economic impact on Spanish small ruminant flocks, throughout the first 60 days after COVID-19’s pandemic declaration. Further studies are needed to evaluate the long-term economic consequences, in order to establish contingency plans and avoid the collapse of small ruminant industries when a crisis of these characteristics occurs.

scholarly journals Occupational Exposure Estimate of Benzene and the Effectiveness of Control Measure in Gabon’s Gasoline Storage and Distribution Facility

2018 ◽  
Vol 6 (6) ◽  
Author(s):  
Antoine Francis Obame Nguema ◽  
Akihiro Tokai ◽  
Ibnu Susanto Joyosemito ◽  
Naoya Kojima
Keyword(s):  
Occupational Exposure ◽  
Control Measure ◽  
Control Measures ◽  
Exposure Level ◽  
Short Term ◽  
High Exposure ◽  
Exposure Estimate ◽  
Benzene Concentration ◽  
Vapor Emissions

The processing of petroleum products in gasoline storage and distribution facility for loading operation, has caused the generation of vapor emissions sources. Benzene is one of those vapor emissions that workers are likely to be exposed at high exposure level during conducting out specific tasks such as loading gasoline to various petroleum storage transport modes. This results in many problems on human health such as cancer and non-cancer diseases. However, the estimate of benzene exposure to indicate the control measures has not been fully explored in previous researches. In this study, the occupational exposure estimate of benzene in Gabon’s gasoline storage and distribution facility was investigated by using a quantitative and predictive exposure inhalation model; to estimate benzene concentration before and after applying control measures. The results indicate that the benzene concentrations varied between 9.46 mg/m³ and 187 mg/m³ for short term and has the value of 187 mg/m³ for long term. The implementation of control measures including using vapor recovery system, chemical filter mask and improving worker’s behavior might contribute to significantly reduce benzene concentration to the range of 4.52 – 29.08 mg/m³ for short term and down to 4.55 mg/m³ for long term. This almost meets the Agency Governmental Industrial Hygienists standard, in which occupational exposure limit for short term and long term exposure is 8.1 mg/m³ and 3.16 mg/m³, respectively.

scholarly journals Impact of different control policies for COVID-19 outbreak on the air transportation industry: A comparison between China, the U.S. and Singapore

PLoS ONE ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. e0248361
Author(s):  
Fanyu Meng ◽  
Wenwu Gong ◽  
Jun Liang ◽  
Xian Li ◽  
Yiping Zeng ◽  
...  
Keyword(s):  
Human Mobility ◽  
Air Transportation ◽  
International Travel ◽  
Control Measures ◽  
Air Cargo ◽  
Transportation Industry ◽  
Short Term ◽  
Freight Traffic ◽  
The U.S

Many countries have been implementing various control measures with different strictness levels to prevent the coronavirus disease 2019 (COVID-19) from spreading. With the great reduction in human mobility and daily activities, considerable impacts have been imposed on the global air transportation industry. This study applies a hybrid SARIMA-based intervention model to measure the differences in the impacts of different control measures implemented in China, the U.S. and Singapore on air passenger and air freight traffic. To explore the effect of time span for the measures to be in force, two scenarios are invented, namely a long-term intervention and a short-term intervention, and predictions are made till the end of 2020 for all three countries under both scenarios. As a result, predictive patterns of the selected metrics for the three countries are rather different. China is predicted to have the mildest economic impact on the air transportation industry in this year in terms of air passenger revenue and air cargo traffic, provided that the control measures were prompt and effective. The U.S. would suffer from a far-reaching impact on the industry if the same control measures are maintained. More uncertainties are found for Singapore, as it is strongly associated with international travel demands. Suggestions are made for the three countries and the rest of the world on how to seek a balance between the strictness of control measures and the potential long-term industrial losses.

scholarly journals Empirical model for short-time prediction of COVID-19 spreading

2020 ◽  
Vol 16 (12) ◽  
pp. e1008431
Author(s):  
Martí Català ◽  
Sergio Alonso ◽  
Enrique Alvarez-Lacalle ◽  
Daniel López ◽  
Pere-Joan Cardona ◽  
...  
Keyword(s):  
Health Workers ◽  
Gompertz Model ◽  
Control Measures ◽  
Short Term ◽  
Spreading Velocity ◽  
Current State ◽  
Term Evolution ◽  
Public Health Workers ◽  
Short Time

The appearance and fast spreading of Covid-19 took the international community by surprise. Collaboration between researchers, public health workers, and politicians has been established to deal with the epidemic. One important contribution from researchers in epidemiology is the analysis of trends so that both the current state and short-term future trends can be carefully evaluated. Gompertz model has been shown to correctly describe the dynamics of cumulative confirmed cases, since it is characterized by a decrease in growth rate showing the effect of control measures. Thus, it provides a way to systematically quantify the Covid-19 spreading velocity and it allows short-term predictions and longer-term estimations. This model has been employed to fit the cumulative cases of Covid-19 from several European countries. Results show that there are systematic differences in spreading velocity among countries. The model predictions provide a reliable picture of the short-term evolution in countries that are in the initial stages of the Covid-19 outbreak, and may permit researchers to uncover some characteristics of the long-term evolution. These predictions can also be generalized to calculate short-term hospital and intensive care units (ICU) requirements.

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