The combination of targeted vaccination and ring vaccination

2021 ◽  
Vol 31 (6) ◽  
pp. 063108
Author(s):  
Weiqiang Li ◽  
Jin Zhou ◽  
Zhen Jin ◽  
Jun-an Lu
Keyword(s):  
Ring Vaccination

scholarly journals Being Pregnant during the Kivu Ebola Virus Outbreak in DR Congo: The rVSV-ZEBOV Vaccine and Its Accessibility by Mothers and Infants during Humanitarian Crises and in Conflict Areas

Vaccines ◽  
2020 ◽  
Vol 8 (1) ◽  
pp. 38 ◽  
Author(s):  
David A. Schwartz
Keyword(s):  
Ebola Virus ◽  
Virus Disease ◽  
Humanitarian Assistance ◽  
Lactating Women ◽  
Conflict Zone ◽  
Ring Vaccination ◽  
Humanitarian Crises ◽  
Republic Of The Congo ◽  
Violent Acts ◽  
Very High

The Ebola virus disease (EVD) outbreak that began in Kivu province of the Democratic Republic of the Congo (DRC) in July 2018 is the second largest in history. It is also the largest and most deadly of the ten Ebola outbreaks to occur in DRC, the country where Ebola was first identified during the 1976 Yambuku outbreak. The Kivu region is one of the most challenging locations in which to organize humanitarian assistance. It is an active conflict zone in which numerous armed groups are conducting violent acts, often directed against the inhabitants, healthcare and relief workers and peacekeepers. EVD has been especially problematic in pregnancy—previous outbreaks both in DRC and other countries have resulted in very high mortality rates among pregnant women and especially their infants, with maternal mortality in some outbreaks reaching over 90% and perinatal mortality 100%. The development and implementation of the Merck rVSV-ZEBOV vaccine for Ebola infection has been a tremendous public health advance in preventing EVD, being used successfully in both the West Africa Ebola epidemic and the Équateur DRC Ebola outbreak. But from the start of the Kivu outbreak, policy decisions had resulted in excluding pregnant and lactating women and their infants from receiving it during extensive ring vaccination efforts. In June 2019, this policy was reversed, 10 months after the start of the outbreak. Pregnant and lactating women are now permitted not only the rVSV-ZEBOV vaccine in the continuing Kivu outbreak but also the newly implemented Ad26.ZEBOV/MVA-BN vaccine.

scholarly journals Modelling responses to a smallpox epidemic taking into account uncertainty

2004 ◽  
Vol 132 (1) ◽  
pp. 19-25 ◽  
Author(s):  
J. LEGRAND ◽  
C. VIBOUD ◽  
P. Y. BOELLE ◽  
A. J. VALLERON ◽  
A. FLAHAULT
Keyword(s):  
Reproduction Number ◽  
Large City ◽  
Biological Weapons ◽  
Reference Scenario ◽  
Susceptible Population ◽  
Fourfold Increase ◽  
Epidemic Size ◽  
Ring Vaccination ◽  
Deliberate Release ◽  
Index Cases

Epidemiology and modelling are currently under pressure to build consistent scenarios of control in case of deliberate release of biological weapons. In order to assess the key parameters for the control of a smallpox outbreak in a large city (2 million inhabitants), we built a stochastic model to simulate the course of an epidemic controlled by ring vaccination and case isolation. Assuming a reference scenario with 100 index cases and implementation of intervention 25 days after the attack, the model forecasts an epidemic of 730 cases with an epidemic duration of 240 days. Setting intervention 20 days later would result in an almost fourfold increase in the epidemic size. A multivariate sensitivity analysis has selected three key parameters: the basic reproduction number (i.e. the number of secondary cases infected by one case in an entirely susceptible population, equal to 3 in the reference scenario), time to intervention, and proportion of traced and vaccinated contacts.

scholarly journals Correction: Harnessing Case Isolation and Ring Vaccination to Control Ebola

2015 ◽  
Vol 9 (6) ◽  
pp. e0003888
Author(s):  
Chad Wells ◽  
Dan Yamin ◽  
Martial L. Ndeffo-Mbah ◽  
Natasha Wenzel ◽  
Stephen G. Gaffney ◽  
...  
Keyword(s):  
Ring Vaccination

scholarly journals Ring Vaccination and Smallpox Control

2004 ◽  
Vol 10 (5) ◽  
pp. 832-841 ◽  
Author(s):  
Mirjam Kretzschmar ◽  
Susan van den Hof ◽  
Jacco Wallinga ◽  
Jan van Wijngaarden
Keyword(s):  
Ring Vaccination

scholarly journals CDC releases interim smallpox response plan and guidelines

2001 ◽  
Vol 5 (51) ◽  
Author(s):  
R Harling
Keyword(s):  
United States ◽  
Disease Control ◽  
The United States ◽  
Mass Vaccination ◽  
Ring Vaccination ◽  
Control And Prevention ◽  
Deliberate Release ◽  
Response Plan ◽  
Centers For Disease Control ◽  
Spread Of Infection

The Centers for Disease Control and Prevention (CDC) in the United States (US) last week released its plans to cope with a deliberate release of smallpox (1). The plan centres on rapid ring vaccination of the contacts of infected individuals to contain the spread of infection. Mass vaccination in advance of an outbreak will not be used, partly because the risks associated with vaccination outweigh the risks of exposure to smallpox.

scholarly journals Teschen disease (Teschovirus encephalomyelitis) eradication in Czechoslovakia: a historical report

2009 ◽  
Vol 54 (No. 11) ◽  
pp. 550-560 ◽  
Author(s):  
V. Kouba
Keyword(s):  
Viral Disease ◽  
Eradication Programme ◽  
Disease Mortality ◽  
Ring Vaccination ◽  
North Eastern ◽  
Outbreak Areas ◽  
The Central Nervous System ◽  
Domestic Refuse ◽  
Waste Food ◽  
Production Industry

Teschen disease (previously also known as Klobouk’s disease), actually called <i>Teschovirus encephalomyelitis</i>, is a virulent fatal viral disease of swine, characterized by severe neurological disorders of encephalomyelitis. It was initially discovered in the Teschen district of North-Eastern Moravia. During the 1940s and 1950s it caused serious losses to the pig production industry in Europe. The most critical situation at that time, however, was in the former Czechoslovakia. A nationally organized eradication programme started in 1952. That year the reported number of new cases of Teschen disease reached 137 396, i.e., an incidence rate of 2 794 per 100 000 pigs, in 14 801 villages with 65 597 affected farms, i.e., 4.43 affected farms per village and 2.10 diseased pigs per affected farm. The average territorial density of new cases was 1.07 per km2. For etiological diagnosis histological investigation of the central nervous system, isolation of virus and seroneutralization were used. Preventive measures consisted in feeding pigs with sterilized waste food and in ring vaccination. Eradication measures took the form of the timely detection and reporting of new cases, isolating outbreak areas, and the slaughter of intrafocal pigs followed by sanitation measures. Diseased pigs were usually destroyed in rendering facilities. The carcasses of other intrafocal pigs were treated as conditionally comestible, i.e., only after sterilization. During the years 1952–1965 from a reported 537 480 specifically diseased pigs 36 558 died; i.e., Teschen disease mortality rate was 6.80% while other intrafocal pigs (88.12%) were urgently slaughtered. During the whole eradication programme there were a reported 542 971 Teschen disease cases. The disease was found mainly in small private farms where domestic refuse was used for pig feeding without proper sterilization. During 1959–1972 there were a reported 16 981 529 vaccinations using a vaccine of national origin. The ratio of vaccination to national pig population was reduced from 0.4904 in 1959 to 0.0786 in 1972. During 1959–1965 the ratio of reported vaccinations to reported new diseased pigs was 521 : 1 and during 1960–1965 the ratio of reported vaccinations to reported intrafocal pigs was 85 : 1. After eradication the vaccination was stopped. The last cases were detected in 1973 and from that time Czech and Slovak territories have been free from this dangerous infection.

scholarly journals Erratum to: Impact of Imitation Processes on the Effectiveness of Ring Vaccination

2014 ◽  
Vol 76 (11) ◽  
pp. 2941-2944
Author(s):  
Chad R. Wells ◽  
Jean M. Tchuenche ◽  
Lauren Ancel Meyers ◽  
Alison P. Galvani ◽  
Chris T. Bauch
Keyword(s):  
Ring Vaccination

Measles Ring Vaccination in Dormitories: An Outbreak Containment Measure and Simulation Study

2019 ◽  
Author(s):  
Rachael Pung ◽  
Tau Hong Lee ◽  
Xinyi Peh ◽  
Lin Cui ◽  
Cuiqin poh ◽  
...  
Keyword(s):  
Simulation Study ◽  
Ring Vaccination ◽  
Containment Measure

scholarly journals The Epidemiological Framework for Biological Invasions (EFBI): an interdisciplinary foundation for the assessment of biosecurity threats

NeoBiota ◽  
2020 ◽  
Vol 62 ◽  
pp. 161-192 ◽  
Author(s):  
Philip E. Hulme ◽  
Richard Baker ◽  
Robert Freckleton ◽  
Rosemary S. Hails ◽  
Matt Hartley ◽  
...  
Keyword(s):  
Biological Invasions ◽  
Native Species ◽  
Herd Immunity ◽  
Landscape Scale ◽  
The Novel ◽  
Demographic Models ◽  
Force Of Infection ◽  
Species Invasions ◽  
Ring Vaccination ◽  
Cordon Sanitaire

Emerging microparasite (e.g. viruses, bacteria, protozoa and fungi) epidemics and the introduction of non-native pests and weeds are major biosecurity threats worldwide. The likelihood of these threats is often estimated from probabilities of their entry, establishment, spread and ease of prevention. If ecosystems are considered equivalent to hosts, then compartment disease models should provide a useful framework for understanding the processes that underpin non-native species invasions. To enable greater cross-fertilisation between these two disciplines, the Epidemiological Framework for Biological Invasions (EFBI) is developed that classifies ecosystems in relation to their invasion status: Susceptible, Exposed, Infectious and Resistant. These states are linked by transitions relating to transmission, latency and recovery. This viewpoint differs markedly from the species-centric approaches often applied to non-native species. It allows generalisations from epidemiology, such as the force of infection, the basic reproductive ratio R0, super-spreaders, herd immunity, cordon sanitaire and ring vaccination, to be discussed in the novel context of non-native species and helps identify important gaps in the study of biological invasions. The EFBI approach highlights several limitations inherent in current approaches to the study of biological invasions including: (i) the variance in non-native abundance across ecosystems is rarely reported; (ii) field data rarely (if ever) distinguish source from sink ecosystems; (iii) estimates of the susceptibility of ecosystems to invasion seldom account for differences in exposure to non-native species; and (iv) assessments of ecosystem susceptibility often confuse the processes that underpin patterns of spread within -and between- ecosystems. Using the invasion of lakes as a model, the EFBI approach is shown to present a new biosecurity perspective that takes account of ecosystem status and complements demographic models to deliver clearer insights into the dynamics of biological invasions at the landscape scale. It will help to identify whether management of the susceptibility of ecosystems, of the number of vectors, or of the diversity of pathways (for movement between ecosystems) is the best way of limiting or reversing the population growth of a non-native species. The framework can be adapted to incorporate increasing levels of complexity and realism and to provide insights into how to monitor, map and manage biological invasions more effectively.

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