scholarly journals Disaster displacement and zoonotic disease dynamics: The impact of structural and chronic drivers in Sindh, Pakistan

2021 ◽  
Vol 1 (12) ◽  
pp. e0000068
Author(s):  
Dorien H. Braam ◽  
Rafiq Chandio ◽  
Freya L. Jephcott ◽  
Alex Tasker ◽  
James L. N. Wood
Keyword(s):  
Rural Communities ◽  
Disease Transmission ◽  
Disease Risk ◽  
Animal Health ◽  
Forced Migration ◽  
Zoonotic Disease ◽  
Transmission Risk ◽  
Disease Dynamics ◽  
Displaced Populations ◽  
The Impact

Projected increases in human and animal displacement driven by climate change, disasters and related environmental degradation will have significant implications to global health. Pathways for infectious disease transmission including zoonoses, diseases transmitted between animals and humans, are complex and non-linear. While forced migration is considered an important driver for the spread of zoonoses, actual disease dynamics remain under researched. This paper presents the findings of a case study investigating how disaster displacement affected zoonotic disease transmission risk following the 2010 ‘superfloods’ in Sindh province, Pakistan. We interviewed 30 key informants and 17 household members across 6 rural communities between March and November 2019, supported by observational studies and a review of secondary data. Results were analysed using the ecosocial theoretical framework. Buffalo, cattle and goats were often the only moveable asset, therefore livestock was an important consideration in determining displacement modality and destination location, and crowded locations were avoided to protect human and animal health. Meanwhile however, livestock was rarely included in the humanitarian response, resulting in communities and households fragmenting according to the availability of livestock provisions. We found that rather than a driver for disease, displacement acted as a process affecting community, household and individual zoonotic disease risk dynamics, based on available resources and social networks before, during and after displacement, rooted in the historical, political and socio-economic context. We conclude that in rural Sindh, disaster displaced populations’ risk of zoonoses is the result of changes in dynamics rooted in pre-existing structural and chronic inequalities, making people more or less vulnerable to disease through multiple interlinked pathways. Our findings have implications for policy makers and humanitarian responders assisting displaced populations dependent on livestock, with a call to integrate livestock support in humanitarian policies and responses for health, survival and recovery.

scholarly journals 205Zoonotic disease transmission risk in displaced populations

2021 ◽  
Vol 50 (Supplement_1) ◽  
Author(s):  
Gates Scholar Dorien Braam ◽  
Freya Jephcott ◽  
James Wood
Keyword(s):  
Risk Factors ◽  
Disease Transmission ◽  
Disease Risk ◽  
Forced Migration ◽  
Zoonotic Disease ◽  
Humanitarian Assistance ◽  
Transmission Risk ◽  
Case Study Methodology ◽  
Displaced Populations ◽  
Zoonotic Disease Transmission

Abstract Background Repeated spillover events of zoonotic diseases from animals to humans, in combination with unprecedented levels of forced migration, present a major challenge to the global health security agenda. Infectious disease risk is affected by a range of ecological, political and socio-economic drivers. Methods This study uses a qualitative case study methodology to determine how displacement affects the risks of zoonotic disease transmission. Based on key informant interviews and observational studies in Jordan and Pakistan, the study analyses social-structural factors impacting zoonotic disease transmission. Results The study shows that displacement may influence zoonotic disease transmission through its impact on environmental, socio-economic and behavioural factors, influenced by historical, political and socio-economic processes. Sporadic outbreaks of zoonoses including cutaneous leishmaniasis, rabies and Tuberculosis are reported among displaced populations. Risk factors include a decline in health services, increased population density, changes in environment, and reduced quality and availability of shelter, water and nutrition, in turn determining vulnerability to vectors and pathogens. Conclusions Risk factors affecting zoonoses in displacement are complex and interlinked. While the presence of animals may increase the risk in densely populated areas lacking hygiene, livestock may be beneficial to the health status of displaced by improving nutrition. Responses need to be interdisciplinary, multilevel and contextualized. Key messages To mitigate the risk of zoonotic disease transmission during displacement, responses need to include pathogen and vector control, as well as reducing vulnerability to disease, including through access to health and veterinary services and humanitarian assistance.

scholarly journals The impact of active case finding among high-risk populations on the decline of tuberculosis incidence

2021 ◽  
Author(s):  
Aleksandra Tomczak ◽  
Dominika Warmjak ◽  
Aneta Wiśniewska
Keyword(s):  
High Risk ◽  
Disease Transmission ◽  
Reproduction Number ◽  
Case Finding ◽  
Transmission Risk ◽  
Active Case Finding ◽  
Disease Dynamics ◽  
Active Screening ◽  
Active Case ◽  
The Impact

Introduction: Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis. In 2019 the WHO reported approximately 10 million TB cases and 1.4 million deaths worldwide. TB still remains one of the leading causes of death in humans. Brazil is one of 30 countries with the highest TB burden with 96,000 new cases and 6,700 deaths reported in 2019. From 2015 the TB incidence is increasing by 2%–3% annually. It means that TB control programs need to be improved. Aim: Our aim is to show the impact of active case finding of TB cases among a high-risk subpopulation on decline of the incidence in the general population. Material and methods: We use a SIS-type compartmental mathematical model to describe the disease dynamics. We consider the population as a heterogeneous population which differ in disease transmission risk. Using best-fit techniques we compare the actual data with the model. For the fitted parameters we calculate the basic reproduction number and estimate the TB trends for the next few years applying several preventative protocols. Results and discussion: Using numerical simulations we examine the impact of ACF on the disease dynamics. We show that active screening among high risk subpopulations can help to reduce TB spread. We show how the reproduction number and estimated incidence decline depend on the detection rate. Conclusions: Active screening is one of the most effective ways for reducing the spread of disease. However, due to financial constraints, it can only be used to a limited extent. Properly applied detection can limit the spread of the disease while minimizing costs.

scholarly journals Feeding sites promoting wildlife-related tourism might highly expose the endangered Yunnan snub-nosed monkey (Rhinopithecus bieti) to parasite transmission

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Eve Afonso ◽  
Rong Fu ◽  
Amaël Dupaix ◽  
Anne-Claude Goydadin ◽  
ZhongHua Yu ◽  
...  
Keyword(s):  
Disease Transmission ◽  
High Throughput Sequencing ◽  
Animal Health ◽  
Buffer Zone ◽  
Transmission Risk ◽  
Parasite Transmission ◽  
Rhinopithecus Bieti ◽  
Domesticated Animals ◽  
Feeding Sites ◽  
In The Wild

AbstractAn increasing number of studies have found that the implementation of feeding sites for wildlife-related tourism can affect animal health, behaviour and reproduction. Feeding sites can favour high densities, home range overlap, greater sedentary behaviour and increased interspecific contacts, all of which might promote parasite transmission. In the Yunnan snub-nosed monkey (Rhinopithecus bieti), human interventions via provisioning monkeys at specific feeding sites have led to the sub-structuring of a group into genetically differentiated sub-groups. The fed subgroup is located near human hamlets and interacts with domesticated animals. Using high-throughput sequencing, we investigated Entamoeba species diversity in a local host assemblage strongly influenced by provisioning for wildlife-related tourism. We identified 13 Entamoeba species or lineages in faeces of Yunnan snub-nosed monkeys, humans and domesticated animals (including pigs, cattle, and domestic chicken). In Yunnan snub-nosed monkeys, Entamoeba prevalence and OTU richness were higher in the fed than in the wild subgroup. Entamoeba polecki was found in monkeys, pigs and humans, suggesting that this parasite might circulates between the wild and domestic components of this local social–ecological system. The highest proportion of faeces positive for Entamoeba in monkeys geographically coincided with the presence of livestock and humans. These elements suggest that feeding sites might indirectly play a role on parasite transmission in the Yunnan snub-nosed monkey. The implementation of such sites should carefully consider the risk of creating hotspots of disease transmission, which should be prevented by maintaining a buffer zone between monkeys and livestock/humans. Regular screenings for pathogens in fed subgroup are necessary to monitor transmission risk in order to balance the economic development of human communities dependent on wildlife-related tourism, and the conservation of the endangered Yunnan snub-nosed monkey.

scholarly journals Mobilising community-based research on zoonotic infections: A case study of longitudinal cohorts in Vietnam

2015 ◽  
Vol 8 (1) ◽  
pp. 23-42 ◽  
Author(s):  
Karen Saylors ◽  
Tue Ngo Tri ◽  
Toan Tran Khanh ◽  
Kiet Bach Tuan ◽  
Heiman FL Wertheim ◽  
...  
Keyword(s):  
Rural Communities ◽  
Participatory Research ◽  
Disease Transmission ◽  
Disease Surveillance ◽  
Animal Health ◽  
Community Based Research ◽  
Zoonotic Infections ◽  
Response Capacity ◽  
Domestic Livestock ◽  
Study Sites

We initiated the Vietnam Initiative on Zoonotic Infections (VIZIONS) research program to better understand the epidemiology of disease transmission at the human–animal interface in Vietnamese rural communities and to integrate One Health approaches to disease surveillance. We established a longitudinal community cohort study of individuals with occupational exposure to animals, which involves concurrent targeted sampling from domestic livestock species and follow-up monitoring of human clinical cases. The project was implemented by government agencies at the provincial and district levels of the public health and animal health sectors in Vietnam. Engaging with rural communities builds response capacity at the grassroots level, and has improved dialogue between local stakeholders responsible for monitoring human and animal health. Here we describe the process of initiating participatory research and cohort field implementation over the first year in two study sites in Vietnam.Keywords: Vietnam, participatory research, zoonoses, field epidemiology

scholarly journals Global shifts in mammalian population trends reveal key predictors of virus spillover risk

2020 ◽  
Vol 287 (1924) ◽  
pp. 20192736 ◽  
Author(s):  
Christine K. Johnson ◽  
Peta L. Hitchens ◽  
Pranav S. Pandit ◽  
Julie Rushmore ◽  
Tierra Smiley Evans ◽  
...  
Keyword(s):  
Disease Transmission ◽  
Close Contact ◽  
Anthropogenic Activities ◽  
Mammalian Species ◽  
Species Abundance ◽  
Zoonotic Disease ◽  
Wildlife Habitat ◽  
Transmission Risk ◽  
Population Declines ◽  
Zoonotic Viruses

Emerging infectious diseases in humans are frequently caused by pathogens originating from animal hosts, and zoonotic disease outbreaks present a major challenge to global health. To investigate drivers of virus spillover, we evaluated the number of viruses mammalian species have shared with humans. We discovered that the number of zoonotic viruses detected in mammalian species scales positively with global species abundance, suggesting that virus transmission risk has been highest from animal species that have increased in abundance and even expanded their range by adapting to human-dominated landscapes. Domesticated species, primates and bats were identified as having more zoonotic viruses than other species. Among threatened wildlife species, those with population reductions owing to exploitation and loss of habitat shared more viruses with humans. Exploitation of wildlife through hunting and trade facilitates close contact between wildlife and humans, and our findings provide further evidence that exploitation, as well as anthropogenic activities that have caused losses in wildlife habitat quality, have increased opportunities for animal–human interactions and facilitated zoonotic disease transmission. Our study provides new evidence for assessing spillover risk from mammalian species and highlights convergent processes whereby the causes of wildlife population declines have facilitated the transmission of animal viruses to humans.

scholarly journals The impact of news exposure on collective attention in the United States during the 2016 Zika epidemic

2018 ◽  
Author(s):  
Michele Tizzoni ◽  
André Panisson ◽  
Daniela Paolotti ◽  
Ciro Cattuto
Keyword(s):  
United States ◽  
Disease Transmission ◽  
Information Seeking ◽  
Media Coverage ◽  
Public Awareness ◽  
News Coverage ◽  
The United States ◽  
Human Behaviour ◽  
Disease Dynamics ◽  
The Impact

AbstractIn recent years, many studies have drawn attention to the important role of collective awareness and human behaviour during epidemic outbreaks. A number of modelling efforts have investigated the interaction between the disease transmission dynamics and human behaviour change mediated by news coverage and by information spreading in the population. Yet, given the scarcity of data on public awareness during an epidemic, few studies have relied on empirical data. Here, we use fine-grained, geo-referenced data from three online sources – Wikipedia, the GDELT Project and the Internet Archive – to quantify population-scale information seeking about the 2016 Zika virus epidemic in the U.S., explicitly linking such behavioural signal to epidemiological data. Geolocalized Wikipedia pageview data reveal that visiting patterns of Zika-related pages in Wikipedia were highly synchronized across the United States and largely explained by exposure to national television broadcast. Contrary to the assumption of some theoretical models, news volume and Wikipedia visiting patterns were not significantly correlated with the magnitude or the extent of the epidemic. Attention to Zika, in terms of Zika-related Wikipedia pageviews, was high at the beginning of the outbreak, when public health agencies raised an international alert and triggered media coverage, but subsequently exhibited an activity profile that suggests nonlinear dependencies and memory effects in the relation between information seeking, media pressure, and disease dynamics. This calls for a new and more general modelling framework to describe the interaction between media exposure, public awareness and disease dynamics during epidemic outbreaks.

scholarly journals Rats in the city: implications for zoonotic disease risk in an urbanizing world

2021 ◽  
Author(s):  
Kim Rebecca Blasdell ◽  
Serge Morand ◽  
Susan G W Laurance ◽  
Stephen L Doggett ◽  
Amy Hahs ◽  
...  
Keyword(s):  
Disease Risk ◽  
Rattus Rattus ◽  
Zoonotic Disease ◽  
Microbial Pathogens ◽  
Abundance And Diversity ◽  
Impact Of Urbanization ◽  
Rodent Community ◽  
And Function ◽  
The Impact ◽  
Reservoir Hosts

Urbanization is rapidly transforming much of Southeast Asia, altering the structure and function of the landscape, as well as the frequency and intensity of the interactions between people, animals, and the environment. In this study, we began to explore the impact of urbanization on zoonotic disease risk by simultaneously characterizing changes in the abundance and diversity of reservoir hosts (rodents), ectoparasite vectors (ticks), and microbial pathogens across a gradient of urbanization in Malaysian Borneo. We found that although rodent species diversity decreased with increasing urbanization, two species appeared to thrive in anthropogenic environments: the invasive urban exploiter, Rattus rattus and the native urban adapter, Sundamys muelleri. R. rattus was strongly associated with the presence of built infrastructure across the gradient and dominated the urban rodent community where it was associated with high microbial diversity and multi-host zoonoses capable of environmental transmission, including Leptospira spp., and Toxoplasma gondii. In contrast, S. muelleri was restricted to sites with a significant vegetative component where it was found at high densities in the urban location. This species was strongly associated with the presence of ticks, including the medically important genera Ambylomma, Haemaphysalis, and Ixodes. Overall, our results demonstrate that the response to urbanization varies by species at all levels: host, ectoparasite, and microbe. This may lead to increased zoonotic disease risk in a subset of environments across urban and urbanizing landscapes that can be reduced through improved pest management and public health messaging.

scholarly journals Towards risk-based surveillance of African Swine Fever in Switzerland

2021 ◽  
Author(s):  
Maria Elena Vargas-Amado ◽  
Luís Pedro Carmo ◽  
John Berezowski ◽  
Claude Fischer ◽  
Maria João Santos ◽  
...  
Keyword(s):  
High Risk ◽  
Wild Boar ◽  
Disease Transmission ◽  
Forest Cover ◽  
Disease Risk ◽  
Animal Health ◽  
African Swine Fever ◽  
Early Disease ◽  
Domestic Pig ◽  
Domestic Pigs

African Swine Fever (ASF) has emerged as a disease of great concern to swine producers and government disease control agencies because of its severe consequences to animal health and the pig industry. Early detection of an ASF introduction is considered essential for reducing the harm caused by the disease. Risk-based surveillance approaches have been used as enhancements to early disease epidemic detection systems in livestock populations. Such approaches may consider the role wildlife plays in hosting and transmitting a disease. In this study, a novel method is presented to estimate and map the risk of introducing ASF into the domestic pig population through wild boar intermediate hosts. It makes use of data about hunted wild boar, rest areas along motorways connecting ASF affected countries to Switzerland, outdoor piggeries, and forest cover. These data were used to compute relative wild boar abundance as well as to estimate the risk of both disease introduction into the wild boar population and disease transmission to domestic pigs. The way relative wild boar abundance was calculated adds to the current state of the art by considering the effect of beech mast on hunting success and the probability of wild boar occurrence when distributing relative abundance values among individual grid cells. The risk of ASF introduction into the domestic pig population by wild boar was highest near the borders of France, Germany, and Italy. On the north side of the Alps, areas of high risk were located on the unshielded side of the main motorway crossing the Central Plateau, which acts as a barrier for wild boar. The results of this study can be used to focus surveillance efforts for early disease detection on high risk areas. The developed method may also inform policies to control other diseases that are transmitted by direct contact from wild boar to domestic pigs.

scholarly journals 187 ANALYZING DISEASE TRANSMISSION RISKS FROM ABATTOIR-DERIVED IN VITRO-PRODUCED BOVINE EMBRYOS

2005 ◽  
Vol 17 (2) ◽  
pp. 244 ◽  
Author(s):  
G. Perry
Keyword(s):  
Disease Transmission ◽  
Disease Risk ◽  
Probability Distributions ◽  
Animal Health ◽  
Calf Serum ◽  
Bovine Embryos ◽  
Culture Cells ◽  
Sources Of Infection ◽  
Level Of Risk

While thousands of in vitro-produced (IVP) bovine embryos have been transferred commercially with no reports of disease transmission, such risks must be considered. Due to differences in their zonae pellucidae, the disease risks with IVP embryos are known to be higher than with in vivo-derived embryos. Possible sources of infection include the oocytes, spermatozoa, serum, and co-culture cells. The Terrestrial Animal Health Code of the Office International des Epizooties (OIE, 2003) stipulates that disease risk management should meet standards set by the World Trade Organization. These standards include subjecting the IVP procedures to quantitative risk assessment to evaluate disease transmission risk. The purpose of the present work was to measure the risks of transmitting disease with IVP embryos obtained from abattoir-derived tissues. A simulation model was developed using Microsoft Excel spreadsheets with the Palisade @RISK (London, UK) software program. The model incorporates probability distributions, the shapes of which reflect the random nature of some of the data (e.g. fluid volumes in cultures and washes) and the conjectural nature of some of the scientific information (e.g. on disease agents). The model is adaptable so that, when accurate data or information become available, variability estimates and degrees of uncertainty can be replaced with fixed values. The model assumes: (1) the IVP method is as described in the IETS Manual (1998); (2) there are five possible sources of infection; donor cow, donor bull, fetal calf serum, bovine serum albumin, and co-culture cells; (3) the disease agents can survive and/or proliferate during in vitro maturation, fertilization and culture; (4) fluid volumes in cultures and washes follow “known” normal distributions; (5) uncertainties in current knowledge of IVP embryos and disease agents can be taken into account by use of appropriate probability distributions; (6) different methods of in vitro fertilization do not affect the level of risk; and (7) different methods of in vitro culture can affect the level of risk. The model as constructed fits comfortably into a single workbook with one worksheet allocated for the model itself and another serving to store data on diseases of interest. Data on oocytes, blastocyst numbers, etc., and on media and wash fluid volumes are held within the model while information relating to particular diseases can be selected from a drop-down list at the top of the first worksheet. The relevant data stored in the database are then retrieved and used for modelling, using Monte Carlo simulation. The model estimates the final titer of the disease agent in IVP embryos and the probability of at least one infective transmission to a recipient, expressed as distributions.

scholarly journals Estimation of Rift Valley fever virus spillover to humans during the Mayotte 2018-2019 epidemic

2020 ◽  
Author(s):  
Raphaëlle Métras ◽  
W John Edmunds ◽  
Chouanibou Youssouffi ◽  
Laure Dommergues ◽  
Guillaume Fournié ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Rift Valley ◽  
Rift Valley Fever ◽  
Disease Risk ◽  
Rift Valley Fever Virus ◽  
Animal Health ◽  
Control Measures ◽  
Real World Data ◽  
Valley Fever ◽  
The Impact

AbstractRift Valley fever (RVF) is an emerging, zoonotic, arboviral haemorrhagic fever threatening livestock and humans mainly in Africa. RVF is of global concern, having expanded its geographical range over the last decades. The impact of control measures on epidemic dynamics using empirical data has not been assessed. Here, we combined seroprevalence livestock and human RVF case data from the 2018-2019 epidemic in Mayotte, with a dynamic mathematical model. Using a Bayesian inference framework, we estimated viral transmission potential amongst livestock, and spillover from livestock to humans, through both direct contact and vector-mediated routes. Model simulations were used to assess the impact of vaccination on reducing the human epidemic size. Reactive vaccination immunising 20% of the livestock population reduced the number of human cases by 30%. To achieve a similar impact, delaying the vaccination by one month required using 50% more vaccine doses, and vaccinating only humans required 20 times as more as the number of doses for livestock. Finally, with 53.92% (95%CrI [44.76-61.29]) of livestock estimated to be immune at the end of the epidemic wave, viral re-emergence in the next rainy season (2019-2020) was unlikely. We present the first mathematical model for RVF fitted to real-world data to estimate virus transmission parameters, and able to inform potential control programmes. Human and animal health surveillance, and timely livestock vaccination appear to be key in reducing disease risk in humans. We furthermore demonstrate the value of a One Health quantitative approach to surveillance and control of zoonotic infectious diseases.

Sign in / Sign up

Export Citation Format

Share Document