scholarly journals The epidemiological signature of pathogen populations that vary in the relationship between free-living survival and virulence

2020 ◽  
Author(s):  
Lourdes M. Gomez ◽  
Victor A Meszaros ◽  
Wendy C. Turner ◽  
C. Brandon Ogbunugafor
Keyword(s):  
Public Health ◽  
Disease Dynamics ◽  
Free Living ◽  
Evolutionary Changes ◽  
Evolution Of Virulence ◽  
Parasite Survival ◽  
Transmission Studies ◽  
Pathogen Populations ◽  
Host Parasite ◽  
The Relationship

ABSTRACTThe relationship between parasite virulence and transmission is a pillar of evolutionary theory that has specific implications for public health. Part of this canon involves the idea that virulence and free-living survival (a key component of transmission) may have different relationships in different host-parasite systems. Most examinations of the evolution of virulence-transmission relationships—theoretical or empirical in nature—tend to focus on the evolution of virulence, with transmission a secondary consideration. And even within transmission studies, the focus on free-living survival is a smaller subset, though recent studies have examined its importance in the ecology of infectious diseases. Few studies have examined the epidemic-scale consequences of variation in survival across different virulence-survival relationships. In this study, we utilize a mathematical model motivated by aspects of SARS-CoV-2 natural history to investigate how evolutionary changes in survival may influence several aspects of disease dynamics at the epidemiological scale. Across virulence-survival relationships (where these traits are positively or negatively correlated), we found that small changes (5% above and below the nominal value) in survival can have a meaningful effect on certain outbreak features, including the R0, and the size of the infectious peak in the population. These results highlight the importance of properly understanding the mechanistic relationship between virulence and parasite survival, as evolution of increased survival across different relationships with virulence will have considerably different epidemiological signatures.

scholarly journals The Epidemiological Signature of Pathogen Populations That Vary in the Relationship between Free-Living Parasite Survival and Virulence

Viruses ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 1055 ◽  
Author(s):  
Lourdes M. Gomez ◽  
Victor A. Meszaros ◽  
Wendy C. Turner ◽  
C. Brandon Ogbunugafor
Keyword(s):  
Public Health ◽  
Disease Dynamics ◽  
Free Living ◽  
Evolutionary Changes ◽  
Evolution Of Virulence ◽  
Parasite Survival ◽  
Transmission Studies ◽  
Pathogen Populations ◽  
Host Parasite ◽  
The Relationship

The relationship between parasite virulence and transmission is a pillar of evolutionary theory that has implications for public health. Part of this canon involves the idea that virulence and free-living survival (a key component of transmission) may have different relationships in different host–parasite systems. Most examinations of the evolution of virulence-transmission relationships—Theoretical or empirical in nature—Tend to focus on the evolution of virulence, with transmission being a secondary consideration. Even within transmission studies, the focus on free-living survival is a smaller subset, though recent studies have examined its importance in the ecology of infectious diseases. Few studies have examined the epidemic-scale consequences of variation in survival across different virulence–survival relationships. In this study, we utilize a mathematical model motivated by aspects of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) natural history to investigate how evolutionary changes in survival may influence several aspects of disease dynamics at the epidemiological scale. Across virulence–survival relationships (where these traits are either positively or negatively correlated), we found that small changes (5% above and below the nominal value) in survival can have a meaningful effect on certain outbreak features, including R0, and on the size of the infectious peak in the population. These results highlight the importance of properly understanding the mechanistic relationship between virulence and parasite survival, as the evolution of increased survival across different relationships with virulence may have considerably different epidemiological signatures.

scholarly journals An Analysis of Host Adaptation and Its Relationship with Virulence in Cucumber mosaic virus

2005 ◽  
Vol 95 (7) ◽  
pp. 827-833 ◽  
Author(s):  
Soledad Sacristán ◽  
Aurora Fraile ◽  
José M. Malpica ◽  
Fernando García-Arenal
Keyword(s):  
Cucumber Mosaic Virus ◽  
Mosaic Virus ◽  
Experimental Evolution ◽  
Host Adaptation ◽  
Trade Offs ◽  
Evolution Of Virulence ◽  
Host Growth ◽  
Before And After ◽  
Pathogen Populations ◽  
The Relationship

The host range of a pathogen can have special consequences on its evolution and the evolution of its virulence. For generalists, adaptation to different hosts may be conditioned by different trade-offs in the pathogen's life history and be affected by evolutionary processes that shape pathogen populations. We have examined adaptation of Cucumber mosaic virus (CMV) to different hosts, and analyzed the relationship between host adaptation and virulence. For this, six CMV isolates from central Spain from three different hosts were compared for the ability to multiply and to affect host growth. These analyses were done before and after an experimental evolution process consisting of 10 serial passages in the original host of the isolate. The differential capacity to infect different hosts was compatible with host adaptation. However, the capacity to multiply in different hosts did not provide evidence of host adaptation and was not improved after 10 passages, suggesting that fitness of the natural population of CMV was at, or near to, its maximum. No relationship was found between capacity of multiplication and virulence in any of the three different hosts. These results suggest that the “trade-off” model for the evolution of virulence may not apply to CMV.

scholarly journals The roles of environmental variation and parasite survival in virulence–transmission relationships

2021 ◽  
Vol 8 (6) ◽  
pp. 210088
Author(s):  
Wendy C. Turner ◽  
Pauline L. Kamath ◽  
Henriette van Heerden ◽  
Yen-Hua Huang ◽  
Zoe R. Barandongo ◽  
...  
Keyword(s):  
Life History ◽  
Adaptive Dynamics ◽  
Life History Evolution ◽  
Infectious Agent ◽  
Environmental Context ◽  
Parasite Life Cycle ◽  
Trade Offs ◽  
Evolution Of Virulence ◽  
Parasite Survival ◽  
Host Parasite

Disease outbreaks are a consequence of interactions among the three components of a host–parasite system: the infectious agent, the host and the environment. While virulence and transmission are widely investigated, most studies of parasite life-history trade-offs are conducted with theoretical models or tractable experimental systems where transmission is standardized and the environment controlled. Yet, biotic and abiotic environmental factors can strongly affect disease dynamics, and ultimately, host–parasite coevolution. Here, we review research on how environmental context alters virulence–transmission relationships, focusing on the off-host portion of the parasite life cycle, and how variation in parasite survival affects the evolution of virulence and transmission. We review three inter-related ‘approaches’ that have dominated the study of the evolution of virulence and transmission for different host–parasite systems: (i) evolutionary trade-off theory, (ii) parasite local adaptation and (iii) parasite phylodynamics. These approaches consider the role of the environment in virulence and transmission evolution from different angles, which entail different advantages and potential biases. We suggest improvements to how to investigate virulence–transmission relationships, through conceptual and methodological developments and taking environmental context into consideration. By combining developments in life-history evolution, phylogenetics, adaptive dynamics and comparative genomics, we can improve our understanding of virulence–transmission relationships across a diversity of host–parasite systems that have eluded experimental study of parasite life history.

scholarly journals Biodiversity loss decreases parasite diversity: theory and patterns

2012 ◽  
Vol 367 (1604) ◽  
pp. 2814-2827 ◽  
Author(s):  
Kevin D. Lafferty
Keyword(s):  
Species Richness ◽  
Food Web ◽  
Biodiversity Loss ◽  
Parasite Diversity ◽  
Free Living ◽  
Parasite Richness ◽  
Living Species ◽  
Host Parasite ◽  
Food Web Complexity ◽  
The Relationship

Past models have suggested host–parasite coextinction could lead to linear, or concave down relationships between free-living species richness and parasite richness. I explored several models for the relationship between parasite richness and biodiversity loss. Life cycle complexity, low generality of parasites and sensitivity of hosts reduced the robustness of parasite species to the loss of free-living species diversity. Food-web complexity and the ordering of extinctions altered these relationships in unpredictable ways. Each disassembly of a food web resulted in a unique relationship between parasite richness and the richness of free-living species, because the extinction trajectory of parasites was sensitive to the order of extinctions of free-living species. However, the average of many disassemblies tended to approximate an analytical model. Parasites of specialist hosts and hosts higher on food chains were more likely to go extinct in food-web models. Furthermore, correlated extinctions between hosts and parasites (e.g. if parasites share a host with a specialist predator) led to steeper declines in parasite richness with biodiversity loss. In empirical food webs with random removals of free-living species, the relationship between free-living species richness and parasite richness was, on average, quasi-linear, suggesting biodiversity loss reduces parasite diversity more than previously thought.

Oral health diseases among the older people: a general health perspective

2020 ◽  
Keyword(s):  
Public Health ◽  
Health Care ◽  
Oral Health ◽  
Older People ◽  
Health Professionals ◽  
General Health ◽  
Oral Health Care ◽  
Oral Diseases ◽  
Public Health Professionals ◽  
The Relationship

Background: The relationship between oral health and general health is gaining interest in geriatric research; however, a lack of studies dealing with this issue from a general perspective makes it somewhat inaccessible to non-clinical public health professionals. Purpose: The purpose of this review is to describe the relationship between oral health and general health of the elderly on the basis of literature review, and to give non-clinical medical professionals and public health professionals an overview of this discipline. Methods: This study was based on an in-depth review of the literature pertaining to the relationship between oral health and general health among the older people. The tools commonly used to evaluate dental health and the academic researches of male elderly people were also reviewed. And future research directions were summarized. Results: Dental caries, periodontal disease, edentulism, and xerostomia are common oral diseases among the older people. Dental caries and periodontal diseases are the leading causes of missing teeth and edentulism. Xerostomia, similar to dry mouth, is another common oral health disease in the older people. No clear correlation exists between the subjective feeling of dryness and an objective decrease of saliva. Rather, both conditions can be explained by changes in saliva. The General Oral Health Assessment Index (GOHAI) and the Oral Health Impact Profile (OHIP) are the main assessment tools used to examine oral health and quality of life in the older people. The GOHAI tends to be more sensitive to objective values pertaining to oral function. In addition, oral health studies in male elderly people are population-based cohort or cross-sectional studies, involving masticatory function, oral prevention, frailty problems, cardiovascular disease risk, and cognitive status. Conclusion: It is possible to reduce the incidence of certain oral diseases, even among individuals who take oral health care seriously. Oral health care should be based on the viewpoint of comprehensive treatment, including adequate nutrition, good life and psychology, and correct oral health care methods. In the future, researchers could combine the results of meta-analysis with the clinical experience of doctors to provide a more in-depth and broader discussion on oral health research topics concerning the older people.

The relationship betweenparityand the incident of perinealruptures on women’s physiological maternity

2019 ◽  
Vol 1 (2) ◽  
Author(s):  
Evi Rosita ◽  
Siti Nurnaningrum
Keyword(s):  
Public Health ◽  
Health Center ◽  
P Value ◽  
Chi Square ◽  
Cross Sectional ◽  
Midwifery Care ◽  
Public Health Center ◽  
Record Data ◽  
The Relationship ◽  
Very High

There are about 2.8 million incident of perineal rupture in maternal physiological labor. In 2050,it is estimated that the incidence of perineal rupture can be 6.3 million if it is not accompanied by a good midwifery care. In 2016, in Trawas, there was (89%) perineal rupture in primiparas and (57%) perineal rupture in multiparas. Perineal rupture incidences due to parity were still very high. This study aims to analyze the relationship between parity and the incidence of perineal rupture . It is quantitative studyusing a cross sectional approach, by using analysis of physiological maternity women  medical record data from January to April 2017 of 130 peoplein Trawas Public Health Center, Mojokerto Regency.The dataanalysis used was Chi - Square , indicated by p value = 0,000 with ɑ = 0,05. It means that the value of p <ɑ, so H1 is accepted. It can be concluded that there is a relationship between parity and the incidence of perineal rupture on physiological maternity women in Trawas Public Health Center,Mojokerto Regency. Midwives can apply collaboration with patients and their families to have physical and psychologicalpreparation with an alternative of hypnobirthing methods.

PELAYANAN PUBLIK KESEHATAN PUSKESMAS DALAM MEMBERIKAN KEPUASAN MASYARAKAT DI KABUPATEN SUMENEP

2018 ◽  
Vol 3 (3) ◽  
Author(s):  
Aryo Wibisono ◽  
R. Amilia Destryana
Keyword(s):  
Public Health ◽  
Logistic Regression ◽  
Patient Satisfaction ◽  
Health Center ◽  
Public Service ◽  
Public Health Center ◽  
The Public ◽  
Regression Methods ◽  
Total Satisfaction ◽  
The Relationship

This study aims to determine the index of public satisfaction in public health center services in Sumenep Regency and the relationship between the services to the public satisfaction. The analysis measured the index of public satisfaction and logistic regression methods to determine the effect of the relationship on total satisfaction in the health services of Public Health Center. The results of the study are the alignment between interests and patient satisfaction is still not aligned, there are still differences between interests and satisfaction, the pattern of the result is the relationship between the assurance dimension to the service satisfaction of the public health center, and the results of the index of public satisfaction  values show that the results of the community assess the public health center performance is very good by getting an A grade. Keywords: public service, logistic regretion, index of public satisfaction

scholarly journals Populist radical right parties, welfare policy and population health in Europe

2019 ◽  
Vol 29 (Supplement_4) ◽  
Author(s):  
C Rinaldi ◽  
M P M Bekker
Keyword(s):  
Public Health ◽  
Welfare State ◽  
Population Health ◽  
State Policy ◽  
Political System ◽  
Radical Right ◽  
The Political ◽  
Policy Agenda ◽  
The Public ◽  
The Relationship

Abstract Background The political system is an important influencing factor for population health but is often neglected in the public health literature. This scoping review uses insights from political science to explore the possible public health consequences of the rise of populist radical right (PRR) parties in Europe, with welfare state policy as a proxy. The aim is to generate hypotheses about the relationship between the PRR, political systems and public health. Methods A literature search on PubMed, ScienceDirect and Google Scholar resulted in 110 original research articles addressing 1) the relationship between the political system and welfare state policy/population health outcomes or 2) the relationship between PRR parties and welfare state policy/population health outcomes in Europe. Results The influence of political parties on population health seems to be mediated by welfare state policies. Early symptoms point towards possible negative effects of the PRR on public health, by taking a welfare chauvinist position. Despite limited literature, there are preliminary indications that the effect of PRR parties on health and welfare policy depends on vote-seeking or office-seeking strategies and may be mediated by the political system in which they act. Compromises with coalition partners, electoral institutions and the type of healthcare system can either restrain or exacerbate the effects of the PRR policy agenda. EU laws and regulations can to some extent restrict the nativist policy agenda of PRR parties. Conclusions The relationship between the PRR and welfare state policy seems to be mediated by the political system, meaning that the public health consequences will differ by country. Considering the increased popularity of populist parties in Europe and the possibly harmful consequences for public health, there is a need for further research on the link between the PRR and public health.

scholarly journals 31.B. Workshop: Public health and urban design: an interdisciplinary approach to promote autism friendly environments

2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
◽  
Keyword(s):  
Public Health ◽  
Risk Factors ◽  
Environmental Factors ◽  
Built Environment ◽  
Urban Design ◽  
Significant Role ◽  
Prevalence Rates ◽  
Environmental Characteristics ◽  
The Relationship

Abstract Autism is a set of heterogeneous neurodevelopmental conditions, characterised by early-onset difficulties in social communication and restricted, repetitive behaviour and interests. The worldwide population prevalence is about 1% with an increasing incidence and prevalence rates. Autism affects more male than female individuals, and comorbidity is common (&gt;70% have concurrent conditions). Determinants of these changes in incidence and prevalence rates may also be related to exposure to environmental factors and to modifications in diagnostic concepts and criteria. In spite of the uncertainty in determinants of incidence of autisms, there is evidence that environmental characteristics play a significant role both as autism risk factors and as potential obstacles that influence the capabilities of autonomously and fully “using” everyday spaces. The workshop aims to provide a framework on risk factors of autism and explore the relationship with the built environment, focusing on the quality of the everyday spaces and projecting the effects that it could have in the long term on achieving a desirable level of quality of life. The 11th Sustainable Development Goals of United Nations “Make cities inclusive, safe, resilient and sustainable” underlines the necessity of designing policies and projects acting to enhance and promote healthy cities and communities by addressing the needs of the most vulnerable groups of inhabitants. Herewith we bring together the discipline of Public Health and Urban Design to promote an interdisciplinary debate on a little explored topic investigating how the approaches adopted during childhood to promote the wellbeing of people with ASD can be related or strengthen by focusing also on built environment design intervention to pursue and reach the same objectives even during adulthood. The workshop will consist of four presentations. The first focuses on giving an overview on current knowledge of intervention for people with autism, presenting also criteria for evidence-based interventions. The second explores the relationship between autism and built environment by providing an exhaustive framework of the available research literature in order to identify a first set of spatial requirements for autism friendly cities. The third examines the impact of built environment on ASD users with the aim of developing a specific evaluation tool for healthcare spaces and best practices formulation according to the specific sensorial hypo- or hyper-activation of people with autism. Finally, the fourth reports the results of a two years Research & Development project called “GAP REDUCE” finalized at developing an Assistive Technology tool to support people with ASD, adult and high-functioning, to plan urban itineraries towards daily destinations. Key messages World's incidence of autism is about 1% with an increasing incidence whose determining rates may also be related to environmental factors and to modifications in diagnostic concepts and criteria. Environmental characteristics play a significant role also as potential obstacles that influence the capabilities of people with autism of autonomously and fully “using” everyday spaces.

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