Three studies relating to the vector competency of several species of ticks and <i>Simulium</i> spp. (blackflies) for <i>Ehrlichia risticii</i>, causative agent of Potomac horse fever (PHF) and <i>Amblyomma variegatum</i> for <i>Cowdria ruminantium</i>, causative agent of heartwater, are described. <i>Dermacentor variabilis, Rhipicephalus sanguineus, Amblyomma americanum and Ixodes scapularis</i> ticks were investigated for their ability to acquire and transmit PHF. Larval and nymphal ticks were exposed to <i>E. risticii</i> by feeding on mice inoculated with the organism. Molted exposed ticks were then allowed to feed on susceptible ponies or mice and were examined by light and electron microscopy. No evidence of transmission, either clinically or by seroconversion in mice or ponies was observed. Blackflies (<i>Simulium</i> spp.) were trapped in an area endemic for PHF and inoculated into mice in an attempt to demonstrate <i>I. risticii</i>. No evidence of seroconversion by mice to <i>E. risticii</i> was observed. Two laboratory colonies of <i>Amblyomma variegatum</i> ticks were investigated for their ability to acquire and transmit C. <i>ruminantium</i> and was febrile. Nymphs from both laboratory groups were simultaneously fed on a goat that had been infected with C. <i>ruminantium</i> and was febrile. Engorged nymphs from both groups were replete from feeding on three consecutive days. Nymphs from both groups were then incubated under identical conditions until molting. / Ph. D.

Aedes mosquitoes are responsible for the transmission of several arboviruses throughout tropical and subtropical regions of the world. In the Americas, Aedes aegypti is the most competent vector of dengue, chikungunya, Zika, and yellow fever. With up to 400 million cases globally each year, dengue fever is the fastest growing vector-borne disease in the world, and it has become an increasingly significant risk to global health. In the Western Hemisphere, dengue, and more recently chikungunya and Zika, exists throughout much of Latin America and the Caribbean. Both diseases are spread via Aedes mosquitoes and both constitute major health risks in Costa Rica. A dengue outbreak in Costa Rica in 2013 was the largest epidemic in the country since the return of the disease in 1993. Moreover, between 2014 and 2015 there was a 54.9% increase in dengue cases in Costa Rica, further demonstrating the relevancy of research on mosquito-borne diseases. Given this context, this study employs qualitative methods to critically investigate measures to combat Aedes mosquito-borne diseases in Costa Rica. Data were collected using household interviews (n = 80); semi-structured key informant interviews with public health officials, researchers, nonprofit organizations, and community leaders (n = 22); and a focus group discussion in each of two study areas. The results provide broad and place-specific information about mosquito control efforts and other actions deployed in Costa Rica to mitigate mosquito-borne diseases. The data reveal differences in perceptions and disease incidence among household interviewees as well as where households source information about mosquitoes and mosquito-borne diseases. Varying degrees of knowledge on mosquitoes and mosquito-borne diseases were uncovered across the study sites, as were differing attitudes among the general population regarding mosquito control techniques (e.g., fumigation, education campaigns, and household visits by public health officials). Additionally, data indicated a gap in knowledge regarding the ability of the public to report mosquito-related problems to health authorities. Households also exhibited discrepancies in knowledge pertaining to chikungunya transmission and details about the vector. / Master of Science

Human norovirus (NoV) causes gastroenteritis worldwide and has been associated with a number of produce related outbreaks. The design of effective inactivation and prevention procedures requires an understanding of virus survival in environments applicable to the production and processing of fresh produce. To evaluate the extent of NoV risk from farm to fork, the survival of murine norovirus (MNV), a surrogate for human NoV, was studied on stainless steel disks, soil and in bottled water for 42 days and on lettuce for 15 days in the laboratory. Stability experiments were then conducted on farm during one lettuce planting/harvest cycle, for 4 weeks. MNV stability was tested at room temperature in the laboratory or under ambient conditions on the farm. A one log reduction in virus titre was achieved after 30 days in water, 4 days on lettuce, 15 days on stainless steel disks, 12 days on loamy and sandy soil. For farm testing, infectious virus was recovered from both soil and lettuce on the day of inoculation. Although infectious virus was not recovered at later time points, the viral genomes were detected for up to four weeks. The observed long-term persistence of NoV, under both laboratory and field conditions, provides valuable information for developing risk assessments and control procedures to limit the possibility for NoV transmission in the food supply.

Human norovirus (NoV) causes gastroenteritis worldwide and has been associated with a number of produce related outbreaks. The design of effective inactivation and prevention procedures requires an understanding of virus survival in environments applicable to the production and processing of fresh produce. To evaluate the extent of NoV risk from farm to fork, the survival of murine norovirus (MNV), a surrogate for human NoV, was studied on stainless steel disks, soil and in bottled water for 42 days and on lettuce for 15 days in the laboratory. Stability experiments were then conducted on farm during one lettuce planting/harvest cycle, for 4 weeks. MNV stability was tested at room temperature in the laboratory or under ambient conditions on the farm. A one log reduction in virus titre was achieved after 30 days in water, 4 days on lettuce, 15 days on stainless steel disks, 12 days on loamy and sandy soil. For farm testing, infectious virus was recovered from both soil and lettuce on the day of inoculation. Although infectious virus was not recovered at later time points, the viral genomes were detected for up to four weeks. The observed long-term persistence of NoV, under both laboratory and field conditions, provides valuable information for developing risk assessments and control procedures to limit the possibility for NoV transmission in the food supply.

Human norovirus (NoV) causes gastroenteritis worldwide and has been associated with a number of produce related outbreaks. The design of effective inactivation and prevention procedures requires an understanding of virus survival in environments applicable to the production and processing of fresh produce. To evaluate the extent of NoV risk from farm to fork, the survival of murine norovirus (MNV), a surrogate for human NoV, was studied on stainless steel disks, soil and in bottled water for 42 days and on lettuce for 15 days in the laboratory. Stability experiments were then conducted on farm during one lettuce planting/harvest cycle, for 4 weeks. MNV stability was tested at room temperature in the laboratory or under ambient conditions on the farm. A one log reduction in virus titre was achieved after 30 days in water, 4 days on lettuce, 15 days on stainless steel disks, 12 days on loamy and sandy soil. For farm testing, infectious virus was recovered from both soil and lettuce on the day of inoculation. Although infectious virus was not recovered at later time points, the viral genomes were detected for up to four weeks. The observed long-term persistence of NoV, under both laboratory and field conditions, provides valuable information for developing risk assessments and control procedures to limit the possibility for NoV transmission in the food supply.

Human norovirus (NoV) causes gastroenteritis worldwide and has been associated with a number of produce related outbreaks. The design of effective inactivation and prevention procedures requires an understanding of virus survival in environments applicable to the production and processing of fresh produce. To evaluate the extent of NoV risk from farm to fork, the survival of murine norovirus (MNV), a surrogate for human NoV, was studied on stainless steel disks, soil and in bottled water for 42 days and on lettuce for 15 days in the laboratory. Stability experiments were then conducted on farm during one lettuce planting/harvest cycle, for 4 weeks. MNV stability was tested at room temperature in the laboratory or under ambient conditions on the farm. A one log reduction in virus titre was achieved after 30 days in water, 4 days on lettuce, 15 days on stainless steel disks, 12 days on loamy and sandy soil. For farm testing, infectious virus was recovered from both soil and lettuce on the day of inoculation. Although infectious virus was not recovered at later time points, the viral genomes were detected for up to four weeks. The observed long-term persistence of NoV, under both laboratory and field conditions, provides valuable information for developing risk assessments and control procedures to limit the possibility for NoV transmission in the food supply.

Tick-borne encephalitis is a vector-borne zoonotic disease with more than 12,000 annual clinical reported cases globally (WHO, 2021). Tick-borne encephalitis is caused by the flavivirus and transferred by Ixodes ricinus from roe deer to human and affects the central Nervous system. Climate change also increases tick-borne encephalitis incidences in Sweden and fluctuated considerably from year to year. A quantitative study design with secondary data was conducted to analyze the spatial and temporal pattern of Tick-borne encephalitis in Sweden from 1986-2020. The distribution of Tick-borne encephalitis within age and sex, along with other factors were also analyzed. The results showed that Tick-borne encephalitis with passing each year spread across the country. Male and age group, 50-59, have more incidence of Tick-borne encephalitis. Incidents were associated with climate conditions such as temperature and precipitation, which provided a favorable environment for Ixodes ricinus for its lifecycle activities, host searching, and disease transmission. Roe deer population, other vertebrates abundance, vaccination, population interest, economy, and land change are the critical factors that facilitate the disease incidence or control. People who visit forests for hunting, trekking, leisure, and professional activities without proper immunity and preventive measures are at risk to infect with Tick-borne encephalitis. The theory One health approach showed suitable performance for the control of this vulnerable climate zoonotic disease.

NilsonGroup presenterade uppdraget att undersöka vattenbaserade lim som alternativ till lösningsbaserade lim vid tillverkning av skor, vilket var grunden till det här arbetets ämne och avgränsningar har tagits fram. Vattenbaserade lim är ett alternativ till lösningsbaserade lim som inte är lika hälsofarligt, då lösningsmedelkan orsaka allvarliga hälsoeffekter. Enligt NilsonGroup ligger skobranschen steget efter vad det gäller hållbarhet och i nuläget saknas det en satsning på hållbarutveckling, medan andra branscher är bättre på att leta efter nya möjligheter. Det här arbetet vill lyfta fram på vilka sätt vattenbaserade lim är ett mindre riskfylltalternativ till lösningsbaserade lim och visa att skillnaderna i limfogens egenskaper inte blir så olika. Första delen av resultatet innefattar en definition av lim och limning. Fokus ligger på att reda ut vad som krävs och hur en limfog skapas med ett lim mellan två ytor, för att läsaren ska få en grundlig kunskap om det innan arbetet går in på lim i skor. Det presenteras även vilka egenskaper som är viktiga för en limfog och vilka faktorer det är som vanligtvis vägs in vid val av lim. Andra delen handlar om material, lim och limfogar i skoindustrin. Resultatet visar att det är den övre delen av skon och sulan som är den mest kritiska limfogen att skapa vid tillverkningen av en sko, samt att de mest förekommande lim som används vid skotillverkning är av polymererna polyuretan och polykloropren. De material till den övre delen av skon som främst används av NilsonGroup och generellt hela skoindustrin, är syntetiskt skinn, läder och bomull. Till en skos sula används gummi och polyuretan i störst utsträckning. Resultatet kommer fram till fem olika kombinationer av material och vattenbaserade lim som har bra potential att kunna bilda en hållbar limfog. Resultatet visar även att de egenskaper som vattenbaserade och lösningsbaserade polykloropren- och polyuretanlim ger en limfog är lika, så när det kommer till att välja mellan vattenbaserade lim och lösningsbaserade lim, så är det komponenterna i limmen och riskerna de medför som innefattar den stora skillnaden. I bilaga 1presenteras alla de mest förekommande komponenter som polyuretan- och polykloroprenlim består av, samt vilka hälsoeffekter de kan orsaka vid exponering för ämnet. / NilsonGroup presented the assignment to investigate water-borne adhesives as an alternative to solvent-borne adhesives in shoe production. This represent the purpose of this work and the limitations that have been developed. Water-borne adhesives do not pose as serious health risks as solvent-borne adhesives, mainly because of the solvent that may cause serious health risks. According to NilsonGroup, the shoe industry is a step behind in terms of sustainability and there is no investment in sustainable development. While other industries are stepping forward in terms of sustainability. The purpose of this work is to highlight waterborne adhesives as a less critical alternative to solvent-borne adhesives. And to prove that the characteristics between the two choices are not so different. The first part of this work explains adhesives and adhesive bonding. The part explains the requirements and how an adhesive joint is created from an adhesive between two different surfaces. This is necessary to get the reader to understand the basics about adhesive bonding before the work focus on adhesives in shoes. Important properties related to the adhesive joint and the common factors when choosing adhesives is also a part of this work. Second part of this work deals with material, adhesives and adhesive joints in the shoe industry. The upper part of the shoe and sole bonding process is the most critical joint in the shoe and the most common adhesives in the shoe industry is made of polyurethane and polychloroprene polymers. Some common materials used in the upper part of shoes made by NilsonGroup, and the shoe industry overall, are synthetic leather, leather and cotton. The sole is usually made of rubber or polyurethane. The result presents five different combinations of material and waterborne adhesives that may have the potential to produce a durable joint. The result shows that the properties related to waterborne and solvent-borne adhesives are equivalent. When choosing type of adhesive, the components in the adhesives and the health risk they cause, makes up the big difference. Appendix 1 presents common components in polyurethane and polychloroprene adhesives along with health risks that they may cause when exposed.

Cette thése est une synthèse de la morphologie glaciare de la vallée de l'Arve entre Chamonix et Annemasse. Un schéma paléomorphologique est proposé

In Western Europe the incidence of tick-borne encephalitis (TBE) has increased over the last 30 years, coupled with changes in distribution. Modifications in the TBE enzootic cycle, through a combination of changes in temperature, vertebrate abundance and habitat suitability may have increased the risk of TBE in recent years. In Switzerland, analysis using satellite-derived climate data demonstrated that the environment of areas with TBE since the 1980s and areas that recently became endemic for TBE have become more similar between 2001 and 2009. This was coupled with an increase in April, May and June temperature, which could have affected the tick population and/or human exposure to ticks. Deer and boar abundance also changed in some cantons. In Germany, spatio-temporal modelling demonstrated the importance of temperature, vertebrate abundance and unemployment in the incidence and distribution of TBE between 2001 and 2009. Changes in TBE reporting, April, May and June temperature, vertebrate abundance and pesticide use may have contributed to increases in TBE in 1992 and 2001. Human exposure patterns, however, appear to be as important as the enzootic cycle in shaping the incidence of TBE, not only in determining the overall trend but also in interacting with the weekly, seasonal and yearly patterns of tick hazard to give the observed incidence. In Switzerland, in weeks with warm, sunny weather, human exposure to ticks is promoted and short-term increases in tick bites are seen. Human outdoor activity also shifts the seasonal pattern of tick bites, when compared with tick questing. There was no apparent increase in time spent in outdoor activities between the 1990s and 2000s in Italy, Germany and Austria, but survey data demonstrated that walking and hiking were already popular activities across Europe by the 1990s. The popularity of mushroom and berry foraging as a source of income in Latvia, Lithuania and Poland, coupled with the expense of vaccination, provide an inverse link between economic wellbeing and TBE risk. Correspondingly, in 2009, the economic recession was associated with an increase with TBE in these three countries.