Spring Outbreaks Research Articles

Geoparticipation as a tool for mapping calamities mosquito hotspots: A case study from Litovelské Pomoraví, Czechia

The coexistence of humans and nature has been a recurring theme throughout history, gaining particular importance in the context of climate change and the sustainability of our planet for future generations. However, the delicate balance between humans and nature is often disrupted, as exemplified by the Litovelské Pomoraví Protected Landscape Area in Czechia, where close interaction between humans and mosquitoes is a persistent issue. In this area, when environmental conditions are favorable for mosquito outbreaks, the local population living near the floodplain forests experiences significant discomfort for extended periods. The risk of mosquito overpopulation has intensified in recent years, largely attributed to climate change. Rising water temperatures in breeding habitats accelerate the developmental cycles of certain mosquito species, shortening the time required for maturation. This study aims to utilize modern geoinformation techniques to assess mosquito activity within the Litovelské Pomoraví region and evaluate the perceived impact on human populations. The methodological approach integrates the development of a representative population distribution layer and participatory mapping. These efforts culminate in the identification of active mosquito zones and the quantification of the at-risk population. While long-term data indicate that the situation is not deteriorating significantly, the study confirms that elevated mosquito activity continues to disrupt the daily lives of residents and visitors. Notably, summer mosquito outbreaks exert a broader impact than spring outbreaks, affecting both a larger geographic area and a greater proportion of the population.The study’s primary output, the spatial delineation of active mosquito zones and the identification of continuously populated areas at risk, holds significant value for the integrated management of the region. These findings can help mitigate the annual occurrence of mosquito outbreaks, improve the health of the floodplain forest ecosystem, and promote biodiversity conservation.

TROPOMI unravels transboundary transport pathways of atmospheric carbon monoxide in Tibetan Plateau

Numerous studies have reported in situ monitoring and source analysis in the Tibetan Plateau (TP), a region crucial for climate systems. However, a gap remains in understanding the comprehensive distribution of atmospheric pollutants in the TP and their transboundary pollution transport. Here, we analyzed the high-resolution satellite TROPOMI observations from 2018 to 2023 in Tibet and its surrounding areas. Our result reveals that, contrary to the results from in situ surface CO monitoring, Tibet exhibits a distinct seasonality in atmospheric carbon monoxide total column average mixing ratio (XCO), with higher levels in summer and lower levels in winter. This distinctive seasonal pattern may be related to the TP's ‘air pump’ effect and the Asia summer monsoon. Before 2022, the annual growth rate of XCO in Tibet was 1.63 %·year−1; however, it declined by 6.88 % in 2022. Source analysis and satellite observations suggest that CO from South Asia may enter Tibet either by crossing the Himalayas or through the Yarlung Zangbo Grand Canyon. We discovered that spring outbreaks of open biomass burning (OBB) in South and Southeast Asia led to an 11.57–27.98 % increase in XCO over Tibet. Favorable wind pattern and unique topography of the canyon promote the high concentrations CO transport to Tibet. Our greater concern is whether the TP will experience more severe transboundary pollution in the future.

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One of the current issues of small poultry farms is the prevalence of Eimeriosis infection (especially in floor housing conditions). The research activities were conducted throughout 2021-2022 years in the small rural poultry farms of some communities at the RA Armavir and Ararat marzes. Eimeria infection of chickens was identified on the basis of the results of laboratory tests performed throughout the year. Two species of Eimeria were detected: Eimeria acervulina and Eimeria tenella. Infected samples made up 36% of the overall examined ones. Heat and humidity are among the factors of external environment contributing to the Eimeria propagation. During the year, one or two outbreaks of epidemic nature of invasion may be recorded. The intensity of invasion in Armavir and Ararat marzes was 33 % and 39 %, respectively. Weather conditions favor the preservation and sporulation of Eimeria oocysts in the outdoor environment, leading to spring outbreaks of infection. During the research, as a result of the monitoring carried out in the permanently insecure areas against the disease, high indicators of the extensity and intensity of the invasion were recorded from the beginning of April until the first ten days of June. Lack of precipitation in the summer contributed to a sharp decline in the extensity and intensity of the invasion. And in the long and warm autumn, due to heat and humidity, a certain increase in the mentioned indices was registered, which, anyhow, did not lead to autumn outbreaks of the invasion.

Stress, anxiety, depression and burnout in frontline healthcare workers during two peaks of COVID-19 pandemic in Russia

PurposeIn this study we aimed to assess the range of psychopathological symptoms (anxiety, stress, depression, burnout) and risk factors in frontline HCWs during spring and autumn outbreaks of the new coronavirus infection in Russian Federation. MethodsWe conducted two independent, cross-sectional hospital-based online surveys. Data of 2195 HCWs were collected between May 19th and May 26th 2020 and between October 10th and October 17th 2020. Stress, anxiety, depression, burnout and perceived stress were assessed using the Russian versions of SAVE-9 and GAD-7, PHQ-9, MBI and PSS-10 scales. Logistic regression analysis was performed to determine the influence of different variables. ResultsThe study revealed the rates of anxiety, stress, depression, emotional exhaustion and depersonalization and perceived stress as 32.3%, 31.1%, 45.5%, 74.2%, 37.7%,67.8%, respectively. Moreover, 2.4% of HCWs reported suicidal thoughts. The rate of anxiety was higher in October 2020 compared with May 2020. Revealed risk factors included: female gender, younger age, being a physician, working for over a week, living outside of Moscow or Saint Petersburg, being vaccinated against COVID-19. ConclusionThese results demonstrate the need for urgent supportive programs for HCWs fighting COVID-19 that fall into higher risk factors groups and its increasing importance over time.

Spatial relative risk and factors associated with porcine reproductive and respiratory syndrome outbreaks in United States breeding herds

Details of incident cases of porcine reproductive and respiratory syndrome (PRRS) in United States breeding herds were obtained from the Morrison’s Swine Health Monitoring Project. Herds were classified as cases if they reported an outbreak in a given season of the year and non-cases if they reported it in a season other than the case season or if they did not report a PRRS outbreak in any season. The geographic distribution of cases and non-cases was compared in each season of the year. The density of farms that had a PRRS outbreak during summer was higher in Southern Minnesota and Northwest-central Iowa compared to the density of the underlying population of non-case farms. This does not mean that PRRS outbreaks are more frequent during summer in absolute terms, but that there was a geographical clustering of herds breaking during summer in this area. Similar findings were observed in autumn. In addition, the density of farms reporting spring outbreaks was higher in the Southeast of the United States compared to that of the underlying population of non-case farms. A similar geographical clustering of PRRS outbreaks was observed during winter in the Southeast of the United States. Multivariable analyses, adjusting for the effect of known confounders, showed that the incidence rate of PRRS was significantly lower during winter and autumn during the porcine epidemic diarrhea (PED) epidemic years (2013−2014), compared to PRRS incidence rates observed during the winter and autumn of PED pre-epidemic years (2009−2012). After 2014, an increase in the incidence rate of PRRS was observed during winter and spring but not during autumn or summer. Pig dense areas were associated with a higher incidence rate throughout the year. However, this association tended to be stronger during the summer. Additionally, herds with ≥2500 sows had an increased incidence rate during all seasons except spring compared to those with <2500 sows. PRRS incidence was lower in year-round air-filtered herds compared to non-filtered herds throughout the year. We showed that not only the spatial risk of PRRS varies regionally according to the season of the year, but also that the effect of swine density, herd size and air filtering on PRRS incidence may also vary according to the season of the year. Further studies should investigate regional and seasonal drivers of disease. Breeding herds should maintain high biosecurity standards throughout the year.

Future climate change likely to reduce the Australian plague locust (Chortoicetes terminifera) seasonal outbreaks

Climate is a major limiting factor for insect distributions and it is expected that a changing climate will likely alter spatial patterns of pest outbreaks. The Australian plague locust (APL) Chortoicetes terminifera, is the most economically important locust species in Australia. Invasions cause large scale economic damage to agricultural crops and pastures. Understanding the regional-scale and long-term dynamics is a prerequisite to develop effective control and preventive management strategies. In this study, we used a 32-year locust survey database to uncover the relationship between historical bioclimatic variables and spatial seasonal outbreaks by developing two machine learning species distribution models (SDMs), random forest and boosted regression trees. The explanatory variables were ranked by contribution to the generated models. The bio-climate models were then projected into a future climate change scenario (RCP8.5) using downscaled 34 global climate models (GCMs) to assess how climate change may alter APL seasonal distribution patterns in eastern Australia. Our results show that the model for the distribution of spring outbreaks performed better than those for summer and autumn, based on statistical evaluation criteria. The spatial models of seasonal outbreaks indicate that the areas subject to APL outbreaks were likely to decrease in all seasons. Multi-GCM ensemble means show the largest decrease in area was for spring outbreaks, reduced by 93–94% by 2071–2090, while the area of summer outbreaks decreased by 78–90%, and 67–74% for autumn outbreaks. The bioclimatic variables could explain 78–98% outbreak areas change. This study represents an important step toward the assessment of the effects of the changing climate on locust outbreaks and can help inform future priorities for regional mitigation efforts in the context of global climate change in eastern Australia.

Investigation into the Airborne Dissemination of H5N2 Highly Pathogenic Avian Influenza Virus During the 2015 Spring Outbreaks in the Midwestern United States.

We investigated the plausibility of aerosol transmission of H5N2 highly pathogenic avian influenza (HPAI) virus during the 2015 spring outbreaks that occurred in the U.S. midwest. Air samples were collected inside and outside of infected turkey and layer facilities. Samples were tested to assess HPAI virus concentration (RNA copies/m(3) of air), virus viability, and virus distribution by particle size. HPAI virus RNA was detected inside and up to 1000 m from infected facilities. HPAI virus was isolated from air samples collected inside, immediately outside, up to 70 m from infected facilities, and in aerosol particles larger than 2.1 μm. Direct exposure to exhausted aerosols proved to be a significant source of environmental contamination. These findings demonstrate HPAI virus aerosolization from infected flocks, and that both the transport of infectious aerosolized particles and the deposition of particles on surfaces around infected premises represent a potential risk for the spread of HPAI.

Population Vulnerability to Biannual Cholera Outbreaks and Associated Macro-Scale Drivers in the Bengal Delta

The highly populated floodplains of the Bengal Delta have a long history of endemic and epidemic cholera outbreaks, both coastal and inland. Previous studies have not addressed the spatio-temporal dynamics of population vulnerability related to the influence of underlying large-scale processes. We analyzed spatial and temporal variability of cholera incidence across six surveillance sites in the Bengal Delta and their association with regional hydroclimatic and environmental drivers. More specifically, we use salinity and flood inundation modeling across the vulnerable districts of Bangladesh to test earlier proposed hypotheses on the role of these environmental variables. Our results show strong influence of seasonal and interannual variability in estuarine salinity on spring outbreaks and inland flooding on fall outbreaks. A large segment of the population in the Bengal Delta floodplains remain vulnerable to these biannual cholera transmission mechanisms that provide ecologic and environmental conditions for outbreaks over large geographic regions.

Understanding Influenza Backward

Understanding Influenza Backward

A model to predict outbreak periods of the pest blackfly Simulium chutteri Lewis (simuliidae, Diptera) in the Great Fish River, Eastern Cape province, South Africa

AbstractElevated, more constant flows characterize the current flow regime of the Great Fish River (Eastern Cape province, South Africa) following the completion of an interbasin transfer scheme (IBT) in 1977, where prior to this the winter months were often characterized by zero flows. Changes in aquatic macroinvertebrate communities, and in particular outbreaks of the pest blackfly Simulium chutteri Lewis (Diptera: Simuliidae) have been documented in response to these altered flows. Integrated control measures of pest blackfly have been advocated based on flow reductions during the winter months. In this study, a site‐specific discharge threshold of 2 m3 s−1 was identified as a flow reduction target based on the amount of hydraulic habitat available to S. chutteri larvae within a particular rapid. Hydrological analyses showed that flow conditions have created ideal blackfly larval habitat in this rapid, with prolonged uninterupted periods (&gt;3 months) exceeding this threshold. A model was developed to predict probabilities and severities of blackfly outbreaks, based on flow periods and water temperatures, both of which determine the success and duration respectively of the aquatic phase of S. chutteri. July was identified as the critical month for flow restriction to 2 m3 s−1 for a period of 38 days, in order to reduce the winter populations of S. chutteri in the Great Fish River at the study site and avoid the typical spring outbreaks of blackfly. Copyright © 2008 John Wiley &amp; Sons, Ltd.

Shot hole encourages almond drop, doesn't harm kernels

Severe spring outbreaks of shot hole disease are often accompanied by leaf fall and fruit drop. Although fruit are shed in response to defoliation, the direct effect of shot hole infection on developing fruit was not known. When fruit at various stages of development were inoculated with high concentrations of the shot hole pathogen, very young and midsized fruit fell, whereas older fruit were retained. Typical shot hole lesions developed on midsized fruit, and full-sized fruit became resistant to infection when embryo development began. Infection did not affect kernel weight, but caused a slight, economically unimportant reduction in kernel length.

Climate and outbreaks of the forest tent caterpillar

Some have suggested that the periodic outbreaks of the forest tent caterpillar. Malacosoma disstria are triggered by weather the temperature at the time of early larval feeding, and overwintering temperatures To assess the role of these factors, defoliation maps, compiled annually from flight surveys for the province of Ontario. were compared to similarly scaled temperature records An analysis of the year to year variation shows no relationship between the pattern of increases or declines in defoliation and either temperatures during early larval development, or overwintering temperatures Four periods of defoliation by forest tent caterpillars were observed in Ontario over 41 yr. but at individual sites extensive defoliation did not occur for each of the outbreak periods Defoliation was less severe in regions with low overwintering temperatures, but was not related to the average number of degree days m the early spring Outbreaks were most common in areas where deciduous forests were extensive, and the mean overwintering temperatures were above −40°C While these weather variables do not apparently explain the details of population dynamics of forest tent caterpillars, extreme weather conditions might synchronize populations

Disponibilités et utilisation des ressources par le Magot Macaca sylvanus dans différents milieux en Algérie

A quantitative study of the vegetation structure, and of the seasonal variations of resource availability, was carried out from February 1983 to January 1987 in a deciduous Oak forest (Akfadou) and in an evergreen Cedar-Oak forest (Djurdjura). The diet of the two troops of Barbary macaques living in the same areas was studied at the same time. The results of these two simultaneous investigations are here compared. The tree and shrub cover were found to be less important, and the food resources more varied, in Djurdjura than in Akfadou. Great seasonal variations in resource availability were found in both habitats. However, food production was more evenly spread over the whole year in Djurdjura than in Akfadou. The most critical period of the year, in terms of food availability, took place in summer (mostly in June) in Akfadou. The mature Cedar leaves became an important item in the monkeys’ diet during the winter in Djurdjura, when snow covers the ground. The spring outbreaks of geometrid caterpillars were more frequent in Akfadou than in Djurdjura ; their major consequence was to induce a lower acorn production the following autumn. By and large, the Cedar-Oak forest appears to be a more favourable habitat for the Barbary macaque than the deciduous Oak forest. Great seasonal variations in diet were noticeable, the macaques successively shifting from a mostly insectivorous diet to a granivorous, and finally to a folivorous diet, as the season advanced. These seasonal variations were dependent on the spring caterpillar’s outbreaks. The Barbary macaques of Djurdjura fed more on plants of the herbaceous layer (58.4 %) than those of Akfadou (37.1 %) ; they also ate more leaves (48.1 % and 26.7 % respectively), and less seeds, particularly acorns (26.7 % and 32.1 % respectively). The Barbary macaque is generally considered as an eclectic feeder. This is true. However, they definitively select their food items. Only 47 % (Akfadou) and 48 % (Djurdjura) of the available plant species were included in their diet, and available plants could be easily allocated to three distinct categories : those which were preferred, those which were avoided, and the « neutral » ones, according to their « selection ratio ». The herbaceous species were favourites in both habitats throughbout the year. The Djurdjura Barbary macaques avoided a smaller proportion of the available plant species (8 %) than those of Akfadou (11 %), and a larger number of species were selectively searched for (9 % and 7 % respectively). The leaves of herbaceous plants made up 18 % of the annual diet of monkeys in Akfadou. Within the species pool, the leaves of 10 % of the species were avoided (i.e. 82 % of the plant resources available). On the contrary, the same leaves made up 35 % of the annual diet in Djurdjura, 6 % only of the species being avoided (i.e. 61 % of the available species). There was also a definite selection of certain plant parts. The macaques’ food choices obviously depend as much on the availability and nature of the existing food items as on the animals nutritional requirements at various times of the year. Moreover, any environmental change furthering the growth of avoided plant species in a given area can influence the Barbary macaque populations. This is well in agreement with our previous findings on the population dynamics of our monkeys showing that their reproductive success is higher in the Cedar forest troop than in the others (Ménard et al., 1985, 1986). We therefore agree with Taub (1977) who considers the Cedar forest as the habitat most suitable for Macaca sylvanus.

Ribavirin Therapy of Respiratory Syncytial Virus

Ribavirin is an antiviral drug that has recently been approved by the FDA in an aerosolized form for the therapy of respiratory syncytial virus infections in hospitalized children who do not require assisted ventilation. Ribavirin is different from other antiviral drugs both in its spectrum of activity and in its mode of administration.1,2 The following statement is presented to identify which children should be considered for ribavirin therapy. Questions also have arisen as to the benefits afforded by treatment in comparison to the potential unknown toxicity of the drug and as to whether ribavirin should be administered to infants who require assisted ventilation; the package insert has warned against using the drug in such patients. Whether pregnant women or personnel who care for infants being treated with ribavirin are at risk from exposure to the drug is also of concern. Finally, physicians must be aware that the cost of ribavirin needed for three days of therapy is almost $700. BACKGROUND Respiratory Syncytial Virus Disease Respiratory syncytial virus is the most important cause of lower respiratory tract disease in infants and young children. It usually appears in yearly winter to spring outbreaks and infects essentially all children during their first 3 years of life. The number of infected infants who require hospitalization has been estimated to range in different locations from one in 50 to one in 1,000. Currently, the mortality in hospitalized infants who were previously normal is low, less than 1%.3 In infants with underlying diseases, however, the mortality may be strikingly higher.3-5

Myxomatosis: the occurrence of antibody to a soluble antigen of myxoma virus in wild rabbits, Oryctolagus cuniculus (L.), in Victoria, Australia.

The occurrence of antibody of myxoma virus in wild rabbits following epizootics is highest in the semi-arid north-west of Victoria and lowest in temperate southern Victoria. Occurrence ranges up to about 90% in the north-west and to about 70% in the south except on the Western Plains where epizootics are rare and antibody occurrence seldom exceeds 30%. The establishment of the European rabbit flea may be changing the pattern of occurrence of antibody in the north-west by causing spring outbreaks of myxomatosis. It is suggested that the effects of the replacement of a simple recurring system of epizootic and breeding season several months apart by the occurrence of myxomatosis twice in the same year, once coincident with the breeding season, will be complex. The occurrence of detectable antibody may be less dependent on the infection rate and may be dependent to some extent on the relative timing of spring myxomatosis and the breeding season.

Lead Poisoning of Waterfowl in Wisconsin

The presence, prevalence, and significance of lead poisoning as a mortality factor of wild waterfowl in Wisconsin is reviewed. Since 1940, more than 1700 Canada geese (Branta canadensis) have succumbed to lead poisoning in Wisconsin. This surpasses the total Canada goose mortality due to lead poisoning reported in the literature for North America. Although the majority of lead poisoning outbreaks among geese occurred in the spring, total mortality was equally distributed between fall and spring outbreaks. Lead poisoning mortality among whistling swans (Olor columbianus) in Wisconsin annually takes a small number of the spring migrating population. Seven duck species were known victims of lead poisoning in Wisconsin, but this disease was not considered an important mortality factor of ducks in the state. The mallard (Anas platyrhynchos) was the major target of the disease. Some of the ecological factors found to be involved with lead poisoning of waterfowl in Wisconsin were climate, water levels, soil types, diet, and the timing of waterfowl migrations. The signs, pathological lesions, epizootiology, and significance of lead poisoning of waterfowl in Wisconsin were considered and discussed. 18 references.

Studies on cereal mildew in Britain

Overwintering cleistocarps of Erysiphe graminis do not contribute to spring outbreaks of cereal mildew in this country. Ascospores, shed from July to late September, are the source of infection for successive crops of winter wheat and barley, but conidia from infected late tillers are the chief source for winter oats. Ascospore differentiation only takes place under high moisture, following the completion of a ‘ripe-to-spore’ stage. Optimum conditions for this are located at the base of the straws and the stubbles are the main source of the ascospore shower. The intensity of the shower in any season is related to the environmental conditions during the growth of the crop and the degree of humidity at and following harvest. Direct infection of autumn-sown cereals may occur but more generally it derives from stubble volunteer seedlings infected by the ascospores. The timing of the ascospore shower and the extent to which volunteer seedlings develop on the stubbles determine the incidence of mildew in early-sown winter cereals, but susceptibility to disease decreases as the date of sowing is delayed. Although existing lesions continue growth and sporulation, during the winter there is little further spread of infection through the crops. The incidence of infection foci for the build-up of mildew in spring is thus dependent upon the climatic conditions prevailing during the previous year and the extent and timing of the autumn cultivations.