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Impacts of hurricanes and disease on Diadema antillarum in shallow water reef and mangrove locations in St John, USVI.

The 1983-1984 mortality event of the long-spined sea urchin Diadema antillarum reduced their population by up to 99% and was accompanied by a phase shift from coral dominated to algal dominated reefs in the Caribbean. Modest rebounds of D. antillarum populations in the Caribbean have been noted, and here we document the impacts of two major hurricanes (2017, Irma and Maria) and the 2022 disease outbreak on populations of D. antillarum found by targeted surveys in the urchin zone at nine fringing reef and three mangrove sites on St. John, USVI. D. antillarum populations at the reef sites had de

[Progress on the application of respondent-driven sampling in population size estimation].

Respondent-driven sampling (RDS) is a method of sampling specifically for hidden populations, often applied to transgender women, female sex workers, men who have sex with men, and other groups that are difficult to identify and contact because of stigma and legal constraints. However, this method is gradually applied to the general population. With the continuous improvement of RDS, studies find that the network size of RDS samples can be weighted to estimate the overall situation and population size. This article summarizes the current application progress of RDS in population size estimatio

Aedes albopictus bionomics data collection by citizen participation on Procida Island, a promising Mediterranean site for the assessment of innovative and community-based integrated pest management methods.

In the last decades, the colonization of Mediterranean Europe and of other temperate regions by Aedes albopictus created an unprecedented nuisance problem in highly infested areas and new public health threats due to the vector competence of the species. The Sterile Insect Technique (SIT) and the Incompatible Insect Technique (IIT) are insecticide-free mosquito-control methods, relying on mass release of irradiated/manipulated males, able to complement existing and only partially effective control tools. The validation of these approaches in the field requires appropriate experimental settings

Prevalence of bovine trypanosomosis and vector density in a dry season in Gamo-Gofa and Dawuro Zones, Southern Ethiopia.

Trypanosomosis remains one of the biggest constraints of livestock productivity in sub-Saharan Africa. It is of particular concern in Ethiopia where crop production is largely dependent on animal traction power. This study was conducted between November 2015 and March 2016 to estimate the prevalence of bovine trypanosomosis and vector density in Gamo-Gofa and Dawuro Zones located in Southern Ethiopia. For the entomological survey, a total of 305 NGU traps were deployed for three consecutive days at different positions in the two study areas. For parasitological study, blood samples were collec

Phylogeography, genetic diversity, and population structure of Nile crocodile populations at the fringes of the southern African distribution.

Nile crocodiles are apex predators widely distributed in sub-Saharan Africa that have been viewed and managed as a single species. A complex picture of broad and fine-scale phylogeographic patterns that includes the recognition of two species (Crocodylus niloticus and Crocodylus suchus), and the structuring of populations according to river basins has started to emerge. However, previous studies surveyed a limited number of samples and geographical regions, and large areas of the continent remained unstudied. This work aimed at a fine scale portrait of Nile crocodile populations at the fringes

The association between temperature variability and cause-specific mortality: Evidence from 47 Japanese prefectures during 1972-2015.

BACKGROUND: In the context of climate change, extreme temperature events are known to be associated with increased mortality risk. However, data about the mortality risk related to temperature variability (TV) accounting for both intra- and inter-day variations in temperature are limited. OBJECTIVES: The present study aims to quantify the associations between TV and cause-specific mortality in Japan, evaluate whether the effects of TV are modified by prefecture-level characteristics and examine the temporal trend in mortality risk of TV. METHODS: Data on daily all-cause and 11 cause-specific

Getting more from heterogeneous HIV-1 surveillance data in a high immigration country: estimation of incidence and undiagnosed population size using multiple biomarkers.

BACKGROUND: Most HIV infections originate from individuals who are undiagnosed and unaware of their infection. Estimation of this quantity from surveillance data is hard because there is incomplete knowledge about (i) the time between infection and diagnosis (TI) for the general population, and (ii) the time between immigration and diagnosis for foreign-born persons. METHODS: We developed a new statistical method for estimating the incidence of HIV-1 and the number of undiagnosed people living with HIV (PLHIV), based on dynamic modelling of heterogeneous HIV-1 surveillance data. The methods c

Спатиовременные характеристики и основные факторы, влияющие на типичные эпидемии лихорадки денге в Китае.

БАКГРЕСС: лихорадка Денге (ДФ) является широко распространенным вирусным инфекционным заболеванием, передаваемым через комары в мире, и все более серьезные эпидемии ДФ в Китае в последние годы серьезно сказались на здоровье людей. Таким образом, для укрепления эффективных мер по предупреждению этих региональных эпидемий и борьбе с ними решающее значение имеет изучение динамики и потенциальных факторов воздействия на них в типичных регионах. МЕТОДЫ: Для выявления потенциальных факторов, влияющих на традиционно-временную эпидемию в типичных эпидемических регионах Китая (например, Дельта реки Пёр

Совпадение в аннотации оригинала
BACKGROUND: Dengue fever (DF) is a common mosquito-borne viral infectious disease in the world, and increasingly severe DF epidemics in Chin … NDVI), temperature, precipitation, and humidity, in conjunction with socioeconomic factors, such as population density (Pop), road density, land-use, and gross domestic product, were employed. RESULTS: DF epidemics in the PRD and BYM exhibit prominent spatial variations at 4 km and 3 km grid scales, characterized by significant spatial clustering over the Guangzhou …

Wing morphometrics of Aedes (Ochlerotatus) albifasciatus (Macquart, 1838) (Diptera: Culicidae) from different climatic regions of Argentina.

BACKGROUND: Gene flow restrictions between populations of Aedes albifasciatus, the vector of Western equine encephalitis and Dirophilaria immitis, have been described in the central region of Argentina. Genetic and eco-physiological variations usually result in local forms reflecting the climatic regions. Mosquito wings and their different parts have ecological functions in flight and communication. Therefore, wing shape could be considered an aspect of sexual dimorphism, and its eco-physiological responses can be expressed as morphological changes induced by the environment. METHODS: To comp

High Triatoma brasiliensis Densities and Trypanosoma cruzi Prevalence in Domestic and Peridomestic Habitats in the State of Rio Grande do Norte, Brazil: The Source for Chagas Disease Outbreaks?

AbstractA total of 2,431 Triatoma brasiliensis were collected from 39 populations of Paraíba (PB) and Rio Grande do Norte (RN) states, Brazil. In PB, Trypanosoma cruzi infection was not detected in either peridomestic or domestic vector populations. In contrast, in RN, T. brasiliensis was detected with high parasite prevalence in these ecotopes (30.7-40.0%). Moreover, peridomicile insect population densities were more than double the average densities of all other settings evaluated (19.17 versus < 8.94 triatomine/man-hour). Genotyped parasites evidenced a mix of T. cruzi lineages circulating

Seasonal cycles of the TBE and Lyme borreliosis vector Ixodes ricinus modelled with time-lagged and interval-averaged predictors.

Ticks of the species Ixodes ricinus (L.) are the major vectors for tick-borne diseases in Europe. The aim of this study was to quantify the influence of environmental variables on the seasonal cycle of questing I. ricinus. Therefore, an 8-year time series of nymphal I. ricinus flagged at monthly intervals in Haselmühl (Germany) was compiled. For the first time, cross correlation maps were applied to identify optimal associations between observed nymphal I. ricinus densities and time-lagged as well as temporal averaged explanatory variables. To prove the explanatory power of these associations,

Host, habitat and climate preferences of Ixodes angustus (Acari: Ixodidae) and infection with Borrelia burgdorferi and Anaplasma phagocytophilum in California, USA.

The Holarctic tick Ixodes angustus is a competent vector for Borrelia burgdorferi, the etiologic agent of Lyme disease, and possibly Anaplasma phagocytophilum, the etiologic agent of granulocytic anaplasmosis, as well. From 2005 to 2013, we collected host-feeding I. angustus individuals from live-trapped small mammals and by flagging vegetation from 12 study sites in northern and central California, and tested for B. burgdorferi sensu lato, A. phagocytophilum, and Rickettsia spp. DNA by real-time PCR. Among 261 I. angustus collected (259 from hosts and two by flagging), the most common hosts w

Presence of human noroviruses on bathroom surfaces: a review of the literature.

Enteric viruses are the most common cause of acute gastroenteritis worldwide with most cases of illness attributed to caliciviruses, such as … es reported detection rates of 2-17 %. Factors associated with HuNoV presence in bathrooms included population density, setting type, employee numbers, food handler knowledge, awareness, and behaviours, and cleaning/disinfecting procedures. Our review suggests bathrooms could be vehicles that transmit HuNoV under both outbreak and non-outbreak conditions.

Optimal strategies for controlling riverine tsetse flies using targets: a modelling study.

BACKGROUND: Tsetse flies occur in much of sub-Saharan Africa where they transmit the trypanosomes that cause the diseases of sleeping sickness in humans and nagana in livestock. One of the most economical and effective methods of tsetse control is the use of insecticide-treated screens, called targets, that simulate hosts. Targets have been ~1 m2, but recently it was shown that those tsetse that occupy riverine situations, and which are the main vectors of sleeping sickness, respond well to targets only ~0.06 m2. The cheapness of these tiny targets suggests the need to reconsider what intensit

Climate change and the emergence of vector-borne diseases in Europe: case study of dengue fever.

BACKGROUND: Dengue fever is the most prevalent mosquito-borne viral disease worldwide. Dengue transmission is critically dependent on climat … bles (maximum temperature, minimum temperature, precipitation, humidity) and socioeconomic factors (population density, urbanisation, GDP per capita and population size), under contemporary conditions (1985-2007) in Mexico. We then used our model estimates to project dengue incidence under baseline conditions (1961-1990) and three climate change scenarios: short-ter …

Host group formation decreases exposure to vector-borne disease: a field experiment in a 'hotspot' of West Nile virus transmission.

Animals can decrease their individual risk of predation by forming groups. The encounter-dilution hypothesis extends the potential benefits of gregariousness to biting insects and vector-borne disease by predicting that the per capita number of insect bites should decrease within larger host groups. Although vector-borne diseases are common and can exert strong selective pressures on hosts, there have been few tests of the encounter-dilution effect in natural systems. We conducted an experimental test of the encounter-dilution hypothesis using the American robin (Turdus migratorius), a common

The sequential aerosol technique: a major component in an integrated strategy of intervention against Riverine Tsetse in Ghana.

BACKGROUND: An integrated strategy of intervention against tsetse flies was implemented in the Upper West Region of Ghana (9.62°-11.00° N, 1.40°-2.76° W), covering an area of ≈18,000 km(2) within the framework of the Pan-African Tsetse and Trypanosomosis Eradication Campaign. Two species were targeted: Glossina tachinoides and Glossina palpalis gambiensis. METHODOLOGY/PRINCIPAL FINDINGS: The objectives were to test the potentiality of the sequential aerosol technique (SAT) to eliminate riverine tsetse species in a challenging subsection (dense tree canopy and high tsetse densities) of the tot

Spatial and temporal variations relevant to tsetse control in the Bipindi focus of southern Cameroon.

BACKGROUND: Human African Trypanosomiasis (HAT) remains a public health problem in many poor countries. Due to lack of financial resources in these countries, cost-effective strategies are needed for efficient control of this scourge, especially the tsetse vector. It was shown that perennial water sources maintain a favourable biotope for tsetse flies and thus the transmission dynamics of sleeping sickness. The present paper aimed at assessing the transmission dynamics of HAT in a forest environment where the hydrographic network is important. METHODS: Two entomological surveys were carried o

Does high biodiversity reduce the risk of Lyme disease invasion?

BACKGROUND: It has been suggested that increasing biodiversity, specifically host diversity, reduces pathogen and parasite transmission amongst wildlife (causing a "dilution effect"), whereby transmission amongst efficient reservoir hosts, (e.g. Peromyscus spp. mice for the agent of Lyme disease Borrelia burgdorferi) is reduced by the presence of other less efficient host species. If so, then increasing biodiversity should inhibit pathogen and parasite invasion. METHODS: We investigated this hypothesis by studying invasion of B. burgdorferi and its tick vector Ixodes scapularis in 71 field si