Risk Of Disease Transmission Research Articles

Zoonotic Surveillance of Bartonella spp.: Exploring the Public Health Risks in Human Settlements.

Urban rodents are reservoirs of zoonotic pathogens, including Bartonella spp., which are transmitted by ectoparasites such as fleas. Zoonotic diseases caused by Bartonella often go undocumented due to confusing or subtle clinical symptoms, lack of awareness and poor diagnosis. This study aimed to assess the prevalence and diversity of Bartonella spp. by screening free-ranging rodents and their ectoparasites in the unique ecological settings of Alipore Railway Station, Kolkata, India. The station's high passenger traffic and proximity to food stalls create favourable conditions for rodents and fleas to thrive, increasing the risk of zoonotic transmission. Rodents and fleas were identified by morphological features and DNA sequencing. Detection of Bartonella was carried out by DNA sequencing of citrate synthase (gltA) gene. Phylogenetic relationships among the obtained sequences were inferred through phylogenetic tree and haplotype network analyses. Q-PCR testing from human samples from the surrounding area was performed to confirm the zoonotic transfer potential. Of 60 rodents, identified as Bandicota indica 28 (46.7%) and Bandicota bengalensis 32 (53.3%), and 110 fleas (Xenopsylla cheopis) were collected. The prevalence of Bartonella infection varied across three different hosts, that is, 32/60 rodents (53.33%), 87/110 fleas (79.1%) and 4/25 human (16%). Phylogenetic analysis revealed four distinct Bartonella lineages comprising 11 novel haplotypes (H1-H11), with haplotype H4 shared between rodents, fleas and humans, indicating active and cross species transmission of Bartonella spp. Haplotype H10, identified as B. rochalimae, was a phylogenetically diverged lineage exclusively found in fleas, suggesting a potentially novel lineage. The results highlight the significant public health risks posed by Bartonella spp. in densely populated urban areas, particularly in environments like railway stations where human-rodent interactions are frequent. This study underscores the necessity of integrated pest management and surveillance strategies, using molecular tools such as Q-PCR, to mitigate the risk of zoonotic disease transmission in urban settings.

The Impact of Seasonal Influenza in Reducing the Spread of Diseases in the Kingdom of Saudi Arabia

Seasonal influenza remains a significant public health concern globally, with its impact extending beyond the direct effects of the virus. In the Kingdom of Saudi Arabia, where unique climatic conditions and high-density population events, such as the Hajj and Umrah pilgrimages, create an elevated risk for disease transmission, influenza management has become a critical focus. This study examines the indirect benefits of seasonal influenza control measures in reducing the spread of other infectious diseases within the Kingdom. Drawing on epidemiological data, vaccination coverage reports, and public health policies, the study highlights the role of widespread influenza vaccination campaigns, particularly among high-risk populations such as healthcare workers, the elderly, and pilgrims. The findings reveal a significant correlation between high influenza vaccine uptake and the reduced incidence of respiratory infections, such as pneumonia and bronchitis, and a decline in healthcare utilization during peak seasons. Furthermore, the seasonal influenza vaccination program has enhanced public health awareness, improved disease surveillance infrastructure, and strengthened healthcare preparedness, contributing to the mitigation of other communicable diseases. This study also explores the broader implications of integrating influenza management strategies into Saudi Arabia’s public health framework, including the development of herd immunity and reduced economic burdens on healthcare systems. By showcasing the Kingdom’s efforts in combating influenza and its indirect benefits, the study underscores the importance of sustained investment in vaccination campaigns and the adoption of a comprehensive approach to disease prevention.

Spatial dynamics of Culex quinquefasciatus abundance: geostatistical insights from Harris County, Texas

Mosquito-borne diseases pose a significant public health threat, prompting the need to pinpoint high-risk areas for targeted interventions and environmental control measures. Culex quinquefasciatus is the primary vector for several mosquito-borne pathogens, including West Nile virus. Using spatial analysis and modeling techniques, we investigated the geospatial distribution of Culex quinquefasciatus abundance in the large metropolis of Harris County, Texas, from 2020 to 2022. Our geospatial analysis revealed clusters of high mosquito abundance, predominantly located in central Houston and the north-northwestern regions of Harris County, with lower mosquito abundance observed in the western and southeastern areas. We identified persistent high mosquito abundance in some of Houston’s oldest neighborhoods, highlighting the importance of considering socioeconomic factors, the built environment, and historical urban development patterns in understanding vector ecology. Additionally, we observed a positive correlation between mosquito abundance and neighborhood-level socioeconomic status with the area deprivation index explaining between 22 and 38% of the variation in mosquito abundance (p-value < 0.001). This further underscores the influence of the built environment on vector populations. Our study emphasizes the utility of spatial analysis, including hotspot analysis and geostatistical interpolation, for understanding mosquito abundance patterns to guide resource allocation and surveillance efforts. Using geostatistical analysis, we discerned fine-scale geospatial patterns of Culex quinquefasciatus abundance in Harris County, Texas, to inform targeted interventions in vulnerable communities, ultimately reducing the risk of mosquito exposure and mosquito-borne disease transmission. By integrating spatial analysis with epidemiologic risk assessment, we can enhance public health preparedness and response efforts to prevent and control mosquito-borne disease.

Modelling the effectiveness of antiviral treatment strategies to prevent household transmission of acute respiratory viruses.

Households are a major driver of transmission of acute respiratory viruses, such as SARS-CoV-2 or Influenza. Until now antiviral treatments have mostly been used as a curative treatment in symptomatic individuals. During an outbreak, more aggressive strategies involving pre- or post-exposure prophylaxis (PrEP or PEP) could be employed to further reduce the risk of severe disease but also prevent transmission to household contacts. In order to understand the effectiveness of such strategies and the factors that may modulate them, we developed a multi-scale model that follows the infection at both the individual-level (viral dynamics) and the population-level (transmission dynamics) in households. Using a simulation study we explored different antiviral treatment strategies, evaluating their effectiveness on reducing the transmission risk and the virological burden in households for a range of virus characteristics (e.g., secondary attack rate-SAR, or time to peak viral load). We found that when the index case can be identified and treated before symptom onset, both transmission and virological burden are reduced by > 75% for most SAR values and time to peak viral load, with minimal benefit to treat additionally household contacts. While treatment initiated after index symptom onset does not reduce the risk of transmission, it can still reduce the virological burden in the household, a proxy for severe disease and subsequent transmission risk outside the household. In that case optimal strategies involve treatment of both index case and household contacts as PEP, with efficacy > 50% when peak viral load occurs after symptom onset, and 30-50% otherwise. In all the considered cases, antiviral treatment strategies were optimal for SAR ranging 20-60%, and for larger household sizes. This study highlights the opportunity of antiviral drug-based interventions in households during an outbreak to minimize viral transmission and disease burden.

In-vehicle air quality in public buses during real-world trips in Kathmandu Valley, Nepal

Urban air quality shows notable variability across various microenvironments. Transport-related microenvironments often have one of the highest air pollution levels, where commuters have significant exposure to air pollutants. In Kathmandu Valley (KV), Nepal, passengers’ exposure to air pollutants in such microenvironments remain a poorly understood issue. In this study, we analyzed cabin air quality and ventilation rates in public buses operated in KV. In-cabin and in-route ambient air pollution levels were monitored during real-world bus operations in 32 trips on a test route selected in the core city area. A CO2 mass balance model was applied to estimate cabin ventilation rates. The mean in-cabin and outdoor PM2.5 concentrations were 95.9 ± 40.4 (mean ± standard deviation) and 94.7 ± 32.4 μg/m3, respectively. Likewise, mean in-cabin and outdoor PM1 concentrations were 72.5 ± 31.3 and 69.7 ± 25.3 μg/m3, respectively, with mean PM1 to PM2.5 ratio >0.75, indicating that a majority of particle mass was in the sub-micron size range, which is often more health-hazardous. We estimated passengers’ inhalation dose for PM2.5 and PM1 as 5.65 ± 2.32 and 4.27 ± 1.79 μg/km, respectively. Among various factors considered, traffic hour significantly affected both in-cabin and ambient particulate matter concentrations. The trip-average in-cabin CO2 concentration ranged from 513 to 1230 ppm, whereas cabin ventilation rates ranged from 8.0 to 72.4 L/s/person. Ventilation levels in a majority of bus trips were inadequate, especially considering the recommended thresholds to reduce the transmission risk of airborne diseases. Setting standards for ventilation and air conditioning systems in public buses is crucial to ensure thermal comfort, protect bus commuters from the harmful impacts of air pollution, and to improve public transport services in KV.

Transmission risk of vector-borne bacterial diseases (Anaplasma spp. and Ehrlichia canis) in Spain and Portugal

BackgroundEhrlichiosis and anaplasmosis are vector-borne bacterial diseases produced by intracellular rickettsial species of the genus Ehrlichia and Anaplasma. Ehrlichia canis and Anaplasma spp. (A. platys and A. phagocytophilum) have reported cases of zoonotic transmision and are the main bacterial agents of canine ehrlichiosis and anaplasmosis. They normally present an asymptomatic or mild course in domestic and wild animals with some lethal cases reported. The main vector of these diseases in Europe are the castor bean tick (Ixodes ricinus) and the brown dog tick (Rhipicephalus sanguineus), although only in the latter, the main host is the domestic dogs. The aim of this work is to apply an integrative approach to convert ecological niche models (ENMs) into potential transmission risk models and understand the relative contribution of the two potential vectors (R. sanguineus and I. ricinus) to spread both diseases in the Iberian Peninsula and Balearic Islands.ResultsTwo ENMs meeting all criteria were successfully generated for R. sanguineus and I. ricinus with human footprint being the most relevant explanatory variable. The novelty of the study lies in the combination of independent ENMs for both species to estimate the disease transmission risk of specific bacteria (E. canis, A. platys and A. phagocytophilum). Only the transmission risk maps that had higher contribution of R. sanguineus than I. ricinus showed relevant and positive significant correlations between risk and seroprevalence in either of the two species of bacteria (R ≥ 0.4; p < 0.05). Regarding Anaplasma spp., the map having 10% contribution of I. ricinus (10I) and 90% of R. sanguineus (90R) inferred 47.4% of infected dogs in very high-risk areas. In the case of E. canis, the model showing a proportion of 25I-75R showed better validation power (53.4% of infected dogs in very high-risk areas).ConclusionThe validation approach used in this study produced a good approximation to understand the relative contribution of the two tick species in bacterial disease transmission in dogs in the Iberian Peninsula and Balearic Islands. Rhipicephalus sanguineus appears as the main transmitter of both diseases in the study area (90% and 75% for anaplasmosis and ehrlichiosis respectively), in accordance with its higher abundance and host preference. This estimate may help veterinary staff, clinicians and owners to optimize the control of these diseases in certain vulnerable areas, and thus reduce the risk of infection in risk areas.

Unveiling mechanistic intricacies of Chlorella pyrenoidosa-mediated pathogen removal from sewage

Amidst the global sanitation challenges of water pollution, waterborne diseases, and the alarming presence of pathogens in disinfected water, microalgal technology has emerged as a viable alternative for wastewater treatment. Recently, the ability of microalgae to remove pathogens from wastewater has been highlighted. However, a critical knowledge gap exists regarding microalgae-mediated pathogen removal mechanisms. The present study uncovers the intricate mechanisms of Chlorella pyrenoidosa-mediated Escherichia coli removal from sewage. Microalgae-induced pH increase was identified as the most crucial mechanism, followed by photooxidation and attachment, mediated by the hydroxyl group. Longer photoperiods or ultraviolet irradiation produced high oxidative stress, promoting microalgal exopolysaccharides’ production and increasing pathogen entrapment. The knowledge of crucial removal mechanisms can be harnessed for the development of more efficient, innovative, and scalable microalgal systems. Such improved systems offer a sustainable solution to address water-related issues by improving wastewater treatment, increasing access to clean water, and reducing the transmission risk of waterborne diseases.

Swine Industry in Canada: Biosecurity in Live Animal, Semen Transportation, and Embryo Transfer

The pork industry, a key player in the Canadian economy, significantly contributes to livestock production, international trade markets, and employment. The multi-faceted swine industry is comprised of nucleus, multiplier, and commercial herds. The recognition and application of exemplary internal and external biosecurity measures are paramount for maintaining sustainable swine production. Historically, live animal transport has been an important means of disseminating superior genetics between production herds and poses a considerable risk for disease transmission and biosecurity breach points. The industry has evolved over time to employ other methods, through the shipping of boar semen and the adoption of artificial insemination practices to acquire genetic resources with a lower risk of disease transmission. These effective changes have led to an improvement in herd health, production performance, and efficiency. In particular, the industry&amp;rsquo;s dedication to enhanced biosecurity is evident in the effort to streamline embryo collection and transfer procedures. Such advances reduce the potential need to transport live animals, thereby lowering the risk of introducing infectious agents. This review article explores the different forms of disseminating swine genetics, namely, live animal, semen transportation, and embryo transfer, examining potential breaches in biosecurity, and discussing mitigation strategies that reduce disease transmission to protect the health of animal stock.

LNC-ing Genetics in Mitochondrial Disease.

Primary mitochondrial disease (MD) is a group of rare genetic diseases reported to have a prevalence of 1:5000 and is currently without a cure. This group of diseases includes mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS), maternally inherited diabetes and deafness (MIDD), Leber's hereditary optic neuropathy (LHON), Leigh syndrome (LS), Kearns-Sayre syndrome (KSS), and myoclonic epilepsy and ragged-red fiber disease (MERRF). Additionally, secondary mitochondrial dysfunction has been implicated in the most common current causes of mortality and morbidity, including cardiovascular disease (CVD) and cancer. Identifying key genetic contributors to both MD and secondary mitochondrial dysfunction may guide clinicians to assess the most effective treatment course and prognosis, as well as informing family members of any hereditary risk of disease transmission. Identifying underlying genetic causes of primary and secondary MD involves either genome sequencing (GS) or small targeted panel analysis of known disease-causing nuclear- or mitochondrial genes coding for mitochondria-related proteins. Due to advances in GS, the importance of long non-coding RNA (lncRNA) as functional contributors to the pathophysiology of MD is being unveiled. A limited number of studies have thus far reported the importance of lncRNAs in relation to MD causation and progression, and we are entering a new area of attention for clinical geneticists in specific rare malignancies. This commentary provides an overview of what is known about the role of lncRNAs as genetic and molecular contributors to disease pathophysiology and highlights an unmet need for a deeper understanding of mitochondrial dysfunction in serious human disease burdens.

Geospatial Analysis of Malaria and Typhoid Prevalence Due to Waste Dumpsite Exposure in Kinshasa Districts with and Without Waste Services: A Case Study of Bandalungwa and Bumbu, Democratic Republic of Congo.

Municipal solid waste (MSW) management poses substantial challenges in rapidly urbanizing areas, with implications for both the environment and public health. This study focuses on the city of Kinshasa in the Democratic Republic of Congo, investigating whether the presence or absence of solid waste collection services results in varying health and economic impacts, and additionally, seeking to establish a correlation between residing in proximity to dumpsites and the prevalence of diseases like malaria and typhoid, thereby providing a comprehensive understanding of the health implications tied to waste exposure. Health data were collected through survey questionnaires, and the geospatial distribution of 19 dumpsites was analyzed using Google Earth Pro 7.3.1 for satellite imagery and GIS software 10.3.1 to map dumpsites and define 1 km buffer zones around the largest dumpsites for household sampling. Statistical analyses were conducted using R Version 4.2.3, employing Chi-square tests for disease prevalence and logistic regression to assess associations between waste management practices and health outcomes. A multivariate regression was used to evaluate correlations between discomfort symptoms (e.g., nasal and eye irritation) and waste activities. The geospatial analysis revealed significant variation in dumpsite size and location, with larger dumpsites near water bodies and flood-prone areas. The study contributes valuable insights into waste-related health risks, emphasizing the need for improved waste management policies in rapidly urbanizing areas like Kinshasa. The socio-demographic analysis reveals distinct traits within the surveyed populations of two communes, Bandalungwa (Bandal) and Bumbu. Bumbu, characterized by larger open dumpsites and limited waste collection services, exhibits a higher prevalence of certain diseases, particularly typhoid fever, and malaria. This discrepancy is statistically significant (p < 2.2 × 10-16), suggesting a potential link between waste exposure and disease prevalence. In Bandal, self-waste collection is a high risk of exposure to typhoid (OR = 4.834 and p = 0.00001), but the implementation of a waste collection service shows protective effect (OR = 0.206 and p = 0.00001). The lack of waste collection services in Bumbu increases the risk of exposure, although not significantly (OR = 2.268 and p = 0.08). Key findings indicate that waste disposal methods significantly differ between Bandal and Bumbu. Bumbu's reliance on burning and dumping creates environments conducive to disease vectors, contributing to elevated disease transmission risks. However, an in-depth correlation analysis reveals that specific waste management practices, such as burning, burying, and open dumping, do not exhibit statistically significant associations with disease prevalence, underlining the complexity of disease dynamics. This study contributes valuable insights into the importance for urban public health, particularly in rapidly urbanizing cities like Kinshasa, where inadequate waste management exacerbates health risks. By investigating the correlation between proximity to unregulated dumpsites and the prevalence of diseases such as malaria and typhoid fever, the research underscores the urgent need for targeted waste management policies. The stark health disparities between Bandal, with better waste services, and Bumbu, where services are lacking, highlight the protective effect of organized waste collection. These findings suggest that expanding public waste services and enforcing stricter regulations on waste disposal could reduce disease prevalence in vulnerable areas. Additionally, the study supports integrating waste management into urban planning as a critical public health measure. Its evidence-based approach offers valuable insights for policymakers in Kinshasa and other cities facing similar challenges, emphasizing the broader health implications of environmental governance in urban settings.

PREVALENCE OF SNAIL VECTORS OF SCHISTOSOMIASIS ALONG ANTAU RIVER, KEFFI, NASARAWA STATE

Schistosomiasis, or bilharzia, is a parasitic disease that affects over 230 million people worldwide, with 700 million at risk, primarily in tropical and subtropical regions, including Nigeria. The disease is transmitted through freshwater snails that host Schistosoma parasites. This study aims to understand the prevalence of snail vectors responsible for transmitting schistosomiasis along Antau River, Keffi, Nasarawas State. A snail sampling survey conducted at three locations - Saura Bridge, Antau Bridge, and Mannu Bridge - along Antau River yielded a total of 216 snails. The distribution showed Saura Bridge with the highest population (96 snails, 44.4%), followed by Antau Bridge (81 snails, 37.5%) and Mannu Bridge (39 snails, 18.1%). Five snail species were identified, with Melanoides spp dominating (173 snails, 80.1%), followed by Anisus spp (28 snails, 13.0%), Planorbarius spp (11 snails, 5.1%), Biomphalaria spp (3 snails, 1.4%), and Physa spp (1 snail, 0.5%). Biomphalaria spp, a known schistosomiasis vector, had a high cercarial shedding rate (66.7%) near Antau Bridge, signaling a potential risk for disease transmission. Physico-chemical analysis revealed favorable snail habitat conditions, with a mean water temperature of 28.0°C, pH of 7.0, and dissolved oxygen ranging from 6.58 mg/L to 6.75 mg/L. The study concludes that while the overall risk of schistosomiasis transmission may be low due to the small population of Biomphalaria spp, targeted vector control measures are necessary, particularly around Antau Bridge, to prevent further transmission of schistosomiasis. Key recommendations include regular monitoring of snail populations, public health education, and targeted mollusciciding to control the Biomphalaria spp population. The findings provide data for the development of control strategies aimed at reducing the burden of schistosomiasis in the region.

Exploring Botanical Innovations in Fish Aquaculture: A Review of Biological Impacts and Industry Prospects

Culture fisheries play a crucial role in providing protein-rich sustenance for the expanding global population. However, the intensification of fish farming comes with a downside – heightened stress among fish, which subsequently escalates the risk of disease transmission. The emergence of resilient bacterial populations and the accumulation of residues in body tissues due to the use of drugs and chemicals have underscored the necessity for the development of environmentally friendly and durable solutions. Notably, there has been a recent upsurge in interest regarding the use of botanical products to enhance aquaculture practices. Plant derived secondary metabolites have demonstrated their efficacy in stimulating appetite, facilitating growth, boosting immune responses, and exhibiting antibacterial as well as anti-parasitic properties within the realm of aquaculture. This article aims to comprehensively examine the body of research on the application of plant-derived products in pisciculture, elucidating their effects on various biological aspects of fish, including growth patterns, immune system functionality, pigmentation, blood composition, and reproductive parameters. Furthermore, the article also delivers inputs into an assessment of the current status of these practices, the methodologies deployed, and the challenges encountered in integrating plant-based solutions into the aquaculture industry.

Aedes aegypti surveillance under the International Health Regulations - experience at Madeira Island

Abstract Problem Aedes aegypti was first identified on Madeira Island in 2005, persisting since then. This mosquito transmits various haemorrhagic diseases and caused a Dengue outbreak in 2012-2013. The island has two seaports and one airport that may serve as points of entry or dissemination of these diseases, potentially leading to a new outbreak or international disease spread. We aimed to assess Ae. aegypti presence at the island’s seaports and airport during 2023. Description Data was collected from 52 entomological panels produced by the Regional Health Department throughout 2023. This data is publicly available on the Institute of Health Administration’s website. Ovitraps capture eggs, larvae, and pupae of Ae. aegypti, and BGtraps capture adult mosquitos. Positivity refers to the proportion of times an ovitrap recorded eggs in the entomological cycle. Results In 2023, there were 204 active ovitraps at the island (17 at the airport, 9 at Funchal’s seaport 8 at Caniçal’s seaport) and 24 BGtraps (2 at the airport, 2 at Funchal’s port and 1 at Caniçal’s port). Weekly reports revealed a median of 2243 (0-14448) eggs and 14 (0-234) mosquitos in all traps. Positivity was higher in the second semester. On average, ovitraps’ positivity at the airport (avg 6.4%; 0-59%) and at Caniçal’s port (avg 2.8%; 0-47%) were lower than the positivity of the island (avg 14.8%). Funchal’s port had a higher positivity than the island (avg 15.9%; 0-67%). Per-ovitrap, the average weekly positivity rate rose by 15%, 10% and 5% at Caniçal’s port, airport and Funchal’s port, respectively, compared to 2012-2022. Lessons Ae. aegypti’s eggs prevalence increased in 2023. The high positivity of eggs suggests an increased likelihood of mosquitos nearby. The detection of immature forms triggers actions to prospect the surrounding area for identification and elimination of breeding grounds, as well as the placement of salt in water accumulation areas. This is particularly important at high-traffic areas such as seaports and airports. Key messages • The increase in Ae. aegypti egg positivity in 2023 on Madeira Island suggests a higher risk of disease transmission. • It is essential to prioritize vector control measures at seaports and the airport in Madeira Island.

Sanitary Surveillance Program for pools in Matosinhos, Portugal

Abstract The use of pools for sports, recreational, and therapeutic activities has increased over time. It is important to ensure and control the quality of the water and surrounding areas, as well as the hygienic-sanitary conditions of these spaces. The ‘2018 Pool Sanitary Surveillance Program’ of the Portuguese Northern Regional Health Administration proposes the surveillance of water quality, teaching accessories, and surfaces. The aim of this investigation is to conduct microbiological analysis of the teaching accessories and surfaces in public pools in the municipality of Matosinhos and assess if this program has improved the results for water quality, teaching accessories, and surfaces from 2018 to 2023. The environmental health team of our Public Health Unit performed swabs of the teaching accessories and surfaces of all seven public pools in Matosinhos for microbiological analysis. The swabs were performed in 2018 (21), 2019 (48) and 2023 (42). During each visit, three random points were selected for analysis. In 2019, 31 rugs (64,6%) were analysed, but in 2023 only 10 (23,8%) were rugs. It was found that rugs had the highest contamination by P. aeruginosa (94,4%), fungi (60,8%), and the only sample with coagulase-positive Staphylococci. There was a decrease in samples from twelve to six with P. aeruginosa and an increase from 22 (46.8%) to 29 (69.0%) with fungi from 2019 to 2023. Bacterial colonies grew in 20 samples (95.2%) in 2018, 44 (91,6%) in 2019, and 42 (100%) in 2023. All water samples collected for the evaluation of microbiological parameters outlined obtained compliant results. Fungal and P. aeruginosa detection indicate a potential risk to the health of pool users. A quality report with corrective measures was produce for each pool in each visit. Surveillance of pool water, teaching materials and surrounding surfaces, is crucial to ensure water quality and safety. By doing so, we may lower the risk of disease transmission and protect the population’s health. Key messages • To ensure the safety of pool users is a public health challenge. It would be relevant to have legislation that addresses this issue. • To survey pools and its surroundings and accessories must be a continuous task, allied with literacy to management and users.

Combined performance of upper-room UVGI and ceiling-mounted air cleaners for removing active bioaerosol

Upper-room ultraviolet germicidal irradiation (UR-UVGI) and ceiling-mounted air cleaner (CM-AC) technologies contribute to curbing the spread of infectious diseases such as COVID-19. However, there is a lack of detailed studies on the performance differences between these two control technologies for reducing viral concentrations and infection risk in isolation ward environments with different ventilation modes, especially when used alone versus in combination. Therefore, this study performed numerical simulations under three ventilation modes, namely, downward ventilation (DWV), stratum ventilation (SV), and displacement ventilation (DV), by the Eulerian-Lagrangian method combined with the UV inactivation model. The viral disinfection performance of UR-UVGI and CM-AC was parametrically analyzed. The effectiveness of the combined application of these two control technologies in wards was evaluated. The results showed that expanding the irradiation range was more effective in enhancing the UR-UVGI performance with the same total UV flux. When using UR-UVGI only, DWV disinfected better at the same irradiation flux. In CM-AC cases, the viral aerosol removal efficiency was the greatest in DV. UR-UVGI and CM-AC had advantages in active bioaerosol removal in overall and localized indoor spaces, respectively. The combined application was recommended to maximize the air cleanliness. Under the role of UR-UVGI, a high level of disinfection could be achieved using CM-AC with low ventilation rates. When the CM-AC ventilation rate was 150 m3/h and the UV irradiance was 30 μW/cm2, the viral disinfection of DV exceeded 90 %, while that of DWV was also close to 90 %. The findings could provide insights to further lower the transmission risk of infectious diseases.

Bird Leg Skin Lesions and Urbanization in a Neotropical Savanna City.

Urban sprawl threatens biodiversity and is responsible for significant changes in the species that live in these environments. Given the high cost of comprehensive surveillance, monitoring disease indirectly, such as detecting skin lesions in birds, may help us better understand the prevalence of diseases affecting wild populations. We assessed the frequency of leg skin lesions, as a proxy of disease presence, in 1,565 individuals of 25 species, along the urban matrix of a large Neotropical city, Brasília, Federal District, Brazil. We tested the hypothesis that there is an increase in the frequency of skin lesions in birds due to urban intensification. We observed an increasing trend in some bird species between the frequency of occurrence of lesions and the intensity of urbanization. Species with a higher number of captures had an increase in the percentage of lesions, indicating that the occurrence of lesions may be linked to higher population density or that detection of the effect occurs only when sample sizes are high and controlled among urbanization categories. Our study highlights how the intensity of urbanization may increase the risk of disease transmission for these species. Unfortunately, studies on this topic are scarce in Neotropical regions, despite the region's high biodiversity and urban expansion.

A Recent Advance in the Diagnosis, Treatment, and Vaccine Development for Human Schistosomiasis.

Schistosomiasis, which affects a large number of people worldwide, is among the most overlooked parasitic diseases. The disease is mainly prevalent in sub-Saharan Africa, southeast Asian countries, and South America due to the lack of adequate sanitation. The disease is mainly associated with poor hygiene, sanitation, and contaminated water, so it is also known as a disease of poverty. Three Schistosoma species (S. mansoni, S. japonicum, and S. haematobium) cause significant human infections. Co-infections with Schistosoma and other parasites are widely common. All these parasites may cause intestinal or urogenital schistosomiasis, where the disease may be categorized into the acute, sensitized, and chronic phases. The disease is more prevalent among school children, which may cause anemia and reduce development. Chronic infections frequently cause significant liver, intestinal, and bladder damage. Women exposed to contaminated water while performing normal duties like washing clothes might acquire urogenital schistosomiasis (UGS), which can cause tissue damage and raise the risk of blood-borne disease transmission, including human immunodeficiency virus (HIV) transmission. Praziquantel (PZQ) is the World Health Organization (WHO)-prescribed treatment for individuals who are known to be infected, but it does not prevent further re-infections with larval worms. Vaccine development and new molecular-based diagnosis techniques have promised to be a reliable approach to the diagnosis and prevention of schistosomiasis. The current review emphasizes the recent advancement in the diagnosis of schistosomiasis by molecular techniques and the treatment of schistosomiasis by combined and alternative regimes of drugs. Moreover, this review has also focused on the recent outbreak of schistosomiasis, the development of vaccines, and their clinical trials.

A Dynamic System to Control the Entry of Non-Authorized Visitors and Detect Superspreader Farms in Strongly Interconnected Systems.

This study explores the critical challenges the livestock sector faces, particularly those related to biosecurity, animal welfare, and antibiotic use restrictions. It highlights the need to implement advanced information and communication technologies to enhance operational sustainability and decision-making. We introduce the Biorisk® External platform, a cloud-based visit control system designed to optimize biosecurity management by accurately tracking visitor activity through QR codes and GPS geolocation. During a 6-month study period from July to December 2023, we analyzed visits to 142 different swine production sites and 30 vehicle movement patterns. The analysis revealed trends in visitation patterns and compliance with biosecurity SOPs. The software categorized visits as authorized (A), not authorized with access (NAWA), and not authorized without access (NAWOA), providing a framework to assess biosecurity risks. Additionally, network analysis identified interconnected farms, which were classified as 'superspreaders', highlighting their considerable risk of disease transmission. This study advocates for the integration of digital systems in livestock operations to improve biosecurity measures, facilitate real-time data input, and support informed decision-making. By enhancing biosecurity protocols through technology, the livestock industry can better safeguard animal health, increase operational efficiency, and reduce potential economic losses associated with disease outbreaks.

From Proteomics to Diagnosis: Biomarker Discovery in Tuberculosis Research.

Tuberculosis (TB) is a leading cause of death from a single infectious disease worldwide. Early and accurate diagnosis is advantageous for timely detection and prompt treatment, thereby reducing the risk of disease transmission, which is essential for effective TB control. Biomarkers provide a valuable resource for TB diagnosis. Proteomic technologies have emerged as a powerful tool in biomarker discovery. In this perspective, we explore how proteomic technologies contribute to the discovery of TB diagnostic biomarkers. We also address the challenges and discuss prospective methods to augment the performance of biomarkers in diagnosing TB.

An overview of the challenges and methods for defining the wildlife-disease interface in the context of disease spread modelling, including concepts of infectious diseases epidemiology

ABSTRACT The wildlife-domestic interface is a key concept helping us to understand how diseases affect both wild and domestic animal populations, yet how to define and measure it remains a challenge. One tool which can contribute to our understanding of the wildlife-domestic interface is disease spread modelling. This can provide insight into how diseases spread within and between populations, and guide decision-making for disease control, response and surveillance programs. Specifically, quantitative estimation of contact rates permits such disease spread models to be developed and used confidently. Here we present a case study of the potential spread of rabies (an exotic disease in Australia) within the wild dog-domestic dog (Canis familiaris) ecosystem of northern Australia to illustrate the concept of the wildlife-domestic interface and disease transmission. We summarise a decade of research conducted to understand one such interface, the wild-domestic dog interface at one site in northern Australia, for the purposes of exploring the impact of one specific disease, rabies. Over a period of 10 years, free-roaming domestic dogs and wild dogs in the Northern Peninsula Area (NPA) of Cape York, Queensland were studied. Key findings included identification of a small but important group of domestic dogs which regularly roam in bushland areas; peri-urban wild dog activity, particularly in the dry season, likely driven by the availability of food sources; and the potential for interaction between hunting dogs and wild dogs in remote areas, particularly during the wet season. These observations can be used to inform disease spread models and identify strategies to mitigate the risks of disease transmission. However, the collection and incorporation of data into such models needs more consideration regarding what information is usable (such as contact rates) and the best ways to collect it. The scarcity of such models incorporating the wildlife-domestic interface suggests that integrated epidemiological-ecological studies are needed to fill this gap.