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Exposure to nanoplastics affects the outcome of infectious disease in phytoplankton
2021
Schampera, Charlotte | Wolinska, Justyna | Bachelier, Julien B. | de Souza Machado, Anderson Abel | Rossal S., J. Roberto (Julio Roberto Rossal Salazar) | González-Pleiter, Miguel | Agha, Ramsy
Infectious diseases of humans and wildlife are increasing globally but the contribution of novel artificial anthropogenic entities such as nano-sized plastics to disease dynamics remains unknown. Despite mounting evidence for the adverse effects of nanoplastics (NPs) on single organisms, it is unclear whether and how they affect the interaction between species and thereby lead to ecological harm. In order to incorporate the impact of NP pollution into host-parasite-environment interactions captured in the “disease triangle”, we evaluated disease outcomes in the presence of polystyrene NP using an ecologically-relevant host-parasite system consisting of a common planktonic cyanobacterium and its fungal parasite. NP at high concentrations formed hetero-aggregates with phytoplankton and inhibited their growth. This coincided with a significant reduction in infection prevalence, highlighting the close interdependency of host and parasite fitness. Lower intensity of infection in the presence of NP indicates that reduced disease transmission results from the parasite’s diminished ability to establish new infections as NP formed aggregates around phytoplankton cells. We propose that NP aggregation on the host’s surface acts as a physical barrier to infection and, by reducing host light harvesting, may also hamper parasite chemotaxis. These results demonstrate that the consequences of NP pollution go well beyond toxic effects at the individual level and modulate the intensity of species interactions, thereby potentially eliciting diverse cascading effects on ecosystem functioning.
Afficher plus [+] Moins [-]Mask use during COVID-19: A risk adjusted strategy
2020
Wang, Jiao | Pan, Lijun | Tang, Song | Ji, John S. | Shi, Xiaoming
In the context of Coronavirus Disease (2019) (COVID-19) cases globally, there is a lack of consensus across cultures on whether wearing face masks is an effective physical intervention against disease transmission. This study 1) illustrates transmission routes of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2); 2) addresses controversies surrounding the mask from perspectives of attitude, effectiveness, and necessity of wearing the mask with evidence that the use of mask would effectively interrupt the transmission of infectious diseases in both hospital settings and community settings; and 3) provides suggestion that the public should wear the mask during COVID-19 pandemic according to local context. To achieve this goal, government should establish a risk adjusted strategy of mask use to scientifically publicize the use of masks, guarantee sufficient supply of masks, and cooperate for reducing health resources inequities.
Afficher plus [+] Moins [-]Inactivation of ova of the parasites Taenia saginata and Ascaris suum during heated anaerobic digestion
1983
Pike, E.B. | Morris, D.L. | Carrington, E.G.
Taenia saginata, Ascaris suum, current research on inactivation of ova in sewage sludge by means of heated anaerobic digestion: United Kingdom
Afficher plus [+] Moins [-]Seasonal variation of bacterial communities in shellfish harvesting waters: Preliminary study before applying phage therapy
2015
Pereira, C. | Santos, L. | Silva, A.P. | Silva, Y.J. | Cunha, A. | Romalde, J.L. | Nunes, M.L. | Almeida, A.
The recurrent emergence of infections outbreaks associated with shellfish consumption is an important health problem, which results in substantial economic losses to the seafood industry. Even after depuration, shellfish is still involved in outbreaks caused by pathogenic bacteria, which increases the demand for new efficient strategies to control the shellfish infection transmission. Phage therapy during the shellfish depuration is a promising approach, but its success depends on a detailed understanding of the dynamics of bacterial communities in the harvesting waters. This study intends to evaluate the seasonal dynamics of the overall bacterial communities, disease-causing bacterial populations and bacterial sanitary quality indicators in two authorized harvesting-zones at Ria de Aveiro.During the hot season, the total bacterial community presented high complexity and new prevalent populations of the main shellfish pathogenic bacteria emerged. These results indicate that the spring/summer season is a critical period during which phage therapy should be applied.
Afficher plus [+] Moins [-]The destruction of pathogens and parasites in sewage sludge by chemical means
1983
Godfree, A.F. | Bevins, R. | Jones, F.
Taenia saginata and other pathogens likely to cause problems resulting from agricultural use of sewage sludge, laboratory and field trials testing efficacy of DF 955 (formalin based compound) as a means of chemical destruction
Afficher plus [+] Moins [-]The impact of mucormycosis (black fungus) on SARS-CoV-2-infected patients: at a glance
2022
Islam, Md Rezaul | Rahman, Md Mominur | Ahasan, Md Tanjimul | Sarkar, Nadia | Akash, Shopnil | Islam, Mahfuzul | Islam, Fahadul | Aktar, Most Nazmin | Saeed, Mohd | Hāruna-ara-Raśīda, Moḥ. | Hosain, Md Kawsar | Rahaman, Md Saidur | Afroz, Sadia | Bibi, Shabana | Md. Habibur Rahman, | Sweilam, Sherouk Hussein
The emergence of various diseases during the COVID-19 pandemic made health workers more attentive, and one of the new pathogens is the black fungus (mucormycosis). As a result, millions of lives have already been lost. As a result of the mutation, the virus is constantly changing its traits, including the rate of disease transmission, virulence, pathogenesis, and clinical signs. A recent analysis revealed that some COVID-19 patients were also coinfected with a fungal disease called mucormycosis (black fungus). India has already categorized the COVID-19 patient black fungus outbreak as an epidemic. Only a few reports are observed in other countries. The immune system is weakened by COVID-19 medication, rendering it more prone to illnesses like black fungus (mucormycosis). COVID-19, which is caused by a B.1.617 strain of the SARS-CoV-2 virus, has been circulating in India since April 2021. Mucormycosis is a rare fungal infection induced by exposure to a fungus called mucormycete. The most typically implicated genera are Mucor rhyzuprhizopusdia and Cunninghamella. Mucormycosis is also known as zygomycosis. The main causes of infection are soil, dumping sites, ancient building walls, and other sources of infection (reservoir words “mucormycosis” and “zygomycosis” are occasionally interchanged). Zygomycota, on the other hand, has been identified as polyphyletic and is not currently included in fungal classification systems; also, zygomycosis includes Entomophthorales, but mucormycosis does not. This current review will be focused on the etiology and virulence factors of COVID-19/mucormycosis coinfections in COVID-19-associated mucormycosis patients, as well as their prevalence, diagnosis, and treatment.
Afficher plus [+] Moins [-]Hand hygiene with hand sanitizer versus handwashing: what are the planetary health consequences?
2022
Duane, Brett | Pilling, Jessica | Saget, Sophie | Ashley, Paul | Pinhas, Allan R. | Lyne, Alexandra
In order to reduce the transmission of pathogens, and COVID-19, WHO and NHS England recommend hand washing (HW) and/or the use of hand sanitizer (HS). The planetary health consequences of these different methods of hand hygiene have not been quantified. A comparative life cycle assessment (LCA) was carried out to compare the environmental impact of the UK population practising increased levels of hand hygiene during the COVID-19 pandemic for 1 year. Washing hands with soap and water was compared to using hand sanitizer (both ethanol and isopropanol based sanitizers were studied). The isopropanol-based HS had the lowest environmental impact in 14 out of the 16 impact categories used in this study. For climate change, hand hygiene using isopropanol HS produced the equivalent of 1060 million kg CO₂, compared to 1460 million for ethanol HS, 2300 million for bar soap HW, and 4240 million for liquid soap HW. For both the ethanol and isopropanol HS, the active ingredient was the greatest overall contributing factor to the environmental impact (83.24% and 68.68% respectively). For HW with liquid soap and bar soap, there were additional contributing factors other than the soap itself: for example tap water use (28.12% and 48.68% respectively) and the laundering of a hand towel to dry the hands (10.17% and 17.92% respectively). All forms of hand hygiene have an environmental cost, and this needs to be weighed up against the health benefits of preventing disease transmission. When comparing hand sanitizers to handwashing with soap and water, this study found that using isopropanol based hand sanitizer is better for planetary health. However, no method of hand hygiene was ideal; isopropanol had a greater fossil fuel resource use than ethanol based hand sanitizer. More research is needed to find hand hygiene sources which do not diminish planetary health, and environmental impact is a consideration for public health campaigns around hand hygiene.
Afficher plus [+] Moins [-]Modelling affected regions by the Iberian Quercus disease with proximity diagrams
2021
Calvo-Jurado, Carmen
In this work, we propose a mathematical model to determine the potential propagation areas of the Mediterranean Quercus disease commonly referred to as “seca” (Tuser and Sánchez 2004) in specific areas of Extremadura. Although it is a syndrome of complex etiology caused by the action of the different biotic (insects and fungi) and abiotic factors (temperature, orography, soil, etc.), numerous studies suggest that the soil-borne pathogen cinnamomi represents the main responsible for the decay of the holm and cork oak. However, very little is known about the Phytophthora epidemic distribution patterns and its geographical dependence on other factors that favor its spread. With the aim to clarify this question, in this paper, we will use optimal computational geometry algorithms based on proximity diagrams that allow us to design a pathogen transmission map and to determine its correlation with different causing agents, specially with the presence of standing water or drainage lines water.
Afficher plus [+] Moins [-]The impact of coronavirus SARS-CoV-2 (COVID-19) in water: potential risks
2021
Girón-Navarro, Rocío | Linares-Hernández, Ivonne | Castillo-Suárez, Luis Antonio
This review summarizes research data on SARS-CoV-2 in water environments. A literature survey was conducted using the electronic databases Science Direct, Scopus, and Springer. This complete research included and discussed relevant studies that involve the (1) introduction, (2) definition and features of coronavirus, (2.1) structure and classification, (3) effects on public health, (4) transmission, (5) detection methods, (6) impact of COVID-19 on the water sector (drinking water, cycle water, surface water, wastewater), (6.5) wastewater treatment, and (7) future trends. The results show contamination of clean water sources, and community drinking water is vulnerable. Additionally, there is evidence that sputum, feces, and urine contain SARS-CoV-2, which can maintain its viability in sewage and the urban-rural water cycle to move towards seawater or freshwater; thus, the risk associated with contracting COVID-19 from contact with untreated water or inadequately treated wastewater is high. Moreover, viral loads have been detected in surface water, although the risk is lower for countries that efficiently treat their wastewater. Further investigation is immediately required to determine the persistence and mobility of SARS-CoV-2 in polluted water and sewage as well as the possible potential of disease transmission via drinking water. Conventional wastewater treatment systems have been shown to be effective in removing the virus, which plays an important role in pandemic control. Monitoring of this virus in water is extremely important as it can provide information on the prevalence and distribution of the COVID-19 pandemic in different communities as well as possible infection dynamics to prevent future outbreaks.
Afficher plus [+] Moins [-]Interaction between meteorological parameters and COVID-19: an ecological study on 406 authorities of the UK
2021
Sarmadi, Mohammad | Rahimi, Sajjad | Evensen, Darrick | Kazemi Moghaddam, Vahid
Understanding the factors affecting COVID-19 transmission is critical in assessing and mitigating the spread of the pandemic. This study investigated the transmissibility and death distribution of COVID-19 and its association with meteorological parameters to study the propagation pattern of COVID-19 in UK regions. We used the reported case and death per capita rate (as of November 13, 2020; before mass vaccination) and long-term meteorological data (temperature, humidity, precipitation, wind speed, and visibility) in 406 UK local authority levels based on publicity available secondary data. We performed correlation and regression analysis between COVID-19 variables and meteorological parameters to find the association between COVID-19 and independent variables. Student’s T and Mann–Whitney’s tests were used to analyze data. The correlation and regression analyses revealed that temperature, dew point, wind speed, and humidity were the most important factors associated with spread and death of COVID-19 (P <0.05). COVID-19 cases negatively correlated with humidity in areas with high population density, but the inverse in low population density areas. Wind speeds in low visibility areas, which are considered polluted air, may increase the spread of disease (r=0.42, P <0.05) and decrease the spread in high visibility areas (r=−0.16, P <0.05). Among low (T <10°C) and high (T >10°C) temperature areas, the average incidence rates were 2056.86 (95% confidence interval (CI): 1909.49–2204.23) and 1446.76 (95% CI: 1296.71–1596.81). Also, COVID-19 death per capita rates were 81.55 (95% CI: 77.40–85.70) and 69.78 (95% CI: 64.39–75.16) respectively. According to the comprehensive analysis, the spread of disease will be suppressed as the weather warms and humidity and wind speed decrease. Different environmental conditions can increase or decrease spread of the disease due to affecting spread of disease vectors and by altering people’s behavior.
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