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Modeling Virus Dynamics in Time and Space
Published in Ranjit Kumar Upadhyay, Satteluri R. K. Iyengar, Spatial Dynamics and Pattern Formation in Biological Populations, 2021
Ranjit Kumar Upadhyay, Satteluri R. K. Iyengar
Influenza is a communicable acute respiratory disease and one of the major infectious disease threats to the human population. Influenza virus affects individuals of all ages, causes repeated infections throughout life, and is responsible for annual worldwide epidemics of varying severity, commonly referred to as seasonal influenza. Seasonal influenza epidemics offer unique opportunities to study the invasion and re-invasion waves of a pathogen in a partially immune population [47]. Due to a lack of suitable disease data, detailed patterns of the spread remain elusive. The underlying mechanisms dictating the spatial spread of seasonal influenza are not well understood, in part due to a lack of spatially resolved disease data to quantify patterns of spread. There are three types of influenza viruses that infect humans – A, B, and C – which are classified based on their immunological and biological properties. Influenza viruses are negative-strand RNA viruses with a segmented genome; influenza A and B viruses contain eight RNA segments, and influenza C contains seven RNA segments. Influenza A subtypes currently circulating among humans are influenza A (H1N1) and A (H3N2) [99,234]. Influenza causes severe illness and death in high-risk populations [211]. Influenza is a contagious disease, which broke out during 1918–1920 (Spanish flu), 1957–1958 (Asian flu), 1968–1969 (Hong Kong flu), 2002–2003 (SARS), and 2009–2010 (A/H1N1), which killed millions of people. Mathematical modeling of influenza was proposed from different points of view by various authors [217,233,240,258,283]. Viboud et al. [273] used influenza-related mortality data to analyze the between-state progression of inter-pandemic influenza in the United States over the past 30 years. A simple epidemiological model, based on the gravity formulation, captures the observed increase of influenza spatial synchrony with transmissibility; high transmission allows influenza to spread rapidly beyond local spatial constraints. Eifert et al. [81] used a variant of the logistic equation (as intrinsic growth) to describe a one-parameter discrete dynamical model for the spread of avian influenza. This model utilizes the Lindblad dissipation dynamics [92,164] for the biological rate equation.
Repurposing pharmaceutical excipients as an antiviral agent against SARS-CoV-2
Published in Journal of Biomaterials Science, Polymer Edition, 2022
Manisha Malani, Prerana Salunke, Shraddha Kulkarni, Gaurav K. Jain, Afsana Sheikh, Prashant Kesharwani, Jayabalan Nirmal
Effect of PVP-I on cell cultures infected by HIV and H5N1 virus was reported and found that PVP–I in 0.25% and 0.23% concentration was able to inactivate the respective virus [128]. Additionally, a study showed the effect of PVP-I in Madin-Darby canine kidney (MDCK) cells for the prevention of receptor mediated viral entry into the cell, inhibition of viral release, and spread of infected cells. It was found that 1.56 mg/ml of PVP-I was potent to inhibit infections of 8 human strains and 5 avian strains of influenza A virus including H1N1, H3N2, H5N3 and H9N2 [127]. Further, it presented the highest efficacy of 7.5% PVP-I when compared to 4% chlorhexidine gluconate and soft soap against Murine Norovirus in 15 healthy volunteers as per European Standard EN1499 (hygienic hand wash test method for bacteria) [129].
Influenza virus RNA recovered from droplets and droplet nuclei emitted by adults in an acute care setting
Published in Journal of Occupational and Environmental Hygiene, 2019
Lily Yip, Mairead Finn, Andrea Granados, Karren Prost, Allison McGeer, Jonathan B. Gubbay, James Scott, Samira Mubareka
Four and nine patient participants were infected with influenza A(H3N2) and influenza A(H1N1) viruses respectively; three participants were infected with influenza B virus. There was insufficient MT sample for quantification from one patient with influenza A(H1N1) virus and one patient with influenza B virus. The mean and median log10 copies/mL for MT swab viral load in patients with available samples was 4.08 (SD 2.39) and 4.13 (IQR 2.93–6.08) respectively. In patients with positive influenza A virus swabs, the mean and median log10 copies/mL for MT swab viral load were 4.71 (SD 2.21) and 4.83 (IQR 2.98–6.12). In patients with swabs positive for influenza A(H1N1) virus, the mean and median MT swab viral loads were 4.79 (SD 2.37) and 4.83 (IQR 3.85–6.12) log10 copies/mL. The mean and median MT swab viral load in patients with influenza A(H3N2) were identical at 4.32 (SD 1.97, IQR 2.93–5.71) log10 copies/mL. Finally, the mean and median MT swab viral load in patients with positive influenza B virus swabs was 1.78 (SD 1.60) and 2.24 (IQR 0–3.11) log10 copies/mL. There was no statistically significant difference between MT viral load and age, sex, number of symptoms, pharyngitis, need for oxygen, vaccination status, smoking status, or chest X-ray changes. However, there was a statistically significant association between higher viral load and fever (p-value 0.032).
Therapeutic potentials of endophytes for healthcare sustainability
Published in Egyptian Journal of Basic and Applied Sciences, 2021
Ayodeji O. Falade, Kayode E. Adewole, Temitope C. Ekundayo
On anti-influenza potentials of endophytic products, 6-O-demethyl-4-dehydroxyaltersolanol A (an hydroanthraquinone derivative) and other compounds isolated from the fermentation product of Nigrospora sp. YE3033, an endophytic fungus inhabiting Aconitum carmichaeli were reported to exhibit retarding effects on influenza viral strains including A/Puerto Rico/8/34 (H1N1), indicating the potential of these compounds as anti-influenza A virus agents [83]. Also, phomanolide (-)-6-methoxymellein, isolated from the fermentation culture of Phoma sp. from Aconitum vilmorinianum roots, has been reported to show antiviral activities against the same strain of influenza A virus [16]. Similarly, pestalols A, B, C, D, and E and other compounds purified from Pestalotiopsis sp. AcBC2, residing in Aegiceras corniculatum, exhibited inhibitory effects against Influenza A virus (H3N2) and Swine Flu (H1N1) [84]. Pullularin A from Pullularia sp. BCC 861 was reported to exhibit among other activities, anti-herpes simplex virus type-1 activity [62] while the extract of Chaetomium globosum JN711454 was reported to exhibit activity against herpes simplex virus type −2 [85]. Furthermore, the sesquiterpenoids, brasilamides B, C, and D, isolated from the fermentation broth of the endophytic fungus, Paraconiothyrium brasiliense Verkley inhibited ‘HIV-1 replication’ in C8166 cells [86]. Malformin A1, a peptide obtained from Aspergillus tubingensis FJBJ11, an endophytic fungus of Brucea javanica (L.), displayed effective inhibitory activity against the infection and multiplication of the tobacco mosaic virus, indicating the potentials of endophytic products as new viricide [46].