SEIAS-SEI model on asymptomatic and super infection malaria with imperfect vaccination

AbstractRecent developments on extracellular vesicles (EVs) containing multiple virus particles challenge the rigid definition of non-enveloped viruses. However, how non-enveloped viruses hijack cell machinery to promote non-lytic release in EVs, and their functional roles, remain to be clarified. Here we used Bluetongue virus (BTV) as a model of a non-enveloped arthropod-borne virus and observed that the majority of viruses are released in EVs, both in vitro and in the blood of infected animals. Based on the cellular proteins detected in these EVs, and use of inhibitors targeting the cellular degradation process, we demonstrated that these extracellular vesicles are derived from secretory lysosomes, in which the acidic pH is neutralized upon the infection. Moreover, we report that secreted EVs are more efficient than free-viruses for initiating infections, but that they trigger super-infection exclusion that only free-viruses can overcome.Author summaryRecent discoveries of non-enveloped virus secreted in EVs opened the door to new developments in our understanding of the transmission and pathogenicity of these viruses. In particular, how these viruses hijack the host cellular secretion machinery, and the role of these EVs compared with free-virus particles remained to be explored. Here, we tackled these two aspects, by studying BTV, an emerging arthropod-borne virus causing epidemics worldwide. We showed that this virus is mainly released in EVs, in vivo and in the blood of infected animals, and that inhibition of the cell degradation machinery decreases the release of infectious EVs, but not free-virus particles. We found that BTV must neutralize the pH of lysosomes, which are important organelles of the cell degradation machinery, for efficient virus release in EVs. Our results highlight unique features for a virus released in EVs, explaining how BTV transits in lysosomes without being degraded. Interestingly, we observed that EVs are more infectious than free-virus particles, but only free-viruses are able to overcome the super-infection exclusion, which is a common cellular defense mechanism. In conclusion, our study stresses the dual role played by both forms, free and vesicular, in the virus life cycle.

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Mucormycosis in CAPA, a Possible Fungal Super-Infection

Journal of Fungi ◽

10.3390/jof7090708 ◽

2021 ◽

Vol 7 (9) ◽

pp. 708

Author(s):

Paola Saltini ◽

Emanuele Palomba ◽

Valeria Castelli ◽

Marco Fava ◽

Laura Alagna ◽

...

Keyword(s):

Pulmonary Infection ◽

Morbidity And Mortality ◽

Significant Morbidity ◽

Pulmonary Aspergillosis ◽

First Case ◽

Super Infection

The occurrence of pulmonary fungal superinfection due to Aspergillus spp. in patients with COVID-19 is a well-described complication associated with significant morbidity and mortality. This can be related to a directed effect of the virus and to the immunosuppressive role of the therapies administered for the disease. Here, we describe the first case of pulmonary infection due to Mucorales occurring in a patient with a concomitant diagnosis of COVID-19-associated pulmonary aspergillosis.

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APLIKASI MODEL EPIDEMIK SEIAR-SEI PADA PENYEBARAN PENYAKIT MALARIA DENGAN INFEKSI ASIMTOMATIK DAN SUPER INFEKSI

Jurnal Matematika Statistika dan Komputasi ◽

10.20956/jmsk.v15i2.5715 ◽

2018 ◽

Vol 15 (2) ◽

pp. 67

Author(s):

Stella Maryana Belwawin

Keyword(s):

Equilibrium Point ◽

Basic Reproduction Number ◽

Reproduction Number ◽

Asymptomatic Infection ◽

Endemic Equilibrium ◽

Asymptomatic Infections ◽

The Stability ◽

Super Infection ◽

The Basic Reproduction Number

AbstractThis aim of this study is to determine the point of equilibrium and analyze the stability of SEIAR-SEI model on malaria disease with asymptomatic infection, super infection and the effect of the mosquito's life cycle. This study also aim is to measure the sensitivity of the spread of malaria to the parameters of asymptomatic infections, the rate of treatment, and the rate of birth of mosquitoes through the magnitude of . The method in this research is deductively, through several stage, such as determination of disease-free equilibrium point and endemic equilibrium point, determination of basic reproduction number (), analyze of the basic reproduction number sensitivity of the spread of malaria to the parameters of asymptomatic infections, the rate of treatment, and the rate of birth of mosquitoes. The endemic equilibrium point was obtained using rule of Descartes. The result show that the change in the value of parameter , , and has effect on the basic reproduction number (). Treatment factors in the human population influence the elimination of malaria in a population. Whereas asymptomatic infection factors and the birth rate of adult mosquitoes influence the increase in malaria infection. Keywords: Malaria, asymptomatic infection, super infection, basic reproduction number, rule of descrates. AbstrakPenelitian ini bertujuan menentukan titik keseimbangan dan menganalisis kestabilan dari model SEIAR_SEI pada penyakit malaria dengan pengaruh infeksi asimtomatik, super infeksi, dan siklus hidup nyamuk. Penelitian ini juga bertujuan mengukur tingkat sensitivitas penyebaran penyakit malaria terhadap parameter infeksi asimtomatik, laju pengobatan, serta laju kelahiran nyamuk.melalu besaran . Metode yang digunakan dalam penelitian ini adalah metode deduktif dengan langkah-langkah : menentukan titik keseimbangan bebas penyakit dan endemik dan menentukan bilangan reproduksi dasar ). Analisis sensitivitas bilangan reproduksi dasar dilakukan terhadap parameter infeksi asimtomatik, pengobatan, dan laju kelahiran nyamuk. Tititk keseimbangan endemik diperoleh dengan aturan descrates. Hasil yang diperoleh menunjukkan parameter , , dan berpengaruh terhadap bilangan reproduksi dasar (). Faktor pengobatan berpengaruh terhadap eliminasi penyakit malaria. Sedangkan faktor infeksi asimtomatik dan laju kelahiran nyamuk dewasa berpengaruh terhadap peningkatan infeksi penyakit malaria. Kata kunci: Malaria, Infeksi Asimtomatik, Super Infeksi, Bilangan Reproduksi Dasar, Aturan Descrates .

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