Virology Lectures 2023 #2: The Infectious Cycle

The complete course of events in a virus infected cell is called the infectious cycle. In this lecture we discuss the different phases of the infectious cycle and methods for studying it, including plaque assay, multiplicity of infection, and the particle-to-pfu ratio. Physical methods for detecting viruses include hemagglutination, serological techniques, polymerase chain reaction, and high-throughput sequencing. These methods were used to identify in early 2020 the pandemic coronavirus SARS-CoV-2.

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I’m Vincent Racaniello, Earth’s Virology Professor.

I’m also a professor of virology at Columbia University in New York. I’ve been doing research on viruses since 1976, and teaching virology in classrooms and online since 1999. On this YouTube channel I share videos of my lectures, podcasts, and more.

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#microbe #viruses #coronavirus #pandemic
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[Diagnoc]

I’m so excited that Dr Racaniello is starting the 2023 update of his excellent lectures on virology. And this time, I will be following these as soon as they appear on Youtube.

[NelsonRodrigoMartins]

I [Nelson] express my gratitude for the opportunity of updating in virology, despite at a distance (Brazil). I started attending your courses in 2020 during the COVID-19 pandemic. Thank you professor Racaniello.

[marklemont]

Thank you so much for sharing this wonderful information. The illustrations make it easier to understand.

[davidg.]

I've been watching these lectures since 2020 when the class went remote halfway through. Thank you for making this available. There is so much mis-information around the infectious cycle it is great to have one place to go.

[lmug]

Thanks so much for these courses! Great review from my studies of some virology years ago (and some new info, too!)

[Chris-pthh]

I was gonna take this course but seems I can learn it all without spending $6k and stressing over exams. Nice.

[dharmacharinipasadanandi]

This is absolutely brilliant. Thank you for the opportunity to study with you.

[Starclimber]

This is great! One thing, I single-framed through part of the plaque growth video, and it seems to be hours, not days, based on the second set of numbers advancing 10 through 50 and then the first number advancing by 1 when the second set hits 00.

[MRCAGR]

Thinking about the mRNA vaccine, are there cells that are resistant? Are there cells that are susceptible? Are there cells that are permissive? Are there cells that are susceptible and permissive? OR are all nucleated cells susceptible and permissive and hence the mRNA can enter all cells equally and replicate equally?

[janesa]

What if a cell type has two! receptors that the virus needs, like CD4 & CCR5 / CXCR4 with HIV? At 2:32 you speak of " a functional receptor", but sometimes as with HIV a functional receptor is not enough, it needs two. plural!

[tag_of_frank]

@58:27 Coronavirus phylogenetic tree what is the number 63? All of the others have high numbers above 80, but for 2019 wiv02-wiv07 we see 63. Is that the correlation between the viruses?

[mankwerabotho]

thank you. i saw a movie about henrietta.

[SharpSapphire]

@ 39:10, How do you do a plaque assay on celless viruses? What’s supposed to be visible?

[SharpSapphire]

Hemmagglutination possible for Type O ?

[patriciagiles]

If you take 0.1ml out of a10-6 dilution tube, how does it become a 10-7 dilution without placing it more solution? How does the concentration change by one log? Why am I confused?

[janqlan]

I am anxious about displaying my ignorance but here goes: I don't get 45 from e^-10. what am I doing wrong? I get 4.539E-5

[israelramos]

I ve never saw a cell culture in a Petri dish

[Rodrifuuu]

"Probable bat origin" they wrote, probably knowing already what the exact origin was.