Introduction to Virology and Viral Infections


This course deals with an introduction to virology and viral infections. It has the objective of guiding medical students to understand what a virus is and be able to list the components that combine to make one, knowing the key difference between replication of viruses and division of bacteria and the characteristics of viruses that are used to classify them. 


The resource also looks at the elements of the immune system, that is, controlling and eliminating virus infections and preventing virus infections...

Author(s): N. Cary EnglebergView Details of Author
Year: 2009
Keywords: virology, viral infections
Licensing Condition:

cc-by-nc© 2009, KNUST

Unless otherwise noted, the content of this programme is licensed under the terms of a Creative Commons Attribution-NonCommercial 3.0 Unported License.



Any medical information in this material is intended to inform and to educate and is not a tool for self-diagnosis or a replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional. You should speak to your physician or make an appointment to be seen if you have questions or concerns about this information or your medical condition.


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This is a narrated powerpoint presentation on the Introduction to Virology and Viral Infections prepared for 3rd-year medical students at the Kwame Nkrumah University of Science and Technology, Kumasi Ghana.




Students should use this material as a study guide to:

• Understand what a virus is and be able to list the components that combine to make one

• Know the key difference between replication of viruses and division of bacteria

• Know the characteristics of viruses that are used to classify them. How does the classification scheme work? (For this lecture, you do not need to memorize the characteristics of individuals viruses – but you will need to do this for each of the subject lectures that follow)

• Know how viruses are detected in patients and how they are quantified in clinical samples

• Know the steps in viral replication:

    1. Adsorption/adherence/entry (Know the two strategies) (Know how fusion proteins work)

    2. Production of viral proteins and replication of the viral genome (What steps do viruses with different nucleic acids have to follow in order to replicate their proteins and their genomes? More specifically, how do different classes of viruses differ in this respect) (Why is this important to know?)

    3. Assembly and release (Know the two strategies for getting out of the host cell)

• Understand the concept of tropism and why it occurs

• Understand the difference between an acute, chronic, and latent infection. Why is these important to distinguish?

• Be able to explain which elements of the immune system are important for:

    ‐‐ controlling and eliminating virus infections

    ‐‐ preventing virus infections

• Know what do some viruses do to avoid been eliminated by the immune system.

• Know what types of viral vaccines are there, and what types of immunity do they induce.


Lesson Content


Introduction: part 1 (Flash movie)


Introduction: part 2 (Flash movie)


Introduction: part 3 (Flash movie)


Introduction: part 4 (Flash movie)


Introduction: part 5 (Flash movie)




This programme was prepared by

N. Cary Engleberg, M.D.,

Department of Clinical Microbiology/SMS

KNUST, Kumasi, Ghana


This lecture was adapted from an original outline by:

Michael Imperiale, Ph.D.

Department of Microbiology & Immunology,

University of Michigan Medical School




This programme was produced with support from the following: