Study of Virology

Explore viral structure: enveloped versus nonenveloped viruses, the nucleocapsid protecting DNA or RNA, and capsomere-based, icosahedral, helical, or complex symmetry.

Outer viral proteins mediate attachment to specific receptors, aided by the envelope and capsid, while internal proteins include structural capsid components and enzymes like RNA-dependent RNA polymerase and reverse transcriptase.

Trace the viral replication cycle from adsorption and penetration to uncoating, synthesis, assembly, and release, highlighting fusion and endocytosis across enveloped and non-enveloped viruses, using Adenovirus as an example.

Explain how viruses multiply inside living cells, some entering a latent period with low viral load and no symptoms, and show how latent period length influences severity.

Demonstrate how a lytic infection begins when a bacteriophage injects DNA into a bacterial cell, hijacks machinery, and lyses the cell to release virions and viremia.

Explore lysogenic infections, where viral dna inserts into the host bacterial dna as a prophage, replicated with the host for generations. Trigger environmental factors to activate the lytic cycle.

Explain the Baltimore classification, a virus grouping by genome type and replication, detailing dsDNA, dsDNA with RNA intermediate, ssDNA, dsRNA, positive- and negative-sense RNA, and RNA with DNA intermediates.

The central dogma describes DNA replication, transcription into RNA, and translation into protein, driving most cellular work. Reverse transcriptase reverses this flow in retroviruses, creating DNA from RNA.

Describe how viruses transcribe genomes and translate envelope and capsid proteins to multiply and spread infection, and how positive versus negative sense RNA, operons, and transcription factors regulate expression.

Transcriptases in virology explain how viruses transcribe genomes, using host RNA polymerase II in the nucleus or viral enzymes in the cytoplasm, with reverse transcriptase in retroviruses.

Transport viral mRNA from the nucleus to the cytoplasm and translate at the rough endoplasmic reticulum. Track how viral proteins move to the Golgi and plasma membrane to assemble virions.

Study prions as infectious proteins that misfold from prpc to prpsc, spreading neurodegenerative diseases such as mad cow disease, scrapie, and rival Jacob syndrome, while discussing pathogenesis, transmission, and prevention.

Explore how virus life cycle steps shape pathogenesis, from entry and tissue tropism to dissemination, viremia, and shedding, and how innate immunity and tropism modulate infection.

Viral tropism dictates replication sites by binding viral surface proteins to cell receptors, shaping pathogenesis and virulence. Host factors such as genetics, age, and immunocompetence modulate infection outcomes.

Explore how viral infections replicate in host cells and cause disease through multiplication. Identify viruses as obligate intracellular parasites relying on host ribosomes and note carriers, vectors, and asymptomatic cases.

Viruses enter host cells, replicate their genome, translate proteins, and assemble virions, causing host cell death; the host immune response can cause immunopathology through cytokines and interferons.

Describe acute, persistent, latent, and slow viral infections, with patterns of viral load over time, and show how innate and adaptive immunity drives clearance or control.

Explore how common human viruses persist in sites like B cells, liver, or sensory ganglia, causing cancers or AIDS, and examine latency and reactivation in HSV.

Explore how the host immune system, including innate and adaptive defenses, recognizes and combats viral infections, and how viral evasion leads to tissue injury, necrosis, or apoptosis.

analyze innate and adaptive immune responses to viral infections, highlighting interferons, NK cells, humoral and cell-mediated immunity, and antibody dependent cell mediated cytotoxicity.

Host defenses against viral infections start with physical and chemical barriers, then innate responses with cytokines and inflammation, and finally adaptive immunity via antibodies, cytotoxic T cells, and memory.

Show how intrinsic defense integrates with the innate and adaptive immune response to protect against viral infection, via dendritic cells, natural killer cells, cytokines, and memory B and T lymphocytes.

Apoptosis, as programmed cell death, shapes the antiviral response by forming apoptotic bodies that macrophages phagocytose, while viruses regulate this process via BCL-2, caspases, and p53.

Define viral tropism as the binding and fusion of viral envelope proteins with host cells, shaping the host range, with receptor dependent or independent entry guiding transmission, replication, and pathogenesis.

Explore HIV receptors and tropism, including CD4+ T helper cells and co-receptors, and how HIV infects macrophages and dendritic cells, with transmission routes, prevention, and treatment strategies.

Outline the coronavirus family, including SARS and SARS-CoV-2, describe fever, cough, and pneumonia, and explain transmission via droplets and surfaces with prevention by hand hygiene, masks, and disinfection.

Explore CMV epidemiology, transmission routes from infancy through perinatal periods, and congenital CMV manifestations such as microcephaly, chorioretinitis, and hepatosplenomegaly, including HIV co-infection risks.

Explore hepatitis B epidemiology, transmission from perinatal and household contact, chronic infection criteria (HBsAg more than six months), risk factors, vaccination, clinical manifestations, and host–virus immune interactions.