lecture recording on 24 February 2025 at 09.14.03 AM

Virus Life Cycles

• Lytic Cycle vs. Lysogenic Cycle

  • Similar to bacteriophages, viruses can reproduce through these two cycles.

  • Lysogenic cycle allows the virus to integrate into the host genome without causing immediate harm. This state is referred to as prophage.

CRISPR

• Emerging importance in genetics and virology; may begin appearing more frequently on exams in future.

Evolution of Viruses

• Evolution is often thought to lead to increased complexity.

• Interestingly, simplifications due to evolution, such as with certain species like starfish and tunicates, challenge this notion.

Retroviruses

• RNA viruses like the retrovirus can mutate rapidly, making vaccine development challenging. Specific mutation points are often elusive.

HIV Transmission

• Origin of HIV:

  • Initially mutated from a longstanding virus that affected big cats and then transitioned within different animal populations, ultimately leading to human infection.

  • Primarily spread through interactions involving capturing monkeys for food or trade.

Immune System and HIV

• HIV targets helper T cells, crucial for signaling other immune cells.

• Suppressor T cells may inhibit necessary immune responses, leading to increased susceptibility to diseases.

  • AIDS: Resulting from a progressively weakened immune system, allowing opportunistic infections to arise.

  • Some individuals remain asymptomatic for long periods despite HIV infection.

Vaccine Development

• The idea of tackling constant mutations in RNA viruses makes vaccine creation exceedingly difficult. Current approaches include multi-drug treatments.

• Examples of ongoing research include mRNA vaccines targeting various diseases.

HPV Vaccine

• Recommended for both males and females to reduce the risk of various cancers:

  • Initially targeted towards preventing genital warts and cervical cancer in women.

  • Recent findings link HPV to an increased risk of oral and pharyngeal cancers in men, prompting expanded recommendations.

Genetic Engineering and Ethics

• Discussions around genetic traits and eugenics.

  • Ethical dilemmas arise when considering genetic modifications to eliminate ethnic traits or enhance certain characteristics.

  • Importance of genetic diversity in populations is highlighted.

Historical and Cultural Insights

• Mention of how ancient beliefs and practices reflect a deep understanding of health, disease prevention, and community roles.

  • Example: Rituals surrounding menstruation in ancient cultures aligned with health and societal norms.