Students learn how viruses invade host cells and hijack the hosts' cell-reproduction mechanisms in order to make new viruses, which can in turn attack additional host cells. Students also learn how the immune system responds to a viral invasion, eventually defeating the viruses -- if all goes well. Finally, they consider the special case of HIV, in which the virus' host cell is a key component of the immune system itself, severely crippling it and ultimately leading to AIDS. The associated activity, Tracking a Virus, sets the stage for this lesson with a dramatic simulation that allows students to see for themselves how quickly a virus can spread through a population, and then challenges students to determine who the initial bearers of the virus were.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Hematopoietic stem cells (HSCs) are critical for maintaining healthy blood and immune cell populations. They’re also valuable resources and targets for medical treatments, such as HSC transplantation and gene therapy. However, these blood cell precursors are susceptible to viral infection, which can cause blood disorders and limit the efficacy of HSC-based therapies. In fact, viral infection is a leading cause of complications and death among HSC transplant recipients. For example, latent cytomegalovirus can become reactivated after transplantation leading to immunosuppression, pneumonia, encephalitis, and graft failure. HSC transplantation also reduces the numbers of T cells that are specifically cytotoxic toward the mononucleosis- inducing Epstein–Barr virus. Furthermore, recipients of HSC transplants are more susceptible to infection by SARS-CoV-2, the cause of the COVID-19 pandemic..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"HIV infection cannot yet be cured, but antiretroviral therapy (ART) dramatically slows disease progression and reduces the risk of transmission to others, including reducing transmission from mother to child during pregnancy. However, children exposed to, but not infected by, HIV in this way have increased risk of childhood infections, slowed growth, and increased mortality. To better understand the mechanism at play, a recent study examined the gut microbiota of over 250 infant-mother pairs in Nigeria. In the first six months of life, the relative abundance of Bifidobacterium species was lower in HIV-exposed infants. Among HIV-exposed infants, breastfeeding was beneficial to their growth rate but did not correspond to a higher abundance of Bifidobacterium. In fact, the presence of ART drug metabolites in breastmilk was associated with reduced relative abundance of Bifidobacterium species..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.