Virology
Where Did HIV Come From?
By Gertrud U. Rey
by Gertrud U. Rey As discussed in my previous post, we first became aware of human immunodeficiency virus (HIV) in the early 1980s. However, when did the virus actually emerge in humans, and where did it come from? Photo of a chimpanzee by Andrius Ordojan There are two strains of ...
Why Don’t We Have an HIV Vaccine?
By Gertrud U. Rey
by Gertrud U. Rey This post was written in honor of Virus Appreciation Day, which occurs annually on October 3. Public awareness of human immunodeficiency virus (HIV) began in the early 1980s when separate clusters of infected individuals were identified in Los Angeles, San Francisco, and New York. These individuals ...
Sloth Fever
By Gertrud U. Rey
by Gertrud U. Rey Recent news headlines have featured a mysterious and presumably new illness termed “sloth fever.” More aptly named Oropouche fever, the disease is caused by Oropouche virus (OROV), an arthropod-borne virus that is transmitted primarily through the biting midge Culicoides paraensis. OROV typically circulates in sloths, non-human ...
Why Does Stress Reactivate Herpes Simplex?
By Gertrud U. Rey
by Gertrud U. Rey It is well known that stress and exposure to UV radiation can reactivate replication of latent herpes simplex virus type 1 and/or type 2 (HSV-1 and/or HSV-2), and the painful lesions associated with these infections. But why is that? During a primary infection, HSV-1 and HSV-2 ...
Active vs. Passive Immunity
By Gertrud U. Rey
by Gertrud U. Rey During the first few months of life, residual maternal antibodies that crossed the placenta during gestation and antibodies from breast milk protect infants from infection with various microbes. This type of immune protection is known as “passive immunity,” and differs from “active immunity,” which develops in ...