In animals, exogenous retroviruses are responsible for some of the deadliest diseases known.
Yet, it wasn’t until 1980 when Poiesz and Ruscetti isolated the first human disease-causing
retrovirus, then called Human T-cell Leukemia Virus as it was shown to cause an aggressive cancer called
Adult T-cell leukemia (ATL).
In fact, when my mentor and colleague of 35 years, Frank Ruscetti, joined the National Cancer
Institute (NCI) in 1975 to study human disease causing exogenous retroviruses, he was told by NCI
scientist John M. Coffin not to bother as they did not exist.
Although retroviruses have been an important part of human evolution as the placenta evolved
from ancestral retroviral envelope genes 25-40 million years ago, envelope genes from both exogenous and
endogenous retroviruses, aberrantly expressed in humans, have been shown to be responsible for the
development of many chronic diseases.
The incidence rates of these diseases are skyrocketing in 21st century America and include
prostate cancer, breast cancer, leukemia lymphoma, multiple sclerosis, and amyotropic lateral sclerosis
(Lou Gherig’s disease).
Expression and mode of development
Many factors are important in the development of diseases associated with retroviruses. The
expression and mode of transmission are keys to disease development.
We have learned a great deal about the types of diseases from 40 years of study of the
mechanisms of disease development from animal and human retroviruses.
The two main modes of retrovirus transmission are shown schematically below:
In mitotic transmission, the provirus is dormant or defective and the integrated proviral form
of exogenous retroviruses (gag-, pol-, and env-related regions flanked by 2 LTRs) are not expressed.
In this case only the daughter cells carry the retroviral genes and if not expressed these
endogenous or exogenous retroviral genes remain dormant for years and do not usually contribute to
disease until much later in life as the immune system weakens.
During infectious transmission, the complete virion is produced with many thousands of virions
infecting many neighboring cells and spreading from person to person -- both cell free and cell
associated -- via blood and body fluids.
Infectious transmission of HIV drove the AIDS epidemic of the 80s and 90s including transmission
from infected cells in a contaminated blood supply and the activation of dormant retroviruses by heavy
metals, co-infections and inappropriate vaccination of HIV infected individuals.
Xenograft approaches commonly used since the 1950s in studies of human cancer, autoimmune, and
neuroimmune disease promote the evolution of novel retroviruses with pathogenic properties. We now
appreciate that it is the use of xenograft technologies in the development of vaccines and biological
drugs and genetically modified organisms (GMOs) that have accelerated the spread of animal retroviruses
into humans, a process known as zoonosis, whereby an animal retrovirus jumps species, learning to evade
immune mechanisms of humans and thereby causing disease.
The rotavirus vaccine
Looking at the excipient list of vaccines, we can quickly see that every vaccine may be contaminated
with at least one animal retrovirus family, all of which have been associated with cancers, chronic
liver disease, AIDS, ALS, ME/CFS and autism.
As just one example among hundreds of retrovirus contamination of vaccines, take a look at the history
of the rotavirus vaccine. In 2010, the Food and Drug Administration (FDA) convened a panel of experts to
review findings that rotavirus vaccines given to infants in the U.S., Rotateq, produced by Merck
Pharmaceuticals and Rotarix produced by Glaxo Smith Kline, are contaminated with pig viruses.
Rotarix, an orally administered rotavirus vaccine, contained nucleic acids from porcine
circovirus-1 (PCV1) virus and RotaTeq has been shown to contain nucleic acids from both PCV1 and PCV2, a
pathogen in pigs that is associated with wasting and immunodeficiency.
While acknowledging that the entire short and long-term risks from the porcine circoviruses PCV1
and PCV2 are as yet unknown, the advisory panel decided that: “the benefits of the vaccine trumps its
While the technology to detect genetic contaminates in vaccines was not available until
relatively recently, the dangers of generating new viruses and bacteria that can cause diseases were
foreseen by the pioneers of genetic engineering.
To be continued