americanthinker | The public has been misinformed regarding human-to-human transmission of Ebola.
Assurances that Ebola can be transmitted only through direct contact
with bodily fluids need to be seriously scrutinized in the wake of the
West Africa outbreak.
The Canadian Health Department states that airborne transmission of Ebola is strongly suspected and the CDC admits that
Ebola can be transmitted in situations where there is no physical
contact between people, i.e.: via direct airborne inhalation into the
lungs or into the eyes, or via contact with airborne fomites which adhere to nearby surfaces. That helps explain why 81 doctors, nurses
and other healthcare workers have died in West Africa to date. These
courageous healthcare providers use careful CDC-level barrier
precautions such as gowns, gloves, and head cover, but it appears they
have inadequate respiratory and eye protection. Dr. Michael V. Callahan,
an infectious disease specialist at Massachusetts General Hospital who
has worked in Africa during Ebola outbreaks said that minimum CDC level
precautions
“led to the infection of my nurses and physician co-workers who came in contact with body fluids.”
Currently the CDC advises healthcare workers to use goggles and simple face masks for respiratory and eye protection, and a fitted N-95 mask during
aerosol-generating medical procedures. Since so many doctors and nurses
are dying in West Africa, it is clear that this level of protection is
inadequate. Full face respirators with P-100 (HEPA) replacement filters would
provide greater airway and eye protection, and I believe this would
save the lives of many doctors, nurses, and others who come into close
contact with, or in proximity to, Ebola victims.
The
United States Army Medical Research Institute of Infectious Diseases
conducted a monkey to monkey Ebola study in December 1995, published in The Lancet, Vol. 346. (Here is a link to the abstract,
but the entire article must be purchased.) Several Rhesus monkeys were
infected with Zaire Ebola by intramuscular injection while three control
Rhesus monkeys were kept in cages separated 10 feet from the infected
monkeys. All of the injected monkeys died of Ebola by day 13 and 2 out
of 3 control monkeys died of Ebola by 8 days after that. The authors of
this study concluded that:
"The exact mode of transmission to the control monkeys cannot be absolutely determined, although the pattern of pulmonary antigen staining in one of the control monkeys was virtually identical to that reported in experimental Ebola virus aerosol infection in rhesus monkeys, suggesting airborne transmission of the disease via infectious droplets... Fomite or contact droplet transmission of the virus between cages was considered unlikely. Standard procedures in our BL4 containment laboratories have always been successful in the prevention of transmission of Ebola or Marburg virus to uninflected animals. Thus, pulmonary, nasopharyngeal, oral, or conjunctival exposure to airborne droplets of the virus had to be considered as the most likely mode of infection... Our present findings emphasize the advisability of at-risk personnel employing precautions to safeguard against ocular, oral, and nasopharyngeal exposure to the virus."
Another NHP to NHP (monkey-to-monkey)
study was published in July of this year. Rhesus monkeys were infected
with Ebola via intramuscular injection and they were terminated on day 6
after becoming unresponsive, but without developing vomiting, diarrhea,
or apparent respiratory illness. Ebola virus was detected in their
blood, and genetic fragments of Ebola were found in their nose, mouth,
and rectum, but no intact infectious Ebola virus was found.
Control
Cynomolgus monkeys were caged 1 foot away from the infected Rhesus
monkeys but did not become infected with Ebola. This experiment is not a
helpful comparison in human to human Ebola infections which are
characterized by GI (vomiting & diarrhea) and respiratory (cough and
expectoration of sputum) shedding of the intact infectious virus. The
monkeys in this year’s study simply died too fast, not allowing time for
them to shed infectious Ebola particles. It goes without saying that
monkeys which do not shed infectious Ebola particles cannot transmit
Ebola to other monkeys. Had this year’s rhesus monkeys been infected by
the nasal route, as was the case in a pig-to-monkey experiment in 2012,
or if they had lived up to 13 days as in the 1995 study, allowing time
for intact infectious Ebola virus to appear, and thus more closely
matching human Ebola disease, then we may well have seen
monkey-to-monkey airborne transmission of Ebola. The authors of this study concluded that:
“NHPs [non-human primates such as monkeys] are known to be susceptible to lethal EBOV infection through the respiratory tract [just like humans] putting the onus of the transmission on the ability of the source to shed infectious particles.”
We
know that airborne transmission of Ebola occurs from pigs to monkeys in
experimental settings. We also know that healthcare workers like Dr. Kent Brantly are
contracting Ebola in West Africa despite CDC-level barrier protection
measures against physical contact with the bodies and body fluids of
Ebola victims, so it only makes sense to conclude that some -- possibly
many -- of these doctors, nurses, and ancillary healthcare workers are
being infected via airborne transmission. It makes perfect sense that
sick humans, as they vomit, have diarrhea, cough, and expectorate
sputum, and as medical procedures are performed on them, have the
ability to shed infectious Ebola particles into the air at a similar or
higher level compared to Sus scrofa (wild boar) in the pig-to-monkey study.
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