- As I have been warning for nearly ten years now,
we are past the age of 'sterilization' with full certainty as medical and dental
sciences have commonly known it.
-
- No longer can 'sterilized' medical and dental instruments
be used with complete confidence that they cannot and do not spread
vCJD/Mad Cow - and now Morgellons Disease - to patients undergoing
procedures with invasive and heretofore 're-usable' dental and medical
instruments.
-
- Autoclaves used for sterilizing re-usable instruments
operate in a temperature range of 250-350 F. Mad Cow/CJD prions can
withstand temperatures of over 1,000F...and Morgellons fibers can
survive temperatures of nearly 1400F.
-
- Both I, and Dr. Patricia Doyle PhD, have stated for many
years that we should move to SINGLE USE invasive medical and dental
instruments immediately to ensure the safety of all patients and staff
from CJD...the human form of Mad Cow...and now from Morgellons Disease.
-
- In a major new report from SEAC, the UK Spongiform Encephalopathy
Advisory Committee, it is now clearly stated that there are legitimate
risks for the spread of CJD, vCJD (Mad Cow) in routine dental procedures.
-
- Here are three excerpts from the SEAC report the report
below:
-
- "The new research also suggests that dental procedures
involving contact with other oral tissues, including gingiva, may also
be capable of transmitting vCJD."
-
- "14. Preliminary research findings suggest that
the potential risk of transmission of vCJD via dental procedures may be
greater than previously anticipated."
-
- "15. Guidance was issued to dentists earlier this
year recommending that endodontic files and reamers (rotating drill heads
which grind teeth enamel ...ever had a filling?) be treated as SINGLE
USE (instruments) which, provided it is adhered to,
will remove any risk of a self-sustaining vCJD (Mad Cow) epidemic
arising from re-use of these instruments."
-
-
- The following complete SEAC report was kindly sent by
Terry S. Singletary who has been rigorously following and researching the
transmission dynamics of vCJD (Mad Cow Disease) for many years. In Terry's
own words...
-
- "My name is Terry S Singeltary Sr, and I live in
Bacliff, Texas. I lost my mom to hvCJD (Heidenhain variant CJD) and
have been searching for answers ever since. What I have found is that we have
not been told the truth. CWD in deer and elk is a small portion of
a much bigger problem."
-
- What Is SEAC (UK)?
-
- In April 1990, the Consultative Committee on Research
(CCR) was re-established as the Spongiform Encephalopathy Advisory Committee
(SEAC), with a wider remit to advise the former MAFF, now Defra, Department
of Health (DH) and later, in 2002, the Food Standards Agency (FSA), on
matters related to transmissible spongiform encephalopathies (TSEs) and
effectively assuming the role of the Southwood Working Party and the CCR.
-
- Here is the report...
-
- SEAC Position Statement On vCJD Transmission Risks In
Dentistry
-
- Issue
-
- 1. The Department of Health (DH) asked SEAC to advise
on the findings of preliminary research aimed at informing estimates of
the risk of variant Creutzfeldt-Jakob Disease (vCJD) transmission via dentistry.
-
- Background
-
- 2. Prions are more resistant than other types of infectious
agent to the conventional cleaning and sterilisation practices used to
decontaminate dental instruments1. Appreciable quantities of residual material
may remain adherent to the surface after normal cleaning and sterilisation2.
Therefore, if dental tissues are both infectious and susceptible to infection,
then dental instruments are a potential mechanism for the secondary transmission
of vCJD. Dentistry could be a particularly significant route of transmission
for the population as a whole, due to the large number of routine procedures
undertaken and also because dental patients have a normal life expectancy.
This is in contrast with other transmission routes, such as blood transfusion
and neurosurgery, where procedures are often carried out in response to
some life-threatening condition. Additionally, the ubiquity of dental procedures
and the lack of central records on dental procedures means that should
such transmission occur, then it would be difficult to detect and control.
-
- 3. No cases of vCJD transmission arising from dental
procedures have been reported to date 3 . Previous DH risk assessments4,5
have focused on two possible mechanisms for the transfer of vCJD infectivity
via dental instruments; accidental abrasion of the lingual tonsil and endodontic
procedures that involve contact with dental pulp. In considering these
assessments, SEAC agreed that the risk of transmission via accidental abrasion
of the lingual tonsil appears very low. However, the risk of transmission
via endodontic procedures may be higher and give rise to a self sustaining
vCJD epidemic under circumstances where (i) dental pulp is infective, (ii)
transmission via endodontic instruments is efficient and (iii) a large
proportion of vCJD infections remain in a subclinical carrier state (SEAC
91, February 2006). In light of this, SEAC advised that restricting endodontic
files and reamers to single use be considered 6. SEAC recommended reassessment
of these issues as new data emerge.
-
- New Research
-
- 4. Preliminary, unpublished results of research from
the Health Protection Agency, aimed at addressing some of the uncertainties
in the risk assessments, were reviewed by SEAC (SEAC 97, May 2007). The
prion agent used in these studies is closely related to the vCJD agent.
This research, using a mouse model, shows that following inoculation of
mouse-adapted bovine spongiform encephalopathy (BSE) directly into the
gut, infectivity subsequently becomes widespread in tissues of the oral
cavity, including dental pulp, salivary glands and gingiva, during the
preclinical as well as clinical stage of disease.
-
- 5. It is not known how closely the level and distribution
of infectivity in the oral cavity of infected mice reflects those of humans
infected with vCJD, as there are no comparable data from oral tissues,
in particular dental pulp and gingiva, from human subclinical or clinical
vCJD cases7. Although no abnormal prion protein was found in a study of
human dental tissues, including dental pulp, salivary glands and gingiva
from vCJD cases , the relationship between levels of infectivity and abnormal
prion protein is unclear8. Infectivity studies underway using the mouse
model and oral tissues that are presently available from human vCJD cases
will provide some comparable data. On the basis of what is currently known,
there is no reason to suppose that the mouse is not a good model for humans
in respect to the distribution of infectivity in oral tissues. Furthermore,
the new data are consistent with published results from experiments using
a hamster scrapie model9 .
-
- 6. A second set of experiments using the same mouse model
showed that non-invasive and transient contact between gingival tissue
and fine dental files contaminated with mouse-adapted BSE brain homogenate
transmits infection very efficiently. It is not known how efficient gingival
transmission would be if dental files were contaminated with infectious
oral tissues and then subsequently cleaned and sterilised, a situation
which would more closely model human dental practice. Further studies using
the mouse model that would be more representative of the human situation,
comparing oral tissues with a range of doses of infectivity, cleaned and
sterilised files and the kind of tissue contact with instruments that occurs
during dentistry, should be considered.
-
- 7. SEAC considered that the experiments appear well designed
and the conclusions justified and reliable, while recognising that the
research is incomplete and confirmatory experiments have yet to be completed.
It is recommended that the research be completed, submitted for peer-review
and widely disseminated as soon as possible so others can consider the
implications. Nevertheless, these preliminary data increase the possibility
that some oral tissues of humans infected with vCJD may potentially become
infective during the preclinical stage of the disease. In addition, they
increase the possibility that infection could potentially be transmitted
not only via accidental abrasion of the lingual tonsil or endodontic procedures
but a variety of routine dental procedures. Implications for transmission
risks
-
- 8. The new findings help refine assumptions made about
the level of infectivity of dental pulp and the stage of incubation period
when it becomes infective in the risk assessment of vCJD transmission from
the reuse of endodontic files and reamers10. For example, if one patient
in 10 000 were to be carrying infection (equivalent to about 6 000 people
across the UK the best current estimate11), the data suggest that
in the worst case scenario envisaged in the risk assessment, re-use of
endodontic files and reamers might lead to up to 150 new infections per
annum. It is not known how many of those infected would go on to develop
clinical vCJD. In addition, transmission via the re-use of endodontic files
and reamers could be sufficiently efficient to cause a self-sustaining
vCJD epidemic arising via this route.
-
- 9. These results increase the importance of obtaining
reliable estimates of vCJD infection prevalence. Data that will soon be
available from the National Anonymous Tonsil Archive may help refine this
assessment and provide evidence of the existence and extent of subclinical
vCJD infection in tonsillectomy patients. Further data, such as from post
mortem tissue or blood donations, will be required to assess prevalence
in the general UK population12.
-
- 10. Recent guidance issued by DH to dentists to ensure
that endodontic files and reamers are treated as single use13 is welcomed
and should, as long as it is effectively and quickly implemented, prevent
transmission and a self-sustaining epidemic arising via this route. However,
the extent and monitoring of compliance with this guidance in private and
National Health Service dental practice is unclear.
-
- 11. The new research also suggests that dental procedures
involving contact with other oral tissues, including gingiva, may also
be capable of transmitting vCJD. In the absence of a detailed risk assessment
examining the potential for transmission via all dental procedures, it
is not possible to come to firm conclusions about the implications of these
findings for transmission of vCJD. However, given the potential for transmission
by this route serious consideration should be given to assessing the options
for reducing transmission risks such as improving decontamination procedures
and practice or the implementation of single use instruments.
-
- 12. The size of the potential risk from interactions
between the dental and other routes of secondary transmission, such as
blood transfusion and hospital surgery, to increase the likelihood of a
self-sustaining epidemic is unclear.
-
- 13. It is likely to be difficult to distinguish clinical
vCJD cases arising from dietary exposure to BSE from secondary transmissions
via dental procedures, should they arise, as a large proportion of the
population is likely both to have consumed contaminated meat and undergone
dentistry. However, an analysis of dental procedures by patient age may
provide an indication of the age group in which infections, if they occur,
would be most likely to be observed. Should the incidence of clinical vCJD
cases in this age group increase significantly, this may provide an indication
that secondary transmission via dentistry is occurring. Investigation of
the dental work for these cases may provide supporting data. There is no
clear evidence, to date, based on surveillance or investigations of clinical
vCJD cases, that any vCJD cases have been caused by dental procedures but
this possibility cannot be excluded.
-
- Conclusions
-
- 14. Preliminary research findings suggest that the potential
risk of transmission of vCJD via dental procedures may be greater than
previously anticipated. Although this research is incomplete, uses an animal
model exposed to relatively high doses of infectivity, and there are no
data from infectivity studies on human oral tissues, these findings suggest
an increased possibility that vCJD may be relatively efficiently transmitted
via a range of dental procedures. Ongoing infectivity studies using human
oral tissues and the other studies suggested here will enable more precise
assessment of the risks of vCJD transmission through dental procedures.
-
- 15. Guidance was issued to dentists earlier this year
recommending that endodontic files and reamers be treated as single use
which, provided it is adhered to, will remove any risk of a self-sustaining
epidemic arising from re-use of these instruments. To minimise risk it
is critical that appropriate management and audit is in place, both for
NHS and private dentistry.
-
- 16. It is also critical that a detailed and comprehensive
assessment of the risks of all dental procedures be conducted as a matter
of urgency. While taking into account the continuing scientific uncertainties,
this will allow a more thorough consideration of the possible public health
implications of vCJD transmission via dentistry and the identification
of possible additional precautionary risk reduction measures. The assessment
will require continued updating as more evidence becomes available on the
transmissibility of vCJD by dental routes, and on the prevalence of infection
within the population. A DH proposal to convene an expert group that includes
dental professionals to expedite such an assessment is welcomed. Given
the potential for transmission via dentistry, consideration should be given
to the urgent assessment of new decontamination technologies which, if
proved robust and effective, could significantly reduce transmission risks.
-
- SEAC
- June 2007
-
- References
- 1 Smith et al. (2003) Prions and the oral cavity. J.
Dent. Res. 82, 769-775.
-
- 2 Smith et al. (2005) Residual protein levels on reprocessed
dental
- instruments. J. Hosp. Infect. 61, 237-241.
-
- 3 Everington et al. (2007) Dental treatment and risk
of variant CJD a case
- control study. Brit. Den. J. 202, 1-3.
-
- 4 Department of Health. (2003) Risk assessment for vCJD
and dentistry.
-
- 5 Department of Health (2006) Dentistry and vCJD: the
implications of a
- carrier-state for a self-sustaining epidemic. Unpublished.
-
- 6 SEAC (2006) Position statement on vCJD and endodontic
dentistry.
- http://www.seac.gov.uk/statements/statement0506.htm
-
- 7 Head et al. (2003) Investigation of PrPres in dental
tissues in variant
- CJD. Br. Dent. J. 195, 339-343.
-
- 8 SEAC 90 reserved business minutes.
-
- 9 Ingrosso et al. (1999) Transmission of the 263K scrapie
strain by the
- dental route. J. Gen. Virol. 80, 3043-3047.
-
- 10 Department of Health (2006) Dentistry and vCJD: the
implications of a
- carrier-state for a self-sustaining epidemic. Unpublished.
-
- 11 Clarke & Ghani (2005) Projections of future course
of the primary vCJD
- epidemic in the UK: inclusion of subclinical infection
and the possibility
- of wider genetic susceptibility R. J. Soc. Interface.
2, 19-31.
-
- 12 SEAC Epidemiology Subgroup (2006) position statement
of the vCJD epidemic.
- http://www.seac.gov.uk/statements/state260106subgroup.htm
-
- 13 DH (2007) Precautionary advice given to dentists on
re-use of instruments
- http://www.gnn.gov.uk/environment/fullDetail.asp?ReleaseID=
- 279256&NewsAreaID=2&NavigatedFromDepartment=False
-
- http://www.seac.gov.uk/statements/state-vcjd-dentrstry.htm
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