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Asunto:[LEA] Environmental Risks of Genetically Engineered Vaccines
Fecha:Miercoles, 15 de Noviembre, 2000  11:44:36 (-0300)
Autor:Amigos en Defensa de la Gran Sabana.AMIGRANSA/ Orinoco Oilwatch <amigrans>

15 November 2000 
Dear friends and colleagues, 
This mail-out is an abstract from the summary of 'An Orphan in Science: 
Environmental Risks of Genetically Engineered Vaccines', a research report 
written for and published by the Directorate for Nature Management of the 
Norwegian Ministry of Environment. <>; 
The report was written by Prof. Terje Traavik, Professor and Head of 
Department of Virology, University of Troms÷ and Director, Norwegian 
Institute of Gene Ecology, Troms÷, Norway. 
According to Prof. Traavik, "...from an ecological and environmental point 
of view many first generation live, genetically engineered vaccines are 
inherently unpredictable, possibly dangerous, and should not be taken into 
wide-spread use until a number of putative problems have been clarified", 
and that "the risks and hazards discussed are most certainly within the 
realm of possibility, and according to the precautionary principle they 
should be subject to preventive measures". 
This report underscores the need to also regulate genetically engineered 
pharmaceuticals and medical applications. At the national level, domestic 
laws and regulations should also cover the use of genetic engineering in 
With best wishes, 
Martin Khor 
Third World Network 
228 Macalister Road 
10400 Penang 
Email: twnet@... 
Doc. TWN/Biosafety/2000/D 
An Orphan in Science: Environmental Risks of Genetically Engineered Vaccines 
Prof. Terje Traavik 
University of Troms÷ and Norwegian Institute of Gene Ecology, Troms÷, Norway 
Some types of genetically engineered or modified vaccines that are now 
being developed pose potential ecological and environmental risks. Such 
vaccines may soon be in widespread use. The risks and hazards are most 
certainly within the realm of possibility, and according to the 
Precautionary Principle they should be subject to preventive measures. In 
practice, however, the risks are considered to be non-existent, since they 
have not been supported by experimental or epidemiological investigations. 
This, again, is a "Catch-22" situation, in the sense that such 
investigations have not been performed at all. 
At the present, the definition of "safety" is very narrow in vaccinology. 
"Safety research" is occupied with prospects of unintended and unwanted 
side effects with regard to the targeted vaccinees themselves, or 
non-targeted individuals within the same species. This narrowing of 
conception and research strategies may leave potential hazards unapprised 
until they actually happen. 
The main purpose of this paper is to raise awareness and catalyze 
discussions. If this in its turn may contribute to having resources 
available for public funding of independent research, the efforts of the 
author have been well rewarded. 
Immunity and vaccination 
Vaccination is a form of prevention or prophylaxis of infectious disease 
and cancers. The reasons for giving priority to prevention and prophylaxis 
are stronger than ever, as development of resistance in microorganisms, 
viruses and cancer cells are reducing the therapeutic opportunities offered 
by chemotherapeutics and antibiotics. 
Through their continual battle with microorganisms and viruses, vertebrates 
have evolved an elaborate set of protective measures collectively termed 
the immune system. Infection with a specific disease agent may initiate 
immunity to that agent, and an individual that is immune to a specific 
infectious agent will be left unharmed when infected by that agent again. 
Vaccination intends to provide individuals with immunological protection 
before an infection actually takes place. However, the immune system is 
very complex, and immunity against different infectious agents is based on 
fine-tuned balances between the various types of cells, signal substances 
and antibodies that make up the total immune system. For some disease 
agents cellular immune reactions are more important, for others specific 
antibodies are essential for protection. Because vaccination against a 
threatening disease may take place many years before exposure to the 
disease-causing agent, immunological memory is a critical factor. A 
long-lived immune response that may be mobilized and augmented rapidly when 
called for is essential. Furthermore, local immunity on the epithelial 
surfaces that are the portals of entrance to the body for most infectious 
agents is very important. 
Until recently, most traditional vaccines were of the "whole disease 
agent"-type: after varying degrees of purification, the whole bacterial 
cell or virus particle was used for immunization. Such vaccines might be 
killed, inactivated or "live". 
By modern techniques, "killed" vaccines may be based on single proteins 
purified extensively to constitute safe preparations with seemingly no side 
effects. However, in general such vaccines have given short-lived general 
immune responses, and weak local immune responses. This may, however, be 
due to rather crude and inadequate delivery systems for such vaccines. 
Live vaccine agents infect the vaccinees, but have had their disease 
provoking abilities attenuated. "Live" vaccines often give stronger 
mobilization of all effector parts of the immune system, and in many 
instances also good local immunity. The most prominent drawback of such 
vaccines is that they may revert to their full disease-causing potential. 
Genetically engineered vaccines and their potential risks 
Synthetic and recombinant vaccines are produced under contained conditions. 
Only a polypeptide which may confer protective immunity to a given disease 
agent are brought out of the production unit and used as vaccine. Such 
vaccines carry the same advantages and disadvantages as traditional 
"killed" or "subunit" vaccines. It is conceivable that new vaccine delivery 
systems and basic knowledge about immune system interactions will make 
these vaccines more efficient in the near future. It is difficult to 
imagine such vaccines posing ecological and environmental risks. 
Genetically modified viruses and genetically engineered virus-vector 
vaccines carry significant unpredictability and a number of inherent 
harmful potentials and hazards. The immunological advantages of such 
vaccines are related to the fact that the viruses are "live" and infect the 
vaccinated individuals. It has, however, been demonstrated that minor 
genetic changes in, or differences between, viruses can result in dramatic 
changes in host spectrum and disease-causing potentials. For all these 
vaccines, important questions concerning effects on other species than the 
targeted one are left unanswered so far. The opportunity of a genetically 
engineered vaccine virus to engage in genetic recombinations with naturally 
occurring relatives is another unpredictable option. The new, hybrid virus 
progenies resulting from such events may have totally unpredictable 
characteristics with regard to host preferences and disease-causing 
potentials. Furthermore, when genetically modified or engineered virus 
particles are broken down in the environment, their nucleic acids will be 
released, representing the same unpredictable risk potentials as the DNA 
and RNA vaccines discussed below. 
Much basic work is needed before recombinant bacterial vectors may be taken 
into practical use. For instance, it was recently demonstrated that 
genetically engineered bacteria might transfer their new gene efficiently 
to indigenous bacteria in the mammalian gut. This potential risk has not 
been investigated for bacteria that are now being genetically engineered as 
oral vaccines. 
Naked DNA vaccines are engineered from general genetic shuttle vectors. 
They are constructed to break species barriers. Naked DNA may persist much 
longer in the environment than dogmas held just a short time ago. 
Consequently, upon release or escape to the wrong place at the wrong time, 
horizontal gene transfer with unpredictable long- and short-term biological 
and ecological effects is a real hazard with such vaccines. There is also 
growing concern about harmful effects due to random insertions of vaccine 
constructs into cellular genomes in target or non-target species. 
RNA vaccines may have a far way to go before any of them find practical 
use. Although easy degradation is a serious problem with RNA work in the 
lab, RNA may be surprisingly resistant under natural conditions. At the 
present time recombination between related RNA molecules has become a real 
concern. RNA recombination is far more common than dogmatic views held 
until recently. 
Genetically engineered plants produce "edible vaccines". Little is known 
about the consequences of releasing such plants into the environment, but 
there are examples of transgenic plants that seriously alter their 
biological environment. A number of unpredicted and unwanted incidents have 
already taken place with genetically engineered plants. 
Some environmental pollutants (xenobiotics, i.e. PCBs, dioxins, heavy 
metals) may interact with genetically engineered vaccines, adding to their 
unpredictability and the inability to perform meaningful risk assessments 
Final remarks 
Changes in attitudes among scientists, medical doctors as well as 
politicians are badly needed. Recent experiences ought to call for humility 
with regard to environmental effects of science and technology. In many 
cases, "experts" were proven wrong after damage had been done. To the 
extent that any prior investigations of damaging effects had been 
undertaken, methods used were inadequate and only capable to reveal 
short-term effects, whereas the long-term impacts were the most important 
and serious. 
There is a most striking lack of holistic and ecological thinking with 
regard to vaccine risks. This seems to be symptomatic for the real lack of 
touch between research in medicine and molecular biology on one hand, and 
potential ecological and environment effects of these activities on the 
In order to make reliable risk assessments, perform sensible risk 
management with regard to genetic engineering in general, and genetically 
engineered vaccines in particular, much pertinent knowledge is lacking. The 
prerequisite for obtaining such knowledge is science and scientists 
dedicated to relevant projects and research areas. It must be the 
responsibility of the national governments and international authorities to 
make funding available for such research. On one hand, this is obviously 
not the responsibility of producers and manufacturers. On the other hand, 
risk-associated research must be publicly funded in order to keep it 
totally independent, which is an absolute necessity for such activities. 
Vaccinology is the "Holy Grail" of medicine. Nevertheless, there are other 
ways of preventing infectious diseases in humans and animals, and these 
should not be ignored. Many of the most burdening infectious agents of 
mankind and its domesticated animals are caused by pathogens that have 
reservoirs and are circulating among wildlife animals. By increasing our 
knowledge about these reservoirs, their occurrence, the transmission routes 
within and out of the indigenous ecosystems, we might be able to break 
transmission chains, or keep our activities out of dangerous ecosystems. 
There is a void in knowledge about the ecological interactions of many 
important pathogens. This field is to some extent subdued by the confidence 
in vaccines, and hence it is a scientific orphan. 
Selected reading: 
A number of relevant references are given in: 
Traavik, T. An Orphan in Science: Environmental risks of Genetically 
Engineered Vaccines. Research Report for DN 1999-6. Directorate of Nature 
Management, Trondheim, Norway, 1999. 
AMIGRANSA.   Sociedad de Amigos en Defensa de la Gran Sabana 
Direccion:   Apartado Postal 50460.Caracas 1050-A. Venezuela 
Tel y Fax   +58 2 992 1884 / Tel +58 2 693 9480 
e-mail:     <amigrans@...> 
Comite Ejecutivo: Ing Alicia Garcia S., Lic. Maria Eugenia Bustamante, 
Arq. Ligia Parra, Lic.Carolina Aular G., Arq. Andreina Zegarra 
La Sociedad de Amigos en defensa de la Gran Sabana es una 
asociacion civil sin fines de lucro,constituida en abril de 1986 
para la preservacion, conservacion y defensa del patrimonio ecologico 
y cultural dela Gran Sabana-Parque Nacional Canaima -Tierra de Tepuis- 
y de todas aquellas areas pertenecientes al Macizo Guayanes, y a la 
defensa de los derechos de los Pueblos indigenas que alli habitan. 
Nos hemos sumado a esta causa por un profundo amor a la naturaleza 
y porque estamos convencidos que el repeto al mundo natural y a 
las leyes ecologicas, son una de las vias primordiales hacia 
el bienestar y la supervivencia de la humanidad. 
AMIGRANSA la integran un grupo de profesionales de distintas 
disciplinas,jovenes estudiantes y una amplia red de colaboradores 
formada por habitantes de la Gran Sabana, cientificos y otros amantes 
de la naturaleza.El trabajo en AMIGRANSA esta basado en el voluntariado. 
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