In 1999 2.4 million U.S. Armed Forces personnel, including more than one
million reserve and National Guard members, were ordered to receive anthrax vaccine over a
period of several years.
This was justified to counter an increasing threat from hostile countries and possibly terrorist groups that now or in the future will likely possess the capability of fielding weaponized anthrax spores as a Biological Weapon (BW). This decision has resulted in courts-martial and disciplinary hearings among U.S. Armed Forces personnel who have refused the anthrax vaccine on safety grounds. Are these individuals overreacting to misperceived risks from the anthrax vaccine that the military considers safe, or are there real safety concerns that should be considered?
Bacillus anthracis as a BW Agent
Bacillus anthracis is a relatively common spore-forming soil bacterium found rarely in the U.S. but more commonly in some areas of the world as an endogenous infectious agent. Bacillus anthracis infection can cause death within six days of exposure to a lethal dose, usually by inhalation of spores. To be effective as a BW agent a microorganism must be highly infectious, very pathogenic and stable in the air and environment for the period of time needed for dissemination and infection of large numbers of people. Spore-forming bacteria like Bacillus anthracis are ideal for this purpose.
Spores are relatively inactive metabolically and are much more resistant to sunlight, heat, dryness and chemicals than the replicating microorganism. Weaponized versions of anthrax spores are more pathogenic and survive better than spores from native strains of Bacillus anthracis. It is estimated that as few as 50,000 weaponized anthrax spores can kill a human after inhalation and fewer can kill small primates.
Although weaponized anthrax spores are probably the most easily manufactured BW weapon, they are only one of dozens of lethal and incapacitating (causing nonlethal sicknesses) BW agents that have been produced in large quantities suitable for BW deployment and tactical use. Bacillus anthracis is also one of the few BW agents for which a vaccine exists that is capable of preventing some (but not all) lethal infections. Although dozens of additional microbial candidates for BW have been produced in various quantities by several countries, such as bacteria (Clostridium botulinum, Brucella melitensis, Yersinia pestis, Clostridium perfringens, Bacillus cereus, Francisella tularensis, Coxiella burnetii, among others), toxins (ricin, aflatoxin, Clostridium botulinum toxin, Staphylococcal enterotoxin B toxin, tricothecene mycotoxins, etc.), viruses (Ebola, West Nile fever, Marburg, small pox, etc.) and miscellaneous BW (rickettsias, mycoplasmas, fungi, etc.), weaponized Bacillus anthracis is considered one of the greatest threats because of the ease of its production, storage and dissemination (spores) as a lethal BW agent.
There are basically three methods to counter anthrax BW: active immunization, passive immunization and prophylactic antibiotics. Antibiotics have to be administered shortly before or after exposure, otherwise they wont be effective, and they cannot prevent a lethal infection once the Bacillus anthracis has produced signs of illness. Passive immunoprophylaxis requires quantities of immune sera or monoclonal antibodies not currently available, and their administration in a monitored, hospital setting. Active immunity using vaccines on the other hand can be administered years before exposure as long as immunity is maintained. Thus vaccines can be effective as long as there is enough immunity to neutralize the Bacillus anthracis before it starts rapidly replicating en masse from its inactive spore form and producing lethal toxins. From a practical standpoint, only antibiotics and vaccines can protect the large numbers of people who could be exposed in a BW attack, and antibiotics are more effective when the BW agent(s) and its(their) antibiotic sensitivity are identified so the appropriate antibiotic(s) can be used.
Are anthrax vaccines then a reliable method of protecting against Bacillus anthracis BW? Not necessarily. Although vaccines can protect against accidental exposure of relatively small doses of anthrax spores that infect skin wounds, such as encountered occasionally in meat processing, it remains unproven whether anthrax vaccines will actually protect against a lethal aerosol dose of inhaled anthrax spores of the weaponized variety that are used as BW agents. This is especially true if mixtures of BW agents are used instead of single BW agents.
The Anthrax Vaccine: Safety Concerns
The anthrax vaccine in use remains unproven in its ability to stop a lethal dose of weaponized Bacillus anthracis spores, and there are questions about its safety. According to the U.S. Army Medical Research Institute for Infectious Disease (USAMRIID) at Fort Detrick, MD, the anthrax vaccine used by the military was determined to be safe, and adverse reactions were found to occur only at the rate of one per 50,000 doses (less than 0.002%). This has now been revised to a rate of 0.02-0.2% or higher. Moreover, in recent testimony by one of us [M.N.] to the National Academy of Sciences the safety of the anthrax vaccine and the rates of adverse reactions were questioned. Using Dover AFB as an example, the rate of chronic health problems after receiving the anthrax vaccine may be as high as 7%. The difference is that the official rates are for acute reactions only. The Department of Defense (DoD) claims that the rate for vaccine chronic reactions is zero.
A major part of the problem in assessing vaccine safety is in how vaccine adverse effects are reported. Many people who suffer from adverse anthrax vaccine effects are reluctant to step forward to seek medical care, because
they have seen their colleagues' concerns dismissed as due to depression or stress. They also fear that they could lose their ability to perform their duties, as a number of the pilots and airmen at Dover AFB are now on DNIF (duties not including flying) status because of undiagnosed illnesses that began after they received their anthrax vaccinations. Lt. Colonel Randy Randolf, director of the U.S. Armys vaccination program, counters that all vaccines, the anthrax vaccine included, can produce adverse effects, such as soreness, redness, itching, swelling, and lumps at the injection site. He has stated that about 30% of men and 60% of women report these local reactions, but they usually last only a short time. Lt. Col. Randolf further describes that beyond the injection site, from 5% up to 35% of people have noticed muscle aches, joint aches, headaches, rash, chills, fever, nausea, loss of appetite, malaise, or related symptoms. It is commonly thought that these symptoms go away after a few days, and apparently there has been no completed studies of long-term side effects of anthrax vaccine using active surveillance. Although the DoD began such a study at Tripler Army Medical Center, Honolulu in September, 1998, they have yet to release any preliminary data on long-term problems that developed after anthrax vaccination.
The difference between what military and civilian physicians conclude about adverse reactions and the anthrax vaccine seems to be based on whether you accept that vaccines can cause chronic illnesses beyond the initial reporting period of vaccine adverse effects. The high incidence of unusual chronic health problems at Dover AFB include systemic signs and symptoms, such as vomiting, diarrhea, polyarthralgias, fever, splenic tenderness, cognitive problems, polymyalgias, weakness and numbness, and these problems can occur well after the usual reporting period for vaccine adverse effects. Patients with preexisting autoimmune illnesses such as rheumatoid arthritis, lupus, multiple sclerosis, among others, are probably more likely to suffer a serious adverse reaction, as are those with neurologic disease, such as those who had polio in childhood. Stevens Johnson Syndrome, a severe allergic reaction in which there is loss of epidermis (skin) and the lining of the GI tract, was found in some patients as well as more classic allergic signs and symptoms. Even more serious, many anthrax vaccine recipients report seizures with complete loss of consciousness. Respiratory distress and a variety of pulmonary illnesses have also been reported. Because these types of reactions have rarely been identified with other vaccines and because few of those reporting illness have been subjected to an exhaustive medical evaluation, including sophisticated immunological testing, the mechanisms by which anthrax vaccine may be causing illnesses have not been elucidated. Furthermore, the entire stockpile of anthrax vaccine is owned by the DoD, and none has yet been made available for thorough, independent testing.
The Anthrax Vaccine: Source
One of the most difficult problems in dealing with anthrax vaccine safety is obtaining specific information on the anthrax vaccine and how it was determined to be safe. Most military vaccines in the U.S. are from sole-source manufacturers. In the case of FDA-approved vaccines, a number of strict production and safety requirements must be fulfilled, and evidence for effectiveness in humans must be presented to the FDA before approval for production and sale is granted. However, in the case of the anthrax vaccine there seem to be missing elements in this safety net.
The sole producer of the anthrax vaccine was originally Michigan Biologic Products, Inc., a state-owned corporation that obtained U.S. Government approval for the anthrax vaccine at a time when FDA approval was not required. The anthrax vaccine was approved by the Bureau of Biologics at NIH in 1970, two years before efficacy data and approval were required by the FDA. In the case of the anthrax vaccine, long-term safety data were not supplied with the license application, and none has yet been supplied to the FDA. As it turns out, the Bacillus anthracis vaccine now being produced may be different or the procedure for vaccine preparation modified from the original vaccine approved by NIH. The usual requirement is that any new product or modification in preparation must be examined and approved by the FDA, but the FDA has apparently not examined or approved every modification made to the current vaccine for anthrax.
The original license and the facility producing the anthrax vaccine was owned by Michigan Biologic Products, Inc. of the Michigan State Department of Health. The new owner of both is a company called Bioport, Inc., owned by a group of investors lead by Admiral William Crowe, Jr., former head of the Joint Chiefs of Staff, DoD, and Faud El-Hibri, a German citizen of Lebanese descent who has since obtained American citizenship. The facility was sold to Admiral Crowes investor group after the DoD decided to vaccinate all of its servicemen and servicewomen against anthrax. Recently Bioport ran into financial problems and negotiated a series of changes in its DoD contract that increases by three-fold the per dose price of the anthrax vaccine supplied to the military. This and other problems have resulted in a congressional investigation into the financial relationship between DoD and the new owners of Bioport, which may constitute a conflict of interest.
The Anthrax Vaccine: Safety
Problems with the anthrax vaccine have raised questions about previous vaccine programs. The former commander of the USAMRIID, Dr. Phillip Russell, admitted in an infectious disease journal (Infectious Disease Clinics of North America, 1990) that unlicensed anthrax vaccines were used on Armed Forces personnel before the Gulf War. There is, of course, no record of safety available for unlicensed vaccines. In fact, there were no published studies of safety or efficacy for the current anthrax vaccine until very recently, well after the decision was made to vaccinate. A recent brief publication from the USAMRIID in JAMA provides some safety information about the anthrax vaccine, but it refers to previously unpublished data that are not available for evaluation.
The normal procedure for post-marketing vaccine evaluation requires that the FDA must review adverse vaccine reactions collected through the Vaccine Adverse Event Reporting System (VAERS). Adverse events are usually recorded independently by a FDA-approved contractor. The contractor then sends their data to the FDA, and the FDA assembles a committee that then evaluates adverse events for the likelihood that the vaccine might have caused them, and it can recommend further study. However, in the case of the anthrax vaccine, military physicians were instructed that only certain adverse effects could be vaccine reactions, such as classic immediate allergic reactions, and others, such as joint pain, cognitive disturbances, etc. could not be due to the vaccine. Physicians treating these patients had no access to published data on anthrax vaccine side effects, and there is no entry for anthrax vaccine in the Physicians Desk Reference (PDR). The package insert for the vaccine is based on data collected from an earlier anthrax vaccine, and it does not list the range of possible reactions that could occur. Thus
until recently none of the long-term chronic effects of the vaccine were even reported by medical providers. In the case of the anthrax vaccine, only reactions that resulted in hospitalization or immediate loss of 24 hours of duty time were reported to a military clearing-house for vaccine reactions. This has changed recently, and it appears now that other adverse vaccine effects will be entered in the medical records of patients, but whether they are always reported remains questionable. We feel strongly that traditional and accepted means of FDA vaccine evaluation must be implemented for military vaccines, just as they are required for commercial vaccines. Only then can the safety of the anthrax vaccine be evaluated. The anthrax vaccine should be treated just like any other commercial vaccine and not given special waivers or treatment in the evaluation process. Only then will the public be satisfied that the current anthrax vaccine is safe.
The Anthrax Vaccine: Quality
For years Michigan Biologic Products Inc. had been warned by the FDA of intent to revoke their license to produce vaccines because of violations in the production and testing of their vaccines. As recently as 1997, MBPI received formal written notification from the FDA that they had not complied with FDA-mandated requirements. However, since MBPI was the only manufacturer of anthrax vaccine, they were given a waiver and allowed to remain open, pending FDA compliance. During this time vaccine lots were distributed to the military. In 1998 some of these vaccine lots were retested, and only 6 out of 31 lots passed initial supplemental testing. Most of the retested vaccine lots had expired or had been redated for an additional 3-year period once or even twice. This is obviously unacceptable.
The question has been raised whether expired or failed vaccine lots were used for vaccinating military personnel during the Gulf War. Since supplemental testing on anthrax vaccines used in the Gulf War was not undertaken, and some of these lots apparently also had previously expired and had been redated, some personnel could have received out-of-date vaccines, or worse, contaminated vaccines. Information is not available on whether U.S. Forces received contaminated vaccines (no such testing has been made public), but the British Gulf War veterans report that several vaccine lots from the Gulf War were reported to be contaminated with unknown microorganisms. Thus some of the health problems associated with the anthrax vaccine could be related to possible vaccine contamination.
Vaccines and the Gulf War
Before military personnel were deployed to the Persian Gulf Theater of Operations, they had to pass physical examinations and be fit for active duty. After passing their physical exams, they received several types of vaccinations, mostly with commercially available vaccines. In the Persian Gulf area this was usually done by administering as many as two dozen vaccine doses over a period of a few days, even if the vaccines were normally required to be given over a course of several months to over a year. In contrast to previous wars, service personnel were not allowed to keep a record of these vaccinations, and according to the DoD the shot records of hundreds of thousands of deployed personnel have since disappeared. Some health personnel administering the vaccines were also warned that they would be courts-martialed if they kept any record of vaccines given to military personnel. According to nurses that took part in the vaccination program, many soldiers became sick after the vaccines were given, but few were allowed to report the adverse effects of the vaccines, unless they were hospitalized. Most had to return to active duty, even if they suffered adverse effects directly attributable to the vaccines. The records of these adverse effects are for the most part also missing.
The problem with administering multiple vaccines all at once is that this can result in immune-depression and leave individuals susceptible to opportunistic infections, such as the types that the vaccines were supposed to protect against. To be effective, the vaccines used in the Gulf War should have been given in several steps, the initial vaccination followed by several boosters given over months to over a year to maximize immunity. If given all at once, these vaccines are more likely to cause adverse reactions and produce diminished immunity be useless in protecting an individual, and they may even make the vaccinated person more susceptible to opportunistic infections due to immune-suppression.
Gulf War Illnesses and Vaccines
Between 100,000-200,000 veterans of the Persian Gulf War in 1991 now have Gulf War Illnesses (GWI), which are characterized by complex, multi-organ chronic signs and symptoms. These include chronic fatigue, headaches cognitive problems, nausea, gastrointestinal problems, vomiting, diarrhea, polyarthralgias, fever, splenic tenderness, polymyalgias, among other signs and symptoms. Often these patients show the appearance of rheumatic and other autoimmune signs and symptoms. The signs and symptoms of GWI overlap with Chronic Fatigue Syndrome (CFS) or Myalgic Encephalomyelitis (ME), and often they meet the criteria for the diagnosis of CFS/ME or Fibromyalgia syndrome (FMS) where the distinguishing feature is the presence of chronic widespread muscle pain and tenderness. Often included in this complex clinical picture are increased sensitivities to various environmental agents and enhanced allergic responses. There are other clinical problems in these patients, including impaired cardiac function, increases in spontaneous abortions and other chronic signs. The signs and symptoms reported by many anthrax vaccine recipients also overlap with GWI.
In some cases GWI has spread to immediate family members. Although incomplete, a 1994 report by investigators of a U.S. Senate committee found after contacting approximately 1,200 GWI families that ~77% of spouses and ~65% of children born after the war developed the chronic signs and symptoms of GWI. Although officially denied by the U.S. DoD and British Ministry of Defense, this indicates that at least a subset of GWI patients have a illness that is being passed to spouses and children. Since some of the GWI patients have an illness that is transmissible to family members and perhaps others as well, these GWI cases cannot be explained solely on the basis of chemical or radiological exposures, or the even more unlikely cause of battlefield stress leading to Post Traumatic Stress Disorder.
Although stress can induce some illness, the General Accounting Office (GAO), the investigational arm of the U.S. Congress, after studying government and civilian data on GWI, concluded that the link between stress and GWI was not established. Of course, stress can exacerbate chronic illness but most military personnel indicated to us that the Gulf War was not a particularly stressful war, and they strongly doubted that stress was the origin of their illnesses. However, in the absence of physical or laboratory tests that could identify possible origins of GWI, many physicians accepted that stress was the cause of GWI or that it was caused by combinations of chemical exposure and stress. A recent psychiatric study indicates that patients with GWI do not fit the classical picture of stress related illness.
If stress is added to multiple vaccines given at once, plus chemical and other toxic exposures encountered during the Gulf War, then immune suppression and opportunistic infections could be a likely outcome in at least a subset of the military personnel that subsequently came down with GWI. This would also explain in some cases the apparent transmission of illness to immediate family members and the occurrence of GWI in some vaccinated forces that were not deployed.
Vaccine Contamination and Gulf War Illnesses
Testing of commercial vaccine lots demonstrates that contamination can and does occur. A common vaccine contaminant is Mycoplasma species of the class Molecutes, small cell wall-deficient bacteria lacking many of the genes involved in macromolecular and lipid synthesis. Although not widely appreciated for their ability to cause disease, mycoplasmas have been implicated in a variety of chronic illnesses, including CFS/ME, FMS, Rheumatoid Arthritis and GWI. When we examined thousands of GWI patients for evidence of blood mycoplasmal infections, we found evidence of mycoplasmas in about one-half of GWI cases, and in particular, one species of mycoplasma, Mycoplasma fermentans, was found at high incidence. M. fermentans has been examined over the last decade or so by the Armed Forces Institute of Pathology for its role in causing a progressive, non-HIV AIDS-like fatal disease that has many of the hallmarks of GWI.
Mycoplasmas like M. fermentans could be involved in the transmission of GWI to immediate family members. When symptomatic family members of veterans with GWI were tested for the presence of mycoplasmal infections in their blood, they were found to have the same species of mycoplasma as found in the sick veteran family member. In addition, most of these patients responded to the appropriate antibiotics and eventually recovered, albeit slowly, from their illness, similar to what we have seen in CFS/ME, FMS and Rheumatoid Arthritis patients with mycoplasmal infections. When recovered patients were retested for mycoplasmal blood infections, they were no longer positive for Mycoplasma species in their blood samples. This suggests that mycoplasmal infections could be causing at least some if not most of the signs and symptoms of GWI found in these patients, and these infections can be passed to family members who then develop similar illnesses.
What remains to be determined is whether the vaccines used in the Gulf War were the source of the mycoplasmas found in veterans blood. A study reporting the presence of antibodies to an unlicensed vaccine adjuvant in over 90% of the GWI patients evaluated has just been published. This strongly suggests that experimental vaccines were used in the Gulf War. Experimental vaccines are unapproved vaccines without available safety and efficacy data. Although listed as our number one possible source of the infections found in GWI patients, vaccines are not the only possible source of microorganisms from the Gulf War. In our sworn testimony to the U.S. Congress [G.L.N., N.L.N.] we stated that there were several potential sources of chronic biological agents in the Gulf War. The Iraqis were known to have extensive stockpiles of BW agents and the potential to deliver these weapons offensively, at short range in modified Italian-made biological sprayers that deliver BW agents onto the sand to create exclusionary zones or 'biological minefields' and at long range in modified SCUD-B (SS-1) missiles with 'airburst' warheads or sprayers carried by aircraft. Many of the storage and factory facilities where BW agents were stored were destroyed immediately up to, during and after the Desert Storm ground offensive, releasing plumes containing these agents high in the atmosphere where they could be carried downwind ('blow-back' exposures) to our lines. These and other possible mechanisms of potential exposure must be carefully examined as well as the possible role of mycoplasmas and other chronic infections in GWI patients.
War, Terrorism and BW Attacks
If BW agents are ever deployed in war or terrorist attacks, many times the lethal (human) dose could be encountered in an aerosolized BW and chemical mixture that is designed to inhibit and overwhelm the bodys defensive abilities. These mixtures, called Russian Doll Cocktails, contain microorganisms plus immune inhibitors and other chemicals to impede the immune systems ability to contain the infection by blocking pulmonary defenses. The pulmonary immune system, particularly the pulmonary macrophage, is the first level of defense against inhaled foreign microorganisms and its suppression could result in systemic infection. BW use on the battlefield of the future will likely involve multiple BW agents, not just one or even a few agents. Countries like Iraq operate under Soviet War Doctrine, a battle strategy that stresses combinations of conventional and unconventional weapons. Thus combinations of multiple BW, CW (Chemical Warfare) or even NW (Nuclear Warfare) agents may be used together to heighten BW virulence and confuse the diagnosis and treatment of casualties. The rationale is to overwhelm a medical corps ability to effectively manage large numbers of casualties with unknown or incomplete diagnoses. Iraqi Field Manuals found during the Gulf War described this strategy in detail. Unfortunately, BW can be developed and produced at a fraction of the cost of other weapons of mass destruction, making it likely that future terrorists will choose BW agents over other weapons for terrorist attacks.
The U.S. militarys strategy of defense against BW agents is prior immunization using multiple vaccines. Unfortunately, this can only be successful if the exact BW agents likely to be encountered are known in great detail and for some time in advance of exposure. For example, the vaccine against Bacillus anthracis requires a rather lengthy immunization protocol, administering multiple vaccine and booster doses over more than a year. If multiple vaccines were to be administered, then they would have to be administered at different times to prevent immune suppression or excessive stimulation. Obviously, this strategy requires advance knowledge of the threat and careful long-term preparation against the threat. To prepare for any new threat that arises will require some time, possibly years or over a decade. Recent reports have appeared indicating that the Russians have developed anthrax strains for which it is claimed protective vaccines do not exist. What is the evidence that our multivalent Bacillus anthracis vaccine will protect against all known anthrax strains?
Protection against BW Attacks
Other strategies besides the vaccine approach to BW defense are available. During the Gulf War the French forces elected not to use vaccines as a primary defense against Iraqi BW and not to use anti-nerve agents as a defense against Iraqi Chemical Warfare agents. Instead, they used prophylactic antibiotics to counter Iraqi BW agents, and they depended on protective suits to counter Iraqi chemicals. Interestingly, the French Armed Forces were the only nation in the Coalition Forces that did not report any cases of GWI, nor were there any illnesses reported in the immediate families of French Gulf War veterans.
What assurances do we have that future vaccines will be free of microbial contamination that could cause disease? Obviously, the purity and safety of vaccines depend on their ability to remain free of contamination by microorganisms. FDA-mandated vaccine preparation methods are generally considered adequate to prevent this possibility, but unless each batch or lot of vaccine is routinely tested for possible contamination, including animal testing, this remains a possibility that must be carefully examined, not uncritically dismissed by untrained bureaucrats as a remote hypothetical possibility.
If prophylactic antibiotic or antiviral agents are used for BW defense, can these be defeated? Yes, BW agents can be modified or constructed that have integrated into their genomes antibiotic- or antiviral-resistance genes. Similar to the engineering of more lethal BW agents to circumvent known vaccines, such microorganisms can be engineered to resist specific antibiotic or antiviral agents. Interestingly, certain U.S. units were issued antibiotics like ciprofloxacin and doxycycline just before the ground offensive in the Gulf War. These antibiotics would be expected to be effective in preventing infections of at least two of the agents identified in veterans with Gulf War Illness (Mycoplasma fermentans and Brucella spp.). Examination of the numbers, deployments and types of casualties and their diagnoses in the units administered antibiotics before and during the Gulf War could tell us if the French approach to BW defense was more or less effective than our approach of administering multiple vaccines to prevent BW casualties.
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