Adverse reactions to anthrax immunisation in a military field hospital

Radiation Exposure Predicts Reported Vaccine Adverse Effects in Veterans with Gulf War Illness

Most people have no problems when administered vaccines; however, as with all drugs, reported adverse effects (rAEs) do occur. There is a need to better understand the potential predictors of reported vaccine AEs (rVaxAEs), including modifiable (environmental) predictors. Gulf War Veterans (GWV) who have Gulf War illness (GWI) report increased experiences of drug and chemical rAEs, extending to rVaxAEs. GWV provide an opportunity to examine the relationship between their reported exposures and rAEs. Forty one GWV with GWI and 40 healthy controls reported exposure and rAEs to exposure, including for 14 vaccines. Individual and summed vaccine exposures, rVaxAEs, and reported Vaccine AE Propensity (summed rVaxAEs/summed vaccines exposures) were compared in cases vs. controls. Exposure-outcome assessments focused on GWV, using a multivariable regression with robust standard error. More designated vaccines were reported in cases than in controls: 9.0 (2.3) vs. 3.8 (2.3), p < 0.0001. The fraction of vaccines received that led to rAEs was ten-fold higher in cases: 0.24 (0.21), vs. 0.023 (0.081), p < 0.0001. Multivariable assessment confirmed that radiation and pesticides remained significant statistical predictors of reported Vaccine AE Propensity. Exposure tied to excess rVaxAEs in GWV may contribute to, or underlie, the reported link between rVaxAEs in GWV and later ill health.

Risk of disability for US army personnel vaccinated against anthrax, 1998-2005

To evaluate the potential for long-term or delayed onset health effects, we extended a previous cohort study of disability separation from the army associated with vaccination against anthrax. Analyses included stratified Cox proportional hazards and multiple logistic regression models. Forty-one percent of 1,001,546 soldiers received at least one anthrax vaccination; 5.21% were evaluated for disability. No consistent patterns or statistically significant differences in risk of disability evaluation, disability determination, or reason for disability were associated with anthrax vaccination. There was a dose-related trend in risk of disability for soldiers with 2 years' service, limited to those entering service in 2000 or later. Divergent patterns in risk suggest confounding by temporal or occupational risks of disability.

The cost-effectiveness of strategies to reduce mortality from an intentional release of aerosolized anthrax spores

BACKGROUND

Intentional exposures to aerosolized Bacillus anthracis spores have caused fatalities.

OBJECTIVE

To evaluate the cost-effectiveness of strategies to reduce mortality from future inhalational anthrax exposures.

METHODS

Computer cohort simulation of a 100,000-person single-site exposure (worst-case scenario) and a 100-person multiple-site exposure (resembling the recent US attack). For each scenario, universal vaccination and an emergency surveillance and response (ESR) system were compared with a default strategy that assumed eventual discovery of the exposure.

RESULTS

If an exposure was unlikely to occur or was small in scale, neither vaccination nor an ESR system was cost-effective. If an exposure was certain and large in scale, an ESR system was more cost-effective than vaccination ($73 v. $29,600 per life-year saved), and a rapid response saved more lives than improved surveillance.

CONCLUSIONS

Strategies to reduce deaths from anthrax attacks are cost-effective only if large exposures are certain. A faster response is more beneficial than enhanced surveillance.

A genomics-based approach to biodefence preparedness

Since October 2001, the United States has greatly expanded its commitment to biodefence-related research, with $1.75 billion earmarked for this activity in fiscal year 2003.

The goals of this accelerated research and development effort are to understand better the biology of potential bioterror agents and to use this information in the development of new diagnostics, antibiotics and vaccines to protect the world's population against bioterrorism.

Genomics, proteomics and bioinformatics approaches are considered to be key enabling technologies in the development of these new products.

Genome sequence data for all of the principal human pathogens, including most of the potential bioterror agents on the Center for Disease Control and Prevention (CDC) category A–C lists, are available in public databases and provide a new foundation for follow-up studies.

Comparative genomics approaches, together with large-scale methods for studying gene function, such as DNA microarrays, are providing insights into the molecular basis and evolution of pathogenicity, diversity within closely related isolates of the same pathogen and the molecular determinants of host–pathogen interactions.

Genomics-based approaches have already proven to be of great use in the identification of new targets for antimicrobial compounds and in the identification of new vaccine candidates.

Comparative genomics is also providing important information on the natural variability between closely related isolates that is aiding in the development of the new field of microbial forensics.

The anthrax letter attacks in October 2001, followed by the SARS outbreak in early 2003, dramatically illustrated our vulnerability to both deliberate and natural outbreaks of infectious disease. The availability of pathogen genome sequences and high-throughput methods for studying the biology of both pathogens and their hosts have provided new insights into the mechanisms of pathogenesis and host defence. As infectious disease research expands to include major bioterror agents, genomics-based approaches will provide one of the cornerstones of efforts to develop more accurate diagnostics, new therapeutics and vaccines, and further capabilities for microbial forensics.

Comprehensive systematic surveillance for adverse effects of anthrax vaccine adsorbed, US Armed Forces, 1998-2000

Routine vaccinations of US military personnel with Anthrax Vaccine Adsorbed began in 1998. To systematically identify clinical diagnoses reported more frequently after vaccination than before, all military personnel were retrospectively assigned to pre- or post-vaccination cohorts. Cohort assignments were based on vaccination statuses each day of the 3-year surveillance period. For each cohort, rates of hospitalizations and ambulatory visits for 843 specific diagnoses were calculated using data in a public health surveillance system. Compared to the pre-vaccination cohort, the post-vaccination cohort had statistically higher rates of hospitalizations for 17 diagnoses, of ambulatory visits for 34 diagnoses, and in both clinical settings for one diagnosis (malaria). After accounting for systematic differences in coding/reporting and residual confounding, the number and nature of clinical diagnoses more frequent after anthrax vaccination than before were consistent with expectations due to random variation. This surveillance suggests that Anthrax Vaccine Adsorbed has few, if any, clinically significant adverse effects.

Antibodies to squalene in recipients of anthrax vaccine

We previously reported that antibodies to squalene, an experimental vaccine adjuvant, are present in persons with symptoms consistent with Gulf War Syndrome (GWS) (P. B. Asa et al., Exp. Mol. Pathol 68, 196-197, 2000). The United States Department of Defense initiated the Anthrax Vaccine Immunization Program (AVIP) in 1997 to immunize 2.4 million military personnel. Because adverse reactions in vaccinated personnel were similar to symptoms of GWS, we tested AVIP participants for anti-squalene antibodies (ASA). In a pilot study, 6 of 6 vaccine recipients with GWS-like symptoms were positive for ASA. In a larger blinded study, only 32% (8/25) of AVIP personnel compared to 15.7% (3/19) of controls were positive (P > 0.05). Further analysis revealed that ASA were associated with specific lots of vaccine. The incidence of ASA in personnel in the blinded study receiving these lots was 47% (8/17) compared to an incidence of 0% (0/8; P < 0.025) of the AVIP participants receiving other lots of vaccine. Analysis of additional personnel revealed that in all but one case (19/20; 95%), ASA were restricted to personnel immunized with lots of vaccine known to contain squalene. Except for one symptomatic individual, positive clinical findings in 17 ASA-negative personnel were restricted to 4 individuals receiving vaccine from lots containing squalene. ASA were not present prior to vaccination in preimmunization sera available from 4 AVIP personnel. Three of these individuals became ASA positive after vaccination. These results suggest that the production of ASA in GWS patients is linked to the presence of squalene in certain lots of anthrax vaccine.

Structure of two iron-binding proteins from Bacillus anthracis

Bacillus anthracis is currently under intense investigation due to its primary importance as a human pathogen. Particularly important is the development of novel anti-anthrax vaccines, devoid of the current side effects. A novel class of immunogenic bacterial proteins consists of dodecamers homologous to the DNA-binding protein of Escherichia coli (Dps). Two Dps homologous genes are present in the B. anthracis genome. The crystal structures of these two proteins (Dlp-1 and Dlp-2) have been determined and are presented here. They are sphere-like proteins with an internal cavity. We also show that they act as ferritins and are thus involved in iron uptake and regulation, a fundamental function during bacterial growth.