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State Research Institute for Plague Control, Rostov-on-Don In the second part of the review aspects of intraspecies differentiation of the plague agent are discussed. Special emphasis is placed on the necessity of more precise definition of taxonomic position of plague agent isolates considering genotypical characteristics, data on their selective virulence, and evolutionary origin of the genus Yersinia.

The use of immunochromatographic indicatory elements based on antibody conjugates and colloidal gold was suggested to detect cells and the antigens of extremely dangerous infectious pathogens. The specificity and specific activity (sensitivity) of the mentioned elements were studied on vaccinal strains of plague, anthrax, and tularemia pathogens. The researchers studied a possibility to increase the sensitivity of immunochromatographic analysis using computed scanning and Reflecom, a specialized digital video recorder of immunochromatogramms. The study demonstrated that the use of electronic devices to record immunochromatogramms increased the sensitivity to microbial cells and antigens 1.5 to 2 times vs. visual registration and simplified documentation of the results.

The performance of a single-tube nested-PCR (STNPCR) technique was evaluated for plague diagnosis in comparison to conventional (one step) and two step nested PCR (NPCR). Assays were carried out with primers targeting the gene caf1 that encodes the Yersinia pestis F1 antigen. For STNPCR inner primers were immobilized onto the inside of the microtube caps and after the first amplification they were eluted by inversion of the tube. This procedure avoids opening the tube, reducing the risks of false-positive results by cross-contamination. The immobilized primers are stable for several months at -20 degrees C, thus, the tubes can be prepared beforehand and stored until use. STNPCR was more sensitive than conventional PCR, and less sensitive than NPCR. This drawback is compensated by a lower risk of cross-contamination. The experiments with infected animals showed that NPCR and STNPCR were able to produce positive results in all samples tested, despite contamination with other organisms. In contrast, conventional PCR yielded positive results in a smaller number of samples. Three out of 62 culture-negative rodents from plague areas, were positive by STNPCR. In conclusion, the PCR approaches evaluated, particularly NPCR and STNPCR have potential to be used as alternative tools in epidemiological surveys of plague. Furthermore, as the results can be obtained quickly (less than 24 hour), these techniques could be useful in emergency situations in which the rapidity in diagnosis is essential for adoption of immediate measures of control.

Despite the clinical-epidemiological features of plague, numerous suspected cases in Brazilian outbreaks have been discarded because of negative results from the hemagglutination test for antibodies against the Yersinia pestis F1 antigen. The transcendence of plague justifies studying whether such results are due to unresponsiveness to F1, and whether other Y. pestis proteins might be recognized in suspect serum. These would therefore be candidates to be alternative diagnostic targets to the F1 antigen. Thus, strains of Y. pestis and Y. pseudotuberculosis, a recombinant YopH protein and the F1 antigen were used to analyze serum from patients and immune serum from rabbits. F1 and YopH were not recognized by HA-negative human serum and no major protein common to all the human and rabbit serum samples was identified. This allows the conclusion that suspected cases must be subjected to more rigorous clinical-laboratory evaluation, with strengthening of epidemiological investigations in the search of other etiologies.

Mortality from plague is high if not treated with the proper antibiotics within 18-24 hours after onset of symptoms. The process of antibiotic susceptibility determination of Yersinia pestis isolated from blood samples may extend from 4 to more than 7 days, since the in vitro growth is very slow. To accelerate this process, we developed an enrichment protocol as well as a non-standard yet reliable method for rapid antibiotic susceptibility analysis of Y. pestis from blood cultures using flow cytometry technology. This rapid method is applicable to blood cultures containing low levels of Y. pestis.

A focal outbreak of pneumonic plague occurred in a hamlet of village Hatkoti, district Shimla, Himachal Pradesh in the first fortnight of February, 2002. A total of 16 cases with 4 deaths were reported. Diagnosis of plague was confirmed by the laboratory in 10 (63%) cases. Y. pestis was isolated from clinical samples of 3 cases and confirmed by bacteriophage lysis. Molecular tests confirmed the presence of Y. pestis specific pla and F1 genes in 4 cases; DNA fingerprinting had identity with the known sequence of plague bacilli. Paired samples from 5 cases showed more than 4 fold rise and 1 case showed more than 4 fold fall in antibodies against F1 antigen of Y. pestis. The present communication emphasises that timely and systematic laboratory investigations give confirmatory diagnosis in shortest possible time which forms the backbone of the outbreak control in a timely fashion and prevents confusion and controversy.

As part of the broader "science of surge" consensus initiative sponsored by Academic Emergency Medicine, this report addresses the issues of detection and situational awareness as they relate to surge in the practice of emergency medicine. The purpose of this report, and the breakout group that contributed to its content, was to provide emergency physicians and other stakeholders in the emergency medicine community a sense of direction as they plan, prepare for, and respond to surge in their practice.

Bioterrorism is defined by the intentional or threatened of microorganisms or toxins derived from living organisms to cause death or diseases in humans, animals or plants on which we depend. The other major point is to generate fear in the population. More than 180 pathogens have been reported to be potential agents for bioterrorism. The following is an overview of several agents that could be involved in a biological attack.

Plague is a zoonotic disease caused by the bacterium Yersinia pestis. In 2006, a total of 13 human plague cases have been reported among residents of four states: New Mexico (seven cases), Colorado (three cases), California (two cases), and Texas (one case). This is the largest number of cases reported in a single year in the United States since 1994. Dates of illness onset ranged from February 16 to August 14; two (15%) cases were fatal. The median age of patients was 43 years (range: 13-79 years); eight (62%) patients were female. Five (38%) patients had primary septicemic plague, and the remaining eight (62%) had bubonic plague. Two (15%) patients developed secondary plague pneumonia, leading to administration of antibiotic prophylaxis to their health-care providers. This report summarizes six of the 13 cases, highlighting the severity and diverse clinical presentations of plague and underscoring the need for prompt diagnosis and treatment when plague is suspected.

A plague episode in Surat in 1994, and its spread to other cities in India, lasted only a little over 2 weeks, but it created an unprecedented panic that had global repercussions. At first, the Surat hospital doctors could not diagnose the disease, but when they did, immediate intervention, in the form of preventation and treatment (administration of antibodies) prevented the disease from spreading beyond Surat, Delhi, Calcutta, Bombay and their vicinities. Fewer than 1,200 people were diagnosed with plague. A DNA-based study in 2000 decisively concluded that the Surat episode was a plague, but the Indian isolates were genetically more heterogeneous compared to others in the world.

The painting "St. Rochus with an angel" by Quinten Massys in the Alte Pinakothek in Munich was utilized for a teledermatological quiz. First, only a detail of the plague bubo on the thigh was sent electronically to all physicians in our department. The answers were correct descriptions, but the interpretations quite heterogeneous. In a second set, the full painting together with the hint- Pinakothek - was given. Now the number of descriptively correct diagnoses was high; one resident knew the name of the featured individual and his diagnosis. This example demonstrates one problem with teledermatology - when viewing a clinical picture, relevant additional information is frequently essential in order to make a correct diagnosis. In addition, this presentation of saint physicians and hospitals, the holy Rochus, better known to those who are under his protection.

The public and clinicians have long-held beliefs that pneumonic plague is highly contagious; inappropriate alarm and panic have occurred during outbreaks. We investigated communicability in a naturally occurring pneumonic plague cluster. We defined a probable pneumonic plague case as an acute-onset respiratory illness with bloody sputum during December 2004 in Kango Subcounty, Uganda. A definite case was a probable case with laboratory evidence of Yersinia pestis infection. The cluster (1 definite and 3 probable cases) consisted of 2 concurrent index patient-caregiver pairs. Direct fluorescent antibody microscopy and polymerase chain reaction testing on the only surviving patient's sputum verified plague infection. Both index patients transmitted pneumonic plague to only 1 caregiver each, despite 23 additional untreated close contacts (attack rate 8%). Person-to-person transmission was compatible with transmission by respiratory droplets, rather than aerosols, and only a few close contacts, all within droplet range, became ill.

From October to November 2001, the inhalational and cutaneous anthrax cases that occurred in the U.S. underscored the importance of recognizing the clinical and pathological features of infectious agents that can be used in acts of terrorism. Early confirmation of bio-terrorist acts can only be performed by making organism-specific diagnosis of cases with clinical and pathologic syndromes that could be caused by possible bioterrorism weapons. Recognition and diagnosis of these cases is central to establish adequate responses. This review will examine the events that occurred during the anthrax bio-terrorist attack with specific emphasis on the role of pathology and immunohistochemistry and will describe the histopathologic features of category A bioterrorism agents (anthrax, plague, tularemia, botulism, smallpox, and viral hemorrhagic fevers).

Between late January and early February 1997, an outbreak of plague, associated with cervical lymphadenopathy and fever, occurred in the Jordanian village of Azraq ad-Druze, which lies about 50 km west of the border with Saudi Arabia. The 12 cases who presented at hospital were initially assumed to have tularaemia, and all were successfully treated with gentamicin. When, however, their sera were tested for evidence of Yersinia pestis or Francisella tularensis infection (using haemagglutination, enzyme immuno-assays for specific IgM or the F1 antigen of Y. pestis, and micro-agglutination tests), all 12 were found to have anti-Y. pestis IgM. Three dogs shot near the Saudi Arabian border were also found seropositive for antibodies against Y. pestis. Eleven of the 12 patients reported that, 2-4 days before their symptoms appeared, they had eaten the meat cut from the carcass of the same camel, either raw (10 cases) or cooked (one case). All 12 patients were diagnosed as cases of pharyngeal plague (the first cases of plague reported in Jordan for more than 80 years), caused by Y. pestis that most had acquired when they ate raw meat from a camel that was infected with the pathogen.

Anthrax, plague, Q fever, and tularemia are all potential inhalational bioterrorism agents. The pulmonary manifestations of these agents can be readily confused with each other as well as other more common diseases such as influenza and atypical pneumonia. This article reviews the threat potential, microbiology, pathogenesis, clinical features, diagnosis, and treatment of each of these agents and highlights the similarities and differences between their pulmonary presentations.

Background: Early recognition of a terrorist attack with biologic agents will rely on physician diagnosis. Physicians' ability to diagnose and care for patients presenting after a bioterror event is unknown. The role of online case-based didactics to measure and improve knowledge in the diagnosis and treatment of these patients is unknown., Methods: A multicenter online educational intervention was completed by 631 physicians at 30 internal medicine residency programs in 16 states and Washington, DC, between July 1, 2003, and June 10, 2004. Participants completed a pretest, assessing ability to diagnose and manage potential cases of smallpox, anthrax, botulism, and plague. A didactic module reviewing diagnosis and management of these diseases was then completed, followed by a posttest. Pretest performance measured baseline knowledge. Posttest performance compared with pretest performance measured effectiveness of the educational intervention. Results were compared based on year of training and geographic location of the residency program., Results: Correct diagnoses of diseases due to bioterrorism agents were as follows: smallpox, 50.7%; anthrax, 70.5%; botulism, 49.6%; and plague, 16.3% (average, 46.8%). Correct diagnosis averaged 79.0% after completing the didactic module (P<.001). Correct management of smallpox was 14.6%; anthrax, 17.0%; botulism, 60.2%; and plague, 9.7% (average, 25.4%). Correct management averaged 79.1% after completing the didactic module (P<.001). Performance did not differ based on year of training (P = .54) or geographic location (P = .64). Attending physicians performed better than residents (P<.001)., Conclusions: Physician diagnosis and management of diseases caused by bioterrorism agents is poor. An online didactic module may improve diagnosis and management of diseases caused by these agents.

Bacillus anthracis, Francicella tularensis, Yersinia pestis, Burkholderia pseudomallei and Brucella melitensis are the bacteria most often mentioned in connection with possible biological terrorist acts. It is known that these microorganisms can be cultured and weaponised for such a purpose. This survey provides examples of the use of diagnostic methods for those microorganisms, further detailed in relation to establishing a national center for biological preparedness in Denmark.

Objective: To study an epidemic of human lung plague fulminant from September to October, 2004 in Nangqian county, Qinghai province., Methods: Cases were diagnosed through data from epidemiological, clinical, bacteriological, serological and autopsy studies., Results: 14 patients were identified, ending up with 6 deaths and 8 cured. The first case was diagnosed as primary pesticemia late progressed to lung plague. 4 cases were transformed from pesticemia out of 13, leaving the 9 cases as primary lung plague. Situation was under complete control through routinely handling the plague focus., Conclusion: The first case was bitten by the infected fleas which parasitized the marmota preyed on a dog but later these fleas were brought into the tent by the dog. The others cases were infected through droplets or dust. Programs on monitoring and controling the amount of marmotas and fleas should to be strengthened to prevent the epidemics of plague in the area.

The experimentally obtained antigenic complex isolated by extraction in the gradient surfactants from live and acetone-dried bacteria of the capsule-free vaccine strain EV76 of a plague microbe that had lost its ability to synthesize the diagnostic species-specific capsular antigen F1 was investigated. The antigenic complex fraction V (FV) was obtained after the fifth stage of extraction at a concentration of 1.28% of surfactants and after additional purification. The thermostable FV was found to consist mainly of protein. The protein having a molecular mass of about 43 kD predominates in the fraction. The latter is nontoxic for albino mice and antigenic. It forms a precipitate with commercial antiplague serum antibodies. FV antigenic sensitization of tanned sheep red blood cells gave rise to a diagnostic agent that specifically reacted with an antiplague serum rather than with heterologous sera against enterobacteria. The sera immunized with FV specifically reacted in the JDJFR with all the strains of the pathogen of plague irrespective of the temperature of their cultivation, including "fraction-free", which did not interact with a diagnosticum on F1. The animal sera immunized with capsule-free plague microbial strain reacted only with a FV-erythrocytic diagnosticum and they did not interact with F1 antigen-sensitized red blood cells. The erythrocytic FV diagnosticum was tested in ABNR with 130 typical and atypical plague microbial strains and with 133 strains of heterologous bacteria of different species of the family Enterobacteriaceae. The FV diagnosticum identified all the variants of a plague microbe, while the F1 diagnosticum revealed only its capsular variants. Among the heterologous bacteria, some strains of the closely related pathogen of pseudotuberculosis in those who were in the R form, rather than S form, positively reacted. The use of FV identified 2 groups of hybridomas obtained after immunization of albino mice with the capsule-free variant of a plague microbe. Some hybridomas reacted only with plague bacteria while others did with two above pathogens. The authors substantiate the expediency of using FV, its components, and obtained monoclonal plague pathogen antibodies to improve antiplague diagnosticums with an activity spectrum that exceeds that of the existing commercial F1 antigen-based diagnosticums. They also discuss the lines of further studies.

The severe 1994 plague outbreaks in Surat and Beed drew attention to plague as a continuing source of both natural and potentially manmade disease. This article written a decade later reviews various aspects of Plague not only as a disease but also as an infectious disaster.

The post September 11th anthrax attacks demonstrated just how vulnerable we are to biologic attack. In the first days of the attack, there was confusion and miscommunication. Patients presented to emergency rooms and to their primary care physicians with severe pneumonia. Days passed and a person died before the cause of pneumonia was recognized as Bacillus anthracis. In a biologic attack, the prompt recognition of the biologic agent is key to the outcome for both individual patients and potentially even our society. The three category A bacterial agents, anthrax, tularemia, and plague, can all present as a necrotizing pneumonia. If an attack occurred during flu season when there is already an increase in pneumonia, most physicians will initially have a great deal of difficulty determining that these cases are different. Yet, considering the nature of the world today every physician must be suspicious that the next pneumonia he or she sees could be the index case of anthrax, tularemia, or plague. The challenge for the clinician evaluating a patient presenting with the presumptive diagnosis of community-acquired pneumonia is differentiating between the various possible etiologies that can cause this clinical picture. Each of these three class A agents has it own microbiologic and clinical characteristics. They are discussed here.

Monoclonal antibodies (MAbs) were generated against the recombinant plasminogen activator (Pla) protein of Yersinia pestis. These MAbs detected Pla in all the 18 isolates of Y. pestis obtained from the sputum of pneumonic plague patients and from the liver and spleen of rodents from plague-affected areas of India during 1994-1995 as well as in seven of the eight isolates obtained from rodents in the surveillance regions of Hosur and Palmner in India during 1998 by simple dot-ELISA. In immunoblotting, the MAbs reacted with the Pla antigen only in Y. pestis isolates at 37 and 35kDa region. These monoclonal antibodies, being strictly specific, can be used for detecting Y. pestis isolates that are Fraction 1 antigen-negative. Also, the radiolabelled pla fragment hybridized specifically to the representative DNA samples of Y. pestis isolates.

Nuclear, biological and chemical warfare have in recent times been responsible for an increasing number of otherwise rare dermatoses. Many nations are now maintaining overt and clandestine stockpiles of such arsenal. With increasing terrorist threats, these agents of mass destruction pose a risk to the civilian population. Nuclear and chemical attacks manifest immediately while biological attacks manifest later. Chemical and biological attacks pose a significant risk to the attending medical personnel. The large scale of anticipated casualties in the event of such an occurrence would need the expertise of all physicians, including dermatologists, both military and civilian. Dermatologists are uniquely qualified in this respect. This article aims at presenting a review of the cutaneous manifestations in nuclear, chemical and biological warfare and their management.

In the United States, there is currently a major gap in the diagnostic capabilities with regard to plague. To address this, we developed an antigen capture assay using an essential virulence factor secreted by Yersinia spp., LcrV, as the target antigen. We generated anti-LcrV monoclonal antibodies (MAbs) and screened them for the ability to bind bacterially secreted native Yersinia pestis LcrV. Anti-LcrV MAb 19.31 was used as a capture antibody, and biotinylated MAb 40.1 was used for detection. The detection limit of this highly sensitive Yersinia LcrV capture enzyme-linked immunosorbent assay is 0.1 ng/ml. The assay detected LcrV from human sputum and blood samples treated with concentrations as low as 0.5 ng/ml of bacterially secreted native Y. pestis LcrV. This assay could be used as a tool to help confirm the diagnosis of plague in patients presenting with pneumonia.

Yersinia pestis appears to be a good candidate agent for a bioterrorist attack. The use of an aerosolised form of this agent could cause an explosive outbreak of primary plague pneumonia. The bacteria could be used also to infect the rodent population and then spread to humans. Most of the therapeutic guidelines suggest using gentamicin or streptomycin as first line therapy with ciprofloxacin as optional treatment. Persons who come in contact with patients with pneumonic plague should receive antibiotic prophylaxis with doxycycline or ciprofloxacin for 7 days. Prevention of human-to-human transmission via patients with plague pneumonia can be achieved by implementing standard isolation procedures until at least 4 days of antibiotic treatment have been administered. For the other clinical types of the disease, patients should be isolated for the first 48 hours after the initiation of treatment.

Yersinia pestis, the causative agent of plague, is an aerobic, non-motile, gram-negative bacillus belonging to the family Enterobacteriacea. It is a zoonotic infection transmitted to humans via the bite of a flea. Three clinical forms of human plague exist: bubonic, pneumonic, and septicemic. Many important virulence factors associated with this organism are responsible for its extreme pathogenicity and high mortality rates. The bubonic form of plague is usually not transmitted human to human but the pneumonic form is--through inhalation of contaminated aerosol droplets. The pneumonic plague would be the form most likely implicated in the event of an intentional attack. Inhalation of aerosols can cause devastating consequences resulting in many casualties. Unless antibiotics are administered within 24 hours of the initial symptoms, death is inevitable. Its potential for use as a biological weapon is of major concern to public health officials.

Technological innovations in the detection and identification of microorganisms using molecular techniques such as polymerase chain reaction (PCR) have ushered in a new era with respect to diagnostic microbiology. PCR using universal or specific primers followed by identification of amplified product, mainly by sequencing, has enabled the rapid identification of cultured or uncultured bacteria. Thus, PCR may allow quick diagnosis of infections caused by fastidious pathogens for which culture could be extremely difficult. However, several pitfalls, such as false positives, have been observed with PCR, underlining the necessity to interpret the results obtained with caution. At present, certain improvements in the molecular genetic methods may be helpful for the diagnosis of infectious diseases. Indeed, the recent development of bacterial genome sequencing has provided an important source of potential targets for PCR, allowing rational choice of primers for diagnosis and genotyping. In addition, the development of new techniques such as real-time PCR offers several advantages in comparison to conventional PCR, including speed, simplicity, reproducibility, quantitative capability and low risk of contamination. Herein, we review the general principles of PCR-based diagnosis and molecular genetic methods for the diagnosis of several hard-to-culture bacteria, such as Rickettsia spp., Ehrlichia spp., Coxiella burnetii, Bartonella spp., Tropheryma whipplei and Yersinia pestis.

Host-pathogen interactions result in protein expression changes within both the host and the pathogen. Here, results from proteomic characterization of host response following exposure to Yersinia pestis, the causative agent of plague, and to two near neighbors, Yersinia pseudotuberculosis and Yersinia enterocolitica, are reported. Human monocyte-like cells were chosen as a model for macrophage immune response to pathogen exposure. Two-dimensional electrophoresis followed by mass spectrometry was used to identify host proteins with differential expression following exposure to these three closely related Yersinia species. This comparative proteomic characterization of host response clearly shows that host protein expression patterns are distinct for the different pathogen exposures, and contributes to further understanding of Y. pestis virulence and host defense mechanisms. This work also lays the foundation for future studies aimed at defining biomarkers for presymptomatic detection of plague.

Plague is a disease that has been present for thousands of years and described since the earliest medical accounts. It occurs today worldwide, and may present in a variety of clinical forms. Bubonic disease, pneumonic plague, and septicemic plague are seen in addition to a number of other less common manifestations. As an agent of bioterrorism,Yersinia pestis could pose an extreme threat if released in the appropriate form and in the appropriate environment. Presumptive diagnosis may be made with readily available techniques, but laboratory handling of specimens requires special care. When there is a strong suspicion of plague, treatment should be instituted immediately, as delaying therapy will result in increased morbidity and mortality.

Recent events of war, terrorist attacks, and mail-borne anthrax exposure have produced increasing awareness of potential bioterrorism attacks in the United States and other parts of the world. Physicians and healthcare personnel play a key role in identifying potential bioterrorist attacks. Early recognition and preparedness for bioterrorism-associated illnesses is especially important for neurologists because most bioterrorism agents can directly or indirectly affect the nervous system. This article reviews the neurologic manifestations, diagnosis, and treatments of syndromes caused by potential bioterrorism agents, as well as the potential side effects of vaccines against some of these agents.

Serodiagnosis of plague is very useful for its retrospective confirmation and for epidemiologic studies in humans and in rodents, since rats constitute the main natural reservoir of Yersinia pestis. We have developed a rapid test for the detection of IgG antibodies to fraction 1 (F1) based on immunochromatography and protein A to detect both human and rat IgG. When tested with reference human sera (35 positive and 37 negative), this assay showed a sensitivity of 94.3% and a specificity of 89.2%. When Rattus rattus and R. norvegicus reference sera (22 positive and 24 negative) were used, the sensitivity was 100% and the specificity was 91.7%. This simple serodiagnostic tool is of great potential value in the surveillance of plague. As far as we know, this test is the first of its kind designed for diagnosis of both humans and animals.

The use of micro-organisms as agents of biological warfare is considered inevitable for several reasons, including ease of production and dispersion, delayed onset of symptoms, ability to cause high rates of morbidity and mortality and difficulty in diagnosis. Therefore, the clinical presentation and pathogenesis of the organisms posing the highest threat (variola major, Bacillus anthracis, Yersinia pestis, Clostridium botulinum toxin, Francisella tularensis, filoviruses, arenaviruses and Brucella species), as well as the available diagnostic techniques and treatments for such infections, will be reviewed in this article. Due to the necessity of rapid identification and diagnosis, molecular techniques have been the ongoing focus of current research. Consequently, the molecular diagnostic techniques that have recently been developed for the diseases associated with these agents will be emphasized.

Pneumonic plague, a disease caused by the bacterium Yersinia pestis, is a rare disease in the United States and carries a high mortality. Health care professionals in the United States are not familiar with the clinical presentation and diagnosis of plague pneumonia. The wide prevalence of the bacterium in different parts of the world, its high virulence, and its ability to spread by aerosolization makes it a potential agent of biological warfare in the hands of terrorists. This review focuses on the prevalence, pathogenesis immunity, clinical manifestations, diagnosis, treatment, and prevention of plague pneumonia, with particular emphasis on the plague bacillus as an agent of biological warfare. Based on available information, we discuss measures that need to be undertaken by health care personnel, public health personnel, and epidemiologists in the event of such an attack.

On November 1, 2002, a married couple traveled from Santa Fe County, New Mexico, to New York City (NYC), where they both became ill with fever and unilateral inguinal adenopathy; bubonic plague (Yersinia pestis) was diagnosed subsequently. This report summarizes the clinical and public health investigation of these cases and underscores the importance of rapid diagnosis and communication among health-care providers, public health agencies, and the public when patients seek medical attention for an illness that might be caused by an agent of terrorism.