[Bioterrorism].

Biological terrorism is intentionally to use infectious substances for developing diseases or death in animals or humans, leading to disaster and panic in our community. Bioterrorism-associated diseases are mostly rare or eradicated infectious diseases, and recently, we do not have experience to make a clinical and laboratory diagnosis. In particular, these infectious diseases have incubation periods from infection to development of the disease. The staff working at public health institutions, including legal medicine, must be involved in as a first responder when bioterrorism would happen. The preparedness in general against bioterrorism and the bioterrorism-related diseases, such as anthrax, smallpox, viral hemorrhagic fever, tularemia, and botulinum toxin, important for us are described. Both medical knowledge of bioterrorism and the preparedness with training under simulation should be required in advance.

Vaccines against Francisella tularensis--past, present and future.

Francisella tularensis is a facultative intracellular bacterial pathogen capable of causing a spectrum of human diseases collectively called tularemia. The pathogen is highly infectious and some strains can cause rapidly lethal infection especially when inhaled. The latter were developed as biological weapons in the past and nowadays cause concern as potential bioterrorism agents. A live attenuated strain of the pathogen was developed more that 40 years ago and remains the sole prophylactic measure against the pathogen. Research to develop better live and subunit vaccines is under way. The former will require an understanding of the virulence factors of F. tularensis and a facile means of mutating them and the latter will require identification of the protective antigens of the pathogen. The current vaccine and its potential replacements are the focus of this review.

Anthrax, tularemia, plague, ebola or smallpox as agents of bioterrorism: recognition in the emergency room.

Bioterrorism has become a potential diagnostic consideration in infectious diseases. This article reviews the clinical presentation and differential diagnosis of potential bioterrorist agents when first presenting to the hospital in the emergency room setting. The characteristic clinical features of inhalation anthrax, tularemic pneumonia, plague pneumonia, including laboratory and radiographic finding, are discussed. Ebola vieus and smallpox are also discussed as potential bioterrorist-transmitted infections from the clinical and epidemiologic standpoint. In addition to the clinical features of the infectious diseases mentioned, the article discusses the infectious disease control and epidemiologic implications of these agents when employed as bioterrorist agents. The review concludes with suggestions for postexposure prophylaxis and therapy.

Bacterial pathogens as biological weapons and agents of bioterrorism.

Bacterial pathogens have been identified as agents that have been, or could be, used as weapons of biological warfare and/or biological terrorism. These agents are relatively easily obtained, prepared, and dispersed, either as weapons of mass destruction or for more limited terrorist attacks. Although phylogenetically diverse, these agents all have the potential for aerosol dissemination. Physicians in the United States and most of the developed world have never encountered most of these agents and the diseases they produce. Public health programs must be prepared, and individual primary care providers must be able to recognize, diagnose, treat, and prevent infection with these agents.

Tularemia.

Tularemia is a rare but potentially fatal disease that develops in numerous wild and domestic animals, including lagomorphs, rodents, cats, and humans. The disease occurs throughout much of the United States and should be considered in the differential diagnosis of acute febrile illness, particularly when risk factors such as contact with wild mammals or tick exposure are present. Veterinarians may be at increased risk of acquiring tularemia from contact with infected animals, but standard precautions should greatly reduce this risk. Outbreaks of tularemia warrant investigation, especially given the possibility of the use of F tularensis as an agent of bioterrorism.

[Tularemia as a biological weapon].

Tularemia is a zoonosis, caused by the Gram-negative bacterium, Francisella tularensis. The organism penetrates the human body through interrupted skin or mucous membranes, via animal contact or bites from ticks, deer-flies and mosquitoes. Contaminated aerosol and water are alternative modes of transmitting the germ through the respiratory and alimentary tracks. In light of its high infectivity in aerosol and its offensive occupation in the past, tularemia may appear in a biological warfare context. After an incubation period of 3-5 days, the disease begins with systemic symptoms, which abate, leaving a clinical picture, dominated by one of the listed patterns: ulceroglandular, typhoidal, glandular, occuloglandular, pharyngeal or pneumonic. Diagnosis and identification of the bacterium is difficult and even hazardous. Most diagnoses are established by serology which is positive in 50-70% of the patients after 2 weeks of illness, and in most of them by 4-8 weeks. The treatment of choice is streptomycin intra-muscular, or gentamicin intra-venous for 10-14 days. Prophylaxis may be achieved by tetracycline treatment, beginning up to 24 hours from exposure, for 2 weeks, or by a live attenuated, investigational vaccine. Nevertheless, post-exposure, or even better so, pre-exposure intervention is the most effective way of preventing the devastating results of the attack.

Rodents as potential couriers for bioterrorism agents.

Many pathogens that can cause major public health, economic, and social damage are relatively easily accessible and could be used as biological weapons. Wildlife is a natural reservoir for many potential bioterrorism agents, and, as history has shown, eliminating a pathogen that has dispersed among wild fauna can be extremely challenging. Since a number of wild rodent species live close to humans, rodents constitute a vector for pathogens to circulate among wildlife, domestic animals, and humans. This article reviews the possible consequences of a deliberate spread of rodentborne pathogens. It is relatively easy to infect wild rodents with certain pathogens or to release infected rodents, and the action would be difficult to trace. Rodents can also function as reservoirs for diseases that have been spread during a bioterrorism attack and cause recurring disease outbreaks. As rats and mice are common in both urban and rural settlements, deliberately released rodentborne infections have the capacity to spread very rapidly. The majority of pathogens that are listed as potential agents of bioterrorism by the Centers for Disease Control and Prevention and the National Institute of Allergy and Infectious Diseases exploit rodents as vectors or reservoirs. In addition to zoonotic diseases, deliberately released rodentborne epizootics can have serious economic consequences for society, for example, in the area of international trade restrictions. The ability to rapidly detect introduced diseases and effectively communicate with the public in crisis situations enables a quick response and is essential for successful and cost-effective disease control.

Missed sentinel case of naturally occurring pneumonic tularemia outbreak: lessons for detection of bioterrorism.

BACKGROUND: Family physicians are likely to care for patients that have been exposed to diseases associated with bioterrorism. Persons with seemingly nondescript initial disease symptoms could be harbingers of a larger outbreak, whether naturally occurring or purposefully created. METHODS: We report a missed sentinel case of pneumonic tularemia associated with a naturally occurring outbreak. The patient's initial clinical symptoms and signs were nondescript, and the diagnosis was recognized by subsequent blood tests. The medical literature was searched using the key words "tularemia," "bioterrorism," "index of suspicion," and "sentinel case." RESULTS AND CONCLUSIONS: Being alert to possible unexpected causes of a pneumonic summer illness in a patient with associated weight loss might have led to an earlier diagnosis of this sentinel case tularemia and its association with the subsequent outbreak. Individual patients are likely to visit a physician's office after a purposeful bioterrorism event. Greater efforts must be made to increase awareness in all primary care physicians who might see patients exposed to a bioterrorism illness.