Prevention of anthrax with vaccine is successful and vaccination is recommended if you are at risk of developing anthrax. Prevention of anthrax is required in risky population because if untreated anthrax is almost 100% fatal for inhalational anthrax and more than 20% fatal for cutaneous anthrax. Inhalational anthrax is the form most likely to be responsible for death in a setting of a bioterrorist attack. Patients with inhalational anthrax are not contagious and do not require special isolation.
The first successful anthrax vaccine was developed by Louis Pasteur in 1881 for animals. At present anthrax vaccine is produced from the cell-free culture supernatant of an attenuated, nonencapsulated strain of B. anthracis (known as anthrax vaccine adsorbed or AVA) and is licensed for human use.
As an alternative to AVA, clinical trials for safety in humans and efficacy in animals are currently under way to evaluate the role of recombinant protective antigen of B. anthracis toxins. In preventing the development of clinical disease and death in a post-exposure setting in non-human primates a 2 week trial course of AVA + ciprofloxacin was found to be superior to ciprofloxacin alone.
Chemoprophylaxis: The current recommendation for postexposure prophylaxis is 60 days of antibiotics (Ciprofloxacin or doxycycline); it would be better to include immunization with anthrax vaccine (AVA) if available. There is a potential for B. anthracis to engineer and express penicillin resistance, and due to that, the empirical regimen of antibiotics of choice in this setting is either ciprofloxacin or doxycycline.
The prevention of bioterrorist attacks is the responsibility of the Govt. and not discussed here. But support of the general public is must for the Govt. to prevent bioterrorist attacks successfully.
Anthrax can be easily and successfully treated if diagnosed promptly and treatment instituted early and immediately after diagnosis. Anthrax is in the news because of the recent microbial bioterrorist attacks in the United States. Modern science has revealed methods and unleashed a devil of deliberately spreading anthrax and other diseases in ways not appreciated by our ancestors. The combination of basic scientific research, good medical practice, and constant vigil will be required by the public and the Govt. to defend against such attacks.
Clinical features of anthrax: the clinical feature depends on the route of entry of the organism mainly gastrointestinal, cutaneous, and inhalational. Symptoms include cutaneous lesions of papule to eschar (begins as a papule following the introduction of spores through an opening in the skin. This papule then evolves to a painless vesicle followed by the development of a coal-black, necrotic eschar). If the anthrax is due to inhalation the symptoms are fever, malaise, chest pain, abdominal discomfort etc. On chest x-ray there is pleural effusion and widened mediastinum.
Diagnosis of anthrax: Anthrax is diagnosed with laboratory tests like PCR (polymerase chain reaction) test, Wright stain of blood peripheral smear, Gram staining and blood culture of the organism causing anthrax (Bacillus anthracis a gram-positive, nonmotile, spore-forming rod that is found in soil and predominantly causes disease in herbivores like cattle, goats, and sheep).
Treatment of anthrax: penicillin (amoxicillin), ciprofloxacin, and doxycycline are the currently licensed antibiotics for treatment of anthrax. But clindamycin and rifampin can also used as part of treatment regimens and they are also being used to treat anthrax. Treatment is started with penicillin (amoxicillin), ciprofloxacin, and doxycycline till sensitivity results are known and once sensitivity results are known treatment is changed if required.
Post exposure treatment: It is done with Ciprofloxacin, 500 mg, orally twice a day for 60 days or doxycycline 100 mg orally twice a day for 60 days or amoxicillin (likely to be effective if strain penicillin sensitive) 500 mg, orally thrice a day for 60 days.
Treatment of active anthrax: Ciprofloxacin, 500 mg intravenously 12 hourly or doxycycline 100 mg intravenously 12 hourly plus Clindamycin, 900 mg IV 8 hourly and/or rifampin, 300 mg IV 12 hourly. Switch to oral route when stable for60 days total treatment including intravenous route.