Brucella is a dangerous, highly virulent organism and the aerosols are highly infectious. It is the MOST common cause of laboratory-associated bacterial infections. Laboratory acquired cases have occurred by aerosol generating procedures, direct skin contact with cultures, and by sniffing cultures. It should NOT be manipulated on an open bench.Catalase: Brucella is catalase positive. Catalase testing MUST be performed with extreme caution in a biosafety cabinet (BSC) due to the creation of aerosols. Oxidase: PositiveBeta-lactamase: PositiveUrease: PositiveXV factors: Not required for growth (satellite phenomenon with S. aureus is negative)Serological testing: Often used because so difficult to grow. An acute and convalescent phase specimen should be collected 21 days apart.
Toxin Comment Most Likely Means of Dissemination Primary Route of Entry General Signs and Symptoms Laboratory Testing Botulism toxin: Gram stained image of C. botulinum courtesy of CDC Produced by Clostridium botulinum Could be purified and used in a bioterrorist event to contaminate food or aerosolized to cause disease Aerosol Food contamination Inhalation Ingestion Difficulty speaking or swallowing Blurred or double vision Drooping eyelids (ptosis) Dilated pupils Dry mouth, decreased gag reflex Weakening of the reflexes (hyporeflexia) Abnormal sensations such as numbness, tingling, and progressive arm or leg weakness Flaccid paralysis Culture, anaerobic Digoxigen-labeled IgG ELISA to detect A, B, E, and F toxins Mouse Bioassay for all toxin types and to confirm DIG ELISA Ricin toxin: Extracted from Castor beans Inhibits protein synthesis Causes death approximately 72 hours after initial exposure As an aerosol Inhalation Fever Cough Chest tightness Dyspnea Cyanosis Gastroenteritis Necrosis Antibody detection in clinical specimens Clinical testing not performed unless known exposure has occurred
VirusMost Likely Means of Dissemination Primary Route of EntryGeneral Signs and SymptomsLaboratory TestingSmallpox: Image courtesy of CDCAs an aerosol Inhalation High fever with extreme lethargySevere headache, backache, and abdominal painRash that starts as red bumps but quickly develops into small, itchy blisters Consult local APHL prior to sample collectionShell vial and DFA Monoclonal IFAMolecular tests Viral Hemorrhagic Fevers (Ebola, Marburg, Lassa, and Argentine): SolidLiquidAerosol AbsorptionInhalationIngestion Vary by type of viral hemorrhagic fever (VHF), but initial signs and symptoms often include: Marked feverFatigueDizzinessMuscle aches, loss of strength, and exhaustionSevere cases of VHF often show signs of bleeding under the skin, within internal organs, or from body orifices like the mouth, eyes, or ears Enzyme-linked immunosorbent assay (ELISA)Polymerase chain reaction (PCR)Viral culture
|Location Where Organisms Naturally Occur, Disease Produced, and Mode of Transmission, continued:|
Brucella species: Brucella is distributed in nature worldwide and found in domesticated and wild animals, such as cattle, sheep, and pigs. Infection with Brucella species, known as brucellosis, is caused in humans by exposure to infected animal fluids or food products. This includes ingesting non-pasteurized dairy products, such as milk or cheese, inhaling aerosols, and skin contact with the fluids of infected animals. Brucellosis poses an increased risk of occupational exposure to laboratory, veterinary, and slaughterhouse workers. Brucella is the most commonly reported laboratory-associated bacterial infection.Burkholderia mallei and B. pseudomallei: Most Burkholderia are found in soil, but B. mallei is only found in mammals. B.mallei is the causative agent for Glanders which primarily affects animals such as donkeys, mules, and horses. Horses, the organism's natural host, are highly susceptible to infection. Human infection is rare and usually occurs in people working with infected animals or laboratory workers handling the organism. The organism is endemic in Africa, Asia, the Middle East, and Central and South America, and usually enters via the eyes, nose, mouth, abrasions or cuts in the skin, or through inhalation. B. pseudomallei is found in soil and water and can accidentally infect animals, plants, and rarely humans. It is the causative agent of melioidosis, which is endemic in areas of southeast Asia, Taiwan, and northern Australia. The organism generally enters through cuts in the skin, ingestion of contaminated water, or by inhalation of an aerosol.
|Category A Agents: Reasons Why They May be Used to Create Public Health Emergencies|
Anthrax (B. anthracis): Inhalation of anthrax spores is virtually 100% fatal Spores can remain infectious for decadesBotulism: Most lethal toxic agent known Toxin could be used to contaminate food supplies Can be aerosolized in enclosed areasPneumonic Plague (Y. pestis): Aerosolized in large amounts Short incubation period, usually in less than three days, and invariably fatal without early and effective antimicrobial therapy Untreated, fatality rate exceeds 90% Disease is spread from direct exposure to respiratory droplets of infected humansSmallpox: Highly contagious and deliberate spread by aerosol is extremely infectious Mass panic would be createdTularemia (F. tularensis): Highly contagious and easily spread An aerosol containing as few as 25 organisms can cause infection Easily penetrates the smallest breaks in the skinViral Hemorrhagic Fever: Causes internal and external bleeding and would likely cause great panic and easily spread by direct contact with body fluids or respiratory droplets Outbreak due to bioterrorist attack could lead to mass illness and death