Syndrome

Differential Diagnosis

Bioterrorism Threat Disease Description 

Initial laboratory & other diagnostic test results

Immediate public health & infection control actions

Acute Respiratory Distress with Fever

Dissecting aortic aneurysm, inhalational anthrax, pulmonary embolism

Inhalational Anthrax: Abrupt onset of fever; chest pain; respiratory distress without radiographic findings of pneumonia; no history of trauma or chronic disease; progression to shock and death within 24-36 hours

Chest x-ray with widened mediastinum; gram-positive bacilli in sputa or blood; definitive testing available through public health laboratory network.

Call Local Health Department. Alert laboratory to possibility of anthrax. Standard precautions.

Acute Respiratory Distress with Fever

Community acquired pneumonia, Hantavirus Pulmonary Syndrome, meningococcemia, pneumonic plague, rickettsiosis

Pneumonic Plague: Apparent severe community-acquired pneumonia but with hemoptysis, cyanosis, gastrointestinal symptoms, shock

Gram-negative bacilli or coccobacilli in sputa, blood or lymph node; safety-pin appearance with Wright or Giemsa stain; definitive testing available through public health laboratory network.

In addition to standard precautions, droplet precautions with a regular surgical mask. Call hospital infection control and Local Health Department. Ask family members/close contacts of patient to stay at the hospital (if already present) for public health interview/chemoprophylaxis; get detailed address and phone number information. Alert laboratory of possibility of plague.

Acute Respiratory Distress with Fever

Plague, Q fever, Staphylococcal enterotoxin B, phosgene, tularemia

Ricin (aerosolized): Acute onset of fever, chest pain and cough, progressing to respiratory distress and hypoxemia; not improved with antibiotics; death in 36-72 hours

Chest x-ray with pulmonary edema. Consult with Local Health Department regarding specimen collection and diagnostic testing procedures.

Call Local Health Department.  Standard precautions.

Acute Respiratory Distress with Fever

Influenza, adenovirus, mycoplasma

Staphylococcal enterotoxin B: Acute onset of fever, chills, headache, nonproductive cough and myalgia (influenza-like illness) with a NORMAL chest x-ray.

Primarily clinical diagnosis.  Consult with Local Health Department regarding specimen collection and diagnostic testing procedures.

Call Local Health Department.  Standard precautions.

Acute Rash with Fever

Varicella, disseminated herpes zoster, vaccinia, monkeypox, cowpox

Smallpox: Papular rash with fever that begins on the face and extremities and uniformly progresses to vesicles and pustules; headache, vomiting, back pain, and delirium common

Clinical with laboratory confirmation; vaccinated, gowned and gloved person obtains specimens (scabs or swabs of vesicular or pustular fluid).  Call public health immediately before obtaining specimen; definitive testing available through public health laboratory network.

Call hospital infection control immediately.  In addition to standard precautions, contact and airborne precautions required. Ask family members/close contacts of patient to stay at the hospital (if already present) for public health interview and vaccination; get detailed address and phone number information. Call Local Health Department immediately.

Acute Rash with Fever

Meningococcemia, malaria, typhus, leptospirosis, borreliosis, thrombotic thrombocytopenic purpura (TTP),  Hemolytic Uremic Syndrome (HUS)

Viral Hemorrhagic Fever (e.g., Ebola): Fever with mucous membrane bleeding, petechiae, throbocytopenia and hypotension in a patient without underlying malignancy

Definitive testing available through public health laboratory network--call public health immediately.

Call hospital infection control and Local Health Department.  Standard and contact precautions. Ask family members/close contacts of patient to stay at the hospital (if already present) for public health interview and follow-up; get detailed address and phone number information.

Neurologic Syndromes

Guillain-Barre Syndrome; myasthenia gravis; midbrain stroke; tick paralysis; Mg++ intoxication; organophosphate, carbon monoxide, paralytic shellfish, or belladonna-like alkaloid poisoning; polio; Eaton-Lambert myasthenic syndrome

Botulism: Acute bilateral descending flaccid paralysis beginning with cranial nerve palsies

CSF protein normal; EMG with repetitive nerve stimulation shows augmentation of muscle action potential;  toxin assays of serum, feces, or gastric aspirate available through public health laboratory network.

Request botulinum antitoxin from local/state health department; call Local Health Department. Standard precautions.

Neurologic Syndromes

Herpes simplex, post-infectious

Encephalitis (Venezuelan, Eastern, Western): Encephalopathy with fever and seizures and/or focal neurologic deficits.

Serologic testing available through public health laboratory network.

Call Local Health Department.  Standard precautions.

Influenza-like Illness

Numerous diseases, including Q Fever

Brucellosis: Irregular fever, chills, malaise, headache, weight loss, profound weakness and fatigue. Arthralgias,  sacroiliitis, paravertebral abscesses. Anorexia, nausea, vomiting, diarrhea, hepatosplenomegaly. May have cough and pleuritic chest pain.

Tiny, slow-growing, faintly-staining, gram-negative coccobacilli in blood or bone marrow culture.  Leukocyte count normal or low.  Anemia, thrombocytopenia possible. CXR nonspecific: normal, bronchopneumonia, abscesses, single or miliary nodules, enlarged hilar nodes, effusions. Serologic testing and culture available through public health laboratory network.

Notify laboratory if brucellosis suspected--microbiological testing should be done in a biological safety cabinet to prevent lab-acquired infection. Call Local Health Department.  Standard precautions.

Influenza-like Illness

Numerous diseases, including Q Fever

Tularemia (Typhoidal, Pneumonic): Fever, chills, rigors, headache, myalgias, coryza, sore throat initially; followed by weakness, anorexia, weight loss.  Substernal discomfort, dry cough if pneumonic disease.

Small, faintly-staining, slow-growing, gram-negative coccobacillus in smears or cultures of sputum, blood.  CXR may show infiltrate, hilar adenopathy, effusion. Definitive testing available through public health laboratory network.

Notify laboratory if tularemia suspected--microbiological testing should be done in a biological safety cabinet to prevent lab-acquired infection.  Call Local Health Department.  Standard precautions.

Blistering Syndromes

Mustard agents, Staphylococcal enterotoxin B

T2 Mycotoxin: Abrupt onset of mucocutaneous and airway irritation including skin (pain and blistering), eye (pain and tearing), gastrointestinal (bleeding, vomiting, and diarrhea), and airway (dyspnea and cough)

Consult with Local Health Department regarding specimen collection and diagnostic testing procedures.

Unlike other biological agents or biotoxins, trichothecene mycotoxins are dermally active and patients exposed to them should be decontaminated as soon as possible with soap and copious amounts of water.  Call Local Health Department for further instructions.