Some patients may develop shortness of breath and retrosternal chest pain. Fever may last 2-5 days and cough may persist for up to 4 weeks. Ingestion of the toxin leads to acute salivation, nausea, and vomiting followed by abdominal cramps and diarrhea. Fever and respiratory involvement are not seen in foodborne SEB intoxication. Higher exposure can lead to septic shock and death if left untreated.
Physical examination is often unremarkable.
Postural hypotension may be present, particularly with ingestion of SEB, due to fluid loss. Conjunctivitis may be seen, although it was not present in any of 9 individuals accidentally exposed in a laboratory. Rales may be present. An epidemic of influenza, adenovirus, parainfluenza, or mycoplasma could cause fever, nonproductive cough, myalgias, and headache occurring in large numbers of people in a short time. Early clinical manifestations of SEB may be similar to those of inhalation anthrax, tularemia, plague, or Q fever, but the rapid progression of respiratory signs and symptoms to a stable state distinguishes SEB intoxication.