Presentation of Lassa fever varies. Common early symptoms are gradual onset of fever, malaise, headache, and abdominal pain. Other symptoms are conjunctivitis, facial swelling, sore throat, non-productive cough, retrosternal pain, nausea, vomiting, diarrhea, back pain, and myalgia. Respiratory rate, temperature, pulse rate are increased and blood pressure decreased. Neurological symptoms may also occur, including hearing loss, tremors, and encephalitis.
Severe infections produce hemorrhagic manifestations, pleural effusions, and shock.
Pregnant women are more likely to die than are others. See full discussion. Treatment is supportive and also includes ribavirin as discussed below. Incubation of Ebola and Marburg HFs ranges from 3-16 days. Both Ebola and Marburg HFs are characterized by sudden onset of fever, chills, severe headache, and myalgia.