The symptoms of Lujo hemorrhagic fever, as described in the five patients in the original cluster outbreak, resemble those of severe Lassa Fever. After an incubation period of 7 to 13 days, the clinical course started by a non-specific febrile illness accompanied by headache and muscle pain.
The disease increases in severity, with:
Bleeding was not a prominent feature during the illness.
In the fatal cases (4/5 patients), a transient improvement was followed by:
Death occurred 10 to 13 days after onset.
Low blood platelets, low white blood cell count (at the onset, rising later on) and elevated liver function values were present in all patients.
Since Arenaviruses may enter the fetus through infection of the mother, and anectodal evidence suggests that infected pregnant women may suffer miscarriages, it is reasonable to assume that both infection of the fetus and miscarriage may be associated with Lujo infection in the mother.