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Published on: July 10, 2019
Chapare Hemorrhagic Fever and Virus Detection in Rodents in Bolivia in 2019
Roxana Loayza Mafayle1, Maria E Morales-Betoulle1, Carla Romero1
1From Centro Nacional de Enfermedades Tropicales, Santa Cruz de la Sierra (R.L.M., C.E.A.A., C.A.A., M.C.Z., A.D.A., N.M.L., A.-M.M., F.L.M.A., J.R.G., S.S.M.), and Unidad de Epidemiología (C.R., G.A.D.L.V., A.M.R., J.T.M.G.), Unidad de Gestión de Riesgos en Salud Ambiental, Emergencias y Desastres (A.J.C.P.), and Instituto Nacional de Laboratorios de Salud "Dr. Néstor Morales Villazón" (R.S.B.), Ministerio de Salud, the Pan American Health Organization (A.A.), Hospital Obrero No. 1, Caja Nacional de Salud (A.S.), Hospital Militar Central, Hospital Municipal Boliviano Holandés (K.M.T.C.), and Hospital de Clínicas (A.V.-C.), La Paz - all in Bolivia; the Centers for Disease Control and Prevention, Atlanta (M.E.M.-B., C.M.C., S.W., B.R.A., M.J.C., B.-R.E., C.G., J.C.G., A.J., J.D.K., A.L., J.H.M., S.T.N., K.P., T. Sealy, T. Shoemaker, C.F.S., A.T., J.S.T., J.M.M.); Instituto Nacional de Enfermedades Virales Humanas "Dr. Julio I. Maiztegui," Pergamino, Argentina (J.B., J.G.); the Pan American Health Organization, Washington, D.C. (J.M.-R.); and Universidade Federal do Rio Grande do Norte, Natal, Brazil (K.L.).
Background:
In June 2019, the Bolivian Ministry of Health reported a cluster of cases of hemorrhagic fever that started in the municipality of Caranavi and expanded to La Paz. The cause of these cases was unknown.
Methods:
We obtained samples for next-generation sequencing and virus isolation. Human and rodent specimens were tested by means of virus-specific real-time quantitative reverse-transcriptase-polymerase-chain-reaction assays, next-generation sequencing, and virus isolation.
Results:
Nine cases of hemorrhagic fever were identified; four of the patients with this illness died. The etiologic agent was identified as Mammarenavirus Chapare mammarenavirus, or Chapare virus (CHAPV), which causes Chapare hemorrhagic fever (CHHF). Probable nosocomial transmission among health care workers was identified. Some patients with CHHF had neurologic manifestations, and those who survived had a prolonged recovery period. CHAPV RNA was detected in a variety of human body fluids (including blood; urine; nasopharyngeal, oropharyngeal, and bronchoalveolar-lavage fluid; conjunctiva; and semen) and in specimens obtained from captured small-eared pygmy rice rats (Oligoryzomys microtis). In survivors of CHHF, viral RNA was detected up to 170 days after symptom onset; CHAPV was isolated from a semen sample obtained 86 days after symptom onset.
Conclusions:
M. Chapare mammarenavirus was identified as the etiologic agent of CHHF. Both spillover from a zoonotic reservoir and possible person-to-person transmission were identified. This virus was detected in a rodent species, O. microtis. (Funded by the Bolivian Ministry of Health and others.).

