Definition: Chapare hemorrhagic fever (CHHF) is caused by Chapare virus, a single-strand RNA virus of the Arenaviridae family. Chapare virus is certainly zoonotic, or animal-borne. The limited clinical information about CHHF comes from a small, poorly described cluster of hemorrhagic fever cases in rural Bolivia. A single fatal case yielded the only clinical description and blood specimen to date.
Symptoms and Treatment: The symptoms of CHHF, as reported in the only described patient, resemble those of other South American hemorrhagic fevers, such as Argentine HF or Bolivian HF. The incubation period is unknown, but for Argentine hemorrhagic fever (AHF) is 6 to 16 days. The CHHF clinical course included: Fever, headache, articulation and muscle pain, vomiting. These symptoms were followed by deterioration with multiple hemorrhagic signs. The only described CHHF patient died 14 days after onset of symptoms. Supportive therapy is important in CHHF. This includes: maintenance of hydration, management of shock, sedation, pain relief, usual precautions for patients with bleeding disorders, transfusions. Use of convalescent plasma therapy for treatment of AHF reduces mortality significantly and anecdotal evidence shows that the antiviral drug ribavirin may also hold promise for treating AHF. Ribavirin has also been considered for preventing development of disease in people exposed to other arenaviruses.
Statistics: In Spain statistical analysis were resulted as there are several reasons to justify a replication-competent, “live” vaccine as an attractive approach to control LF: (i) cell-mediated immunity (CMI) plays the major role in LF patient recovery and in protection; (ii) a live vaccine provides the most effective natural pathway to process and present protective antigens to MHC molecules; (iii) epidemiological observations in LF endemic areas of West Africa provide evidence that a single (survived) exposure will induce long-term protection against disease; (iv) a vaccine candidate formulated to contain both LASV NP and GP antigens will induce a broad cross-reactivity and a large pool of CD4+ memory T cells against all phylogenetic groups of LASV; (v) a single-shot immunization approach is a crucial for population of remote rural areas of West Africa, which has a very limited medical infrastructure and where implementation of prime-boosting immunization is not practical.