Management of Hemorrhagic Fever Viruses: Intervention of Natural and Synthetic Products

Background: Viral hemorrhagic fevers (VHFs) are a group of clinical syndromes caused by several different RNA virus families, including several members of the arenavirus, bunyavirus, filovirus, and flavivirus families. VHFs have high mortality rates, and they have been associated with vascular permeability, malaise, fever, variable degrees of hemorrhage, reduced plasma volume, and coagulation abnormalities. To treat such conditions, antigen-presenting cells target dysregulated immune reactions and productive infections. Monocytes and macrophages produce inflammatory cytokines that damage adaptive immunity, while infected dendritic cells fail to mature correctly, compromising adaptive immunity. Inflammation and uncontrolled virus replication are associated with vascular leakage and coagulopathy. Objective: VHF infects both humans and animals and if not treated, causes hemorrhagic manifestations and lethal platelet dysfunction. Besides pharmacological and immunological solutions, the intervention of natural products for VHF management is of great interest. In this review, we gathered current data about the effectiveness of natural products for VHF management. Methods: Data were extracted from Scopus, Google Scholar, PubMed, and Cochrane library in terms of clinical and animal studies published in English between 1981 to February 2022. Results: Several plants from diverse families and species were identified with antiviral activity against VHF. The combination of botanical therapeutics and multitarget synergistic therapeutic effects is now the widely accepted explanation for the treatment of VHF. Most of these herbal therapeutics have shown promising immunomodulatory effects in vivo and in vitro VHF models. They can probably modulate the immune system in VHF-infected subjects mainly by interfering with certain inflammatory mediators involved in various infectious diseases. Conclusion: Natural, in particular, herbal sources can be valuable for the management of various VHFs and their related complications.