Re-Emerging Human Viral Hemorrhagic Fevers: A Review

Abstract

The explosive introduction of Chikungunya in the Caribbean and imported cases in the United States, the rapid spread of Ebola in West Africa, the clusters of birth defects linked to an epidemic of Zika virus in the Americas, and the increasing endemic spread in parts of West Africa and recent imported cases of Lassa fever in the United Kingdom and Germany illustrate how quickly local outbreaks of infectious diseases can become threats to international public health. Unfortunately, with the exception of a few, there are no drugs or vaccines available for treatment or prevention of re-emerging human viral hemorrhagic infections, thus, surveillance remains the best approach for the early detection of outbreaks. Although, molecular diagnostics continues to evolve very rapidly, and its impact in the diagnosis of infectious viral diseases is undeniable, multiple challenges still remain for the widespread use of cost-effective, validated, and commercially available molecular tools. In this review, we briefly describe the epidemiology and global expansion of selected re-emerging hemorrhagic fever viruses in recent years, then focus on the clinical features and the laboratory testing for the diseases. In particular, we reflect on new learnings during recent outbreak investigations, discuss ongoing research and development priorities and identify further interventions needed for effective control and prevention of these re-emerging viral diseases.