The positive-sense, single-stranded RNA is around 10,862 nucleotides long and has a single open reading frame encoding a polyprotein.Host proteases cut this polyprotein into three structural (C, prM, E) and seven nonstructural proteins (NS1, NS2A, NS2B, NS3, NS4A, NS4B, NS5); the enumeration corresponds to the arrangement of the protein coding genes in the genome. Minimal yellow fever virus (YFV) 3UTR region is required for stalling of the host 5-3 exonuclease XRN1. The UTR contains PKS3 pseudoknot structure, which serves as a molecular signal to stall the exonuclease and is the only viral requirement for subgenomic flavivirus RNA (sfRNA) production. The sfRNAs are a result of incomplete degradation of the viral genome by the exonuclease and are important for viral pathogenicity. Yellow fever belongs to the group of hemorrhagic fevers.The viruses infect, amongst others, monocytes, macrophages, Schwann cells, and dendritic cells. They attach to the cell surfaces via specific receptors and are taken up by an endosomal vesicle. Inside the endosome, the decreased pH induces the fusion of the endosomal membrane with the virus envelope. The capsid enters the cytosol, decays, and releases the genome. Receptor binding, as well as membrane fusion, are catalyzed by the protein E, which changes its conformation at low pH, causing a rearrangement of the 90 homodimers to 60 homotrimers.After entering the host cell, the viral genome is replicated in the rough endoplasmic reticulum (ER) and in the so-called vesicle packets.
These programs have largely been unsuccessful because they were unable to break the sylvatic cycle involving wild primates. With few countries establishing regular vaccination programs, measures to fight yellow fever have been neglected, making the future spread of the virus more likely. Research
In the hamster model of yellow fever, early administration of the antiviral ribavirin is an effective treatment of many pathological features of the disease. Ribavirin treatment during the first five days after virus infection improved survival rates, reduced tissue damage in the liver and spleen, prevented hepatocellular steatosis, and normalised levels of alanine aminotransferase, a liver damage marker. The mechanism of action of ribavirin in reducing liver pathology in yellow fever virus infection may be similar to its activity in treatment of hepatitis C, a related virus. Because ribavirin had failed to improve survival in a virulent rhesus model of yellow fever infection, it had been previously discounted as a possible therapy. Infection was reduced in mosquitoes with the wMel strain of Wolbachia.Yellow fever has been researched by several countries as a potential biological weapon. Notes
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External links

Yellow fever at Curlie
Finlay CJ (January 2012). "The Mosquito Hypothetically Considered as the Transmitting Agent of Yellow Fever". MEDICC Review. 14 (1): 56–59. doi:10.37757/MR2012V14.N1.10. PMID 34503309. "U.S. Army Yellow Fever Commission." Claude Moore Health Sciences Library, University of Virginia
"Yellow fever virus". NCBI Taxonomy Browser. 11089.