Alphaviruses are infectious agents that replicate in humans and many animals; this viral genus includes Chikungunya virus, Semliki Forest virus and Sindbis virus. Alphaviruses are transmitted by arthropods, mai
通读全文,尤其是第一段的“Infectious disease is all around us. Disease-causing agents, such as viruses, usually have specific targets. Some viruses affect only humans; other viruses live in or affect only animals. Problems start when animal viruses are able to infect people as well, a process...
Viruses are microscopic infectious agents that contain genetic material, eitherDNAorRNA, and must invade a host in order to multiply. Predominantly, viruses are known for causing disease, as they've triggered widespread outbreaks of illness and death throughout human history. Recent examples of virus...
Newly emerging viruses are not the only ones to plague humans, however. Many viruses that have been known for a long time continue to cause widespread problems. Respiratory syncytial virus, as an example, is a major cause of pneumonia in infants. Despite much effort, it has not yet been po...
Viruses are microscopic infectious agents, and up to 10,000 smaller than mostbacteria. They are the most common biological structure on our planet, being more numerous than animals, plants, fungi, parasites and bacteria together. Viral shapes ...
However, these fortifications are not impenetrable e.g., the enteric virus Hepatitis A has the ability to survive and penetrate the body through the gastrointestinal tract (Campbell et al., 1999). In addition, the epithelial barrier of the intestine is embedded with mucous-producing goblet cells...
Viruses are infectious agents that consist of genetic material wrapped in a protein coat. Viruses can only replicate (copy and grow in number) when they are inside the host cell of an infected organism. This is because they need the cellular machinery of the host to replicate successfully and...
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are different species, such as cuckoos, would not. When applied to viruses, this narrower definition would still classify a range of cases as cheating, such as defective interfering genomes, and point-mutation mutants such as D51 and PhiH2. However, according to the narrower definition, other...
VOLUME 2 PART III – Infectious Diseases and Their Etiologic Agents 132 – Introduction to Viruses and Viral DiseasesChappellDermodyChapell J, Dermody T. Introduction to viruses and viral diseases. In: Mandell, Douglas, and Bennett's principles and practice of in- fectious dis...