Arthropod borne arbo viral diseases
Sponsored Links
This presentation is the property of its rightful owner.
1 / 64

Arthropod-Borne (Arbo) Viral Diseases PowerPoint PPT Presentation


  • 109 Views
  • Uploaded on
  • Presentation posted in: General

Arthropod-Borne (Arbo) Viral Diseases

Download Presentation

Arthropod-Borne (Arbo) Viral Diseases

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Arthropod-Borne (Arbo) Viral Diseases

The arthropod-borne viruses, or arboviruses, are a group of infectious agents that are transmitted by blood-sucking arthropods from one vertebrate host to another. They can multiply in the tissues of the arthropod without evidence of disease or damage. The vector acquires a lifelong infection through the ingestion of blood from a viremic vertebrate. All arboviruses have an RNA genome, and most have a lipid-containing envelope and consequently are inactivated by ether or sodium deoxycholate.


Current taxonomic status of some arboviruses


Current taxonomic status of some arboviruses


Current taxonomic status of some arboviruses


Sindbis virus


Structures of Alphaviruses


Principal medically important alphaviruses


The scheme of Alphavirus replication


Pathogenesis of alphaviruses


FIGURE Alphavirus transmission. Virus abbreviations: Chik, chickungunya; RR, Ross River; May, Mayaro; ONN, O'nyong-nyong; SIN, Sindbis; EEE, eastern equine encephalitis; VEE, Venezuelan equine encephalitis.


Rubellaviruses

Rubella (German measles) is a common mild disease characterized by a rash. It affects children and adolescents worldwide and can also affect young adults. When rubella virus infects susceptible women early in pregnancy, it may be transmitted to the fetus and may cause birth defects. Therefore, accurate diagnosis is critical in pregnancy. The rubella virus is a member of the genus Rubivirus in the family Togaviridae.


Rubella virus


Rash


FIGURE. Clinical findings, virus shedding, and serologic response

in postnatally acquired rubella.


Abnormalities Associated with Congenital Rubella Syndrome


Abnormalities Associated with Congenital Rubella Syndrome


Cataract


Glaucoma


Structure of Flaviviruses


Flavivirus


Tick-born encephalitis virus


Tick-born encephalitis virus


Figure 5. The scheme of Flavivirus replication


Virions are formed in perinuclear regions of the cytoplasm in association with Golgi or smooth membranes (Figure 6). Virions appear within cytoplasmic vacuoles and appear to exit the cell as vacuoles fuse with the plasma membrane. Unlike alphaviruses, no evidence of budding has been seen in flavivirus-infected cells, and the mechanisms of virion assembly and release remain obscure.

FIGURE 6. Morphogenesis of flaviviruses


Principal medically important flaviviruses


Principal medically important flaviviruses


Principal medically important flaviviruses


Human infection with both mosquito-borne and tick-borne flaviviruses is initiated by deposition of virus through the skin via the saliva of an infected arthropod (Fig 7).

Figure 7. Pathogenesis of flaviviruses.


Tick


Yellow fever virus


Yellow fever


Dengue fever virus


Dengue fever


Bunyaviridae is a family of arthropod-borne or rodent-borne, spherical, enveloped RNA viruses. Bunyaviruses are responsible for a number of febrile diseases in humans and other vertebrates. They have either a rodent host or an arthropod vector and a vertebrate host.


Rift Valley Fever virus


Human diseases Caused by Viruses of the Family Bunyaviridae


Human diseases Caused by Viruses of the Family Bunyaviridae


Human diseases Caused by Viruses of the Family Bunyaviridae


Human diseases Caused by Viruses of the Family Bunyaviridae


Human diseases Caused by Viruses of the Family Bunyaviridae


Human diseases Caused by Viruses of the Family Bunyaviridae


FIGURE 3. Pathogenesis of bunyavirus infections. Humans are dead-end hosts of most bunyaviruses; however, the blood of Crimean-Congo hemorrhagic fever patients may be highly infectious.


FIGURE 5. La Crosse encephalitis transmission cycle


Signs of Crimean-Congo Hemorrhagic Fever


Clinics of Hataan virus infection


  • Login