Arboviruses, Rabies Viruses Ebola Virus and HIV

Arboviruses properties

3 families: togaviruses, flaviviruses, and bunyaviruses
ssRNA

Arboviruses transmission

Bloodsucking vector

Arboviruses pathogenesis

Multiplies in both the host and the bloodsucking vector

Arboviruses clinical findings

One of three findings:
Encephalitis
Hemorrhagic fever
Fever with systemic symptoms (e.g. body aches)

Arboviruses disease

Eastern equine encephalitis
Yellow fever
Dengue
Zika

Rabies Virus properties

ssRNA (negative)
Bullet-shaped capsule

Rabies Virus transmission

Bite of rabid animal
(reservoir- bats, raccoons, dogs)

Rabies Virus pathogenesis

Virus multiples at the bite site and then moves into the CNS

Rabies Virus clinical findings

Delirium, seizures, paralysis

Rabies Virus disease

Rabies (encephalitis)

Ebola virus properties

Family: Filovirus
Long filamentous enveloped virus
ssRNA (negative)

Ebola virus transmission

Direct contact with blood, body fluids, and tissues of animals
(reservoir- fruit bats)

Ebola virus pathogenesis

Glycoproteins will kill endothelial cells and other proteins will inhibit the action of interferon
Hepatocytes are killed

Ebola virus clinical findings

Bleeding into skin, GI tract, and brain, DIC, thrombocytopenia

Ebola virus disease

Ebola hemorrhagic fever

Human Immunodeficiency Virus properties

Retrovirus (RNA → DNA → RNA)
ssRNA (positive)

Human Immunodeficiency Virus transmission

Sexual contact
Transfer of infected blood
Perinatal transmission

Human Immunodeficiency Virus pathogenesis

Infects and kills helper T cells (CD4 cells) which causes suppressed cell-mediated immunity

Human Immunodeficiency Virus clinical findings

3 stages
Acute: mono-like illness (fever, tiredness, sore throat, etc) with rash on trunk, arms, legs but not soles or palms
Middle (latent): no symptoms
Late: frequent opportunistic infections

Human Immunodeficiency Virus disease

Acquired immunodeficiency syndrome (AIDS)