Lecture 20: Viral Human Diseases Flashcards
1
Q
Chicken Pox
A
- Airborne viral disease
- humans serve as reservoir and source
- highly infectious
- acquired by droplet inhalation into respiratory system
- Varicella-zoster virus: ds DNA virus
- Vaccine prevents or shortens illness
2
Q
Shingles
A
- Varicella Zoster
-Individuals who recover from chickenpox have dormant viral DNA within cranial nerves - reactivated form of chickenpox
- Postherpetic neuralgia: Pain persists after vesicles have healed
- Treatment: antiviral drug
3
Q
Covid-19
A
- SARS-CoV-2 a causative virus
- RNA genome
- Key proteins: Spike, nucleocapsid, and proteases
- Mutations changed transmission rates, but NOT virulence
4
Q
Seasonal influenza
A
- Airborne Viral diseases
- orthomyxoviridae: influenza A, B and C virus
- acquired by inhalation or ingestion
- Viral particles adhere to host respiratory epithelium and initiate replication cycle
- Nucleocapsids released into cytosol
5
Q
Seasonal influenza- recombination
A
- recombination between RNA segments from human, swine, and avian strains lead to novel HA/NA combinations
6
Q
Measles
A
- Rubeola
- airborne viral diseases
- negative stranded, enveloped RN a virus in the genus Morbillivirus
- enters body through respiratory tract
- symptoms: cough, fever, headache, and conjunctivitis
- MMR vaccine
7
Q
Mumps
A
- caused by mumps virus (MuV)
- negative strand ssRNA, paramyxoviridae
- transmitted in saliva and respiratory droplets
- MMR vaccine
- Swelling and tenderness of salivary glands after infection
8
Q
Respiratory syncytial virus (RSv)
A
- Dangerous cause of lower respiratory infections
- negative strand RNA virus
- Spread by direct contact with respiratory secretions
- Symptoms; fever, cough, rhinitis and nasal congestion
- treatment: fluid replacement and fever reducers
9
Q
Rubella
A
- German measles
- enveloped positive strand RNA virus
- Spread through respiratory secretions
- red spot rash lasts 3 days and appears as immunity develops
- congenital rubella syndrome
- vaccine: MMR
10
Q
Congenital rubella syndrome
A
- Disease in the first trimester of pregnancy
- Can lead to fetal death, premature delivery, or congenital defects
11
Q
Smallpox
A
- airborne viral disease
- Transmitted by direct and fairly prolonged face to face contact
- symptoms; malaise, severe and high body aches, and high fever
- Only viral disease to be completely eradicated from the world
- no FDA approved
12
Q
Chikungunya
A
- arthropod vectored virus
- caused by a +ssRNA virus
- virus is a member of the Togaviridae
- acute infection manifests with joint pain, fever, headache, rash
13
Q
Dengue
A
- arthropod vectored virus
- Enveloped, +ssRNA virus
- Antibody-dependent enhancement
- Occurs when person has
previously been infected
with a different DENV
- Occurs when person has
- Four serotypes (DENV-1 through DENV-4)
14
Q
West Nile virus
A
- arthropod vectored virus
- Caused by a flavivirus,
+ssRNA virus - Transmitted to humans by Culex spp. mosquitoes that feed on infected birds
- No treatment, no vaccine
15
Q
Zika virus
A
- arthropod vectored viruses
- Enveloped +ssRNA virus in the Flaviviridae
- Transmitted by many species of Aedes mosquitoes
- Can be transmitted person to person through bodily fluids (that is, breast milk and semen)
- Causes birth defects like microcephaly with diminished brain tissue
16
Q
Acquired immune deficiency syndrome (AIDS)
A
- direct contact viral diseases
- caused by human immunodeficiency virus (HIV)
-HIV-1 is widespread in United States - HIV-2 is widespread in Africa
17
Q
HIV transmission & life cycle
A
- Transmitted when infected blood, semen, or vaginal secretions, or breast milk come in contact with an uninfected person’s mucous membranes
- Attaches to a host immune cell.
- Stains infecting macrophages
- Strains infecting T-cells
- RNA virus carries reverse transcriptase into host cell
18
Q
Later HIV Life Cycle
A
- Latency
- Can remain latent: asymptomatic
- Can direct synthesis of viral RNA -> synthesis of viral
particles -> virion assembled, released through budding
19
Q
Infectious mononucleosis
A
- direct contact viral disease
- Caused by Epstein–Barr
virus (EBV) - dsDNA genome
- highly prevalent
- infects B cells
- mouth to mouth contact
- rapid diagnostic tests available
20
Q
Human Papillomavirus (HPV)
A
- direct contact viral diseases
- highly prevalent
- transmitted sexually
- Some strains cause
anogenital warts, others
cause cancer of the cervix
in women
21
Q
Hepatitis
A
- direct contact viral disease
- Infection and inflammation of liver caused by 11 different viruses
- Hep B: Transmitted through body fluids and contaminated equipment. Vaccine available
-Hep C: Transmission via contaminated needles, from
mother to fetus, or through organ transplants. No
vaccine
22
Q
Hepatitis A + E
A
- food and water borne viruses
- *Hep A: Spread by fecal/oral contamination of food, drink, or shellfish
- Hep E: Spread by fecal/oral contamination of food or water
- Vaccine for Hep A, but not Hep E
23
Q
Polio
A
- food and water borne viruses
- caused by poliovirus
- Non-enveloped, +ssRNA enterovirus
- Multiplies in throat and small intestine
24
Q
Ebola virus disease (EVD)
A
- Zoonotic viral diseases
- Hemorrhagic fevers
- transmitted to humans through contact with body fluids
25
Marburg virus
- Zoonotic viral disease
- Hemorrhagic fevers
- Rare, severe fever that affects human and nonhuman primates
- Indigenous to Africa, fruit bat is reservoir host
- muliorgan dysfunction
26
Rabies
- Zoonotic viral diseases
- -ssRNA, bullet-shaped virus
- Primarily transmitted by bites of infected mammals
- Also transmitted by aerosols in caves where bats dwell or via scratches, abrasions, or mucous membranes with saliva of infected animals
