Week 9- Virus Flashcards
Gram positive
purple
gram negative
pink
What are the 2 main components that all viruses are composed of
-nucleic acid (dna or rna)
-Capsid (protein coat)
Why are viruses NOT considered cells?
-Acellular
-Don’t have cell components(cell membrane, walls organelles)
-Cant metabolize
-cant reproduce without host cell
-cant respond to environment
Where is an envelope located and how was it created?
Created from host cell
helps hide from immune system
What are the MAIN ways that viruses are pathogenic (able to cause disease)
1-Cells it infects-cytotoxic effect-where it kills cells
2-Our own immune response to the presence of virus in body
What “pathogenicity” factor do most
viruses have?
adhesion proteins
What is a “bacteriophage”?
virus that infects bacteria
dna and rna
dna-nuclus
rna-cytoplams
Briefly describe the 5 stages of the lytic cycle of viruses that infect humans
1-Attachment to host cell
2-entry-removes capsid if still attached
3-synthesis-creates components for virus
4-assembly-put components together
5-release of virus-kill cells
What is “latency” of an animal virus?
sitting in cells
dormant-
not causing infection
What will occur when the virus becomes lytic again?
causes infection again
Chicken pox caused by varicella zoster
childhood disease that causes fever, fatigue, headache and characteristic skin lesions—starts as red, bumpy rash and become fluid filled vesicles that eventually crust over.
Shingles caused by varicella zoster
Can initially cause fever, chills, headache and fatigue. Then causes: An itching, tingling or burning feeling in an area of your skin, redness on your skin in the affected area, raised rash in a small area of your skin (follows a dermatome), progresses into fluid-filled blisters that break open then scab over, mild to severe pain in the area of skin affected.
Roseola infantum caused by roseolvirus(human herpesvirus-6)
causes abrupt high fever followed by a rose colored rash on face, neck, trunk and thighs. Can also cause sore, throat, enlarged lymph nodes in children—can enter CNS and cause seizures
Smallpox caused by smallpox virus
causes fever, body aches, headache, chills, and, particularly, backache and infects internal organs – skin lesions go through stages (macules, papules, fluid filled then pus-filled) and cause characteristic scarring. “Minor” and “major” form/”major” form has 20% mortality)
Human papilloma infections caused by human papillomavirus (HPV
infects epithelial tissue or mucus membranes and causes different types of warts (seed, plantar, flat and genital);genital warts—can lead to cancer of cervix (there are 13 subspecies that are linked to cervical cancer)
Herpes infections caused by herpes simplex type I virus
causes itchy, painful cold sores/fever blisters and can also cause flu-like symptoms such as malaise, fever and muscle pain. Athletes can develop these lesions anywhere on their skin—common in wrestlers. (also whitlow—lesion on finger– and ocular disease). Can cause meningitis especially in infants.
Herpes infections caused by herpes simplex type Il virus
First outbreak can cause flu-like symptoms and then can cause itchy, painful genital lesions (can appear like blisters in genital area)– transmitted sexually. Can be transmitted to baby from mother during childbirth—this can be fatal
Hepatitis B infection caused by Hepatitis B virus
patients can be asymptomatic; can cause inflammation of the liver—causes jaundice (yellowing of skin and eyes) enlarged liver, abdominal distress, bleeding into skin and internal organs. Transmitted via sexual contact, blood or from mother to baby during childbirth
Mononucleosis caused by Epstein Barr virus
Virus infects B lymphocytes—caused sore throat, fever, extreme fatigue, muscle aches, swollen lymph nodes and spleen and liver, fatigue. Can also cause Burkitt’s Lymphoma (cancer) and Hodgkin’s lymphoma
Fifths disease caused by Parvovirus (B19 virus)
childhood disease has a distinctive rash that starts on cheeks (slapped cheek affect) and travels to thighs, buttocks and trunk (sunlight aggravates lesions). As rash progresses, earlier lesions fade. Also causes low fever, runny nose, sore throat, headache
Adenovirus infections caused by adenovirus
can cause common cold (sneezing, sore throat, cough, headache, malaise). Can also cause diarrhea and pink eye (conjunctivitis). Pink eye commonly transmitted via pool water not properly chlorinated. This virus is used in gene therapy.
Rubella caused by rubella virus
aka “German measles”. Usually a childhood disease. Upper respiratory infection that causes characteristic rash (flat, pink red spots) that lasts about 3 days. Can cross the placenta and cause severe congenital defects in baby.
