Week 9- Virus

Question 1

Gram positive

Answer 1

purple

Question 2

gram negative

Answer 2

pink

Question 3

What are the 2 main components that all viruses are composed of

Answer 3

-nucleic acid (dna or rna)

-Capsid (protein coat)

Question 4

Why are viruses NOT considered cells?

Answer 4

-Acellular

-Don’t have cell components(cell membrane, walls organelles)

-Cant metabolize

-cant reproduce without host cell

-cant respond to environment

Question 5

Where is an envelope located and how was it created?

Answer 5

Created from host cell

helps hide from immune system

Question 6

What are the MAIN ways that viruses are pathogenic (able to cause disease)

Answer 6

1-Cells it infects-cytotoxic effect-where it kills cells

2-Our own immune response to the presence of virus in body

Question 7

What “pathogenicity” factor do most
viruses have?

Answer 7

adhesion proteins

Question 8

What is a “bacteriophage”?

Answer 8

virus that infects bacteria

Question 9

dna and rna

Answer 9

dna-nuclus

rna-cytoplams

Question 10

Briefly describe the 5 stages of the lytic cycle of viruses that infect humans

Answer 10

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

Question 11

What is “latency” of an animal virus?

Answer 11

sitting in cells

dormant-

not causing infection

Question 12

What will occur when the virus becomes lytic again?

Answer 12

causes infection again

Question 13

Chicken pox caused by varicella zoster

Answer 13

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.

Question 14

Shingles caused by varicella zoster

Answer 14

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.

Question 15

Roseola infantum caused by roseolvirus(human herpesvirus-6)

Answer 15

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

Question 16

Smallpox caused by smallpox virus

Answer 16

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)

Question 17

Human papilloma infections caused by human papillomavirus (HPV

Answer 17

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)

Question 18

Herpes infections caused by herpes simplex type I virus

Answer 18

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.

Question 19

Herpes infections caused by herpes simplex type Il virus

Answer 19

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

Question 20

Hepatitis B infection caused by Hepatitis B virus

Answer 20

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

Question 21

Mononucleosis caused by Epstein Barr virus

Answer 21

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

Question 22

Fifths disease caused by Parvovirus (B19 virus)

Answer 22

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

Question 23

Adenovirus infections caused by adenovirus

Answer 23

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.

Question 24

Rubella caused by rubella virus

Answer 24

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.

Question 25

Rotavirus infection caused by rotavirus

Answer 25

most common cause of severe watery diarrhea (fluid/electrolyte loss) leading to dehydration in children and causing hospitalization due to severe dehydration. There is a vaccine available. Also have vomiting, abdominal pain and fever. It can affect adults as well

Question 26

Coronavirus infections caused by SARS Co-V and SARS Co-V2

Answer 26

different types of this virus cause respiratory infections such Severe Acute Respiratory Syndrome (fever, cough, difficulty breathing, respiratory distress) and Covid-19 infection (fever, cough, shortness of breath, loss of taste or smell, sore throat, headache, fatigue, respiratory distress). These infections can be severe and lead to death due to respiratory failure

Question 27

Respiratory syncytial virus (RSV) infection caused by

Answer 27

causes infection in lower respiratory tract especially in infants and young children. Virus causes formation of syncytia in lungs (cells fuse together) as well as can cause the smaller airways to fill with mucus, fibrin and dead cells. Can be fatal. Typically shows cold like symptoms in healthy children and adults.

Question 28

Norovirus infection caused by norovirus

Answer 28

most common cause of viral acute gastroenteritis in U.S.—very contagious. Symptoms include diarrhea, vomiting, stomach pain and nausea. Can affect people of all ages. Severe dehydration can occur.

Question 29

Poliomyelitis caused by poliovirus

Answer 29

enterovirus (transmitted oral-fecal route) that can invade cells of spinal cord and brain producing paralysis in limbs or respiratory muscles (MOST infections are asymptomatic). Resolves in 6 to 24 months but can get a syndrome years after infection (deterioration of the originally affected muscles)

Question 30

Mumps caused by mumps virus

Answer 30

childhood infections that affects respiratory system—causes fever and sore throat and swollen parotid glands. Can cause sterility in boys due to inflammation of testes

Question 31

Measles caused by measles virus

Answer 31

contagious childhood disease that affects respiratory tract and then spreads via lymph and blood to body; causes fever, sore throat, headache, dry cough and conjunctivitis. Koplik spots (rash inside mouth) appear and then a “patchy” rash occurs on head and body

Question 32

Influenza caused by Influenza A or B virus

Answer 32

causes abrupt respiratory symptoms— fever, myalgia (body aches), headache, malaise, nonproductive cough, sore throat, and rhinitis—can lead to pneumonia and death

Question 33

AIDS caused by HIV (human immunodeficiency virus)

Answer 33

This virus infects helper T cells—original symptoms are fever, fatigue, weight loss. The patient is severely immunocompromised so will be prone to MANY opportunistic infections (bacterial, fungal, viral)and viral tumors which can be fatal

Question 34

Rabies caused by Rabies virus

Answer 34

zoonotic disease; initial signs are pain and itching at site of infection (animal bite), fever, headache and malaise. If not treated the virus travels to central nervous system to infect neurons then causes neurological symptoms (hydrophobia, seizures, disorientation, hallucinations and paralysis) that can lead to death

Question 35

Hepatitis C virus

Answer 35

chronic liver disease that can cause severe liver damage over time and can lead to liver cancer—transmitted via needles, organ transplants and sexual activity