Viruses Flashcards

Question

papillomavirus (HPV) | features / diseases

Answer 1

``` DNA non-enveloped chronic 100 types of virus (30 genital, 70 skin) papillomas: benign skin tumor, genital warts cervical/ penis cancers ```

Answer 2

slow replication hard to grow in lab lysogeny with integration inhibits checkpoint proteins in cell cycle HPV 16/18 inactivate tumor suppressor genes (p53, Rb), increase risk of mutations increase in number and size of lesions increases risk of cancer 80% of cases are single small lesions

Answer 3

skin to skin contact | genital contact

Answer 4

vaccine (3 doses) antivirals liquid nitrogen for lesions

Answer 5

RNA enveloped genome in 8 segments hemagglutinin (16) and neuraminidase (9) in envelope acute animals and humans respiratory infection only (A- most common, humans, can cause pandemic B- limited epidemics in humans C- mostly in animals) seasonal flu pandemic flu (every 20 years, killed 4% world pop in 1918)

Answer 6

replicates in nucleus lytic in lungs antigenic shift: avian flu + regular flu -> new deadly virus host immune response worse than infection

Answer 7

airborne droplets

Answer 8

vaccine (2 A, 1 B isolates) | tamiflu (some A's resistant)

Answer 9

RNA enveloped non-segmented genome paramyxovirus mumps- parotid gland swelling

Answer 10

upper respiratory tract first viremia to parotid, testes/ ovaries, pancreas

Answer 11

respiratory droplets | highest spread in winter

Answer 12

live attenuated vaccine lifelong immunity no treatment

Answer 13

``` RNA enveloped non-segmented genome single stranded RNA (negative) paramyxovirus measles ```

Answer 14

lytic in immune cells viremia to skin starts in upper respiratory tract rash caused by cytotoxic T clls

Answer 15

airborne droplets 30 million cases/year worldwide causes epidemics

Answer 16

live attenuated vaccine lifelong immunity no treatment

Answer 17

RNA enveloped single stranded RNA (positive) togavirus rubella and congenital rubella syndrome

Answer 18

airborne droplets transplacenta eliminated from US

Answer 19

lytic in nasopharynx and lymph nodes | spreads via blood to organs and skin

Answer 20

live attenuated vaccine lifelong immunity no treatment

Answer 21

``` lentivirus (retrovirus) single stranded RNA has GP120 and GP41 glycoproteins to regulate inflammation = GP120 attacks CD4 cells = CP31 attacks CCR5, CXCR4 diploid virus HIV-1, HIV-2 ```

Answer 22

``` infects WBCs, destroys helper T cells lysogeny- hides in host chromosome integration steps: 1. virus fuses, enters cell 2. reverse transcriptase converts RNA to DNA 3. DNA becomes double stranded 4. DNA carried into nucleus by integrase (lysogeny) 5. copies make viral RNA and mRNA 6. protease breaks DNA to make proteins 7. viral assembly and budding healthy: 120-1500 CD4 cells/ul AIDS: 200-500 CD4 cells/ul acute retroviral syndrome: 3 months asymptomatic: 7-10 years, decrease 50 CD4 cells/ year AIDS: several years until death ```

Answer 23

unprotected sex (receptive and anal are riskier) other STDs increases risk sharing needles transplacental

Answer 24

condoms | reverse transcriptase or protease inhibitors in cocktail of drugs

Answer 25

RNA non-enveloped gastroenteritis most common cause of gastroenteritis in children

Answer 26

lytic in intestinal tissue causes lesions in intestines diarrhea

Answer 27

fecal oral (water)

Answer 28

vaccine (esp for kids in developing countries) personal hygiene water treatment self-resolving

Answer 29

RNA non-enveloped gastroenteritis ("stomach flu") most common viral gastroenteritis in adults

Answer 30

lytic in intestinal tissue causes lesions in intestines diarrhea

Answer 31

``` fecal oral (water) cruise ships ```

Answer 32

personal hygiene water treatment self-resolving

Answer 33

``` RNA non-enveloped 100+ types in upper respiratory tract mild resistance to detergents/ bases susceptible to acid common cold ```

Answer 34

lytic in lungs

Answer 35

``` airborne droplets hands can survive in environment for a few days via fomites americans have 3 infections / year ```

Answer 36

wash hands no vaccine because too many types symptomatic treatment

Answer 37

``` inflammation of liver jaundice hemoglobin -> bilirubin, biliverdin recycling liver inflam -> deposit intermediates in liver -> jaundice fever lack of appetite nausea dark urine pale feces infection resolves in 2-4 weeks ```

Answer 38

``` RNA non-enveloped enterovirus acute denatured capsid proteins by boiling survives weeks in environment and stomach ```

Answer 39

infects enterocytes, also mouth and throat spreads through blood to liver lytic in liver cleared by infected cells, can cause further damage no chronic infection

Answer 40

``` fecal oral direct or indirect contact sometimes saliva 50% US pop exposed, 90% developing countries low mortality ```

Answer 41

``` formaldehyde killed vaccine travelers, children, anal-oral sex proper hygiene sewage disposal no antivirals lifetime immunity ```

Answer 42

DNA enveloped double stranded DNA in liver cells

Answer 43

``` RNA -> DNA with reverse transcriptase DNA -> viral proteins sometimes lysogeny with integration DNA -> viral DNA polymerase -> DNA lytic in liver cells ```

Answer 44

``` blood sex during birth direct transmission only asians more susceptible 90% infected neonate -> chronic carriers cirrhosis: liver tissue replaced by scar tissue; or liver failure or cancer ```

Answer 45

virus subunits vaccine health professionals, STDs, IV users, transfusions treatment only for chronic carriers alpha interferon inhibitors of reverse transcriptase and viral DNA polymerase

Answer 46

``` RNA enveloped single stranded RNA hypervariable genome in liver cells persistant chronic ```

Answer 47

RNA -> DNA reverse transcriptase lysogeny with integration hard to control replication because virus keeps changing immune system attacks alcoholism increases disease 75% infected become chronic carriers 10% of cases cause cancer, cirrhosis, liver failure

Answer 48

blood transfusion rare: sex or during birth 4 million americans infected direct contact only

Answer 49

avoid blood contact (drug users) alpha interferon reverse transcriptase inhibitors new drugs with 50%+ cure rate

Answer 50

``` RNA enveloped defective virus only infects HBV individuals no capsid protein genome persistant chronic ```

Answer 51

uses capsid of HBV | increases liver damage speed

Answer 52

same as HBV | direct contact

Answer 53

prevent HBV | no treatment

Answer 54

RNA non-enveloped acute major cause of enteric transmitted hepatitis in asia, africa, india, mexico, but rare in US (diff from HAV) can infect pigs

Answer 55

20% infected pregnant women -> fatal hepatitis (75% mortality)

Answer 56

fecal oral same as HAV direct and indirect contact

Answer 57

vaccine avoid contaminated water/food no treatment

Viruses Flashcards

(81 cards)