viral infections of the bone, muscle joints II Flashcards Preview

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Flashcards in viral infections of the bone, muscle joints II Deck (29):
1

smallpox symptoms

- abrupt onset of high fever >101 F
- malaise, headache, muscle pain, nausea
-lesions- starts in mouth and then goes thru to skin- face and extremities (centrifugal distribution)
- COMMON TO HAVE PALMS OF HANDS AND SOLES OF FEET INFECTED(DIFFERENT FROM CHICKENPOX)
-SYNCHRONOUS EVOLUTION OF LESIONS -UNLIKE CHICKEN POX THAT VARY

2

Evolution of small pox

starts as macule and then turns into a pustule and then scabs over

3

what causes smallpox

-variola virus
- poxiviridae
- large dsDNA
- REPLICATES IN THE CYTOPLASM (like moluscum contageosum)
-USES A LOT OF ITS OWN ENZYMES FOR REPLICATION
- STRICLY HUMAN VIRUS

4

transmission of smallpox

- fomites, contact with lesions, rarely spread aerosol
- individuals are virulent until scabs fall off

5

what does variola/smallpox cause

-bacterial infection of the skin
- arthritis
-encephalitis
- respiratory tract infection
- fatality of 30%
-hemorrhagic and flat forms of smallpox

6

small pox vaccine

-NOT LIVE-ATTENTUATED
-IT IS THE LIVE STRAIN OF VACCINIA VIRUS (another member of the poxiviridae family) THAT ALLOW CROSS PROTECTION FOR SMALLPOX
-Vaccine stopped in 1972

7

how are smallpox and chicken pox distinguished?

- smallpox has centrifugal infection - infection on outter extremities- lesions on hands and feet, lesions all in same phase
-chicken- has centripetal infection- infection of core- no lesions on hands and feet, has crops of lesions meaning many lesions in different phases

8

what sort of prophylaxis is available for postexposure to small pox

- vaccine within 3 days- prevent or significantly lessen disease outcome
- vaccination at 4-7 days- partial exposure or lessening disease

9

progress of disease of measles

- prodrome for 2-4 that include fever and 3 C's:
cough, coryza (runny nose), conjunctivitis ****
-also have KOPLIKS SPOTS IN MOUTH = MEASLES
-rash for 5-6 days that starts at the scalp and spreads down
-anorexia, diarrhea, lymphadenopathy

10

what is measles virus?

- ssRNA
- enveloped
- F gene important for FUSION
- HA PROTEIN IMPORTANT FOR ATTACHMENT
-one antigenic type

11

measles transmission

-respiratory- can last up to 2 hrs in the air
- shed in nasopharynx from prodrome to 4 days out
-HIGHLY CONTAGIOUS
-Incubation is 10-12 days

12

diagnosis of measles

- koplicks spots- rash in mouth lasting more than 3 days- white spots with red boarder
- confirm with lab

13

when an adult gets measles, what is it usually a result of? a kid?

adult- due to measles virus
kid- usually due to bacterial superinfection

14

complications of measles

- diarrhea, otitis media, pneumonia, encephalitis, seizures and death

15

how are measles prevented?

- IG within 6 days following exposure

16

what qualifies for resistance for measles

- document receipt of 2 doses of live measles vaccine
- lab evidence of immunity
-documentation from a doc verifying you had it
-born before 1957-assumed anyone got it that time

17

measles vaccine
vaccine schedule

-live attenuated
-prepared in chick embryo fibroblasts
- combined with Mumps and rubella
-schedule: kids- at 12-15 months and adults whenever traveling or post HS or health care worker
those born after 1957- one dose

18

german measles

- maculopapular rash that looks like measles but FAINTER
-DOES NOT COALESCE
-prodrome- fever, lymphadenopathy, URT symptoms
-sometimes associated with arthralgia or ARTHRITIS

19

what are german measles caused by?

-caused by infection of rubella virus

20

Congenital rubella syndrome

- obtained when mom has rubella
-baby has DEAFNESS AND CATARACTS, CHF, retinopathy
-purpura- hepatomegaly, jaundice, microcephaly, meningoencephalitis, radiolucent bone disease

21

rubella virus

- togaviridae fam
enveloped
- RNA genome

22

how is rubella transmitted

- respiratory route and primary replication in nasopharynx and regional lymph nodes
-viremia 5-7 days post infection
-time for infection to rash is 2 weeks

23

rubella vaccine

-live attenuated
- grown in tissue culture cells

24

fifth disease/erythema infectiosusm

-slap cheeks
- fever
-characteristic rash that begins at cheeks and goes to hands
-caused by B19 parvovirus

25

what is B19 parvovirus

-causes fifth disease
- ssDNA
-grows only in mitotic cells
utilizes host enzymes for genome transcription and replication

26

at does B19- fifth disease cause in terms of symptoms

- fever, rash in LACELIKE PATTERN
- usually self resolves in 2 wks
-50% of people are serotype pos
-GROWS IN HEMATOPOETIC CELLS IN BONE MARROW

27

When can B-19 virus be a problem?

-with patients who are always anemic- sickle cell people- can cause aplastic ctisis
- it can cause arthritis
- pregnancy complications and increase of CHF and hydrops fetalis (swelling of fetus)

28

roseola infantum

-caused by herpes virus 6- dsDNA present in almost everyone
herpes virus 6- replicates in T and B cells
-high fever that last 4 days FOLLOWED by rash that last 24-48 hrs
-*characteristic timing
-

29

herpes virus 7

-replicates in CD4 T cells
- present in saliva of approx. 75% of adults
infection occurs after HSV6