childhood viral diseases

Question 1

measles traits

Answer 1

paramyxovirus
-ssRNA genome
enveloped virion
polymerase is packaged into particle
replicate w/in cell 
humans= only host
fusion prot creates syncytia

Question 2

measles disease progression

Answer 2

inhaled
primary viremia - infection of respiratory ep. tiss (incubation period)
2’ viremia - symptom onset in LN, tonsils, lungs, GI tract and spleen
recovery -20 days after infection

Question 3

measles sympt. /diagnosis

Answer 3

characteristic rash “koplik spots”
fever, cough, coryza, and conjunctivis
id’ed by culture isolation, serology, ELISA

Question 4

side effects from measles (!)

Answer 4

immune suppression
opportunistic infections
blindness in vita A deficient children
acute disseminated encyphalomyelitis (neurological)
subacute sclerosing panencephalitis (neurological)

Question 5

measles prevention

Answer 5

vaccination-live attenuated (life long immunity)
providing vita A to reduce severity (#1 deadly childhood disease)
it’s extremely contagious! 15-20 non-vaccinated people per person

Question 6

respiratory syncytial virus biology

Answer 6

paramyxovirus
-ssRNA
enveloped (leaves cell thru budding)
replication w/in cell
infects ciliated respiatory ep. cells b/c they're colder than rest of body
fusion prot. creates syncytia
only in humans

Question 7

respiratory syncytial virus disease traits

Answer 7

inhaled and thru fomites (inannimate obj)
incubation 5 days then upper respiratory then lower respiratory sympt.
recovery after 7-12 days
no life long immunity b/c infects infants w/o good immune syst and only resp syst

Question 8

risk factors of respiratory syncytial virus disease

Answer 8

day care
school aged siblings
premature birth, male 
2nd hand smoke
lack of breast feeding

Question 9

treatment of respiratory syncytial virus

Answer 9

no vaccine or antivirals

only passive immunoprophylaxis used to prevent

Question 10

varicella zoster virus biology

Answer 10

alphaherpesvirus
dsDNA
large - hundreds of proteins
enveloped 
replicates w/in active cell

Question 11

chickenpox disease

Answer 11

inhaled
incubation period 10-21 days
symptoms fever, malaise, headaache,, rash
recovery = 2 weeks after symptoms but can stay latent an reactivate as shingles

Question 12

chickenpox prevention

Answer 12

vaccine- life long

antiviral - acyclovir (interfers w/ genome replication)

Question 13

poliovirus biology

Answer 13

picornavirus 
\+ssRNA
non enveloped
replication in cell 
leaves thru pore in cell membrane
humans only

Question 14

polio disease traits

Answer 14

ingested
minor viremia = infection of peyer’s patches in duodenum
major viremia = 2’ replication
fecal shedding of virus for 6 weeks

Question 15

polio in CNS

Answer 15

CNS involvement in 1:200
risk factors: physical exertion, trauma and tonsillectomy
replicates in gray matter
causes limb paralysis and sometimes respiratory paralysis

Question 16

polio prevention

Answer 16

vaccine (salk = killed or sabin = live attenuated)

Question 17

rotavirus biology

Answer 17

reoviridae
dsRNA - 11 segments
non-enveloped
replicate in cell
exit thru membrane disruption
membrane never exposed

Question 18

rodavirus disese

Answer 18

ingested
incubation 2 days
sympt vomiting and fever then diarrhea
virus sheds for weeks

Question 19

diagnosis and prevention and treatment of rotavirus

Answer 19

diag: antigens in stool
prevention: vaccines (multiple needed)
no antivirals
handwashing helps
treatment thru oral rehydration