Viral Infections Flashcards
General notes on viruses
Dx tests/Tx
not always required
General notes on viruses
Prognosis
usually benign and self-limited
General notes on viruses
need for consultations
unlikely with typical presentations
Herpes Simplex Virus
where does the virus lie dormant?
in neurons
can have asx viral shedding
Herpes Simplex Virus
when does the virus reactivate
- follows minor infection, trauma, stress, sun exposure, menstruation
Herpes Simplex Virus
Consideration in pregnancy
risk of transmission during delivery
Herpes Simplex Virus
what to do during genital flare up during birth?
deliver via c-section to not spread to baby
Herpes Simplex Virus
HSV 1 epi
- common for oral and genital ulcers in young females
- positive serology common
Herpes Simplex Virus
HSV 2 epi
- most common cause of genital ulcers in developed world
- many unaware they are infected
Herpes Simplex Virus
describe lesions
4 things
- skin or mucous membrane
- vesicle changing to painful ulcer over several days
- prodrome of pain
- regional tender lymphadenopathy
Herpes Simplex Virus
what does suppressive tx do?
reduces transmission and sx
Herpes Simplex Virus
ophthalmicus heals well when limited to?
epithelium
Herpes Simplex Virus
ophthalmicus when involves the stroma can lead to?
3
- uveitis
- scarring
- blindness
Herpes Simplex Virus
Complications
- meningitis
- disseminated infection
- bell palsy
- esophagitis/proctitis
- erythema multiforme minor
- stevens-johnson syndrome
Herpes Simplex Virus
Dx for meningitis
- CSF for HSV DNA PCR
- CSF for HSV antibodies later in disease
Herpes Simplex Virus
Dx for oxular disease
- branching ulcers that stain with fluorescent
Herpes Simplex Virus
Dx GI disease
- biopsy with HSV PCR and culture
Herpes Simplex Virus
Dx pneumonia
- diagnosed by clinical, pathologic, and radiographic findings
Herpes Simplex Virus
Tx
- treat to inhibit replication for both hsv-1 and hsv-2
- Aycylovir- dosage varies based on goal of tx
- Trifluridine- for eye infection
Herpes Simplex Virus
Acyclovir- 3 categories for tx
- mild-moderate disease
- severe disease/immunocompromised
- suppression
Herpes Simplex Virus
Acyclovir- mild/moderate tx
dosage/duration/freq
400-800mg PO, Q8 hrs, 10 days
Herpes Simplex Virus
Acyclovir- severe disease/immunocomp
dosage, duration, freq
5-10mg/kg IV, Q8 hrs
Herpes Simplex Virus
Acyclovir- suppression
dosage, frequency, duration
400-800mg PO, Q12 hrs
Varicella
AKA
chicken pox
Varicella
incubation period
10-20 days
Varicella
mode of transmission
respiratory droplets
contact with lesions
Varicella
most typically presents in:
children
Varicella
varicella zoster virus aka
human herpesvirus-3
and this = varicella/chicken pox
Varicella
herpes zoster aka
shingles
Varicella
sx & signs
- fever
- malaise
- headache
- abd pain
- rash
Varicella
describe rash
- contagious from 1-2 days before rash until all lesions crusted
- successive crops, lesions in dif stages development
crust 4-7 days after onet - maculopapular rash that quickly transforms to vesicles that become pustular and then crusts
Varicella
distribution of rash
- starts on face/scalp/trunk
- spreads to extremities later
Varicella
change in incidence due to vax
79% decrease
Varicella
dx
clinical
Varicella
treatment
- usually self-limiting in children, treat symptomatic
- Acyclovir 20mg/kg PO, Q24 hrs, 7 days
- initiate treatment w/in 24 hrs of dx
Varicella
max dose of acyclovir daily
800 mg
Varicella
pt’s at highest risk of complications
4 groups
unvax children/adults
pregnant women
immunocomp
Varicella
complications
4 things
- skin infection
- pneumonia
- encephalitis
- death
Varicella
what do we give for PEP?
immune globin varizig IM
Varicella
who do we give PEP to?
those at higher risk of complications
Congenital Varicella
what can happen if preg women becomes ill?
6 things
- spontaneous abortion
- chorioretinitis
- catarats
- limb atrophy
- cerebral cortical atrophy
- neurological disability
Congenital Varicella
Rate of spontaneous abortion if infection is during first trimester?
3-8%
Congenital Varicella
varizig rec to who?
4 groups
- newborns with significant exposure to VZV
- neonates whose mom’s have s/s within 5 days before or 2 days after delivery
- hosp preterm infants born > 28 wks whose mom’s aren’t immune (no vax hx, or neg serology)
- hosp permature infants born < 28 wks or wt < 1000g
Herpes Zoster
describe rash
- tingling
- pain
- eruption of vesicles in a dermatomal distribution
- evolving to pustules followed by crusting
Herpes Zoster
how do people become ill with this?
VZV remains latent in root ganglia after varicella infection.
Herpes Zoster
Primary infection= ?
Secondary infection= ?
- chicken pox
- shingles
Herpes Zoster
vax series?
2 dose vax rec at age 50
Infectious Mononucleosis
most common virus
epstein barr virus (EBV)
Infectious Mononucleosis
EBV AKA
human herpesvirus-4 (HHV4)
Infectious Mononucleosis
who is most affected?
age/gender/race
young adults (15-25)
gender/races equally
Infectious Mononucleosis
how long is saliva infectious?
up to 6 mo after sx onset
Infectious Mononucleosis
incubation period
30-50 days
Infectious Mononucleosis
what can insufficient cellular immune responses result in?
EBV induced malignancy
Infectious Mononucleosis
signs & sx
5 categories, 10ish things
- abrupt onset severe sore throat/pharyngitis with posterior cervical lymphadenopathy
- gradual onset low-grade fever, malaise, arthralgia, myalgia
- splenomegaly
- abd pain/discomfort
- hepatomegaly (meh, elevated ALT/AST)
Infectious Mononucleosis
how many pts have mono rash?
15%
Infectious Mononucleosis
describe mono rash
- faint and not pruritic
- first on trunk and upper arms
- extends to face and forearms
Infectious Mononucleosis
what makes the mono rash more intensive or extensive?
abx use!
seen 2-10 days after cessation of tx
Infectious Mononucleosis
complications
6 things
- severe upper airway obstruction
- splenic rupture
- fulminant hepatitis
- encephalitis
- severe thrombocytopenia
- hemolytic anemia
Infectious Mononucleosis
Dx
- Lymphocytosis
- Heterophile antibodies
Infectious Mononucleosis
what do we see in mono with heterophile antibodies?
- pos 2-9 wks after infection
- can be pos for > 1 yr
- not everyone develops these after infection
Infectious Mononucleosis
what test for heterophile antibodies?
heterophile agglutination test (monospot)
Infectious Mononucleosis
Tx
- supportive care
- hydration
- antipyretics
- analgesics
- avoid contact sports for at least 4 wks to reduce risk of splenic rupture
Cytomegalovirus (CMV)
sx in general population?
similar to what in immunocompromised pts?
- asx in general pop
- mono like in immunocomp group
Cytomegalovirus (CMV)
mode of transmission
5 components
- close contact
- sexual
- blood transfusion/transplant
- occupational
- perinatal
Cytomegalovirus (CMV)
Complications
4
- retinitis
- GI/hepatobiliary
- pneumonitis
- neurologic syndromes
Congenital CMV
Neurodevelopmental Complications
5 things
- sensorineural hearing loss
- cerebral palsy
- intellectual disability
- vision impairment
- seizures
Congenital CMV
Dx and Tx
- Dx: test urine or saliva
- Tx: ganciclovir or valganciclovir
Cytomegalovirus (CMV)
Dx
PCR test
Cytomegalovirus (CMV)
Tx
general pop vs immunocompro
- general: supportive care only
- immunocomp: ganciclovir IV or valganciclovir PO
Rotavirus
most common in children of what ages?
6 mo to 2 yrs
Rotavirus
3 factors that play a role in pathogenesis of diarrhea
- loss of brush border enzymes
- direct effect of rotavirus enterotoxin NSP4
- activation of enteric nervous system
Rotavirus
Sx
3 big ones
- vomiting
- watery, nonbloody diarrhea
- fever
Rotavirus
Sx/Complications of severe cases
- dehydration
- seizures
- death
Influenza
Seasonality?
fall/winter
Influenza
Types
3
- Influenza A
- Influenza B
- Influenza C
Influenza
which are most common?
which rarely results in illness?
- A & B
- C
Influenza
Who is at highest risk?
6 categories
- children
- elders
- immunocompromised
- pregnant
- co-morbid conditions
- morbid obesity
Influenza
Incubation period
1-4 days
Influenza
Influenza
Clinical presentation
- fever/chills/sweats
- myalgia
- headache
- malaise/fatigue
- anorexia
Influenza
Dx
- rapid molecular assays (NP swab)
- PCR testing (rec for hosp patients)
- viral culture (only in unusual cases)
Influenza
Tx
- Supportive care (rest/fluids/antipyretics/analgesics/anti-tussives)
- Oseltamivir
- Zanamivir
Influenza
dosage/duration/freq of oseltamivir
adults only
75mg PO, Q12 hrs, 5 days
Influenza
admin route of zanamivir
inhaled or IV
only used if resistance to oseltamivir
Influenza
admin route of paramivir
IV- use if they cannot tolerate Tamiflu
Influenza
Who to treat?
adults/children who meet the following criteria:
* hospitalization
* severe or progressive illness
* high risk patients
* children < 2 yrs or > 65 yrs
* pregnant women and those within 2 wks of being postpartum
Influenza
consider treating
- outpatients with illness onset < 48 hrs before presentation
- patients who have high risk contacts at home
- sx health care providers
Influenza
Decision to Admit
admit if severe illness/progressing illness in pregnant women, children < 5 y/o, adults > 65 y/o
Influenza
Decision to admit to ICU
- rapidly declining respiratory function/hypoxia
- bilateral diffuse pneumonia
- hemodynamic instability
Influenza
Risks of influenza illness during pregnancy?
- increased risk for hospitalization but not mortality
- increased risk for pre-term birth or SGA infants
Influenza
when to vax pregnant women
any trimester
SARS-COV-2 (COVID)
incubation period
< 14 days
SARS-COV-2 (COVID)
typical sx
general
URI
fever
cough
SARS-COV-2 (COVID)
Complications
- respiratory failure
- cardiovascular
- thromboembolic complications
- neurologic complications
- inflammatory complications