Perinatal infections Flashcards
What is the leading cause of neonatal chorioretinitis?
a. CMV
b. Rubella
c. Syphilis
What percentage of pregnant women are IgG+ for HSV-2?
20-30%
What percentage of women HSV seroconvert during pregnancy?
2-4%
What percentage of HSV-2 infected people are not aware of having the infection?
75-90%
Symptoms of newly acquired HSV infection
Asymptomatic in 70% of pregnant women
30% - range from minimal lesions to widespread genital lesions, tender regional lymph node enlargement, fever, malaise, headache
HSV-1 causes what percentage of oral infections? genital?
90% oral
10% genital
HSV-2 causes what percentage of oral infections? genital?
10% oral
90% genital
(but among college-age populations, majority of new cases of genital HSV are HSV-1)
What percentage of neonatal HSV results from women who acquire HSV-1 or -2 near term?
50-80%
What is a “nonprimary first-episode HSV infection”?
HSV-2 confirmed in a person with prior HSV-1, or vice-versa. Symptoms are usually milder than a first-episode primary infection.
What is reactivation (recurrent) genital herpes?
- Caused by reactivation of latent HSV, usually HSV-2.
- Over 90% of HSV episodes in pregnancy are recurrent or non primary 1st
- Symptoms last 7-10 days, with low viral load shedding for 3-5 days.
What is the incidence of neonatal HSV after a vaginal delivery during a first episode primary infection?
25-50%
What is the incidence of neonatal HSV after a vaginal delivery during a recurrent infection?
<1%
Why is the incidence of neonatal HSV after a primary maternal infection higher?
The infant of the mother with primary HSV lacks the protection of transplacental type-specific antibodies. The major sites of intrapartum viral entry are the neonatal eys, nasopharynx, or a break in the skin. Transplacental infection is rare.
What is GBS?
Streptococcus agalactiaeAn encapsulated gram-positive coccus that colonizes the vaginal & GI tract
Manifestations of GBS in the mother
Urinary tract infectionChorioamnionitisEndometritisBacteremiaStillbirth
What are the 2 types of newborn GBS infection?
Early-onset - usually within first 24 hrs of life, up to 6 days after birthLate-onset - Usually at 3-4 weeks of age, can occur any time from 7 days - 3 months
Symptoms of neonatal GBS
Early-onset:Respiratory distressShockPneumoniaMeningitis (occasionally)Late-onset:Bacteremia (common)Meningitis (common)Poor feedingIrritabilityExtreme drowsinessListlessnessLocalized infection: middle ear, sinuses, bones, joints, skin
Prevalence of asymptomatic GBS anovaginal colonization in pregnant women
20%, can be transient or persistentA substantial portion of women colonized in one pregnancy will not have colonization during a subsequent pregnancy
Percentage of neonates born to mothers colonized with GBS that are colonized themselves
40-75%
Risk factors for early-onset GBS disease
Prolonged ROM (>/= 18 hrs)Preterm birth (but >80% GBS are term)Termp >/= 38 deg CMaternal GBS colonization btw 35-37wPrevious infant with invasive GBS diseaseMaternal choioBlack or HispanicGBS bacteriuria during pregnancyDM or GBS colonization in a previous pregnancy are not risk factors
Neonatal mortality due to GBS disease
5%25% if < 33w GA
Is there a vaccine for GBS?
accination against GBS is potentially the most effective method of preventing the morbidity and mortality caused by infection. GBS vaccines have been investigated as a tool to reduce maternal colonization and prevent transmission to the neonate; however, a licensed vaccine is not yet available.
What percentage of neonates with early-onset GBS sepsis are born to women without risk factors?
20.00%
How effective is a screening-based strategy compared to a risk factor-based strategy for GBS?
> 50% more effective for early-onset GBS, but does not affect the incidence of late-onset GBS sepsis