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Viral Infections in Pregnancy. Deborah Money, M.D., FRCSC Associate Professor, Dept. of Ob/Gyn, U.B.C. Executive Director, Women’s Health Research Institute. Plan for talk:.
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Viral Infections in Pregnancy Deborah Money, M.D., FRCSC Associate Professor, Dept. of Ob/Gyn, U.B.C. Executive Director, Women’s Health Research Institute
Plan for talk: • To refresh information on viral infections that are (should be) routinely screened for in pregnancy – what to know if the result comes back positive!!! • Remind about viral infections that are screened for to prompt vaccination • Brief discussion on viral infections that are high risk in pregnancy and can be prevented • Mention the unusual viral infections that can cause congenital or neonatal infections
Viral infections to screen for in pregnancy • To manage in pregnancy: • Hepatitis B • HIV • Herpes simplex – by history • To determine need for vaccination: • Rubella • Varicella – by history and/or by serology
What to do if results are positive? – HepBsAg pos • If a new result • Need to do full work up for newly diagnosed hepatitis B including liver function, level of infectivity and need for maternal therapy? • INFANT PROPHYLAXIS • Hepatitis B immune globulin after birth • Hepatitis B vaccine series • Only 95% effective – or less in HepBeAg positive • Need to do follow up testing on infants to determine they are not infected – at 6 months • ? Role for maternal treatment to prevent infant infection
What to do if results are positive? HIV positive • DON’T PANIC - Call an expert and review current approach to HIV in pregnancy • Call patient in to review results in person • Do full review of adult health status and risks of transmission to others, safety assessment • Laboratory baseline: CBC, LFT’s, renal function, CD4 count, HIV viral load, other STI screening including Hep B and C, TB testing – other based on history • Prevention of transmission to others – partner testing/testing of older children etc. • Plan adult HIV management and mgmt of co-inf/co-morbidities
HIV positive in pregnancy • Need for antiretrovirals for maternal health? – start immediately, with prophylaxis for opportunistic infections if CD4 warrants • Prevention of MTCT: • Combination ART from 14-18 wks to delivery and beyond if adult disease warrants • Modified delivery – C/S if not virologically suppressed • No breast feeding • AZT in labour and to baby post partum x 6 wks • MESSAGE – 25% baseline risk of transmission of HIV without prevention - <1% with full prevention menu
Screen positive for recurrent genital herpes • Routine screening by history of lesions (not by serology) • If positive – risk of transmission at delivery is related to whether lesions/symptoms are present • If lesions/symptoms present at time of delivery or PROM • risk of transmission is 2-4% • recommend C/S • If not present – risk is 0.02-0.04% so recommend vaginal delivery
Screen positive for recurrent genital herpes • Recommend antiviral treatment in late pregnancy to decrease chance of recurrent lesions and shedding: • Acyclovir 400mg tid from 36 weeks to delivery • OR • Valaciclovir 500mg bid from 36 weeks to delivery • Either show a statistically significant reduction in lesions and shedding of HSV at time of delivery • Not proven to decrease neonatal HSV
Herpes simplex: neonatal transmission risks • IF new infection in pregnancy then need to consider remote chance of congenital herpes (from 1st or 2nd trimester transmisstion) • IF new infection in 3rd trimester then risk of neonatal herpes is 30-50% • SO recommend C/S and very careful follow-up of the infant
Rubella and Varicella screening • VACCINE PREVENTABLE • Both still cause congenital disease due to non-immune women becoming infected in pregnancy • Live attenuated vaccines – can be delivered post partum prior to discharge in non-immune women • Rubella antibody testing to determine immunity • Varicella – if history of disease do not need to test but if negative history then test for VZV IgG to check for immunity
Congenital Rubella Syndrome • <12 weeks 50-90% risk- spontaneous abortion or severe abnormalities • IUGR, cardiac (PDA or pulm artery stenosis), hearing defects, visual impairment(catarracts), encephalitis, blueberry muffin syndrome (purpura) • >12 weeks – 20 weeks – 30-50% - less severe • hearing, language, autism, endocrine, visual, dental
Preventable/treatable viral infections that cause congenital/neonatal disease • Varicella • CMV – maybe treatable • Parvovirus B19
Varicella zoster (chicken pox) – 2 scenarios • Pregnant woman exposed to chicken pox • Determine immune status • If non-immune give VZIG within 72 hrs to decrease chance of maternal varicella infection • Watch for up to 21 days for signs of disease
Pregnant woman develops chicken pox • Use infection control precautions • Treat with acyclovir/valaciclovir for maternal health if evidence of severe disease or respiratory compromize • May need to admit • IF > 20 weeks – very unlikely to cause congenital disease • IF < 13-20 weeks – 2% risk of congenital varicella • If < 13 weeks – 0.4% risk of congenital varicella • If 2 days before or 5 days after birth – give VZIG to infant
Congenital varicella • rare complication • Manifestations primarily due to recurrent in utero zoster: • neuropathic, cutaneous, ocular, musculoskeletal, IUGR, neonatal zoster, limb hypoplasia • Can detect by U/S • Follow monthly throughout pregnancy
CMV in pregnancy • Most common cause of hearing loss in children • Very rarely diagnosed in pregnancy • Main worry is primary in pregnancy • DO NOT recommend screening • Test only if symptomatic mother or abnormal ultrasound • Serology not a good screen • Need to do viral testing of mother if suspected • Experimental treatment with CMV IVIG can be considered
Parvovirus B19 (Fifth’s disease) • Common in schools and daycares • Routine screening not standard of care • Manifestations in children- erythema infectiosum – low grade fever and slapped cheek facial rash • Adults – usually asymptomatic but can cause arthralgias, fever, adenopathy, and mild arthritis – rash is very rare • 50-75% of adults are immune • Pregnancy – causes fetal anemia due to destruction of red blood cell precursors – can be treated and recover
Parvovirus in pregnancy • Pregnant woman exposed to parvovirus – often in school or daycare setting • Test for Parvovirus IgG – if positive, is immune and can reassure • If negative – watch for evidence of disease – recheck for seroconversion • Pregnant woman develops parvovirus or seroconverts • Refer to level 3 centre to follow weekly x 8-12 wks with serial ultrasound that includes MCA doppler to determine if fetal anemia/hydrops is developing • If abnormal – may need fetal blood transfusion
Other infections of importance • Hepatitis C • Screening not current standard of care • Up to 2% of pregnant women are positive – less than ½ are aware of their infection • 5-10% rate of infant transmission – asymptomatic at birth • Need to manage maternal health and conduct modified delivery to decrease risk of transmission • Breast feeding seems to be safe
Infections that primarily affect the mother antenatally or post partum: Influenza • Seasonal Influenza and novel pandemic H1N1 • Is not transmitted to the fetus in utero • Can cause very serious illness in the mother • Complications for the fetus/infant related to level of illness in the mother and poor placenta perfusion/oxygenation • Vaccine preventable and partly treatable
Descriptive characteristics of H1N1 in Canada to Aug. 22, 2009 *Of women aged 15-44 years
Approach for 2010-2011 season • Recommend influenza vaccine to ALL pregnant woman with emphasis on woman who will be in 2nd/3rd trimester during peak of flu season • Safe in pregnancy – inactivated protein based vaccine – cannot get influenza from the vaccine, no adjuvant, does contain trace egg protein, 2 products contain thimerisol, 2 are thimerisol free • 2010-2011 TIV vaccine contains: • A/California/7/2009 (H1N1-like), A/Perth/16/2009 (H3N2)-like, B/Brisbane/60/2008 (Victoria lineage)-like antigens
Summary of most important viral infections in pregnancy • Potential congenital infections: • Rubella • CMV • Varicella • Parvovirus • Potential neonatal infections: • Herpes • HIV • Hepatitis B • Hepatitis C • Serious Maternal disease and fetal/neonatal morbidity: • Influenza
Suggested resources • www.sogc.org/guidelines - clinical guidelines for HSV, HIV, HCV, vaccines in pregnancy, parvovirus • www.phac-aspc.gc.ca • STI guidelines • Influenza statement