Zika Virus: What We Know and Don t Know Meg Fisher, MD Medical Director. Disclosures. Objectives

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1 Zika Virus: What We Know and Don t Know Meg Fisher, MD Medical Director Disclosures I have no financial disclosures. I do not plan to discuss off label uses of medications. Objectives Discuss the epidemiology of Zika virus Advise a parent or teen regarding travel to Zika areas Evaluate a newborn whose mother had Zika virus infection 1

2 Hot Topics in ID: Zika Virus Zika Virus Discovery: 1947, Zika Forest, Uganda First human disease: Nigeria 1953 Few cases recognized for next 50 years 2007 Micronesia: 5000 of 6700 infected French Polynesia: 32,000 cases Other islands then 2015 Brazil: > 1 mil Zika virus Flavivirus, African and Asian genotypes Mosquito transmitted: Aedes species Africa: monkeys and humans Suburban urban: humans Vectors: A. aegypti, A. albopictus 2

3 Areas With Risk of Zika wwwnc.cdc.gov/travel/files/zika areas of risk.pdf Zika Transmission, Florida update.html Zika Transmission, Texas update.html 3

4 Areas With Risk of Zika Tropical islands Central and South America, Sub Saharan Africa, India, SE Asia Interactive map on CDC website: update.html Zika Cases in the US 2015: not a reportable disease US: 61 travelers Territories: 1 travel, 8 local 2016 US: 4830 travelers Territories: 36, local 48 other 2017 (as of May 10, 2017) US: 110 travel Territories: case counts.html 4

5 Zika Transmission Aedes mosquito: aggressive, day time biters, bite at night also Sexual transmission Pregnant woman to her fetus Blood transfusion Laboratory accident Range of A. aegypti in US 2016 Zika Transmission 5

6 Aedes aegypti Adult life span 2 4 weeks, fly 400 meters Aedes aegypti Best transmitter Feeds primarily on humans, live close Day and night biting, in and outdoors Almost imperceptible bites Multiple bites during feeding Zika, dengue, chikungunya, yellow fever Sexual Transmission Virus in semen for weeks Virus in vaginal secretions Frequency of transmission unknown Duration of risk unknown 6

7 Mother to Fetus Zika virus RNA detected in placenta, amniotic fluid and fetal tissues Fetal loss, stillborn, brain abnormality Frequency and risk unknown Peripartum transmission reported Registry: providers/registry.html Other Routes Blood transfusion Laboratory accidents Healthcare workers Clinical Illness Only 1 in 5 have symptoms Fever, rash, joint pain, conjunctivitis Mild, self limited illness, lasts days Incubation: few days (range 3 12) Infection in a fetus: microcephaly Cases of Guillain Barré syndrome 7

8 Neurologic Complications Guillain Barré syndrome: Polynesia (38 cases) and Brazil Baseline GBS: 1 2/100,000 people Microcephaly increased incidence Baseline: 6/10,000 live births Fetal Infection Virus is neurotropic and destroys brain Microcephaly, fetal brain disruption, ocular abnormalities In utero ultrasounds: calcification Zika confirmed in fetal brain tissue* Highest risk in 1 st trimester *DOI: /NEJMoa Diagnosis Detection of viral RNA by RT PCR: viremia lasts about a week, urine longer Specific IgM by MAC ELISA: rises about a week after illness and lasts months Cross reacting antibodies: dengue + Plaque reduction neutralization test (PRNT) 8

9 Treatment Supportive care Note most will have no symptoms Monitor and test exposed pregnant women Register pregnant women providers/registry.html Prevention Travel Avoid travel to areas with active Zika transmission If you travel, avoid mosquito bites If you travel, avoid unprotected sex wwwnc.cdc.gov/travel/page/zika travel information Prevention Mosquitoes Clothing: cover up Screens and air conditioning; bed nets Repellents: DEET, picaridin, IR3535, oil of lemon eucalyptus, or para menthane diol follow directions! Permethrin treated clothing and gear 9

10 Prevention Sex Recommendation for pregnant women: abstain or use condoms consistently Recommendations for non pregnant: abstain or use condoms consistently Testing of men of uncertain value about pregnancy.html Duration for Males Male traveler no symptoms: at least 6 months after departure Male resident: consider while active transmission persists transmission prevention.html Duration for Females Pregnant woman: throughout pregnancy Non pregnant: at least 8 weeks after symptoms or exposure transmission prevention.html 10

11 Prevention Other Screen potential blood donors Laboratory workers: routine safety measures Healthcare people: avoid needle sticks Recommendations Pregnant women forego travel to areas with Zika virus transmission Exposed pregnant women should be tested If congenital infection is suspected, many tests are recommended Effects of Zika on Fetus Microcephaly: fetal brain disruption Imaging: calcification, abnormal gyri, decreased brain volume, + Hypertonia, hypotonia, spasticity, irritability, seizures Eyes: chorioretinal atropy, optic disc hypoplasia, pallor and cupping 11

12 Zika in Pregnancy Data as of April 25, 2017 United States: 1793 pregnant women Outcomes: 1409 completed pregnancies 58 newborn with birth defects 8 fetal losses with defects US Territories: 3700 pregnant women Outcomes information not available outcomes.html Pregnancy Outcomes Any evidence of possible recent Zika: 51/972 (5%); microceph. 43, other 8 Confirmed Zika infection: 24/250 (10%); microceph. 18, other 6 Zika infection in first trimester: 15/60 (15%); microceph. 8, other 1 Postnatal studies: imaging in only 25%, Zika virus testing in 65% Management of the Baby Laboratory testing recommended: Infants born to mother with evidence of Zika virus infection during pregnancy Infants with abnormal clinical or imaging findings and maternal epidemiologic link rrt PCR (serum, urine) and IgM for Zika 12

13 Baby of Zika + Mother Zika virus testing: rrt PCR, IgM within 2 days; if CSF obtained, test it as well Comprehensive physical examination Neurologic examination Postnatal head ultrasound Standard hearing screen Report to Registry Interpretation of Tests Positive infant serum or urine rrt PCR confirms congenital Zika virus infection +Zika IgM, rrt PCR indicates probable congenital Zika virus infection; PRNT Zika IgM, rrt PCR means not infected Report Positives to Public Health Confirmed Congenital Zika By 1 month: Comprehensive ophthalmologic exam and hearing by Auditory brainstem response (ABR) Follow up depends on whether abnormalities are present providers/infants children/zika evaluation.html 13

14 Baby With Abnormalities CBC, metabolic panel (liver function) Coordinated evaluation by multiple specialists within first month of life Assess vision, hearing, feeding, growth, neurodevelopment and endocrine function in first year providers/infants children/zika evaluation.html Baby With Abnormalities Consultation: Neurology (imaging), ID (r/o other), Ophthalmologist, Genetics, Endocrine (hypothalmus, pituitary) Others: orthopedics, rehab, pulmonary, lactation, nutritionist, GI, speech, OT Psychosocial support; coordinated care My opinion: palliative care essential providers/infants children/zika evaluation.html Baby With Abnormalities Multidisciplinary team and medical home Monthly visits X 6: growth, development, immunize, guidance, support Neurologic exam at ages 1 and 2 months Refer to developmental specialist and early intervention services providers/infants children/zika evaluation.html 14

15 Baby With Abnormalities Repeat eye exam at 3 months Repeat ABR testing at 4 6 months, refer if abnormal Repeat thyroid studies (TSH, T4) at 2 weeks and 3 months, refer if abnormal Provide family and supportive services Just launched Zika Care Connect ( providers/infants children/zika evaluation.html Baby Without Abnormalities Medical home: growth, developmental screen at each visit, anticipatory guide Standardized devel. screen at 9 mos Repeat hearing test, 4 6 mos Provide family and supportive services providers/infants children/zika evaluation.html Anticipatory Guidance Encourage breastfeeding Watch for poor suck, swallowing difficulty, reflux, aspiration Sleep problems, excess irritability Monitor family for depression Social stigma, financial stress 15

16 Zika Prevention Avoid exposure: travel precautions Avoid mosquitoes Sexual transmission: abstinence or condoms Stay tuned for more information Mosquito Control Public health: Integrated Vector Management Community cleanup campaigns (tire removal, trash pickup, removal and cleaning of small and large containers). Insecticide resistance testing Larvicides in containers and bodies of water that cannot be removed or dumped. health partners/vector control us.html The End 16