Zika Virus Maternal & Fetal Effects John P. Elliott, MD Medical Director, Valley Perinatal Services Phoenix, Arizona
Objective of Presentation Sneeka Peeka at Zika
Disclosure I have nothing to disclose except I dislike mosquitoes.
History of Zika 1947 First identified in rhesus monkey in the Zika Forest, Uganda 1952 Isolated from humans 2007 YAP Islands, Micronesia 2013 French Polynesia 2015 - Brazil
Zika Virus Relatives Dengue Fever Yellow Fever Chikungunya West Nile Virus
Estimated range of Aedes Albopictus & Aegupti in USA, 2016 See: https://www.cdc.gov/zika/vector/range.html
Zika Virus Transmission Mosquito bite Sexual transmission Blood transfusion Maternal fetal transmission Lab exposure Transplantation
Prevention of Zika Infection Avoid travel to affected areas* Protect against mosquito bites Clothing DEET mosquito repellant products skin Premethrin products for clothing and netting Abstinence or condoms Males can transmit the virus in semen for up to 6 months after infection * see: https://wwwnc.cdc.gov/travel/page/zika-information
Tests for Zika Real-time reverse transcription-polymerase chain reaction (rrt-pcr) Zika IgM Test Plaque Reduction Neutralization Test (PRNT)
Maternal Infection Symptoms (3-12 days after exposure, last for 2-7 days) Mild fever Maculopapular pruritic rash Non-purulent conjunctivitis* Headache Arthralgias Myalgias *Patient in an area of possible Zika transmission
Fetal Infection All trimesters Risk of severe fetal CNS pathology: 1-13%. CNS abnormalities Hydrops Fetal growth restriction SAB Stillbirth
Ultrasound findings 18 weeks Microcephaly Def: HC 3 SD below the mean Intracranial calcification Often 3 rd trimester Irregularly shaped ventricular margin Increased periventricular echogenicity Cystic lesions Intraventricular adhesions Small cerebellum Enlarged Cisterna magna Increased CSF around the brain
Changes to my practice No documented local mosquito born infection. Every prenatal visit ask about: 1. Travel to areas with known Zika 2. Unprotected sex with some one who travelled to Zika area or who has been diagnosed with Zika
Providers in Area of documented local Zika Transmission Ask patients at each visit about possible exposure First Visit: Zika IgM If IgM+ or equivocal order reflex rrt PCR A + result is diagnostic of infection A result order PRNT If IgM is negative repeat at 16 and 24 weeks Screening US at 18 and 22 weeks
Symptomatic Patients < 2 weeks from onset of symptoms: Serum and urine rrt PCR for Zika RNA Positive infection confirmed Negative order IgM antibody Test for Zika and Dengue Positive or equivocal order : Plaque reduction neutralization test (PRNT) Negative (< 10 Zika PRNT) No Zika Positive ( 10) PRNT for Zika and Neg (< 10) PRNT for Dengue is confirmatory for Zika
If exposure was > 12 weeks prior Zika IgM and Dengue IgM Serial Fetal Ultrasounds
Confirmed Zika Infection Should prompt serial sonography CDC recommends every 3-4 weeks Start 6 weeks after presumed infection
Zika Virus Positive Women No evidence of risk in future pregnancies Want > 8 weeks after onset of symptoms before attempting pregnancy Zika Virus Positive Men Symptomatic infection wait 6 weeks before conception Asymptomatic infection wait 8 weeks before conception
Breast Feeding ZV has been isolated in breast milk No evidence of transmission to the baby
Summary of Zika Virus Management Inquire about possible exposure Maternal travel to endemic areas Maternal exposure to male with possible exposure If positive history of possible exposure ZV RNA by rrt PCR ZV IgM + Neutralizing Antibody Dengue Virus IgM + Neutralizing Antibody Ultrasound Assessment MFM If Positive Amniocentesis ZV RT PCR if + Dx of Exposure US q 3 4 Weeks Referral to MFM or ID for co-management Microcephaly offer termination
Updated interim guidance: testing and interpretation recommendations for a pregnant woman with possible exposure to Zika Virus - USA * see: https://www.cdc.gov/mmwr/volumes/65/wr/mm6529e1.htm
Exposure or Symptoms 2 12 weeks Asymptomatic living in an active Zika area or living in an active area & are in 1 st or 2 nd trimester IgM Serum Testing for Zika & Dengue Positive Zika or equivocal Presumptive Zika infection or Flavivirus infection Reflex Zika rrt PCR (Serum & Urine) Neg. for both No Zika Infection Positive Dengue or equivocal Presumed Dengue PRNT Serum Poss. Zika Infection Serum Neg. PRNT
Questionable Exposure to Zika or Symptoms < 2 weeks Serum & Urine rrt- PCR for Zika Test NEG Test POS = recent infection Neg. result No Zika Symptomatic IgM Testing for Zika & Dengue POS or equivocal Asymptomatic IgM Testing for Zika only (2-12 weeks from exposure) Recent infection with Zika or Dengue Plaque reduction neutralization testing (PRNT)
Resources CDC Zika Hotline 1-770-488-7100 Local Health Department CDC Division of Vector Borne Diseases: 1-970-221-6400 ACOG Zink webpage: www.acog.org/zika CDC Zink virus webpage: www.cdc.gov/zika
Thank You