Zika Virus Update for Emergency Care Providers

Transcription

1 Zika Virus Update for Emergency Care Providers What is this Zika Virus? Jeff Doerr Epidemiologist Southeastern Idaho Public Health Zika Virus Single stranded RNA virus Genus Flavivirus, Family Flaviviridae Closely related to dengue, yellow fever, Japanese encephalitis and West Nile viruses Transmitted to humans primarily by Aedes (Stegomyia) species mosquitoes Bridging mosquito species in yellow fever Bridging Zika is transmitted in a person to mosquito to person transmission cycle Aedes species mosquitoes Ae aegypti (Yellow fever mosquito) more efficient vectors for humans Ae albopictus (Asian Tiger mosquito) known more for Dengue Also transmit dengue and chikungunya viruses Lay eggs in domestic water-holding containers Live in and around households Aggressive daytime biters 1

2 Zika Virus Epidemiology First isolated from a monkey in Uganda in 1947 Prior to 2007, only sporadic human disease cases reported from Africa and southeast Asia In 2007, first outbreak reported on Yap Island, Federated States of Micronesia In , > 28,000 suspected cases reported from French Polynesia* * Who is at risk? Travelers to parts of Central and South America Oceania/Pacific Islands Check the CDC for the most up to date information In the United States: Puerto Rico Localized area in Florida and Texas Partners of patients with Zika Zika Virus in the Americas In May 2015, the first locally-acquired cases in the Americas were reported in Brazil Zika Disease in the United States and Territories in 2016 Currently, outbreaks are occurring in many countries or territories in the Americas, including the commonwealth of Puerto Rico and the U.S. Virgin Islands Spread to other countries has occurred Zika Virus in the Continental United States Local transmission of Zika virus has been reported in the continental United States, Florida and Texas Since 2011, there have been laboratory-confirmed Zika cases identified in travelers returning from areas with local transmission With current outbreaks in the Americas, cases among U.S. travelers will most likely increase 2

3 Zika Disease in the United States and Territories in 2017 What is an imported case? What is a locally acquired case? Approximate distribution of Aedes aegypti and Aedes albopictus in the United States* These maps DO NOT show Exact locations or numbers of mosquitoes living in an area Risk or likelihood that these mosquitoes will spread viruses These maps show CDC s best estimate of the potential range of Aedes aegypti and Aedes albopictus in the United States Areas where mosquitoes are or have been previously found Map courtesy of CDC *Maps have been updated from a variety of sources. These maps represent CDC's best estimate of the potential range of Aedes aegypti and Aedes albopictus in the United States. Maps are not meant to represent risk for spread of disease. Note about Zika and Mosquitoes Modes of Transmission Zika risk is determined according to altitude (height above sea level). Mosquitoes that spread Zika usually do not live at high altitudes (above 6,500 feet or 2,000 meters). The risk of getting Zika from a mosquito at high altitudes is less than at low altitudes. Aedes species mosquitoes, the mosquitoes that carry Zika, live in areas with certain ecological conditions (temperature, rainfall patterns, local plant growth, and human population density). CDC used elevation data to predict areas where the Aedes mosquitoes are unlikely to live. Our findings show that Aedes mosquitoes are not usually found above 6,500 feet (2,000 meters). 3

4 Zika Fever Symptoms Primary symptoms of illness are fever (<101.3 o F. or 38.5 o C.), rash, headache, conjunctivitis, joint pain and muscle ache Though the illness is similar to dengue fever, the symptoms are much more mild Symptoms usually last between 4 7 days Incidence and Attack Rates Infection rate: 76% (95% CI 68-77) Symptomatic attack rate among infected: 18% (95% CI 10-27) All age groups affected Adults more likely to present for medical care Usually no severe disease, hospitalizations, or deaths Conjunctivitis Note: Rates based on serosurvey on Yap Island, 2007 (population 7,391) Duffy M. N Engl J Med 2009 Distinguishing Zika from Dengue and Chikungunya Dengue and chikungunya viruses transmitted by same mosquitoes with similar ecology Dengue and chikungunya can circulate in the same area and rarely cause coinfections Diseases have similar clinical features Important to rule out dengue, as proper clinical management can improve outcome* Diagnosis Diagnosis is based upon travel history and symptoms Testing for Zika Our health department/state lab is not testing for Zika There are currently a variety of labs/testing procedures available commercially. *WHO dengue clinical management guidelines: 4

5 Laboratories for Diagnostic Testing Laboratory testing for Zika virus employs two different approaches: Molecular testing (real-time polymerase chain reaction (RT-PCR)) for patients who are currently exhibiting symptoms Serologic testing (IgM enzyme-linked immunosorbent assay (ELISA) and/or plaque-reduction neutralization tests (PRNT)) for patients who are currently asymptomatic or who are in the late stages of the virus (more than four days after symptom onset). Public health laboratories can conduct testing for Zika virus using a combination of IgM ELISA, RT-PCR and PRNT. Check with your local health department about testing. States are starting to reduce the amount of Zika testing due to testing being commercially available. Numerous commercial labs are offering Zika testing using a combination of IgM, and RT-PCR. Complicated Testing algorithm When in doubt: Check CDC website for updated guidance Check with your facility infection control contact Check with your local health department Initial Assessment and Treatment No specific antiviral therapy Treatment is supportive Rest Fluids Analgesics Antipyretics Suspected Zika virus infections should be evaluated and managed for possible dengue or chikungunya virus infections Aspirin and other NSAIDs should be avoided until dengue can be ruled out to reduce the risk of hemorrhage. Zika Virus Disease Surveillance Consider in travelers with acute onset of fever, maculopapular rash, arthralgia, or conjunctivitis within 2 weeks after return Inform and evaluate women who traveled to areas with Zika virus transmission while they were pregnant Evaluated fetuses/infants of women infected during pregnancy for possibly congenital infection and microcephaly Be aware of possible local transmission in areas where Aedes species mosquitoes are active 5

6 Preventive Measures No vaccine or medication to prevent infection or disease Primary prevention measure is to reduce mosquito exposure Pregnant women should consider postponing travel to area with ongoing Zika virus outbreaks Protect infected people from mosquito exposure during first week of illness to prevent further transmission ct-yourself.html 6

7 If families would like to speak to someone about a possible Zika virus infection or diagnosis during pregnancy and risk to the baby, please contact MotherToBaby. MotherToBaby experts are available to answer questions in English or Spanish by phone or chat. The free and confidential service is available Monday-Friday 8am-5pm (local time). To reach MotherToBaby: Call Chat live or send an through the MotherToBaby website Website: Mothertobaby.org Sexual Transmission of the Zika Virus We know: Zika virus can be sexually transmitted by a man to his sex partner(s), and this is of particular concern during pregnancy. Reported cases of sexual transmission involved sex without a condom with men who had or developed symptoms. We do not know: Whether infected men who never develop symptoms can transmit Zika virus to their sex partners. How long Zika virus persists in the semen and if it is infectious (14-62 days) It is unknown if Zika is infectious in other body fluids exchanged by oral sex, including saliva and vaginal fluids. Traveling to an area with risk of Zika ( Men and women traveling in an area with risk of Zika should consider using condoms every time they have sex or not have sex while traveling. If a couple has a male partner and only he travels to an area with risk of Zika The couple should consider using condoms or not having sex for at least 6 months After the male partner returns, even if he doesn t have symptoms, or From the start of the male partner s symptoms or the date he was diagnosed with Zika. The couple should consider using condoms or not If a couple has a female partner and having sex for at least 8 weeks After the female partner returns from to an area with risk of Zika, only she travels to an area with risk of even if she doesn t have symptoms, or Zika From the start of the female partner s symptoms or the date she was diagnosed with Zika. The couple should consider using condoms( or If the couple contains both a male and not having sex for at least 6 months After returning female from an area with risk of Zika, even if they don t partner and both travel to an area with have symptoms, or From the start of either partner s symptoms or risk of Zika from the date either were diagnosed with Zika. If either partner develops symptoms of Zika or has concerns, they should talk to a healthcare provider. In Summary Assessment Identify Exposure history Primary screening/travel history Identify signs/symptoms Fever Joint Pain Conjunctivitis Muscle Pain Headache Infection Control Standard Precautions for body fluids such as blood, vaginal secretions, and semen Occupational exposure Clinical Interventions Supportive care for symptoms Patient education Testing Ultrasound Zika pregnancy hotline In Summary Notifiable condition Work with local health department Laboratory testing will not be completed during the ED visit Target education Follow up with OBGYN / pregnancy planning Caution about mosquito exposure Sexual exposure Treat immediate symptoms Use local health departments / CDC for updates and information. 7

8 Resources CDC Resources: Ready to use PDFs Pregnant? What we know and what we don t know about Zika Protecting from mosquitos Vector Control Living in endemic areas Travel considerations English and Spanish NACCHO Resources: chives/2267 Idaho Resources: Idaho Public Health Guidance for Zika Virus Testing Click.aspx?fileticket=543nCNML0k4%3D&t abid=111&portalid=0&mid=13808 Eastern Idaho Regional Medical Center information page Idaho Dept of Health and Welfare Click.aspx?fileticket=ksJ_ADf_GLg%3D&ta bid=111&portalid=0&mid=