Zika and other Flaviviruses

Transcription

1 Photo Credit: Zika and other Flaviviruses Charsey Cole Porse, PhD, MPH California Department of Public Health VectorBorne Disease Section Sharon Messenger, PhD California Department of Public Health Viral and Rickettsial Disease Laboratory October 18, 2016

2 Known Geographic Extent of Zika Virus from 1947 through 2006 Uganda

3 Zika Spreads to Pacific Islands 2007: First major outbreak of Zika on the island of Yap 185 suspect cases : Outbreak in French Polynesia 8750 reported cases; 74 with severe neurologic symptoms 2014: Cases reported from New Caledonia, Cook Islands, Easter Is. Easter Island

4 Countries, Territories and Areas with Autochthonous Zika Virus Circulation ( )

5 Zika Reported from Brazil In May 2015, an outbreak of Zika was identified in several northeastern states of Brazil; by December 2015, Zika had spread to 18 states. A retrospective analysis of positive dengue test samples found Zika positive results evident as early as February The virus may have been introduced into Brazil in 2014 by persons attending the World Soccer Cup or by members of a Polynesian team attending an international canoe race. In July 2015 Brazil reported an association between Zika virus infection and GuillainBarré syndrome In October 2015 Brazil reported an association between Zika virus infection and microcephaly. According to PAHO Brazil has reported just over 100,000 confirmed and nearly 200,000 suspect cases since the outbreak began in 2015.

6 Microcephaly and Zika Definition: Head circumference at birth <2 standard deviations below mean for gestational age and sex Causes: Congenital infection: e.g. syphilis, rubella, toxoplasmosis Genetic disorders and inherited mutations Other brain injury: hypoxia, drugs, toxins, FAS Outcomes: Range from normal to severe, including death Can include seizures, visual or hearing deficits Correlate with severity of microcephaly Epidemiology: 212/10,000 live births in US, 2/10,000 in California

7 Reported Microcephaly Cases in Brazil

8 Zika Virus is a Cause of Microcephaly

9 Microcephaly and Zika 9 confirmed cases of Zika virus in pregnant travelers All reported rash, 8 reported at least one other symptom 6 with symptoms in 1 st trimester: 2 fetal losses, 1 microcephaly, 2 terminations, 1 ongoing pregnancy 3 with symptoms in 2 nd and 3 rd trimester: 2 healthy infants and one ongoing pregnancy

10 Sexual Transmission of Zika Virus

11 National Center for Emerging and Zoonotic Infectious Diseases U.S. Men s Zika Virus Shedding Study Objective Determine the frequency, duration, and pattern of Zika virus shedding in semen and urine of infected symptomatic men Methods Men with confirmed infection enrolled at any time up to 6 months following illness onset Semen and urine selfcollected at home every 2 weeks for 6 months, sent directly by participant to CDC via overnight delivery Specimens tested by PCR and cell culture for viral isolation Results not reported to participants until the end of their participation (6 months after illness onset)

12 National Center for Emerging and Zoonotic Infectious Diseases Enrollment status as of 27 September 2016: 170 men from 21 States NYC U.S. Men s Zika Virus Shedding Study*** *** The locations shown are the participant s CURRENT state of residence. Some have moved (permanently or temporarily) from their original reporting state. NY state number includes NYC (53 enrolled).

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14 FDA Guidance on Zika and Blood Banks Revised Recommendations for Reducing the Risk of Zika Virus Transmission by Blood and Blood Components issued Aug 2016 Screen blood products for Zika virus using investigational individual donor nucleic acid test (IDNAT) Use pathogen reduction technology for platelets and plasma Discontinue donor screening questions If donor tests positive for Zika virus Defer for 120 days Quarantine all blood products collected from donor in prior 120 days

15 Modes of Zika Virus Transmission Mosquitoborne Congenital Sexual Care giving (rare) Blood transfusion

16 Zika and Risk of Local Transmission Primary vectors: Aedes aegypti & Aedes albopictus Typically disease of tropical and subtropical regions Increased outbreaks and case numbers worldwide Increased numbers of travelers becoming infected Increased risk of autochthonous transmission some U.S. states

17 Local Transmission of Dengue and Chikungunya in the U.S. Florida Reported 101 locally transmitted dengue cases since : 58 cases 2011: 7 cases 2012: 2 cases 2013: 24 cases 2014: 7 cases 2015: 1 case 2016: 2 cases (one FL Keys, one MiamiDade) 11 locally transmitted chikungunya cases in 2014 Texas Locally transmitted dengue cases corresponding to outbreak in northern Mexico 2005: 4 cases 2008: 1 case 2014: 24 cases 1st locally transmitted chikungunya case in November 2015

18 Local Zika Transmission in Florida 146 locally acquired Zika cases reported as October 10, 2016

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20 Travel Associated Zika in the United States, N= 3,

21 California Travel from ZikaAffected Countries Air Travel (2015) ~4.5 million travelers flew into CA from Zika affected areas Final destination airports: Los Angeles 54%, San Francisco 20%, San Diego 6% Highest travel volume to CA occurred in July and August 66.8% of flights originated in Mexico Sea Travel (Oct 2014 Sept 2015) 1.2 million travelers entered CA from Zika affected areas Arrival ports: Long Beach 65.1%, Los Angeles 20.2%, San Diego 8% Land Travel (2015) 55 million travelers entered CA from Zika affected areas California port of entries San Ysidro: 47.2%, Otay Mesa: 21.8%, Calexico 14%, Calexico East 12%

22 Confirmed Zika Cases in Mexico by State January 1, 2016 October 3, confirmed cases 1 25 confirmed cases Sonora confirmed cases Chihuahua confirmed cases Coahuila More than 100 confirmed cases Durango Nuevo León Ag. Yucatán Jalisco Tl. Data provided by the Mexican Ministry of Health KA_CASOS_SEM38_2016.pdf Colima Ag. = Aguascalientes Quer. = Querétaro DF = Distrito Federal Tl. = Tlaxcala Puebla Guerrero Oaxaca Morelos Tabasco Chiapas

23 Confirmed Dengue Cases in Mexico by State January 1, 2016 September 26, confirmed cases confirmed cases Sonora confirmed cases Chihuahua confirmed cases Coahuila More than 1000 confirmed cases Durango Nuevo León Ag. Yucatán Jalisco Colima Guerrero Tl. Puebla Campeche Tabasco /doctos/panodengue/panoramas_201 6/Pano_dengue_sem_38_2016.pdf Ag. = Aguascalientes Quer. = Querétaro DF = Distrito Federal Tl. = Tlaxcala Morelos Oaxaca Chiapas

24 Confirmed Chikungunya Cases in Mexico by State January 1, 2016 October 3, confirmed cases confirmed cases Sonora confirmed cases Chihuahua confirmed cases Coahuila More than 1000 confirmed cases Durango Nuevo León Nayarit Ag. Yucatán Jalisco Tl. ud.gob.mx/doctos/avisos/201 6/chik/DGE_CHIK_CASOSYDEF _SEM35_2016.pdf Ag. = Aguascalientes Quer. = Querétaro DF = Distrito Federal Tl. = Tlaxcala Colima Puebla Guerrero Oaxaca Morelos Tabasco Chiapas

25 Mosquitoborne Diseases in California Since 2003, only human cases of West Nile virus have been locally acquired in California Imported cases of dengue, chikungunya, Zika and malaria are reported in California The risk for local transmission of dengue, chikungunya, Zika has increased in California with the detection of Aedes aegypti and Aedes albopictus in 12 California counties.

26 TravelAssociated Cases of Dengue, Chikungunya and Zika in California, Dengue Chikungunya Zika * * * Number of cases Counties *As of October 7, 2016

27 TravelAssociated Cases of Dengue in California, cases from 23 counties 95 cases returned to counties with Aedes aegypti and/or Aedes albopictus mosquitoes 76% were likely viremic while in California 45% of cases had travelled to Latin America Mexico 17%, El Salvador 12% 32% of cases required hospitalization

28 TravelAssociated Dengue Cases in California, 2016* 1 No reported cases reported cases 1120 reported cases 21 reported cases County with Aedes mosquitoes 126 cases *as of October 7, 2016

29 TravelAssociated Cases of Chikungunya in California, cases from 30 counties 140 cases in cases returned to counties with Aedes aegypti and/or Aedes albopictus mosquitoes 53% were likely viremic while in California 91% of cases had travel to Latin America Mexico 40%, El Salvador 16%, Guatemala 13% 8% of cases required hospitalization

30 TravelAssociated Chikungunya Cases in California, 2016 No reported cases reported cases 1120 reported cases 1 21 reported cases County with Aedes mosquitoes 19 cases *as of October 7, 2016

31 Zika Infections in California, Zika cases reported in All associated with a person who traveled to a region with a known Zika outbreak 3 sexuallytransmitted case 214 (65%) were residents of counties with invasive Aedes 245 (75%) were potentially viremic while in California k

32 TravelAssociated Zika Cases in California Variable Value Total number 327 Percentage of female cases 64% Age range Median age 0 73 years 35 years Pregnant women 38 Asymptomatic pregnant women 18 (47%) Liveborn infants with birth defects 2

33 Zika Infections: Frequency of Symptoms Symptom Frequency of Symptom Rash 82% Fever 56% Joint pain 58% Conjunctivitis 30%

34 350 Number of TravelAssociated Cases of Zika in California by Week Reported, Previously reported cases New cases for the week /7/2016 9/30/2016 9/23/2016 9/16/2016 9/9/2016 9/2/2016 8/26/2016 8/19/2016 8/12/2016 8/5/2016 7/29/2016 7/22/2016 7/15/2016 7/8/2016 7/1/2016 6/24/2016 6/17/2016 6/10/2016 6/3/2016 5/27/2016 5/20/2016 5/13/2016 5/6/2016 4/29/2016 4/22/2016 4/15/2016 4/8/2016 4/1/2016 3/25/2016 3/18/2016 3/11/2016 3/4/2016 2/26/2016 2/19/2016 Week Reported

35 2 TravelAssociated Zika Cases in California No reported cases reported cases 1120 reported cases 21 reported cases County with Aedes mosquitoes 328 cases *as of October 7, 2016

36 TravelAssociated Cases of Zika in California, Top 10 Travel History Countries Country Number of Cases Mexico 85 Nicaragua 44 Guatemala 33 El Salvador 27 Dominican Republic 24 Puerto Rico 23 Honduras 18 Costa Rica 17 Jamaica 13 Colombia 6

37 Vectors Aedes aegypti (Yellow Fever Mosquito) Aedes albopictus (Asian Tiger Mosquito) Photograph: Courtesy Susan Ellis

38 CDC s Estimate of the potential range of Aedes aegypti and Aedes albopictus in the United States, 2016

39 Aedes aegypti and Aedes albopictus Mosquito Detections by County, California, * Aedes aegypti Aedes aegypti and Aedes albopictus Container Breeders San Mateo Alameda Tulare Kern San Bernardino Los Angeles Riverside *As of September 2016 San Diego Imperial

40 Enhanced Zika and Invasive Aedes Surveillance

41 Surveillance for Zika Virus and Invasive Mosquitoes MVCAC RTPCR to detect Zika virus in mosquitoes Viruses DENV CHIKV ZIKV WNV SLEV MALDITOF testing of Aedes eggs to identify species

42 CDPH Invasive Aedes Response Plan (2014) Contents Introduction on Aedes aegypti and Aedes albopictus mosquitoes and the exotic viruses they can transmit Recommended surveillance and response actions for local vector control agencies and health departments under four possible scenarios: Predetection of Aedes aegypti/albopictus Postdetection of Aedes aegypti/albopictus Detection of Aedes aegypti/albopictus positive for dengue or chikungunya before local human infection documented Detection of locally acquired human infection with dengue, chikungunya, or another exotic mosquitoborne virus Discussion of the recommended actions

43 Potential for local transmission is low A viremic person would need to return to a region where there are Aedes mosquitoes and be bitten by an Aedes that would live long enough to be come infectious and bite another person who then becomes infected Mitigating factors: Patchy Aedes aegypti and albopictus distribution in CA Use of AC, window and door screens Better water management than in other countries Good mosquito control If an outbreak were to occur, it would likely be limited in scope and duration Outbreaks of dengue and chikungunya elsewhere in the US have been contained Therefore the US is unlikely to experience the same extensive outbreaks currently being experienced in Latin America

44 Laboratory Diagnostic Testing for Zika Virus Why laboratory testing is crucial to diagnose Zika virus infections ()ssrna enveloped virus Family: Flaviviridae Genus: Flavivirus Other flaviviruses pathogenic to humans: dengue virus West Nile virus Japanese encephalitis virus Yellow fever virus Flaviviruses are genetically closelyrelated viruses Symptoms are similar (fever, rash, joint pain, conjunctivitis) seen in dengue and chikungunya virus infections Aedes aegypti is a primary vector for several emerging arboviruses as with dengue and chikungunya viruses They cocirculate e.g., Zika, dengue, and chikungunya viruses in the Americas

45 Challenges of Diagnostic Testing for Zika Virus: Rationale for the CDC Testing Guidance Acute dengue vs Zika virus infection 10 8 Viraemia IgG 10 3 IgM 80 Zika Dengue modified from Guzman, M. G. et al. Dengue: A continuing global threat. Nature Reviews Microbiology 8, S7 S16 (2010) Zika viraemia is lower and of shorter duration Viral loads <3.5 X 10 3 viral particles/ml compared to ~ for dengue and chikungunya (Lanciotti et al., 2008) Virus is often no longer detectable in serum at or shortly after symptom onset Most detections of Zika virus by RTPCR in serum: <3 days of illness onset Zikaspecific IgM can appear later in course of infection Samples collected <7 days after onset can be falsely negative Zika virus IgM may persist as long as dengue virus IgM (~12 weeks) little data For individuals with no symptoms (no onset date), 2 weeks after exposure was chosen to ensure that IgM should be detectable if infected with Zika virus.

46 Challenges of Diagnostic Testing for Zika Virus: Rationale for the CDC Testing Guidance from Lanciotti et al EID 14(8):12329 Flavivirusspecific antibodies (IgM & IgG) crossreact Neutralization studies (PRNT) illustrate complexity of the immune response in primary versus secondary flavivirus exposures Patient Days post onset ZIKV DEN1 DEN2 DEN3 DEN4 JEV YFV WNV SLEV MVEV 822a 822b a 830b a 849b a 862b a 817b a 833b a 844b a 955b 1 14 Primary: No previous flavivirus exposure Secondary: Previous flavivirus exposure Plaque Reduction Neutraliztion Test (PRNT)

47 CDC recommended tests for detection of Zika virus Type of Test PCR Preferred test in acute samples < 7 days post onset (serum) <14 days post onset (urine) IgM (CDC MAC ELISA) >3 days post onset Serology: Screening Serology: Confirmatory Neutralizing Antibodies Plaque Reduction Neutralization Test (PRNT) Compare titers between Zika virus and other flaviviruses

48 CDC Zika Testing Algorithm Symptomatic with International /Specific US Travel January 13, 2016 Serum must be collected < 12 weeks after symptom onset Serum Serum <7 days All samples (>3 days recommended) RTPCR* Zika/dengue/chikungunya IgM testing Zika/dengue/chikungunya Zika virus NEG NEG POS CONFIRMED ZIKA CASE Complete IgM testing before reporting * Negative Zika PCR does not rule out Zika virus infection NO IgM If <7 days, repeat convalescent serum ZIKA &/or DEN IgM Flavivirus PRNT CHIK IgM Alphavirus PRNT No IgM NEGATIVE

49 Evolution of CDC Laboratory Testing Guidance Initial CDC Lab Guidance Jan 13 CDC Update: Possible congenital Infection Jan 29 CDC Update: Asymptomatic Mar pregnant 25 Feb 5 & 7 CDC MAC ELISA EUA Feb 26 CDC Trio EUA Mar 17 CDC Update: Interpretation of PRNT Update expected May 31?? CDC Update: Urine PCR CDC Update: Increase PCR testing May 10 Jul Jan Feb Mar Apr May Jun Jul Aug Sep 2017 Possible congenital infection testing Zika & dengue IgM Zika & dengue RTPCR Added testing of asymptomatic pregnant women with travel Zika IgM only serum >212 weeks return of travel Added RTPCR testing of urine recognition that Zika viral RNA persists in urine longer than in serum urine PCR recommended <14 days of symptom onset Traditional use of >4 fold comparative titers no longer recommended PRNT titers are measured as present or absent confirmed or probable Zika virus infection requires Zika Ab neut POS/dengue Ab neut NEG CDC Revamped algorithms Increased emphasis on PCR testing (urine and serum) If IgM is positive or equivocal, reflex to PCR for pregnant women

50 Current CDC Laboratory Testing Guidance

51 Zika Virus Testing at CDPH Week 40 Total Cases Confirmed as of 10/01/16 (Statewide testing) Patients Received at VRDL 204 (228 specimens) Patients Tested at VRDL 273 (292 specimens) 5,593 (6,521 specimens) 5,315 (6,070 specimens) Zika virus lab confirmed/probable cases: (230 cases tested in VRDL) 2% 22% % of all patients tested that were labconfirmed Zika cases: Asymptomatic pregnant women: ~0.6% Symptomatic cases: 13.9% 76% Symptomatic Asymptomatic Pregnant Special Testing Viruses detected in symptomatic cases: (All cases) 208 Zika virus 51 dengue virus 10 chikungunya 5 flavivirus (DEN & ZIKA IgM & PRNT titers POS) 1% 4% 2% 10% 82% Negative Chikungunya Dengue Flavivirus Zika

52 Number of tests performed/ week by test type PRNT Zika Zika IgM Zika RTPCR Serum Zika RTPCR Urine CDC Week

53 D e l N o r t e H u m b o l d t T r i n i t y S i s k i y o u S h a s t a M o d o c L a s s e n Zika Testing Capacity in the CA PHL Network Updated 9/29/2016 M e n d o c i n o L a k e M a r i n G l e n n C o l u s a S o n o m a Y o l o N a p a S a n F r a n c i s c o S a n M a t e o S a n t a C r u z T e h a m a S o l a n o C o n t r a C o s t a B u t t e A l a m e d a S a n t a C l a r a S a n J o a q u i n P l u m a s S t a n i s l a u s M o n t e r e y S i e r r a P l a c e r E l D o r a d o M e r c e d A l p i n e T u o l u m n e M a r i p o s a F r e s n o K i n g s M o n o T u l a r e As of Oct 1, 2016: 551 patients tested 49 patients POS by PCR for Zika virus I n y o Singleplex rrtpcr Only Trioplex rrtpcr Only Both Trioplex rrtpcr and MACELISA Zika testing covered by another regional PHL Trioplex rrtpcr validated but not online S a n L u i s O b i s p o K e r n S a n t a B a r b a r a V e n t u r a L o s A n g e l e s Long Beach City O r a n g e S a n B e r n a r d i n o S a n D i e g o R i v e r s i d e I m p e r i a l

54 All Testing CDC Jan 13 VRDL IgM Mar 4 VRDL PCR Feb 23 County Labs begin PCR testing Apr 1 VRDL PRNT Mar 25 CDC MAC ELISA EUA Feb 26 CDC Trio EUA Mar 17 Quest PCR Apr 28 LabCorp PCR Jun 6 LabCorp IgM Aug 2 Quest IgM Sep Jan Feb Mar Apr May Jun Jul Aug Sep CDC VRDL LPHLs Commercial

55 Trends in tests performed/ week IgM vs PCR Zika IgM Local PHLs and commercial labs increase PCR testing CDC guidance emphasizes PCR testing CDC recommends urine PCR Zika RTPCR Serum Zika RTPCR Urine

56 Clinical Sensitivity of RTPCR on Serum vs Urine Detection of Zika virus RNA in blood vs urine specimens from Gourinat et al EID 21 (1):8486 VRDL 230 Zika probable and confirmed cases : Serum PCR: 149 patients Urine PCR: 96 patients IgM: 220 patients Test # positive % positive IgM 156/ % Serum PCR 76/149 51% Urine PCR 156/ %

57 Challenges of Diagnostic testing for Zika Virus RTPCR Sensitivity serum PCR is 51% Sensitivity of urine PCR is 90.62% Specificity of urine or serum PCR is 100% In the 9 Zika confirmed or probable cases in which urine PCR was NEG: IgM was positive in 6 cases Serum PCR was positive in 3 cases Clinical sensitivity of PCR in serum is relatively low, but in urine is high IgM Among symptomatic individuals, the false negative IgM rate is: 58% for samples collected <4 days 45.4% for samples collected < 7 days ~5.5% for samples collected >7 days False positive IgM rate: Symptomatic: 24.5% not confirmed Asymptomatic: 75.5% not confirmed Clinical sensitivity of IgM problematic < 7 days; lack of specificity requires PRNT PRNT confirmation Titers determined to be unreliable for accurate discrimination PRNT specificity is high with primary exposures; low with secondary exposures

58 Challenges of Diagnostic testing for Zika Virus Where do we go from here? There is a great need for more specific and more sensitive clinical diagnostic tests FDA has granted EUA authorization* for: 10 molecular tests to detect Zika virus RNA Some are designed to detect multiple arboviruses (Zika, dengue, chikungunya) Only 2 tests to detect Zika specific IgM CDC MAC ELISA InBios ZIKV Detect IgM Capture ELISA More IgM tests are expected to receive FDA EUA authorization soon EuroImmune EUA is pending EUROIMMUN AntiZika Virus ELISA (IgM) & EUROIMMUN AntiZika Virus ELISA (IgG) There are studies under way to evaluate a Zika IgG test Crossreactivity is expected to be greater than with IgM EuroImmune already incorporates IgG in their test New technologies are likely needed to see improvements in sensitivity and specificity *

59 More Information VRDL Resources VRDL Medical and Epidemiology Liaison Section, (510) Sharon Messenger, PhD California Department of Public Health Viral & Rickettsial Disease Laboratory

60 More Information California Department of Public Health (CDPH) Centers for Disease Control and Prevention (CDC) Pan American Health Organization (PAHO) Charsey Cole Porse, PhD, MPH California Department of Public Health, VectorBorne Disease Section