west nile virus michigan - 2002
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West Nile Virus Michigan - 2002. Mary Grace Stobierski, DVM,MPH,DACVPM Michigan Dept. Community Health. West Nile Virus 2002, A Season of Surprises. Largest arbovirus meningoencephalitis outbreak epidemic ever documented in western hemisphere Largest WNME epidemic ever documented - PowerPoint PPT PresentationTRANSCRIPT
West Nile VirusMichigan - 2002
Mary Grace Stobierski, DVM,MPH,DACVPMMary Grace Stobierski, DVM,MPH,DACVPM
Michigan Dept. Community HealthMichigan Dept. Community Health
West Nile Virus 2002, A Season of Surprises Largest arbovirus meningoencephalitis Largest arbovirus meningoencephalitis
outbreak epidemic ever documented in outbreak epidemic ever documented in western hemispherewestern hemisphere
Largest WNME epidemic ever documentedLargest WNME epidemic ever documented Geographic spread to the Pacific CoastGeographic spread to the Pacific Coast Clinical syndromes (Acute Flaccid Clinical syndromes (Acute Flaccid
Paralysis, was not Guillian-Barre syndrome)Paralysis, was not Guillian-Barre syndrome) New modes of transmissionNew modes of transmission
Novel Modes of West Nile Virus Transmission, 2002 Transplanted organsTransplanted organs Transfused bloodTransfused blood Breast milkBreast milk Percutaneous, occupational exposurePercutaneous, occupational exposure Prenatal transmissionPrenatal transmission
WNV Hotline Calls* 2002 (operated by MDCH staff)
0
5000
10000
15000
20000
25000
July August September
# calls
1/888/668-0869
* >35,000 calls in Aug & Sept
Michigan Department of Community Health Announces Probable Human Cases of West Nile Virus August 16, 2002 Michigan Department of Community Health Chief Medical Executive, David R. Johnson M.D., todayannounced two probable human cases of West Nile virus. Laboratory samples have been sent to the Centers for Disease Control and Prevention for confirmatory testing. The first case involves an 82 year-old male from Southeast Michigan who was hospitalized and hasbeen released in good condition. The second involves a 63 year-old male from Southeast Michiganwho is currently hospitalized and appears to be improving.
“We are encouraged that both of these gentlemen appear to be recovering and we will continue to workwith health care providers throughout Michigan to quickly identify any other potential human cases,” said Dr. Johnson. “The most important thing a person can do to protect themselves from West Nile virus is to follow the common-sense precautions to minimize exposure to mosquitoes.”
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50
100
150
200
250
300
350
0
5
10
15
20
25
30
35
Phone Calls Human Cases
Phone Reports of Dead Birds versus Human Cases in Michigan for 2002
Data from 614 out of 644 human cases
0
5
10
15
20
25
30
35
Onset Date
Nu
mb
er o
f C
ases
Confirmed Probable
Onset Date of Symptoms Among Human West Nile Virus Cases in Michigan for 2002
Data from 614 of the 644Total Cases
WNVHuman cases Michigan 2002*
644 cases51 deaths *(Total Cases/Deaths)
(Includes probable andconfirmed cases, all clinicalsyndromes)
Michigan WNV Case Statistics:
All CasesAll Cases
Age range: 9mo-95yrsAge range: 9mo-95yrs
Ave Age: 57.6Ave Age: 57.6
% Female: 45% Female: 45
% Male: 55% Male: 55
DeathsDeaths
Age range: 24-95 yrsAge range: 24-95 yrs
Ave Age: 74.5Ave Age: 74.5
% Female: 41% Female: 41
% Male: 59% Male: 59
West Nile Virus Case Summary
Total Laboratory Positive Cases: 644 West Nile Meningo-encephalitis cases: 559 (87%) Age range: .75-95 yrs Average age: 57.8 yrs West Nile Fever cases: 57 (9%) Age range: 3-80 yrs Average Age: 47.7 yrs Unknown cases: 28 (4%) Deaths: 51 (9%) Age range: 24-95 yrs Average age: 74.5 yrs
2002 Cases by Agegroup - 2002
0
20
40
60
80
100
120
140
< 10yrs
11-20yrs
21-30yrs
31-40yrs
41-50
yrs
51-60yrs
61-70yrs
71-80yrs
81-90yrs
> 90yrs
# CASES
N=639 cases
Additional Arboviruses in 2002
St. Louis Encephalitis: 3 casesSt. Louis Encephalitis: 3 cases Eastern Equine Encephalitis: 6 casesEastern Equine Encephalitis: 6 cases LaCrosse Encephalitis: 11 casesLaCrosse Encephalitis: 11 cases Powassan virus: 1 case (Emmet Co.) Powassan virus: 1 case (Emmet Co.)
(tick borne encephalitis)(tick borne encephalitis)
First time ever documented case inFirst time ever documented case in
Michigan! Michigan!
Additional Arbovirus CasesMichigan, 2002
CountyCounty SLESLE EEEEEE LACLAC POWPOW
ClareClare 11
EatonEaton 11
EmmetEmmet 11
GeneseeGenesee 33
HuronHuron 11
KentKent 11
MacombMacomb 22 11
ManisteeManistee 11
OaklandOakland 11 22
OttawaOttawa 11
PresquePresque
IsleIsle
11
WayneWayne 22 22
West Nile Virus Infection in an Organ Donor West Nile Virus Infection in an Organ Donor and Four Transplant Recipientsand Four Transplant Recipients
(GA & FL) August 2002(GA & FL) August 2002
Organ Donor
WNV PCR –IgM –
Organ Donor
WNV PCR +
Culture +IgM –
Kidney recipientWNME (fatal)
Kidney recipientWNME
Liver recipientWNF
Heart recipientWNME
Blood Blood components components
from 63 from 63 donorsdonors
Transfusion-associated West Nile virus infectionTransfusion-associated West Nile virus infection
BackgroundBackground
• Potential transmissionPotential transmission- Transient viremia- Transient viremia- Most infections asymptomatic- Most infections asymptomatic
• ““Small but not zero” riskSmall but not zero” risk- No chronic carriers- No chronic carriers- No cases reported in prior years or - No cases reported in prior years or
fromfrom endemic countries endemic countries
• Estimated risk: Estimated risk: 1.8-2.7/10,000 donations in 1.8-2.7/10,000 donations in 1999 Queens (NYC) epidemic1999 Queens (NYC) epidemic
Transfusion investigations in MI
Case #Case # AgeAge # Donors# Donors Underlying Underlying ConditionCondition
OutcomeOutcome
11 4747 3939 Liver Liver transplanttransplant
AliveAlive
22 4040 22 ObstetricObstetric AliveAlive
33 4444 44 Organ donorOrgan donor FatalFatal
44 1212 8383 LeukemiaLeukemia AliveAlive
55 7272 1010 CABGCABG FatalFatal
66 4343 Stem Cell Stem Cell TransplantTransplant
Not WNVNot WNV
77 5151 7979 LeukemiaLeukemia FatalFatal
88 7878 1010 MIMI FatalFatal
Transfusion investigations in MI, cont’dCase #Case # AgeAge # Donors# Donors Underlying Underlying
ConditionConditionOutcomeOutcome
99 7676 88 CancerCancer FatalFatal
1010 8080 88 DementiaDementia Not WNVNot WNV
1111 2626 1717 LeukemiaLeukemia AliveAlive
1212 6969 -- Blood DonorBlood Donor AliveAlive
1313 7575 44 CABGCABG AliveAlive
1414 77 1313 CancerCancer AliveAlive
1515 7373 2121 Co-recipientCo-recipient AliveAlive
CDC Protocol: Investigation of transfusion-CDC Protocol: Investigation of transfusion-associated West Nile virus infectionassociated West Nile virus infection
• Comprehensive chart review of caseComprehensive chart review of case
• Determine number & type of components transfused Determine number & type of components transfused to recipient in 4 weeks before WNV illness onsetto recipient in 4 weeks before WNV illness onset
Retrieve “initial donation samples” (retention Retrieve “initial donation samples” (retention segments, untransfused product, NAAT tubes)segments, untransfused product, NAAT tubes)
Test for WNV RNA (TaqMan rtPCR) and IgM Test for WNV RNA (TaqMan rtPCR) and IgM antibody (ELISA)antibody (ELISA)
• Donor F/U serum questionnaire & serum sample for Donor F/U serum questionnaire & serum sample for WNV IgM antibody testWNV IgM antibody test
• F/U questionnaire & WNV IgM antibody testing of F/U questionnaire & WNV IgM antibody testing of “other recipients” who received “suspect” blood “other recipients” who received “suspect” blood product (if indicated)product (if indicated)
Case definition: Confirmed transfusion-Case definition: Confirmed transfusion-associated West Nile virus infectionassociated West Nile virus infection
• Probable/confirmed WNV illness* in blood product Probable/confirmed WNV illness* in blood product recipientrecipient
• Transfusion within 4 weeks of illness onsetTransfusion within 4 weeks of illness onset
• Evidence of viremia in donor:Evidence of viremia in donor:TaqMan-positiveTaqMan-positive index donation sample(s) index donation sample(s)
ANDAND virus isolation virus isolationOROR
TaqMan-positiveTaqMan-positive index donation sample(s) index donation sample(s)ANDAND seroconversion in donor seroconversion in donor
* CDC. Epidemic/Epizootic West Nile Virus in the United States: * CDC. Epidemic/Epizootic West Nile Virus in the United States: Revised Guidelines for Surveillance, Prevention, and Control, April Revised Guidelines for Surveillance, Prevention, and Control, April 2001.2001.
First 3 MI cases are relatedMI 001MI 001 MI 002MI 002 MI 003MI 003
47yr,Wayne47yr,Wayne 40yr, Macomb40yr, Macomb 44yr, 44yr, Wayne/OaklandWayne/Oakland
Liver transplant; Liver transplant; recoveredrecovered
Obstetric; Obstetric; healthy infanthealthy infant
Liver donor; Liver donor; deceaseddeceased
CSF WNV +CSF WNV + CSF WNV +CSF WNV + All tissues All tissues WNV -WNV -
One blood One blood component component w/MI 002w/MI 002
One blood One blood component component w/MI 001w/MI 001
Donor to MI Donor to MI 001; but,not the 001; but,not the source of WNVsource of WNV
MI 0001 & MI 0002 Found to have one blood component in commonFound to have one blood component in common
Blood component in common found to be Taqman Blood component in common found to be Taqman PCR positive @ CDCPCR positive @ CDC
Donor of blood traced; Wayne county resident; Donor of blood traced; Wayne county resident; reported symptoms 3 days post-donationreported symptoms 3 days post-donation Fever, rash, myalgia, minor weakness. Fever, rash, myalgia, minor weakness.
Recovered 6-7 days later. Blood sample Recovered 6-7 days later. Blood sample 10/7/02 IgM + at CDC10/7/02 IgM + at CDC..
MI 0002 cont’d
Breast milkBreast milk Sample collected 9/19: Taqman +, IgM +, Sample collected 9/19: Taqman +, IgM +,
IgG +; Viral culture - at CDCIgG +; Viral culture - at CDC Sample collected 9/27: Taqman -, IgM +Sample collected 9/27: Taqman -, IgM +
Infant test resultsInfant test results Serum collected 9/27: IgM + Serum collected 9/27: IgM + (MDCH & CDC)(MDCH & CDC)
PKU card: Taqman - (MDCH)PKU card: Taqman - (MDCH)
MI 0002 cont’d
Mother reported infant had little outdoor or other Mother reported infant had little outdoor or other exposure to mosquitoesexposure to mosquitoes
Presence of measurable WNV-specific IgM Presence of measurable WNV-specific IgM suggests independent IgM production by infant as suggests independent IgM production by infant as result of WNV infection via breast milkresult of WNV infection via breast milk
No change in breastfeeding recommendationsNo change in breastfeeding recommendations
MI0004 Case Detail
12 year old, AML12 year old, AML
Had been in isolation at hospital for 65 continuous Had been in isolation at hospital for 65 continuous daysdays
Received 83 blood componentsReceived 83 blood components
No mosquito exposure, thus only means of No mosquito exposure, thus only means of transmission was via blood transfusiontransmission was via blood transfusion
Transfusion Investigations:Michigan Summary
15 Investigations15 Investigations
Patients: 7 yr – 80 yrPatients: 7 yr – 80 yr Includes 2 donors (1 organ and 1 blood)Includes 2 donors (1 organ and 1 blood)
# Blood Components: 2 – 83# Blood Components: 2 – 83
5 Fatal5 Fatal
2 Subsequently ruled out as WNV2 Subsequently ruled out as WNV
West Nile virus infections in blood transfusion West Nile virus infections in blood transfusion recipients, US Summaryrecipients, US Summary
61 possible cases reported to CDC since Aug 28, 200261 possible cases reported to CDC since Aug 28, 2002
19 19 notnot transfusion-associated WNV transfusion-associated WNV
21 had inconclusive investigations21 had inconclusive investigations
23 confirmed cases of transfusion-associated transmission23 confirmed cases of transfusion-associated transmission
Aged 7-90 yearsAged 7-90 years
12 Female; 11 Male12 Female; 11 Male
10 were immunocompromised10 were immunocompromised
Prevention of Transfusion-Related Infection Current: donor screeningCurrent: donor screening FDA encouraging development of nucleic acid-FDA encouraging development of nucleic acid-
based screening testsbased screening tests Will pooled nucleic acid testing have Will pooled nucleic acid testing have
high enough sensitivity?high enough sensitivity?Can these tests, if developed, be Can these tests, if developed, be
implemented in time for the 2003 season?implemented in time for the 2003 season? Retrieval & quarantine of blood products Retrieval & quarantine of blood products
collected during 2002 epidemic periodcollected during 2002 epidemic period
Intrauterine WNV InfectionNew York, August 2002 20 yr old in 2720 yr old in 27thth week of pregnancy week of pregnancy
Fever, H/A, blurred vision, vomiting, Fever, H/A, blurred vision, vomiting, abdominal & back pain, severe weakness.abdominal & back pain, severe weakness.
5 weeks later, delivered a live infant; has a 5 weeks later, delivered a live infant; has a number of congenital abnormalities.number of congenital abnormalities.
Mother: serum & CSF IgM +Mother: serum & CSF IgM + Infant: serum & CSF IgM +Infant: serum & CSF IgM +
MMWR Vol.51/No.50MMWR Vol.51/No.50
Laboratory-Acquired WNV
2 laboratory workers2 laboratory workers Percutaneous inoculationPercutaneous inoculation Illnesses in both: mild & self-limitingIllnesses in both: mild & self-limiting
Serum IgM (+) in both casesSerum IgM (+) in both cases
MMWR Vol 51/ No 50MMWR Vol 51/ No 50
West Nile virus, 2002:Emerging issues
Emergence in western U.S.Emergence in western U.S. New modes of transmissionNew modes of transmission
Breast milkBreast milk TransplacentalTransplacental Transfusion / transplantation Transfusion / transplantation Laboratory/occupationalLaboratory/occupational
Emerging clinical syndromesEmerging clinical syndromes WN feverWN fever WNME / acute flaccid paralysis WNME / acute flaccid paralysis WNME / rhabdomyolysisWNME / rhabdomyolysis
Long-term outcome studiesLong-term outcome studies
2002 SEASON CHALLENGES
Coordination between multiple agenciesCoordination between multiple agencies
Deluge of human case appearancesDeluge of human case appearances
Rapid communication of results to multiple partiesRapid communication of results to multiple parties
New modes of transmission discoveredNew modes of transmission discovered