Acute Flaccid Myeli.s- AFM (and AFP, and polio, and )

Transcription

1 Acute Flaccid Myeli.s- AFM (and AFP, and polio, and ) VACCINE PREVENTABLE DISEASE UPDATE CHAS DEBOLT RN, MPH WASHINGTON STATE DEPARTMENT OF HEALTH IMMUNIZATION ACTION COALITION - WA OCTOBER 19, 2016

2 Eradicated (or almost eradicated) in the United States Smallpox 1946* Polio 1977* Diphtheria 1979* *Last case in WA Year

3 Defini.ons AFP Acute Flaccid Paralysis Clinical syndrome characterized by rapid onset of weakness in one or more limbs, progressing to maximum severity within several days to weeks. AFM Acute Flaccid Myeli1s An illness with onset of acute focal limb weakness and a magne>c resonance image (MRI) showing spinal cord lesion largely restricted to gray mader and spanning one or more spinal segments.

4 Defini.ons Poliomyeli1s polios: gray myelos: marrow/spinal cord Asymptoma>c infec>on, abor>ve polio, asep>c meningi>s Flaccid paralysis (1:200) Eliminated from western hemisphere since 1991 Last case in WA in 1977 (VAPP in 1993) Endemic in Afghanistan and Pakistan (20 and 54 cases in 2015)

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6 OPV and IPV OPV Live, adenuated Induces serum and intes>nal immunity Stops person to person transmission Passive immuniza>on VAPP - cvdpv IPV Inac>vated Not intes>nal immunity Does not stop transmission No VAPP

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8 Global (AFP) Surveillance

9 AFP, AFM, Polio??? Acute Flaccid Paralysis- AFP (rapid onset of limb weakness) Acute Flaccid Myelitis- AFM (AFP + gray matter abnormalities or CSF pleocytosis) Other AFP (Does not meet AFM criteria) Poliovirus (Wild or vaccineassociated) Poliomyelitis Enterovirus -Coxsackieviruses A and B -Echovirus -Enterovirus D68, 70, 71 -Rhinovirus Herpesvirus -Cytomegalovirus -Epstein-Barr virus Flavivirus -West Nile Virus -Japanese encephalitis -St. Louis encephalitis Adenovirus Viruses Rabies Varicella zoster HIV Some arboviruses Paramyxovirus -Parainfluenza -Mumps Other conditions Guillain-Barre Botulism Diphtheria Acute transverse myelitis Myasthenia gravis Polyomyositis Trichinosis Lyme borreliosis Tick bite paralysis Spinal cord compression Epidural abscess Plant and snake toxins

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11 AFM in the United States Between August 2014 and July 2015, CDC verified reports of 120 children in 34 states with AFM. Median age : 7 years Almost all of them were hospitalized.

12 The Washington Post September 21 at 11:30 AM A mysterious polio-like illness that paralyzes people may be surging this year.

13 AFM in Washington State 3 cases reported in the fall of Coxsackie virus A16 was found in two stool samples of one of the pa>ents tested at CDC. The other two cases tested nega>ve for enteroviruses. No AFM cases were iden>fied in Washington in 2015 in any age group. 1 probable AFM case in 2016

14 Objec.ves of surveillance To assure sensi>ve poliomyeli>s surveillance in Washington State To describe the epidemiology and baseline incidence of AFM and its poten>al causes To integrate AFM and polio surveillance ac>vi>es to increase sensi>vity and specificity of epidemiologic surveillance for these condi>ons

15 New WA State guidelines to integrate polio and AFM surveillance: Viruses other than polio virus known to be associated with AFM Agent Enteroviruses (polio and non-polio) West Nile Virus Japanese encephalitis virus Saint Louis encephalitis Cytomegalovirus Epstein-Barr virus Adenovirus Reservoir Humans, usually asymptomatic Bird reservoir: corvids. Vector: Culex mosquitoes Pigs and wild birds. Vector: Culex mosquitoes Wild birds and domestic fowl. Vector: Culex mosquitoes Humans, CMV strains found in animal species are not infectious for humans Humans. EBV will stay latent in a person for their lifetime Humans. Ubiquitous in the environment where contamination by human feces or sewage has occurred.

16 Tests available at PHL Specimen Pathogen Preferred test Test available at PHL CSF Respiratory Enterovirus PCR None West Nile Virus PCR/IgM IgM by MIA (Microsphere immunoassay) Herpes Simplex PCR/Culture Culture Cytomegalovirus PCR None Enterovirus/ Rhinovirus PCR None Adenovirus PCR Culture Influenza virus PCR PCR Serum West Nile Virus PCR/IgM IgM by MIA Stool Poliovirus PCR/Culture None Enterovirus (nonpolio) PCR None

17 Pregnancy- related Tdap recommenda1ons ACIP Recommenda1on Date of ACIP Vote Date Published Tdap post- partum plus Tdap for close family members/contacts of infant Tdap during pregnancy (ideally a_er 20 weeks gesta>on) for women previously unvaccinated (one- >me dose) Tdap during third trimester each pregnancy October 26, 2005 December 15, 2006 June 22, 2011 October 21, 2011 October 24, 2012 February 22, 2013

18 Reported Mumps Cases and Outbreaks in the U.S., Jul 2010-Dec 2015 (n=4,289) Outbreak Cases ( 20) Cases 2500 Number of Cases Year *Some outbreaks overlap years, all cases were counted in the first year for those outbreaks *NNDSS and NCIRD data, last accessed Aug 29 th, 2016

19 U.S. Mumps Cases by Epi Week, Jan-Jul 2016 (n=1,773) Case Count Jan Feb Mar Apr May Jun Jul Week *NNDSS and NCIRD data, last accessed Aug 29 th, 2016

20 q Age range: >1 yr to 88 yrs old Median age: 21 yrs U.S. Mumps Cases, Jan-Jul 2016 q 76% reported vaccination status 95% (1280) vaccinated 68% (832) 2 or more doses q 20 reported outbreaks ( 3 or more cases) 18 in University settings 2 currently on-going NNDSS data, collected Aug 26 th, 2016

21 Mumps in Vaccinated People During mumps outbreaks in highly vaccinated communi1es: The propor>on of cases that occur among people who have been vaccinated may be high This should not be interpreted as meaning that the vaccine is not effec>ve. Vaccine effec>veness is assessed by comparing 1. the adack rate in people who are vaccinated with 2. the adack rate in those who have not been vaccinated. People who have not been vaccinated against mumps usually have a much greater mumps adack rate than those who have been fully vaccinated.

22 Vaccina.on and Mumps Outbreak: an Example Let s say an outbreak occurs among 1,000 people 950 of these 1,000 people have received two doses of the vaccine and 50 are unvaccinated (i.e., vaccine coverage is 95%). If there is a 30% adack rate among unvaccinated people, 15 of the 50 unvaccinated people would get the disease. If there is a 3% adack rate among the 950 vaccinated people, 29 vaccinated people would get the disease. Therefore, of the 44 people who got sick during the outbreak, the majority (29, or 66%) would have been vaccinated. People who hadn t been vaccinated were 10 >mes more likely to get sick as those who had been vaccinated,

23 A^ack rates and Vaccine Effec.veness If none of the 1,000 people had been vaccinated, the outbreak would have resulted in 300 cases rather than only 44. In this scenario, we would say that the vaccine is 90% effec>ve in preven>ng the disease a_er two doses This is the same as saying that the adack rate in the unvaccinated group is 10 >mes higher than the adack rate among people who have received two doses of vaccine. The formula to calculate vaccine effec>veness is (adack rate in unvaccinated group minus adack rate in vaccinated group) divided by adack rate in unvaccinated group, or ARU- ARV ARU

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25 Chas DeBolt RN, MPH Senior Epidemiologist for Vaccine Preventable Diseases Washington State Department of Health 1610 NE 150 th Street Shoreline, WA (206)

26 Number of cases (confirmed and probable) # Cases Rate per 100, st 3 rd DTaP Pediatric Pertussis Cases by Age th DTaP 5th DTaP Acellular Only Tdap Transition Year Whole cell & Acellular Age (years) Cases per 100,000 popula1on

27 Number of cases (confirmed and probable) # Cases Rate per 100, Pediatric Pertussis Cases by Age st 3 rd DTaP 4th DTaP 5th DTaP Acellular Only Tdap Transition Year Whole cell & Acellular Age (years) Cases per 100,000 popula1on

28 Pediatric Pertussis Cases by Age 2014 # Cases Rate per 100,000 Acellular Only Transition Year Whole cell & Acellular Number of cases (confirmed and probable) st 3 rd DTaP 4th DTaP 5th DTaP Tdap Age (years) Cases per 100,000 popula1on

29 Pediatric Pertussis Cases by Age 2015 YTD # Cases Rate per 100,000 Acellular Only Transition Year Whole cell & Acellular Number of cases (confirmed and probable) st 3 rd DTaP 4th DTaP 5th DTaP Tdap Age (years) Cases per 100,000 popula1on