Measles. CLINICAL CASE DEFINITION An illness characterized by all of the following: CASE CLASSIFICATION Suspect: Rash illness with fever

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1 CLINICAL CASE DEFINITION An illness characterized by all f the fllwing: Measles a generalized rash lasting at least 3 days AND a temperature f 101 F (38.3C) r higher AND at least ne f: cugh, cryza (runny nse), r cnjunctivitis (redness and inflammatin f the cnjunctiva which lines the eyelid and cvers the eyeball) CASE CLASSIFICATION Suspect: Rash illness with fever Prbable: A case that meets the clinical case definitin, has nn-cntributry r n serlgic r virlgic testing, and is nt epidemilgically linked t a cnfirmed case. Cnfirmed: A case that is labratry cnfirmed (see LABORATORY CONFIRMATION, belw), r that meets the clinical case definitin AND is epidemilgically linked t a cnfirmed case. A labratry-cnfirmed case des nt need t meet the clinical case definitin. TRANSMISSION Persn-t-persn via airbrne transmissin r drplets frm the respiratry secretins f infected persns. Drplets can becme aerslized and remain suspended in the air fr an extended perid f time (dcumented up t 2 hurs). Measles is highly cmmunicable. INCUBATION PERIOD Frm expsure t prdrme (symptms preceding rash) the average incubatin is days. Frm expsure t rash nset the average is 14 days (range 7 18). See Measles Timeline, belw. PERIOD OF COMMUNICABILITY Frm 4 days befre rash nset t 4 days after. REPORTING/INVESTIGATION Health care prviders shuld immediately reprt any pssible case f measles t lcal health department f the patient s residence. Lcal health department respnsibilities: Cntact case/guardian and health care prvider. Determine if case meets clinical case definitin. If definitin met (prbable r cnfirmed cases), investigate using reprt frm/surveillance wrksheet and cntrl guidelines belw. Measles is an imprtant public health cncern; if clinical presentatin suggests a likely measles case(s), ntify MDHHS Immunizatin Divisin by phne 517/ Reprt/ensure reprting f case t the Michigan Disease Surveillance System (MDSS). Page 1 f 8

2 CDC Measles Surveillance Wrksheet may be helpful in field investigatin t cllect and capture data. Obtain immunizatin histry infrmatin frm prvider recrd r MI Care Imprvement Registry (MCIR - state immunizatin registry). Update the MDSS recrd in a timely manner with new r additinal inf as it becmes available. Finalize MDSS recrd when case investigatin is cmplete. In the event f a measles-related death, btain and send cpies f hspital discharge summary, death certificate, and autpsy reprt t MDHHS Immunizatin Divisin. LABORATORY CONFIRMATION Essential; shuld be attempted fr all ptential cases meeting the clinical case definitin. Cllect serum and viral specimen (thrat swab, urine, etc). Labratry cnfirmatin fr measles is defined as ne f the fllwing: Psitive serlgic test fr measles-specific IgM antibdy (this is the preferred cnfirmatin) NOTE: Measles IgM tests that are negative and were cllected less than 72 hurs after the rash nset shuld be repeated using sera cllected 72 r mre hurs after rash nset. Significant rise in measles IgG antibdy by any standard serlgic assay Cllectin f sera fr these paired assays shuld be apprpriately spaced: 10 r mre days shuld separate the cllectin f the acute and cnvalescent sera. Sera shuld be tested in parallel (i.e., run tgether in the same test/assay batch). Islatin f measles virus frm a clinical specimen. Detectin f measles-virus-specific nucleic acid by plymerase chain reactin (PCR). Serum and viral (culture, PCR testing fr virus RNA and sequencing) specimens shuld be cllected frm suspected cases. See additinal infrmatin under LABORATORY SPECIMENS: PROCEDURES AND CONSIDERATIONS, belw. Measles testing is available thrugh the MDHHS labratry but is subject t reagent availability. Preapprval arrangements must be made thrugh the MDHHS VPD Surveillance Crdinatr at 517/ Measles testing (serlgic and virlgic) is als available thrugh cmmercial clinical labratries. IMMUNITY/SUSCEPTIBILITY Individuals shuld be cnsidered immune (prtected against) measles nly if they meet ne r mre f the fllwing cnditins: Brn befre 1957 (exceptins are wmen wh might becme pregnant and health care wrkers; these grups shuld have dcumentatin f immunity by ne f the methds immediately fllwing belw) Labratry cnfirmatin f a measles disease diagnsis; Serlgic (lab) evidence f immunity t measles Dcumentatin f receipt f 2 dses f measles-cntaining vaccine administered at least 28 days apart (1 dse is acceptable fr preschl-age children and adults nt cnsidered at high risk, ie. Page 2 f 8

3 adults wh d nt wrk in healthcare, wh d nt travel internatinally, and wh are nt students at pst-high schl educatinal institutins). NOTE: All persns wh wrk in a health care setting in any capacity shuld have evidence f immunity t measles, mumps, rubella, varicella, pertussis, hepatitis B, and seasnal influenza. CONTROL MEASURES Investigate reprts f pssible measles immediately. If Clinical Case Definitin is met, regard as true measles case; implement cntrl actins unless measles is ruled ut by lab testing r ther infrmatin. Cases shuld be excluded and islated frm grup activity settings (e.g. schls, day-care centers, wrk place, camps, etc.) immediately and thrugh the 4th day after the nset f rash t limit further expsures. In health care settings, use f Airbrne Precautins is recmmended. Identify expsed cntacts. Measles is highly cmmunicable. Measles cases are cmmunicable (cntagius) starting 3-5 days befre rash nset thrugh the 4th day after rash nset; expsure includes husehld cntact and same-rm cntact. Assess susceptibility f cntacts (see Immunity/Susceptibility, abve). Measles vaccine is universally recmmended as part f the rutine childhd immunizatin schedule, thus persns 4 years f age and brn after 1956 shuld have a histry f 2 dses f MMR vaccine, and persns 1 year and <4 years f age shuld have a histry f at least 1 dse f MMR vaccine. Susceptible cntacts shuld be recmmended t receive pst-expsure prphylaxis with either: Measles (MMR) vaccine, if given within 72 hurs f expsure Immune glbulin (IG), if given within 6 days f expsure Cmment: In mst situatins vaccine is preferable t use f immune glbulin, prvided vaccine can be given within 72 hurs. Hwever, IG, rather than vaccine, shuld be used fr infants under 6 mnths f age, pregnant wmen, and severely immuncmprmised persns: Infants aged <12 mnths wh have been expsed t measles shuld receive 0.5 ml/kg [0.11ml/lb] f bdy weight f IG given intramuscularly (IGIM) (maximum dse = 15 ml). Alternatively, MMR vaccine can be given instead f IGIM, t infants age 6 11 mnths, if it can be given within 72 hurs f expsure. Pregnant wmen withut evidence f measles immunity wh are expsed t measles shuld receive 400 mg/kg f IG given intravenusly (IGIV). Severely immuncmprmised persns wh have been expsed t measles shuld receive 400 mg/kg f IG given intravenusly (IGIV), even if they have past evidence f measles immunity Other peple wh d nt have evidence f measles immunity can receive an IG dse f 0.5 ml/kg f bdy weight. Give pririty t peple wh were expsed t measles in settings where they have intense, prlnged clse cntact (e.g., husehld, child care, classrm, etc.). Give IG intramuscularly; the maximum dse is 15 ml. Exclusin f expsed, susceptible cntacts: Expsed persns attending grup-activity settings (e.g. schls, day-care centers, wrk place, camps) wh cannt prvide dcumentatin f Page 3 f 8

4 measles immunity (including thse with medical, religius and philsphical exemptins) shuld be vaccinated as sn as pssible. Thse wh are receiving their 1 st dse f measles vaccine (MMR r MMRV) and are receiving it within 72 hurs f expsure t measles may in general be re-admitted t the activity setting (hwever the lcal health fficer may pt nt t grant readmissin until 21 days after the last knw case nset, depending n the situatin). The 2 nd dse f measles vaccine in shuld be scheduled fr 28 days after the first dse. Thse wh had received ne dse f measles-cntaining vaccine prir t the expsure and wh nw receive a secnd dse fllwing the expsure d nt need t be excluded frm public settings r grup activities. Thse wh refuse vaccinatin, and thse wh receive vaccine mre than 72 hurs after expsure, shuld be excluded frm the setting fr 21 days after the nset f the final case f measles in the grup activity utbreak setting. Althugh the 2 nd dse f measles, mumps, rubella vaccines is nt rutinely given until 4 6 years f age, in utbreak situatins invlving day care, pre-schl, and ther settings with children under 4 years f age, cnsideratin shuld be given t requiring the 2 nd dse as a cntrl measure, fllwing apprpriate minimum intervals between dses. Prvide infrmatin abut measles t persns at risk and/r the general public. An excellent Questin-&-Answer measles infrmatin sheet in.pdf frmat is available frm the Immunizatin Actin Calitin ( ) LABORATORY SPECIMENS: PROCEDURES AND CONSIDERATIONS Cllect a serum and specimen(s) fr PCR/viral islatin/mlecular epidemilgy testing (a respiratry specimen, such as thrat r naspharyngeal swab; urine can als be cnsidered). Cllect specimens at the same time. See belw fr details. Labratry supprt fr measles case investigatins fulfills 2 imprtant and distinct bjectives: 1) cnfirmatin f cases which imprves verall surveillance 2) characterizatin f circulating measles virus strains It is imprtant t pursue bth serlgic and virlgic testing; i.e., it is imprtant t cllect bth serum and viral specimens frm suspected cases. T btain MDHHS serlgy and virlgy specimen cllectin and cntainer kits, call MDHHS Labratry Supprt Unit: MEASLES SEROLOGY Purpse: t cnfirm a case f measles by detecting measles-specific antibdies. Specimen needed: serum, 2 ml. MDHHS lab kit: unit 8 Specimen cntainer descriptin: plastic serum tube with skirted cap MDHHS lab frm: DCH-0583 Page 4 f 8

5 Preferred test: measles IgM antibdy. This test is available at r thrugh MDHHS labratry, using highly sensitive and highly specific direct capture ELISA (EIA) methdlgy. Alternate tests: ther methds f measles IgM; paired IgG demnstrating significant rise in measles IgG antibdy. Specimen cllectin/submissin prcedure: Cllect at least 5 ml f whle bld in red-tp r ther tube withut anticagulant. Separate serum frm bld by centrifugatin and pur int PLASTIC serum tube, stre at 2-8 C, r freeze serum if it cannt be shipped and received in MDHHS lab within 3 days. D nt freeze whle bld. Timing f specimen cllectin Fr IgM testing: cllect ne serum between the 3rd and 30th day after nset f rash. NOTE: Measles IgM tests that are negative and were cllected less than 72 hurs after the rash nset shuld be repeated using sera cllected 72 r mre hurs after rash nset. Fr paired IgG testing; nte that IgG testing requires 2 serum specimens, acute phase and cnvalescent phase: Acute-phase specimen - cllect as sn after rash nset as pssible; Cnvalescent-phase specimen - cllect days (n earlier than 10 days) after acute-phase specimen. Test will be dne when bth specimens are received (specimens can be sent individually r acute can be held at 2-8C and sent t lab with cnvalescent specimen). If the specimens are sent t MDHHS lab separately, be sure t indicated n the Lab Request frm that this is an acute serum and that the cnvalescent specimen will fllw in apprximately days. Label tube(s) with patient name, date f birth, and date f specimen cllectin. Cmplete MDHHS Virlgy Test Requisitins Frm DCH-0583; cmplete all infrmatin in the Patient Infrmatin and Specimen Infrmatin sectins. Request measles IgM and rubella IgM in the Test Requested area NOTE: testing fr rubella is encuraged fr all suspected measles cases (likewise, testing fr measles is encuraged fr all suspected rubella cases). Be sure MDHHS Immunizatin Divisin has been ntified f the case investigatin. Ship specimens n a cld pack by vernight delivery if pssible. Mail specimens t: Michigan Department Health & Human Services Bureau f Labratries 3350 N. Martin Luther King Blvd. Building 44, Rm 155 Lansing, MI MEASLES VIROLOGY/MOLECULAR EPIDEMIOLOGY TESTING Cllect a respiratry specimen fr PCR/viral islatin in additin t the serum described abve). Page 5 f 8

6 Use a synthetic swab (nt cttn). Purpse: Virus islates and viral RNA detectin/sequencing can cnfirm a measles case, and are als imprtant fr mlecular epidemilgic surveillance, specifically t help determine the gegraphic rigin f the virus, the viral strains circulating in the U.S., and whether these strains have becme endemic in the U.S. Nte: Specimens fr measles virlgy shuld be rutinely cllected alng with serum when investigating ptential measles cases. D nt delay cllectin f viral specimens until serlgic cnfirmatin is btained, since the success f virus islatin is greatest fr specimens cllected within 7 days f rash nset. D nt cllect viral specimens if mre than 10 days have elapsed since rash nset. Specimens: Respiratry specimen - thrat swabs (rpharyngeal) r naspharyngeal (NP) swabs are the preferred samples fr virus islatin r detectin f measles RNA by RT PCR Urine - Urine samples may als cntain virus and when feasible t d s, cllectin f bth thrat swab and urine can increase the likelihd f detecting the virus MDHHS lab kit: 45 Specimen cntainer(s) Thrat swabs and ther respiratry specimens: Viral Transprt Media test tube Urine: 50 ml centrifuge tube r ther sterile cntainer Specimen cllectin/submissin prcedure: Label all specimen cntainers used with patient name, date f birth, and date f specimen cllectin. Respiratry specimens: thrat swab (preferred), naspharyngeal swab, nasal swab, r nasal wash Cllect as sn as pssible after nset f rash (n later than 10 days after rash nset). Thrat swabs (and/r nasal r NP swab): Use sterile Dacrn (r ther synthetic) swab t swab back f thrat r the naspharynx; if cllecting mre than ne specimen use separate Dacrn/synthetic swabs. Try t cllect epithelial cells. Place swab(s) in a tube cntaining 2-3 ml f viral transprt medium; submerge swab in transprt medium and express the swab against the inside wall f the specimen cntainer. Swab may be left in tube but make sure tube cap is securely screwed n; swab shaft may need t be cut dwn in rder t fit if swab is t be left in tube. Nasal wash: use syringe with small plastic tube and 3-5 ml f Viral Transprt Medium (VTM). Tilt head back, instill VTM in ne nstril, hlding ther nstril clsed; aspirate VTM fluid and specimen material quickly and gently. Rinse the tube with apprximately 2ml f VTM t btain any residual specimen. Keep specimens at 4C (refrigerated). Ship specimens n cld pack by vernight delivery if pssible. If immediate cld shipment (within 48 hurs) cannt be arranged r is nt cnvenient: Nasal wash specimens can be centrifuged at 500 g (apprximately 1500 rpm) fr 5 minutes, preferably at 4 C, and the pellet re-suspended in 1 ml f cell culture medium. If Page 6 f 8

7 pssible, the supernatant can be saved in a separate tube. The samples shuld be frzen and shipped at -70 C (dry ice). If centrifugatin is nt available, the whle specimen can be frzen (preferably at -70C) and shipped n dry ice. Nse and thrat swabs can be remved frm the transprt medium after allwing sme time fr elutin f virus. The specimen can then be frzen at -70C and shipped n dry ice. Urine specimens: Cllect within the first week after rash nset. Cllect ml r urine in a clean urine specimen cntainer (50 ml centrifuge tubes wrk well); first mrning vid is preferable, cllect urine clean catch mid-stream. If centrifugatin is available: Centrifuge at 500xg (apprximately 1500 rpm) fr 5 t 10 minutes t pellet the sediment. The supernatant shuld be discarded; resuspend the sediment in 2-3 ml f viral transprt medium r any cell culture medium. Ship frzen at -70C n dry ice. If dry ice is nt available, stre at 4C and ship n cld pack within 48 hurs. If centrifugatin is nt available, d nt freeze the urine sample. The entire urine specimen shuld be stred at 4C and shipped t the lab n cld pack. Cmplete a MDHHS Virlgy Test Requisitin Frm DCH-0583 fr each specimen. Indicate measles virus by culture/pcr in the ther sectin f the Test Requested area. Mail specimens n a cld pack t: Michigan Department Health & Human Services Bureau f Labratries 3350 N. Martin Luther King Blvd. Building 44, Rm 155 Lansing, MI Page 7 f 8

8 Measles timeline diagram Expsure Rash nset Prdrme 2-4d (1-7d) Key: Numbers in parentheses, e.g., (12-25d), are uter ranges. Signs r symptms Incubatin Infectiusness Lab specimens Prphylaxis Disease cntrl Incubatin ~14d (7-18d) Diseased Rash lasts at least 5-6d Recvered Infectius 1d befre prdrme (~4d befre rash) t 4d after rash nset Serum fr IgM 3-30d after rash nset Acute serum fr IgG ASAP after nset 10-30d Cnvalescent serum fr IgG Immunize; may prevent disease if given 3d after expsure. Give IG ; may prtect if <6d since expsure. Thrat swab (alternate: nasal wash r nse swab) and urine fr culture/pcr 7d* after rash Exclude susceptibles until 21d after rash nset in the final case. Susceptibles may be readmitted nce they are vaccinated with at least 1 dse f MMR. Exclude case thru 4 th day after rash nset. * Fr best results with viral culture, cllect specimens 3d after rash nset. D nt cllect such specimens >10d after rash nset. Give IG nly if the persn is immuncmprmised, r MMR is cntraindicated, r if >72h t <6d have passed since expsure. Surces: APHA Cntrl f Cmmunicable Diseases Manual, AAP Red Bk, CDC Pink Bk, CDC VPD surveillance manual Page 8 f 8