presentation mv

8/14/2019 Presentation MV

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SPECIMEN COLLECTIONSPECIMEN COLLECTION

FORFOR

MEASLES VIRUS ISOLATIONMEASLES VIRUS ISOLATION

Eshetu LemmaEshetu Lemma

BSc (MLT), BA (Econ)BSc (MLT), BA (Econ)Measles Lab Data ManagerMeasles Lab Data Manager


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INTRODUCTIONINTRODUCTION

Virus isolate are extremely important forVirus isolate are extremely important for

molecularmolecular epidemiologic surveillanceepidemiologic surveillance toto

help determine the geographic origin of thehelp determine the geographic origin of thevirus and thevirus and the viral strain circulateviral strain circulate

Isolation of measles virus is notIsolation of measles virus is not

recommended as arecommended as a routineroutine method tomethod todiagnosis measlesdiagnosis measles

Measles virus can be isolated fromMeasles virus can be isolated from

nasopharyngeal aspirate or swab, throatnasopharyngeal aspirate or swab, throat

swab, blood, and urineswab, blood, and urine

Clinical specimen for viral isolation shouldClinical specimen for viral isolation should

be collected at thebe collected at the same timesame time as samplesas samples

taken fortaken for serologicserologic testingtesting


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MVMV is more likely to be isolated when the specimens areis more likely to be isolated when the specimens are

collectedcollected within 4 dayswithin 4 days of rash onsetof rash onset

Collection of specimens for virus isolationCollection of specimens for virus isolation should not beshould not be

delayeddelayed untiluntil serologicserologic confirmation is obtainedconfirmation is obtained

Throat and nasopharyngeal specimens can be collectedThroat and nasopharyngeal specimens can be collected

in order of in order ofincreasingincreasing virus yieldvirus yield

-by aspiration-by aspiration

-by lavage-by lavage-by swabbing of the mucous membranes-by swabbing of the mucous membranes

The sensitivity ofThe sensitivity ofnasal swabsnasal swabs is comparable to that ofis comparable to that of

nasopharyngeal aspiratesnasopharyngeal aspirates for detection measles virusfor detection measles virus


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Types of SpecimensTy

pes of Specimens

- nasopharyngeal aspirate- nasopharyngeal aspirate

-- nasopharyngeal swabnasopharyngeal swab- nasal wash- nasal wash

-- throat swabthroat swab

- urine- urineMaterials RequiresMaterials Requ

ires

- gloves and mask- gloves and mask

- sterile dry swab- sterile dry swab

-- tongue depressortongue depressor


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Cont...Cont...

-- suction devicessuction devices

(syringe, vacuum pump or wall suction)(syringe, vacuum pump or wall suction)

- specimen trap- specimen trap-- cathetercatheter

-sterile saline or culture media-sterile saline or culture media

-- Viral transport mediumViral transport medium (VTM):(VTM):

sterilesterile, usually consisting of Hanks balanced salt, usually consisting of Hanks balanced salt

solution andsolution and antibioticsantibioticsto reduce bacterialto reduce bacterial

contamination growthcontamination growth

- ice bag- ice bag- investigation forminvestigation form

- labeling material- labeling material


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Nasopharyngeal Swab CollectionNasop

haryngeal Swab Collection

11. When you collect the specimens, wear gloves and. When you collect the specimens, wear gloves and

aa maskmask

22. If the patient has. If the patient has a lot of mucus in the nosea lot of mucus in the nose, this, this

cancan interfere with the collection of cells. Eitherinterfere with the collection of cells. Either

ask theask the patients to use apatients to use a tissuetissue to gentlyto gently clean outclean out

visible nasalvisible nasal mucusmucus or clean the nostril yourselfor clean the nostril yourself

3.3. Prior to insertion,Prior to insertion, measuremeasure the distance from thethe distance from the

cornercorner of the nose to the front of ear and insertof the nose to the front of ear and insert

thethe shaft onlyshaft only half this lengthhalf this length


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Cont...Cont...

4.4. Seat the patient comfortably. TileSeat the patient comfortably. Tile

the patient'sthe patient's

head back slightlyhead back slightly

toto

straighten the passage from the frontstraighten the passage from the front

of theof the nose to the nasopharynxnose to the nasopharynx toto

make insertion of the swab easiermake insertion of the swab easier

5.5. Using a swab with a flexible shaftUsing a swab with a flexible shaft

gentlygently insert the swab along medialinsert the swab along medial

part of the septum,part of the septum, along the base ofalong the base of

the nosethe nose, until it reaches the, until it reaches the

posterior naresposterior nares


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Cont...Cont...

6.6. ThenThen gentle rotationgentle rotation of the swab mayof the swab maybebe helpfulhelpful

7.7. Rotate the swab several times toRotate the swab several times todislodgedislodge thethe columnar epithelialcolumnar epithelialcellscells

8.8. Withdraw the swab and place it inWithdraw the swab and place it in VTMVTM

or the collection tube with Saline oror the collection tube with Saline orcultureculture mediamedia ((squeeze bottom of thesqueeze bottom of thetube to release mediatube to release media))

9.9. Snap the end of the swab to make it fitSnap the end of the swab to make it fit

more easilymore easily10.10. Seal the tube.Seal the tube. Label the specimenLabel the specimenwithwith patient's name, date ofpatient's name, date ofspecimen collection and typespecimen collection and type ofofspecimenspecimen


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Cont...Cont...

11.11. Specimens should be shippedSpecimens should be shipped

onon

wet ice atwet ice at

4-84-800

cc

and shouldand should

arrive at the nationalarrive at the national

measles laboratory within 48 hoursmeasles laboratory within 48 hours

Fig.1 Nasopharyngeal SwabFig.1 Nasopharyngeal Swab

CollectionCollection


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Throat Swab Collection MethodThroat Swab Collection Method

1.1. Do not obtain throat samples ifDo not obtain throat samples ifepiglottisepiglottisis inflamed, as sampling may cause seriousis inflamed, as sampling may cause seriousrespiratory obstructionrespiratory obstruction

2.2. Depress tongueDepress tongue gently withgently with tonguetonguedepressordepressor

3.3. Extend sterile swab between the tonsillarExtend sterile swab between the tonsillarpillars and behind the uvula. (pillars and behind the uvula. (AvoidAvoid touchingtouching

thethe cheeks, tongue, uvula or lipscheeks, tongue, uvula or lips))

4.4. Sweep the swabSweep the swab back and forthback and forth across theacross theposterior pharynx, tonsillar area and anyposterior pharynx, tonsillar area and any

inflamed or ulcerated areas to obtain sampleinflamed or ulcerated areas to obtain sample


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Cont...Cont...

5.5. Withdraw the swab andWithdraw the swab and place it in VTMplace it in VTM or theor the

collection tube withcollection tube with SalineSaline oror culture mediaculture media

6.6. Snap the end of the swab to make it fit moreSnap the end of the swab to make it fit moreeasilyeasily

7.7. Seal the tube. Label the specimen withSeal the tube. Label the specimen with

patient'spatient's name, date of specimen collectionname, date of specimen collectionand type ofand type of specimenspecimen

VTMVTM

SwabSwab

SpongeSponge

containingcontaining

VTMVTM


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Nasopharyngeal AspirationNasopharyngeal Aspiration

1.1. Prepare aPrepare a suction devicessuction devices (syringe, vacuum(syringe, vacuumpump, or wall suction), specimen trap and catheterpump, or wall suction), specimen trap and catheter

2.2. Insert catheter nasally intoInsert catheter nasally into posteriorposteriornasopharynxnasopharynx

3.3. Apply suction as catheter is slowly withdrawnApply suction as catheter is slowly withdrawn

4.4. If sample has been aspirated into a syringe sealIf sample has been aspirated into a syringe seal

the end of the aspiration tube and sendthe end of the aspiration tube and sendspecimen in syringespecimen in syringe

5.5. Place sample inPlace sample in transport mediumtransport medium into sterileinto steriletransport vialtransport vial

6.6. Ensure that the top of the vial is screwed onEnsure that the top of the vial is screwed onsecurelysecurely


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Cont...Cont...

7.7. Label with patient name, dateLabel with patient name, date

of birth,of birth,

sample type and datesample type and date

of collectionof collection

8.8. Then specimens should beThen specimens should be

shipped on wetshipped on wet iceice at 4-8at 4-800cc andand

should arrive at theshould arrive at the nationalnational

measles laboratory within 48 hoursmeasles laboratory within 48 hours

U i C ll i M h d


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Urine Collection MethodUrine Collection Method

1.1. First morningFirst morning voided specimens are ideal,voided specimens are ideal,butbut any urine collection is adequate.any urine collection is adequate.

2.2. CollectCollect 10-50 ml10-50 ml of urine in a urineof urine in a urinespecimenspecimen containercontainer

3.3. After collection, keep the specimen coolAfter collection, keep the specimen cool(refrigerator or wet ice)(refrigerator or wet ice)

4.4. If centrifugation is not available,If centrifugation is not available, do notdo not

freezefreeze the urine samplethe urine sample. The entire urine. The entire urinespecimenspecimen should be storedshould be stored at 4 Cat 4 C, and, andshipped to theshipped to the measles lab on coldmeasles lab on coldpacks.packs.


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Cont...Cont...

5.5. Most urine collection cups areMost urine collection cups are not leak-not leak-

proofproof. Transfer the urine to sterile plastic. Transfer the urine to sterile plasticcentrifuge tubescentrifuge tubes

6.6. AfterAfter collection, keep the specimen cool, keep the specimen cool

(refrigerator or wet ice).(refrigerator or wet ice). It is best to centrifuge theIt is best to centrifuge the

urine specimen as soon after collection as possibleurine specimen as soon after collection as possible

7.7. If facilities are available, centrifuge theIf facilities are available, centrifuge the

urine at 400 x g for 10 minutes at 4 C tourine at 400 x g for 10 minutes at 4 C to

pellet the sedimentpellet the sediment


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Cont...Cont...

8.8. Re-suspend the sediment inRe-suspend the sediment in 2 ml of VTM2 ml of VTMor any cell culture medium and shipor any cell culture medium and ship

9.9. Preferably, specimens that have beenPreferably, specimens that have been

centrifuged and re-suspended should becentrifuged and re-suspended should be

frozen at -frozen at -70 C70 C andand shipped on dry iceshipped on dry ice

10.10. If dry ice is not available, however, theyIf dry ice is not available, however, they

can be stored atcan be stored at 4 C4 C and shipped on coldand shipped on cold

packspacks

i fA ti t f NML K N t


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Activates of NML:Activates of NML: Key NotesKey Notes

Lab. is established the isolation of measles virus from clinicalsamples

29 S29 Samples were collected from 2006-08, only five were positiveamples were collected from 2006-08, only five were positiveMV, 3 isolates were sent to RRL : B3MV, 3 isolates were sent to RRL : B3

Publication , Genetic characterization & progression of B3measles genotype in Ethiopia: EMJ, V 46, No.1, 2008)

CONCLUSIONCONCLUSION


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CONCLUSIONCONCLUSION

For practical purpose,For practical purpose, Ethiopian caseEthiopian case, the best, the bestor choice of specimen for MV isolation isor choice of specimen for MV isolation isnasopharyngeal swab, nasal swab, throatnasopharyngeal swab, nasal swab, throat

swab and urineswab and urine in order of decreasing virusin order of decreasing virusyieldyield

Samples for MV isolation, should beSamples for MV isolation, should be within orwithin orless than 5 daysless than 5 days after onset of rashafter onset of rash

Variables on theVariables on the investigation forminvestigation form includingincludingname, age, date of onset, type of specimenname, age, date of onset, type of specimen,,etc should be filled properlyetc should be filled properly

If the type of specimen isIf the type of specimen is urineurine, don't, don't

centrifuge with ordinary centrifuge whichcentrifuge with ordinary centrifuge whichdoesn't holddoesn't hold -4-400cc, rather send it to national, rather send it to nationalmeasles lab. at refrigerator temp (4-8measles lab. at refrigerator temp (4-800c).c).

C tC t


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Cont...Cont...

At least 5 samples should be collected fromseparate chains of transmission

Some of samples were not good such ascontamination, inappropriate collection

Measles virus isolation will be done only foroutbreak measles case

Call to notifyCall to notify national measles lab. ofnational measles lab. ofspecimen being delivered through phonespecimen being delivered through phonenumbernumber (+251 011 277 84 80 or 277 84 77)(+251 011 277 84 80 or 277 84 77)

If immediate cold shipment can not beIf immediate cold shipment can not bearranged, call thearranged, call the national measles labnational measles lab. to. todetermine the best method to handle thedetermine the best method to handle thespecimenspecimen


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TUTU

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