Saturday, April 9, 2011

Vaccine leh immunity

           Vaccine tih hi kan tawng tualleng pakhat chu a ni ve tep tawhin ka hria. Natna khirh deuh leh hrileng a awm chang apianga kan hmuiphun nena inrem ve ziah thin chu "Vaccine" tih thumal hi a ni awm e. He thil hi medical lam hian an inti tatu deuh thinin ka hria a, mahse a hria te'n an ziak tha duh miau si lova, kei hian ka han ziak leh poh a ni ang chu. Medical science background nei ka nih loh vangin kei chuan microbiology leh biotechnology lam point of view atangin ka rawn ziak ve thawr anih hi.

Vaccine chu enge?

           Vaccine hi chu kan hriat theuh angin natna hrik laka kan taksa a lo him theihna tura kan taksa chhunga natna hrik thi tawh (heat killed pathogen) emaw, natna hrik sawisak chauh tawh (weakened pathogens) emaw, an taksa peng emaw an product te emaw thunluh hi, heta an thil thunluh hi Vaccine chu a ni. Helam pang hi chu mi tam zawk hriat hnua ni bawk a, a aia pawimawh sawi ang.

Immune system

           Vaccine sawi lai laia immune system han sawi daih te chu, pawh a tih theih tho na a, a inzawm mauh mai si a, sawi tel a ngai tlats. Kan immune system ah hian Cells chi hnih B cells leh T cells te an awm a. Heng Cells chi hnih tang kawp te hian natna hrik thisen leh cells a lo lut tlang te chu an beihrawn thin a, an tichhia in an tihlum thin. B cells ho hian direct in natna hrik an bei ve lova, an aiah natna hrik bei turin antibodies an siam chhuak chiam thin. Heng antibodies te hian an milpui natna hrik chiah chiah an bei thei thin.

            Mahni taksa ami nilo, pawnlam thil reng reng, natna min thlen thei emaw thlen thei lo pawh nise, foreign bodies tawh phawt chu taksa hian a ngaithei miah lova, taksa hian a bei nghal chat thin. Hetiang foreign bodies ho zawng zawng hi antigens an ti. Antigens te hi B-cells leh T- cells te hian rang takin an bei thin a ni. An inbeihna reaction pawh hi a nasa in a sang em em a, nasatakin taksa pawhin a tawrh chang a awm thin. Antibodies chikhatin an beiha theih chu antibodies dangin an bei ve thei lo.

            T-cells ho hian direct in antigens an bei thin a, B-cells erawh chuan antibodies tam tak a siam chhuak a, chumi hmang chuan a bei thin ve thung. B-cells leh T-cells te hi an pawimawh em em a, a chi hrang hrang te'n kim taka hna an thawh theuh chauhvin natna lakah kan fihlim thei thin a lo ni.

            Entirna pakhat lo sawi ta ila: T-cells te hi chi hrang hrang an awm a (killer T-cells, suppressor T-cells leh helper T-cells), chung zinga a khawi emaw ber pawh kim lo ta se, taksa tan a hlauhawmin natna a do chak thei lo reng reng thin. AIDS thlentu natna hrik HIV hian hleper T-cells a bei thin a, taksa ah helper T-cells a lo tlem tial tial thin. a Chumi avang chuan taksa in a full in natna a do zo lo tial tial thin. (Helper T-cells te hian T-cells nasa taka in thlah pung turin a tanpui a, tin, B-cells in antibodies a siam chhuah dawnah nasa takin a pui thin bawk). Immune system-a a peng pakhat te pawhin hna a thawk tha lo anih chuan taksa tan a pawi em em thin.

            B-cells ve thung chuan, taksa ah antigens an lut a ni tih signal a dawn veleh plasma cells tam tak a siam chhuak a, plasma cell pakhat hian antibodies tam tak a siam chhuak thin. Second khat chhungin antibodies molecules 2000 vel a siam thei. Taksa in antibody a siam chhuah hian, antigen bei thei tur, a milpui chiah chiah a siam thin a. Antigen hrang hrang tan antibody chi hrang hrang a siam chhuak anih chu. Taksa ah antibody awm teuh pawh nise, an milpui chiah chiah lo chu an bei thei miah lo.


Memory T-cells and antibodies

          Taksa in antigens lo lut bei tura T-cells leh B-cells tam tak a siam chhuah te chu rei lo te ah an thi boral ve leh mai a. Chung zingah chuan a damrei pawl an awm a. Chung a damrei pawl ho chuan sipaiin an ram hneh an luah ang maiin taksa ah duty in rei tak an dam thin. heng ho hi memory cells an ti a. Natna ngai chiah taksa ah a rawn lut leh vaih anih chuan rang takin an lo man chhuak chaih chaih thin. Memory cells te hi thla khat an dam chuan, natna ngai chiah lakah khan thlakhat chhung taksa a him dawn tihna a ni a, kum khat an dam chuan kum khat chhung a him dawn tihna a ni. He memory cells taksa ina asiam dan atang hian vaccine kan tih hi a lo chhuak ta a ni.

            Vaccine principle ah chuan, natna in taksa a run a, taksain natna a lo hneh anih chuan taksa ah memory cells te an insiam ang a, chung memory cells te chuan chu natna lakah chuan taksa an veng tlat tawh dawn a ni. Natna hrikte hi taksa ah natna siam thei lo turin sawisak emaw, tihhlum emaw phawt hnuah taksa ah dahlut ta ila. Taksa chhunga an luh veleh taksain antigens angin a lo hmu ang a, T-cells tam tak leh antibodies rualin an beihrawn nghal ang. Chu natna hrik thi tawh chuan taksa ah natna thlen lo pawh nise an bei tho ang a, chumi hnuah memory cells an siam chhuak teuh ang. Chung memory cells te chuan taksa an venghim tlat dawn a ni.

            Natna hrik tihhlum tawh emaw, natna thlen theilo tura sawisak emaw, taksa chhunga an kah luh hi vaccine chu a ni ta a ni. Vaccine taksa chhunga a luh hnuah taksa venghimtu tur sipai duty memory cells te, taksain a dah teuh ang a, chung memory cells te chu kum 10 an dam anih chuan kum 10 chhung chu natna lakah chuan taksa a himdam thei dawn tihna a lo nih chu.


Vaccine hmuh chhuah dan

           Hei hi introduction ah dah awm tak a ni a, mahse, mak takin a hnudawlah ka han dah daih anih hi. Kum zabi 18na vel ah khan England ah small pox hri a leng nasa hle mai a. Mi tam takin an thih phah a. Chutih lai chuan bawng vulhtu thenkhatin small pox an vei ve miah lo ani tih chu Edward Jenner chuan a hmu chhuak ta a. Bawngvulhtu te hian small pox aia hlauhawm loh zawk, cow pox an vei thin a, chutianga cow pox vei tawh, dam leh tawh o chuan small pox an vei ve miah lo ani tih a hre ta a. Chuti anih chuan cow pox natna hrik chu taksa ah kah luh nita se, chu chuan small pox lakah taksa a ven theih a ring ta tlat mai a ni. Tunge natna khirhkhan tak lak atanga him inbeisei vanga natna hrik dang taksaa dah luh duh ta ang le? A risk a sang khawp mai. Jenner-a huanpu fapa mipa naupang kum riat mi James Phillip lakah experiment a ti thei ta hlauh mai. Hemi kum hi kum 1796 a ni a, bawnghnute sem thin Sarah Nelmes-i cow pox vanga taksa bawl pan chhunga thil tui la chhuakin chu naupang banah ah chuan Edward Jenner chuan a chiu luh sak ta a. Chu naupang chuan a banah cow pox natna bawl leh pan a rawn lang chhuak a; a hnuah naupang taksa ah chuan small pox natna hrik a han chiu lut a, mahse thihna thlen theitu natna rapthlak tak small pox erawh a vei ve ta reng reng lo. Naupang taksaa cow pox hrik dahluh anih avangin naupang chuan small pox lakah resistance a lo nei ta anih chu. Hei hi vaccine lo chhuah tanna chu a ni ta.


Photo: Edward Jenner

           Edward Jenner-a thil hmuhchhuah avang hian mi sang tam takin an nunna an humhim theih phah ta a, chuvang chuan Edward jenner pawh, tun thlengin khawvelin a hming a theinghilh thei tawh lova, "Father of Immunology" tia hriat reng a ni kumkhua tawh dawn a ni.


Vaccine chi hrang hrang te:

            Kan sawi ta sa sa, sawi zawm zel ang aw. Natna hrik tihhlum hnu emaw tih chauh hnu emaw, taksaa kah luh vaccine chauh ni lovin, vaccine chi hrang hrang kan nei ta. Vaccine te hi virus atanga siam anih chuan viral vaccine an ti a, bacteria atanga siam a nih chuan bacterial vaccine an ti ve thung.

1. First generation vaccine:

            Natna hrik taksa pumpui vaccine atan hman a nih hian first generation vaccine an ti. Chi thum lai a awm a. Heat killed or killed -Virus emaw bacteria emaw kha an tihhlum hmasa phawt a, vaccine atan an hmang thin. Inactivated - Virus emaw bacteria emaw kha inthlahpung thei miah lo turin an khawih zal hmasa thin. Attenuated - Virus emaw bacteria emaw, a nung lai ngei vaccine atan hman a ni. Hetiang atana an hman ho hi chu an inthlahpung chak lo em em a, taksaah natna an thlen meuh lo. Attenuated hi a thawk chak ber a, mahse risk erawh a sang deuh chuan ka hria.

            Bacteria thenkhat hian taksa ah tur a siam chhuak thin a, chu tur chu ka damloh pui thin a ni. He tur hi toxins an ti. Toxins te chakna hi biomolecules, proteins an ni tlangpui a, formaldehyde nen an sawisak hnuah tur toxin chuan a tur nihna a hloh ta a, toxin ni tawh lovin toxoids a lo ni a ni. Toxoids hi vaccine ang thovin taksaah, natna laka taksa veng turin an chiu lut thin. eg. tetanus toxoid hi tetanus tur, tetanospasmin atanga siam a ni. Hetiang vaccine hi toxoid vaccine an ti.

2. Second generation vaccine:

            He vaccine hi sub-unit vaccine an ti bawk. Bacteria taksa peng engpawh (capsule, pili, etc) hi vaccine angah a hman theih. Entirna pakhat lo sawi ta i la; bacteria te hian an bei ngheh nan pili (hmul ang tak) an mamawh a; pili chu an extract a, chu chu vaccine angin an hmang ta a. Taksaa a luh veleh taksa ah amah do turin antipili antibodies tam tak a insiam ta a. Chu antibodies chuan cell a bacteria bet thei tur a veng tlat thei a, tichuan bacteria in cell a bei thei miah lo tihna anih chu.

            Tin bacteria chhah taka tuamtu kawrah hian polysaccharides chi hrang hrang an awm a, chu chu an extract a, vaccine atan an hmang bawk. Hetiang hi pneumonia natna thlentu Streptococcus pneumoniae tan vaccine hlawhtling tak an siam bawk.

3. Third generation vaccine

            Chi hnih a awm a: recombinant DNA vaccine leh recombinant protein vaccine. Thil inzawm reng a ni a. Recombinant DNA a awm chuan recombinant protein siam chu thil harsa a ni lo, a chhan chu DNA atangin protein a insiam chhuak thei miau si a. (Recombinant DNA technology hi genetic engineering a ni a, ka peih chuan ka la ziak ang; mahse mizotawnga ziak chu a huphurhawm khawp ang le).

            Hetiang vacine hi chu a technology a sang deuh a, recombinant DNA technology hmangin an siam chhuak thin. Viral DNA emaw Bacterial DNA emaw an duhlai ber an la chhuak phawt a, chu an DNA extract sa chu plasmid ah an clone pung chiam a. (Tin, DNA hi  PCR hmangin an ti pung chiam thei bawk). Heng DNA te hi an extract leh a, chu chu vaccine atan an hmang ta thin a ni. DNA hian protein a siam chhuak thin a. Taksaa kah luh a nih veleh taksa ah protein a insiam a, chu protein chu rang takin immune system in a lo man chhuak nghal a, T-cells chi hrang hrang leh antibodies a rawn siam chhuak ta teuh va. Chung zinga thenkhat chu memory cells ah insiamin rei tak taksa an venghim thei a ni. Hetiang hi DNA vaccine an ti. Recombinant DNA Vaccine hi risk a la sang deuh na a, a hlawhtling tak tak anih chuan tha ber leh awlsam ber tura ngaih a ni. Hlawhtling takin bird flu vaccine an siam chhuak.

             DNA te hi plasmid ah dah luh anih hnuin, plasmid chu bacteria ah an dahlut a, an culture a, an inthlah pung chiam a, culture chamber atangin protein an siam chhuahte an la chhuak a. Chu protein chu vaccine atan an hmang bawk. Hepatitis B vaccine chhuak thar ho kha a tlangpuiin hi recombinant viral proteins vaccine an ni.

Passive leh active immunity:

            Kan taksaah vaccine kan kah luh avanga taksaa antibodies a rawn insiam a, natna hrik ngai chiah lo lut leh tur laka min ven hian, chu immunity chu active immunity an ti. Vaccine hi siam chawp a nih vangin artificial active immunity an ti thin bawk. Kan taksaa natna hrik lut tawh vanga kan taksaa natna do theitu a insiam hian active immunity tho a ni a, mahse thlentir chawp a nih loh vangin natural active immunity an ti.

            Kan taksa chhunga insiam ni lova, antibodies awmsa, insiam sa, kan taksa chhungah a lut a, chu chuan kan taksa ah immunity a siam chuan passive immunity an ti. Blood serum kan tih ho ah hian antibodies tam tak a awm thin a, chutiang chu artificial passive immunity an ti. Tin nausen hian an taksa ah natna do theihna an nei lo va, nu taksa atangin antibodies siamsa an dawng thin a. Chu chu natural passive immunity an ti bawk. Tin, kan hriat belh ve mai mai atan, antibodies hi hybridoma technology hmangin laboratory ah an siam chhuak thin bawk.Heta antibodies an siam chhuah hi monoclonal antibodies an ti.

Nausen leh natural immunity

            Nausen te hi an pianhlim hian an taksa a la no em em a, natna do theihna (immunity) an taksa ah a la insiam ve thei miah lo. Mahse natna do theihna an nei ve tho si. Eng tiangin nge ni le? Nu in nau a pai laiin ama taksaa antibodieas a siam te chu laihrui kaltlangin chhul chhunga naute a pe chhawng thin a. Heng antibodies siamsa te hmang hian naute chuan natna do theihna immunity a lo nei ve thei thin. Tin, nu hnute tui chhuak hmasa, rawng eng lam deuh, hnang ban lampang lek lek hi colostrum an ti a, hetah hian taksa siamtu protein leh natna do theitu antibodies a tam em em thin. Hei vang hian hnute tu chhuak hmasa colostrum hi nausenin an hne ngei ngei tur a ni. Nu taksaa antibodies siamsa naute ina a dawn hmang hian naute chuan natna do theihna a lo nei ve ta thin a ni. Heng antibodies te hi a tlangpuiin thla thum atanga thla ruk a dam a, tin sentut natna hrik do theitu antibodies te hi nausen taka ah thla 12 atanga thla 15 thleng an dam thei bawk. Naupai laia vaccine lak pawimawh zia, tihian  ka hre thei mai awm e.
       

             Khing vaccine chi hrang hrang ka rawn tarlan ah te khian, a chung ber ami khi a siam a awlsam ber a,  hman tlanglawn ber pawh a ni a, mahse natna hrik tak taka kha vaccine atana hman anih avangi risk  tlem a awm tel a ni.  Chuvangin a aia tha siam chhuah tumin theihtawp chhuah mek reng a ni a, second generation vaccine leh third generation vacine vek hi hman theih hun pawh a la thleng maithei hial a ni. Ka thuziak te hi, a ziaktu ang deuh hian a up-to-date vak tawh lo mai thei a, a chhiar dan tawk pawh thiam a ngai viau ang. Biotechnology hi hmalam pana kal reng a nih vangin thil thar a chhuak reng a; a enga pawh chu ni ta se, a pawimawh lai bera chu engtin nge vaccine hi an siam a, vaccine chuan engtin nge hna a thawh thin tih lai tak hi a ni awm e. A chhiar zau peih tan chuan lehkhabu hrang hrang leh internet lamah chhiar belh tur a tam khawp mai.

(Medical lam mi ka ni lova, ka hre ril lo hle. Science atangin ka rawn ziak anih hi)

22 comments:

  1. Hei zet chuh, a scientific lutuk tlat mai ka tan chuan... Amaherawhchu a chhawr tangkai thiamte tan chuan a va pawimawh dawn em.. Edward Jenner erawh kan school kal lai atang tawh khan ka ngaisang tawp theilo

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  2. A va hlu ve le, a informative lutuk tlat; Pawl 10 thleng Science ka zir tih loh kha chu ka chhiar ta mang mang lo. Biology erawh ka tui ve hle thin a, Physics hian ka tuina a paih vek a.

    Englekhawle, Thianpa, i thu post hi ka'n save ang a, kan nu ka'n chhiartir ve bawk ang e; ani hi hetiang lam medical Science lo zir sil ve nial tawh anih avang hian a tui ve em em thin.

    I post hi a ngaihnawm lam aiin a hlu.

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  3. Ka blog min hlutsaka min chhioar saktu te hi ka tan chuan an va hlu thin tak em. Mi tih loh dan angin a mal malin ka'n response leh teh ang.

    @CyberThug:
    Ka blog tlawm takah hian ka lo lawm lut a che. "I rah chin apiang i ram a ni zel ang," tih ang deuh khan, ka blog i rawn rap ta sa sa, i ram chhung angah ngai la, a neitu chan chang takin i duh duh i sawi thei ang.

    Science lam pang hi mizotawnga ziah a harsa duh phian mai. Theihtawp chhuaha beiha ziak a ngai ve tlat mai. Ka ziah dawn tak tak hi chuan ka ip ru a, ka huphurh thei asin aw.

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  4. @Rpa Pachuau:
    Ka thuziak min fak sak a, ka lawm e. Science lam ve hi zawng, a ngaihnawm tak tak thei lo anih hi. Mizotawng ziak lah hi a harsa zek lehnghal a.

    Vaccine hi kan hre lar hlur a, enge a nihna diktak erawh hrelo kan tam thin em a, tihian ka han ziak ve tawp anih hi. Kan Dr Khumchiktheia lah hian engmah a ziak tha ve duh tak tak mang si lo. MIn chhiar sak mai bakah comment tha tak min hnutchhiah sak vangin ka lawm e.

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  5. A bengvarthlak leh pek hle mai! Science lama tui miah lo tan pawha thil tangkai tak a nih hi. Comment dan pawh ka thiam vak lo! :)

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  6. @TS-a:
    Comment dan chu hei i thiam reng hi maw le.... Thiam lo chung chunga comment te hlei hlei hi ka tan a hlu a nia. Kan naupan lai khan sikulah vaccine hmangin kan injection thin a, ka huphurh thei thin a nia aw.

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  7. Avan ngaihnawm cher cher vele. Thu bengvar thlak tak a ni.

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  8. Ka hriatna a pung leh ta. Kan naupan laia vaccine la tura sikul kawta kan intlar pat thin te pawh min hriat chhuah tir a lawm mawle. Hma amite an han chiu a, na ti awm takin an han awma kan hun a thlen dawn kha chuan kan va han huphurh thei tak e aw

    Vaccine hian dam chhungin min veng tawh turah ka lo ngai ngawta,i han sawi danah khi chuan memory cell te dam chhung chauh a veng dawn tihna a lo ni maw, ka naupan laia TB leh tetanus vaccine ka lak pawh khan min veng tawh lo mai ang a,memory cell te kha an lo thi vek tawh lawng maw

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  9. @H.V.:
    Ka lawm e. Nang nge nge, i hun chep tak karah pawh mi i rawn tlawh leh hram thin a.

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  10. @triplestar:
    Vaccine hi a lo inang lo thei khawp mai. A then chuan min veng rei a, a then erawh chuan min veng rei lem lo. Tetanus vaccine hian min veng rei vak lo vin ka va hre deuh e. Memory cells ho kha immunity siamtu chu an ni deuh mai a, an dam rei leh rei lohah a innghat ang chu.

    Aizawl lo zin hun chuan in artui hip turin a hranpa ngatin rawn tlawh che ila a that dawn hi, te ka lo tia.

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  11. Ka save a, kan science teacher ka chhiartir ve a. Tha a ti lutuk tlat... I article dang pawh min chah lawm lawm mai

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  12. @CyberThug:
    Keia thuziak mai mai hian tu lunglai a dum zawh pawh ka lo ring hlei nem. Nang nge nge, mi i hlutsak thiam thin a, ka lawm e.

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  13. E khai! Hotupa, i blog chu hmuh a nuam ka hle mai. Mit a hîp nghal zar mai nia. A tha lutuk ringawt.

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  14. TS, blog var pup mai ka nei a, chhiar a hahthlakin mit a kham duh em em a, chuvangin nimin khan ka ninhleiin a colour vel ka han thlak kual chhin a, tihian en a lo hahdamthlak zawk daih a ni tih ka hre ta a, ka thlak ta anih hi.

    Mifing chuan tawngkamtha an ui lova, midangte rilru hlimna tur anih chuan fak hun an hre thei khawp mai an ti. Min fak sak a, ka lawm e.

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  15. cari, i duh phawt chuan artui hip tur hrim hrim pawhin min rawn tlawh teh khai, i haw leh hunah in nu a lawm dawn em a sin, i thianpa triple-a kha va tlawh leh ta che a ti deuh reng mai angah eh.. :-D

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  16. Triplestar, ha ha ha..... min va tinui nasa ve le. Ngawi tak rawh, ka lo la zin dawn alawm. I artui tharlam ngat kha ka han hip mah ang a e, a thawk chak dawn em asin.

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  17. Exam naah rawn chhuak tase ka Fail chiang mai mai ang chu :D Edward Jenner chu ka hre ve thin. Keini ang Science leh Medical lama bo lutuk, Nu berin hnute tui tamna damdawi a dahthat lo thawk khat ve hmiah thin tan chuan hriatthiam a har khawp mai. Tu emaw tihdan takah, Sap tawng a tam em mai, a ril viau a niang :D

    Tak tak a, keini ang mai mai tan pawh hian hriat belh zel tluka hlu a awm lova, i zarah kan hriat loh tha tha kan hre ve ta teuh mai. I post tha khawp mai a, a tlangpuiin i thil post te hi chhiar liam mai lova, a zira zir tlak vek a ni e.

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  18. @Dawldanga:
    Thianpa chuh, i comment ka chhiar a, mahniin ka nui ur kur mai. Min fak nasa leh lutuk a, ti'ang te chuan tak tak emaw ka ti leh mai anga sin le. "Saptawng a tam em mai, a ril viau ang" i tih lai mawlh mai hi.... Ha ha ha.

    Thian duhtak te u, ka blog tlawm taka in lo lenluh thin avang te, ka thuziak fahrah te te min chhiar sak hram thin avang te hian lawmthu sawi lo thei lo ka ni a. In hun chep tak karah pawh comment thlum tak tak leh hlu tak tak min hnutchhiah sak thin avang hian lawmthu ka han sawi nawn leh e.

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  19. A beng var thlak hle mai,vaccine lo chhuah tan dan te hi ka tan chuan thil thar ani. i ziak tha khawp mai

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  20. Hmanni khan ka comment a, alo lang lo ani maw.

    Naupang vaccine pek lek pek lohvah hi an inhnialna, western ram lamaha hian a awm tan viau. MAhse, vaccination lak avanga nunna chhanhim erawh ala tam zawk ngei ang chu.

    A bengvarthlak leh mai.

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  21. @Ramenga:
    Min comment sak avangin ka lawm e. Vaccine chungchang hi ziak tur a tam a, ziak kual thui a ngai thei lutuk a, tihian phuai luai takin ka han ziak ve thawr anih hi.

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  22. @sekibuhchhuak:
    Vaccine hi chu natna hrik emaw an product kaihhnawih emaw ngang hi a nia, sawisel nasat pawh tawk ta viau mahse a awm ve tho mai. Mahse, mihring nunna hi a chhanhim nasa tawh em mai a, a tha a niang, tun thleng hian vaccine la duh lo aiin la duh an tam zawk zel rih e. HIV vaccine te pawh hmuhchhuah tumin tan an lak nasat em hi maw.

    Keini tropics rama cheng tan ngat phei hi chuan vaccine hi a lo pawimawh khawp mai.

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