Tovuti hii inatekeleza vipengele vya msingi kwa sasa na bado haiko tayari kwa matumizi ya wagonjwa.
Tovuti hii inatekeleza vipengele vya msingi kwa sasa na bado haiko tayari kwa matumizi ya wagonjwa.
Chanjo ya homa ya manjano ni chanjo hai iliyodhoofishwa inayotokana na aina ya 17D ya virusi vya homa ya manjano, iliyotengenezwa kwa mara ya kwanza mwaka 1937 na Max Theiler (Tuzo ya Nobel 1951). Chanjo hii inazalishwa kwa kupandikiza virusi katika mayai ya kuku yaliyorutubishwa, na aina kuu mbili za uzalishaji zinatumika: 17DD (inayozalishwa na Bio-Manguinhos nchini Brazili) na 17D-204 (inayozalishwa na Sanofi Pasteur na wazalishaji wengine). Homa ya manjano ni ugonjwa hatari unaosababishwa n
Chanjo ya homa ya manjano ni chanjo hai iliyodhoofishwa inayotokana na aina ya 17D ya virusi vya homa ya manjano, iliyotengenezwa kwa mara ya kwanza mwaka 1937 na Max Theiler (Tuzo ya Nobel 1951). Chanjo hii inazalishwa kwa kupandikiza virusi katika mayai ya kuku yaliyorutubishwa, na aina kuu mbili za uzalishaji zinatumika: 17DD (inayozalishwa na Bio-Manguinhos nchini Brazili) na 17D-204 (inayozalishwa na Sanofi Pasteur na wazalishaji wengine).
Homa ya manjano ni ugonjwa hatari unaosababishwa na virusi vya jenasi Flavivirus, unaoenezwa na mbu wa aina ya Aedes na Haemagogus. Ugonjwa huu unapatikana katika maeneo ya kitropiki ya Afrika na Amerika ya Kusini. Katika Afrika Mashariki, nchi kama Uganda, Kenya, na Ethiopia zimeathiriwa na milipuko mbalimbali, ikiwa ni pamoja na mlipuko mkubwa wa Uganda mwaka 2016.
Kulingana na Kanuni za Kimataifa za Afya (IHR 2005) zilizorekebishwa, chanjo ya homa ya manjano ndiyo chanjo pekee inayohitajika kisheria kwa usafiri wa kimataifa. Nchi takriban 40 zinahitaji ushahidi wa chanjo kwa wageni wanaoingia. Wizara ya Afya ya Tanzania na Kenya zimejumuisha chanjo hii katika mpango wa chanjo za dharura katika maeneo yenye hatari.
Shirika la Afya Duniani (WHO) lilipendekeza mwaka 2013 kwamba dozi moja ya chanjo inatosha kutoa kinga ya maisha yote, na mwaka 2016 marekebisho rasmi yalifanywa kuondoa hitaji la nyongeza baada ya miaka 10. Hata hivyo, baadhi ya nchi bado zinahitaji ushahidi wa nyongeza.
Chanjo ya homa ya manjano inapendekezwa kwa vikundi vifuatavyo:
Wasafiri wa kimataifa:
Watu wote wanaosafiri kwenda maeneo yenye maambukizi ya homa ya manjano katika Afrika Kusini mwa Jangwa la Sahara na Amerika ya Kusini ya kitropiki
Wasafiri wanaopitia nchi zenye hatari (nchi nyingi zinahitaji ushahidi wa chanjo hata kwa wasafiri wa kupitia)
Wasafiri wanaokwenda maeneo ya vijijini au misitu katika nchi zenye maambukizi
Wakazi wa maeneo yenye maambukizi:
Watu wanaoishi katika maeneo ya Afrika Mashariki yenye hatari ya homa ya manjano (Uganda, Kenya magharibi, Ethiopia kusini)
Wakazi wa mipakani na maeneo yenye msitu mnene
Wafanyakazi wenye hatari ya kazini:
Wafanyakazi wa maabara wanaoshughulikia virusi vya homa ya manjano au sampuli zenye maambukizi
Wahudumu wa afya katika maeneo yenye milipuko hai
Wafanyakazi wa misaada ya kibinadamu wanaofanya kazi katika maeneo yenye maambukizi
Mpango wa Chanjo za Kinga (EPI):
WHO AFRO inapendekeza chanjo kwa watoto wenye umri wa miezi 9-12 katika nchi zenye maambukizi
Tanzania na Kenya zimejumuisha chanjo ya homa ya manjano katika mpango wa EPI kwa maeneo ya hatari
Kampeni za nyongeza za chanjo zinafanywa mara kwa mara katika wilaya zenye hatari kubwa
Kulingana na WHO, takriban watu milioni 400-500 wanahitaji chanjo hii kila mwaka katika Afrika.
Kizuizi kamili (chanjo haipewi kamwe):
Mzio mkubwa wa anafylaksia kwa dozi ya awali ya chanjo ya homa ya manjano au kiungo chochote cha chanjo
Mzio mkubwa wa protini za mayai ya kuku (anafylaksia iliyothibitishwa)
Watoto chini ya miezi 6 (hatari kubwa ya ugonjwa wa neva — YEL-AND)
Upungufu mkubwa wa kinga mwilini:
Magonjwa ya thymus au historia ya kuondolewa thymus (thymectomy)
Kizuizi cha muda (ahirisha chanjo):
Ugonjwa mkali wa wastani au mkubwa, na au bila homa (ahirisha hadi kupona)
Ujauzito (chanjo hai — epuka isipokuwa hatari ya maambukizi ni kubwa sana)
Matibabu ya dawa za kupunguza kinga kwa kipimo kikubwa — subiri angalau miezi 3 baada ya kuacha matibabu
Baada ya kupokea immunoglobulini au damu — subiri angalau wiki 4
Tahadhari maalum kwa Afrika Mashariki:
VVU ni kawaida katika eneo hili — tathmini CD4 kabla ya kutoa chanjo kwa watu wanaoishi na VVU
Wizara ya Afya ya Tanzania inapendekeza uchunguzi wa VVU kabla ya chanjo kwa watu wenye hatari kubwa
Watu wenye VVU na CD4 ≥200 wanaweza kupokea chanjo kwa ushauri wa daktari
Athari za kawaida (zinajitokeza kwa 10-30% ya waliopewa chanjo):
Maumivu, uwekundu, na uvimbe kwenye sehemu ya sindano (siku 1-3)
Maumivu ya kichwa ya wastani
Maumivu ya misuli na viungo
Homa nyepesi (kawaida chini ya 38.5°C)
Uchovu na malaise kwa siku 2-5 baada ya chanjo
Athari zisizo za kawaida (zinajitokeza kwa <5%):
Kichefuchefu na kutapika
Upele wa ngozi au urticaria ya wastani
Maumivu ya tumbo
Kupungua kwa hamu ya kula
Athari nadra lakini za hatari (tahadhari maalum):
Ugonjwa wa neva unaohusishwa na chanjo ya homa ya manjano (YEL-AND): 0.4-0.8 kwa kila dozi 100,000. Dalili: homa kali, maumivu ya kichwa makali, hali ya kuchanganyikiwa, kupooza, ugonjwa wa Guillain-Barré. Hatari kubwa zaidi kwa watu wenye umri >60.
Ugonjwa wa viungo vya ndani unaohusishwa na chanjo (YEL-AVD): 0.3-0.4 kwa kila dozi 100,000. Dalili zinafanana na homa ya manjano yenyewe — kushindwa kwa ini, figo, na mfumo wa damu. Kiwango cha vifo ni ~60%. Hatari kubwa zaidi kwa watu wenye umri >60 na wale wanaopewa chanjo kwa mara ya kwanza.
Tahadhari ya WHO AFRO:
Kituo cha chanjo kinapaswa kuwa na dawa za dharura (adrenaline/epinephrine) kwa matibabu ya anafylaksia
Watu waliopewa chanjo wanapaswa kusubiri angalau dakika 30 baada ya chanjo kwa ufuatiliaji
Ripoti athari zozote kali kwa TFDA (Tanzania) au PPB (Kenya)
Ratiba ya dozi:
Dozi moja ya 0.5 ml inatosha kutoa kinga ya maisha yote (WHO 2016)
Njia: sindano chini ya ngozi (subcutaneous) katika sehemu ya juu ya mkono (deltoid)
Umri wa kuanzia: miezi 9 (EPI Afrika Mashariki), miezi 6 katika hali za dharura za mlipuko
Muda wa kutoa chanjo:
Angalau siku 10 kabla ya kuingia eneo lenye hatari (Cheti cha ICV kinaanza kutumika siku ya 10 baada ya chanjo ya kwanza)
Kwa chanjo ya nyongeza: cheti kinatumika mara moja
Ratiba ya EPI katika Afrika Mashariki:
Tanzania: chanjo ya homa ya manjano imetolewa kama sehemu ya EPI katika mikoa ya hatari tangu 2013
Kenya: iliyojumuishwa katika EPI mwaka 2022 kwa maeneo yenye hatari (Kaunti za Magharibi na Rift Valley)
Uganda: kampeni za nyongeza za mara kwa mara tangu mlipuko wa 2016
Chanjo zinatolewa bure kupitia mpango wa EPI unaosaidiwa na Gavi
Maelekezo ya kiutawala:
Yeyusha chanjo kwa kuongeza 0.5 ml ya kiyeyusho (diluent) kilichotolewa
Changanya kwa upole — usitikise kwa nguvu
Tumia sindano mpya kwa kila mtu
Rekodi nambari ya kundi (batch number) na tarehe ya kumalizika kwenye Cheti cha ICV
Muhuri wa kituo na sahihi ya mtoa chanjo inahitajika kwenye cheti
Kampeni za mlipuko:
WHO AFRO inapendekeza matumizi ya kipimo kidogo cha dharura (1/5 ya dozi ya kawaida, yaani 0.1 ml chini ya ngozi) wakati wa mlipuko mkubwa na uhaba wa chanjo
Kipimo hiki kinaonyesha ufanisi wa kinga kwa angalau miezi 12
Mkakati huu ulitumika kwa mafanikio katika mlipuko wa Kinshasa, DRC mwaka 2016
Ufanisi wa kinga:
Dozi moja ya chanjo ya homa ya manjano ina ufanisi wa ≥99% katika kuzuia ugonjwa
Kingamwili za kuzuia (neutralizing antibodies) zinapatikana kwa >90% ya waliopewa chanjo ndani ya siku 10 na kwa >99% ndani ya siku 30
Ubadilishaji wa serolojia (seroconversion) kwa watu wenye kinga kamili ni 95-100%
Muda wa kinga:
Tafiti za muda mrefu zinaonyesha kwamba kinga inaendelea kwa angalau miaka 35-40 na huenda maisha yote
WHO ilisasisha mapendekezo yake mwaka 2013 (yaliyoidhinishwa rasmi mwaka 2016) kutangaza kuwa dozi moja ya chanjo inatoa kinga ya maisha yote
Hata hivyo, baadhi ya nchi bado zinahitaji nyongeza ya miaka 10 — angalia mahitaji ya kila nchi
Ufanisi kwa vikundi maalum:
Watu wanaoishi na VVU wenye CD4 ≥200: ubadilishaji wa serolojia ni ~70-80% (dhaifu kuliko watu wenye kinga kamili)
Watoto wenye umri wa miezi 9-12: ubadilishaji wa serolojia ni ~85% (kiasi kidogo kuliko watu wazima)
Watu wenye umri >60: mwitikio wa kinga ni mzuri lakini hatari ya athari kali ni kubwa zaidi
Athari ya kampeni za chanjo katika Afrika Mashariki:
Kampeni ya chanjo ya Uganda 2016-2017 ilizuia mlipuko mkubwa na kupunguza visa kwa >95%
Gavi imewezesha ununuzi wa zaidi ya dozi milioni 500 za chanjo ya homa ya manjano kwa nchi za Afrika tangu 2006
Mpango wa "Eliminate Yellow Fever Epidemics" (EYE) wa WHO unalenga kufikia kinga ya 80% katika nchi 40 za hatari ifikapo 2026
Proper vaccine storage is critical for maintaining potency and efficacy.
Unopened vaccine (lyophilized powder):
Temperature: 2°C to 8°C (35°F to 46°F); aim for 5°C (41°F)
Protection from light: Keep in original packaging
Duration: Until expiration date on vial
Freezing: Must not be frozen
Active Ingredient:
Yellow fever virus 17D-204 strain (live, attenuated) – minimum 1000 international units (IU) per 0.5 mL dose (equivalent to ≥4.74 log₁₀ plaque-forming units)
Produced in specified pathogen-free (SPF) chicken embryos, free of avian leukosis virus
Non-medicinal Ingredients (Excipients):
Sorbitol (stabilizer)
Gelatin (stabilizer)
Sodium chloride
L-Histidine hydrochloride
L-Alanine
Potassium chloride
Disodium phosphate dihydrate
Potassium dihydrogen phosphate
Calcium chloride
Magnesium sulfate
Lactose (in some formulations)
Water for injection
Notable absence:
No preservatives (sodium thimerosal or other antimicrobial agents) are added
Physical form:
Lyophilized (freeze-dried) powder supplied in hermetically sealed vials under nitrogen atmosphere
Reconstituted vaccine: slight pink-brown suspension
Mwingiliano na chanjo nyingine hai:
Chanjo za hai za sindano (kama MMR, varicella, BCG) zinapaswa kutolewa siku moja au kutenganishwa kwa angalau wiki 4. Hii ni kwa sababu chanjo mbili hai zinaweza kupunguza mwitikio wa kinga ikiwa zitatolewa kwa karibu sana.
Chanjo ya OPV (Chanjo ya Polio ya Mdomo): inaweza kutolewa siku yoyote kwa sababu ni chanjo ya mdomo, si ya sindano
BCG: ikiwa chanjo zote mbili zinahitajika (kwa mfano, kwa mtoto wa miezi 9 katika EPI), zinaweza kutolewa siku moja katika sehemu tofauti za mwili
Mwingiliano na chanjo zisizo hai:
Chanjo zisizo hai (kama chanjo ya homa ya ini A/B, typhoid ya sindano, meningococcal, polio ya IPV) zinaweza kutolewa wakati wowote — hakuna mwingiliano wa kliniki
Chanjo ya COVID-19 (mRNA au vektori): WHO inapendekeza kwamba inaweza kutolewa wakati wowote bila muda wa kusubiri
Mwingiliano na dawa:
Immunoglobulini na bidhaa za damu: zinaweza kupunguza mwitikio wa chanjo. Subiri angalau wiki 4 baada ya immunoglobulini kabla ya kutoa chanjo ya homa ya manjano, au wiki 2 baada ya chanjo kabla ya kutoa immunoglobulini
Dawa za kupunguza kinga (corticosteroids kwa kipimo ≥20 mg/siku ya prednisone kwa ≥wiki 2, dawa za kibayolojia kama anti-TNF): chanjo ni kizuizi — subiri angalau miezi 3 baada ya kuacha matibabu
Dawa za kuzuia malaria: hakuna mwingiliano — chanjo na dawa za kuzuia malaria zinaweza kutumika pamoja
Muhimu kwa Afrika Mashariki: Wasafiri wengi wanahitaji chanjo ya homa ya manjano pamoja na chanjo nyingine za safari. Ratiba ya kawaida inayopendekezwa na Wizara ya Afya ni kutoa chanjo zote zinazohitajika siku moja katika sehemu tofauti za sindano.
Recommendation: Yellow fever vaccine should be avoided during pregnancy unless travel to a high-risk yellow fever-endemic area is unavoidable and cannot be postponed, and a high level of protection against mosquito bite exposure is not feasible.
Rationale: Wild yellow fever virus can cause severe infection in pregnancy and has been associated with fetal transmission and poor outcomes. However, the live attenuated vaccine virus carries theoretical risk, particularly in the first trimester. Limited data from surveillance of several hundred women who inadvertently received yellow fever vaccine during pregnancy have not demonstrated significant adverse fetal outcomes, suggesting that inadvertent vaccination during pregnancy is not an indication for pregnancy termination.
Special considerations:
Seroconversion rates (antibody response) following vaccination are lower in pregnant women compared to non-pregnant individuals; post-immunization serology (blood test to confirm immunity) may be considered
Individual risk assessment must carefully weigh the risk of yellow fever infection (which carries substantial maternal and fetal morbidity and mortality) against theoretical vaccine risks
If vaccination is deemed necessary, it should ideally be administered in the second or third trimester, though the vaccine can be given at any stage if infection risk is high
Healthcare providers should document the indication for vaccination and counsel women regarding theoretical risks
Women of childbearing potential should be counseled to avoid pregnancy for 2 months following yellow fever vaccination, though data do not support this as a strict requirement
Recommendation: Yellow fever vaccination should generally be avoided in women who are actively breastfeeding, particularly those breastfeeding infants under 9 months of age.
Rationale: Three documented cases of vaccine-strain yellow fever virus transmission through breast milk have been reported, resulting in meningoencephalitis in exclusively breastfed infants whose mothers received yellow fever vaccine during their infants' first month of life. Although the exact mode of transmission has not been definitively established, the risk of vaccination during breastfeeding is considered a precaution rather than an absolute contraindication.
Age 6 months to 9 months:
Vaccination is contraindicated in routine circumstances due to increased risk of vaccine-associated encephalitis (YEL-AND). During the pre-restriction era (1950s), 15 encephalitis cases were reported in infants, with 13 (87%) occurring in infants under 4 months and all cases occurring in infants under 7 months. The risk of YEL-AND is inversely proportional to age in this age group.
Vaccination may be considered only when travel to yellow fever-endemic areas is unavoidable and the risk of wild-type yellow fever infection is very high (such as during confirmed epidemics or outbreaks). Expert consultation is mandatory, and a thorough individual risk-benefit assessment must be documented.
Age 9 months to 2 years:
Vaccination is recommended for infants and young children traveling to yellow fever-endemic areas. However, immunogenicity studies demonstrate lower seroprotection rates in children vaccinated before age 2 years:
Seroprotection rate within 5 years post-vaccination: approximately 52% in children vaccinated before age 2 years
This is substantially lower than the >90% seroprotection rate in children vaccinated at age ≥2 years
Booster vaccination in early childhood: Children vaccinated before age 2 years are recommended to receive a reinforcing (booster) dose once they reach age 2 years or older, depending on planned travel to yellow fever-endemic areas. This recommendation is based on evidence of waning seroprotection 3 months to 5 years following primary vaccination in infants. Recent breakthrough infection data suggest this approach may enhance long-term protection.
Age ≥9 years to adolescence:
Children in this age group have immunogenicity and safety profiles similar to adults. Standard vaccination schedules and recommendations apply. A single dose provides sustained protective immunity.
General pediatric considerations:
The vaccine is well-tolerated in children
Mild systemic adverse events (fever, headache, myalgia) are reported in 20–40% of younger vaccinees, with rates typically lower in older children than infants
Serious adverse events are rare in children, with the exception of increased risk in the 6–9 months age group
Vaccination in children can be given concurrently with routine immunizations at separate injection sites
Travel-related mosquito bite prevention is essential for all children, especially those too young for vaccination or in the precautionary age groups
Recommendation: Yellow fever vaccination for individuals aged 60 years and older requires individualized risk-benefit assessment. Vaccination should only be administered when there is a significant and unavoidable risk of acquiring yellow fever infection based on travel itinerary and duration in endemic areas.
No specific cases of overdose with yellow fever vaccine have been documented in the medical literature. The vaccine is supplied as a single-dose vial containing 0.5 mL (one dose), and multi-dose vials are used in limited circumstances under strict medical supervision.
Tathmini ya hatari na faida:
Watu wenye umri zaidi ya miaka 60 wanaopewa chanjo kwa mara ya kwanza: hatari kubwa zaidi ya YEL-AVD na YEL-AND — tathmini makini ya uwiano wa hatari na faida inapaswa kufanywa
Watu wanaoishi na VVU wenye CD4 kati ya 200-499: chanjo inaweza kutolewa lakini mwitikio wa kinga unaweza kuwa dhaifu — fikiria kupima kingamwili baada ya wiki 4
Wanawake wanaonyonyesha: kesi za nadra za maambukizi ya virusi ya chanjo kupitia maziwa ya mama zimeripotiwa — ni bora kuahirisha chanjo hadi mtoto awe na umri wa miezi 9+
Ujauzito:
WHO inapendekeza kuepuka chanjo wakati wa ujauzito kwa sababu ni chanjo hai
Hata hivyo, katika hali ya mlipuko au safari ya dharura kwenda eneo lenye maambukizi makubwa, faida zinaweza kuzidi hatari — uamuzi wa daktari unahitajika
Wanawake wa umri wa kuzaa wanapaswa kusubiri angalau mwezi 1 baada ya chanjo kabla ya kupata mimba
Mzio wa mayai:
Watu wenye mzio mdogo wa mayai (urticaria tu) wanaweza kupewa chanjo chini ya usimamizi wa daktari na kipimo cha ngozi (skin test) kabla
Watu wenye historia ya anafylaksia kwa mayai hawapewi chanjo — wanapaswa kupata barua ya msamaha (waiver letter)
Hifadhi na utawala:
Chanjo inapaswa kuhifadhiwa kwa +2°C hadi +8°C (mlolongo wa baridi)
Baada ya kuyeyushwa, chanjo inapaswa kutumika ndani ya saa 1
Chanjo inapaswa kutolewa tu katika vituo vilivyoidhinishwa na Wizara ya Afya (Yellow Fever Vaccination Centres)
Cheti cha Kimataifa cha Chanjo (ICV) kinatumika maisha yote kulingana na marekebisho ya WHO 2016
| Kipimo | Siku tangu iliyotangulia | Kipindi cha umri |
|---|---|---|
| Kipimo 1 | — | 9 miezi+ |
Unajua chanjo unayohitaji? Vizuri. Hujui? Tuambie tu unaenda wapi — tutapata chanjo zinazofaa na kliniki. Bure, bila masharti.
Maudhui katika ukurasa huu ni kwa madhumuni ya habari na elimu pekee. Hayaundi ushauri wa kitabibu, utambuzi, au mapendekezo ya matibabu. Ikiwa una wasiwasi wa kiafya, wasiliana na mtaalamu wa afya aliyeidhinishwa. Medova si mtoa huduma za matibabu.
Masharti kamili ya matumizi