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BACILLE CALMETTE-GUERIN DISEASE. L Pitso – University of Pretoria. 1. BACILLE CALMETTE-GUERIN VACCINE. Live attenuated Mycobacterium bovis WHO vaccination recommendation All neonates in areas of high prevalence of TB HIV exposure not an exclusion
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BACILLE CALMETTE-GUERIN DISEASE L Pitso – University of Pretoria 1
BACILLE CALMETTE-GUERIN VACCINE Live attenuated Mycobacterium bovis WHO vaccination recommendation All neonates in areas of high prevalence of TB HIV exposure not an exclusion Neonates with Symptomatic HIV disease excluded SA uses intradermal Darnish strain BCG 2
BCG RELATED COMPLICATIONS (BCG DISEASE) Injection site complication Adenitis Disseminated disease Accelerating HIV disease 3
BCG RELATED COMPLICATIONS (BCG DISEASE) Vaccine related Type of BCG strain Physical chemical property Bacillary load Patient related Immune characteristics Increased risk in immuno-compromised patient 4
TALBOT CLASSIFICATION Regional disease Extra-regional local disease Disseminated disease Other BCG syndromes 5
Problems with Talbot classification No accurate reflection of clinically relevant BCG disease categories in HIV infected children It does not incorporate standard Expanded Programme on Immunization definitions. Is not feasible to implement in routine clinical practice It is pre ARVT era 7
9 Adapted from Hesseling et al., 2006
Guidelines for the diagnosis of BCG disease in children Suspicion: <2year olds with right sided local or regional lesion High suspicion index of primary distant or disseminated BCG disease even in the absence of local or regional BCG in immuno-compromised children 10
SUGGESTED DIAGNOSTIC WORK-UP Hesseling et al., 2006 11
SUGGESTED DIAGNOSTIC WORK-UP...continued BCG confirmation: M. bovis confirmed by molecular or culture and biochemical methods. Hesseling et al., 2006 12
TREATMENT OF BCG DISEASE IN HIV UNINFECTED CHILDREN Hesseling et al., 2006 13
TREATMENT OF BCG DISEASE IN HIV-INFECTED OR IMMUNOCOMPROMISED CHILDREN Hesseling et al., 2006 14
TREATMENT OF BCG DISEASE IN HIV-INFECTED OR IMMUNOCOMPROMISED CHILDREN…continued Hesseling et al., 2006 15
To vaccinate or not to vaccinate • Non-HIV infected children • 67-79% protection TBM • 58-87% miliary disease • Pulmonary variable • <5% BCG disease ( congenital immunodeficiency) • HIV infected children • No evidence of any BCG induced-protection 16
Challenges with WHO BCG vaccination recommendation • Identifying HIV infection at birth • Most HIV transmission occur peri- or postpartum • Infected infants are usually asymptomatic at birth • Diagnosis by PCR only at 6 weeks at PMTC programme • Based on low perceived risk of serious adverse events • Immunized asymptomatic HIV infected infants at AIDS stage have increased risk • SA and Argentina studies 407-1300/100 000 • 75% mortality. 17
Revised WHO’s BCG vaccine policy of HIV exposed children (GACVS and SAGE) • Selective delayed vaccination • PMTC and vaccination working together • Vaccination at 10-14 weeks of age after negative PCR HIV • Combination with TB prophylactic treatment 18
The Union’s BCG Working Group • The BCG Working Group of the International Union against Tuberculosis and Lung Disease • Working Group of the Child Lung Health Organization 19
The Union assessment • Accept the revised vaccination policy • Challenges • Non vaccination of HIV–exposed non-infected infants • improved PMTC and maternal access to HAART will result in a very high number of exposed non infected children • The early use of HAART reduces the risk of BCG disease – delayed vaccination not being necessary 20
Conditions necessary for implementation of selective delayed BCG vaccination • High uptake of maternal HIV testing coupled with effective PMTC strategies, including maternal HAART • Early virological diagnosis of HIV infection in infants coupled with institution of HAART • Coordination of PMTC, vaccination and TB programmes to • Minimise loss to follow up • Implement alternative TB preventive strategies • Deliver successful vaccination following selective policy 21
Conclusion • The new revised policy is supported in areas that is feasible • Current universal BCG immunisation of infants continues in countries • Don’t meet the necessary conditions for revised version • High endemic for TB 22
REFERENCES World Health Organization. Revised BCG vaccination guidelines for infants at risk for HIV infection. Wkly Epidemiol Rec 2007;82:193-196. Strategic Advisory Group of Experts. Meeting of the Immunization Strategic Advisory Group of Experts, April 2007-Conclusions and recommendations. Wkly Epidemiol Rec 2007;82:181-193. Global Advisory Committee on Vacccine Safety. Meeting of the Global Advisory Committee on Vaccine Safety, 29-30 November 2006. wkly Epidemiol Rec 2007;82:18-24. Hasseling A C, Marais B J, Gie R P, et al. The risk of disseminated baccille Calmette-Guerin (BCG) disease in HIV-infected children. Vaccine 2007;25:14-18. Hasseling A C, Cotton M F, Fordham von Rey c, et al. Consensus statement on the revised World Health organization recommendations for BCG Vaccination in HIV-infected infants. Int J Tuberc Lung Dis 2008;12:1376-1379 23