TB PREVENTION by Assoc. Prof. Dr. Nik Sherina Haidi Hanafi

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LEARNING OBJECTIVES

• To learn on who should be screened for TB • To learn on the available screening tests • To learn on the TB preventive strategies for healthcare workers 2

CONTENT

• Screening of contacts • Screening tests • Preventive strategies for health care workers 3

SCREENING

• Objectives of screening – Early detection of TB – Reduction of TB transmission • Persons to screen – Contacts of index TB patients – Index patients: both smear positive & negative cases 4

SCREENING

• Contact screening: – Risk of acquiring all types of TB is higher amongst contacts compared to non contacts (OR=4.5, 95% CI 4.3 to 4.8) Morrison J et al., Lancet Infect Dis, 2008 • • Contacts Close contacts No universal definition 5 5 5

SCREENING

• Variable definition of contacts: – family members living in the same room with the index cases for more than 30 days Noertjojo K et al., Int J Tuberc Lung Dis, 2002 – family members or other people who lived with smear-positive PTB cases for more than half a year Hou SY et al. ,Chin J Antituberculosis, 2006 6

SCREENING

• Contacts have varying risks: – Diabetes (OR=10.2, 95% CI 3.0 to 34.8) – Cavitation in index patients (OR=1.6, 95% CI 1.1 to 2.2) – More than 100 AFB/field (OR=1.8, 95% CI 1.2 to 2.8) – Household contact at night (OR=2.1, 95% CI 1.3 to 3.2) – Actively smoking (OR=1.6, 95% CI 1.1 to 2.4) Aissa K et al., Am J Respir Crit Care Med, 2008 7

CPG MANAGEMENT OF TUBERCULOSIS (3 RD RDITION)

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SCREENING TESTS FOR CONTACTS & HIGH RISK GROUP

• Tests for asymptomatic individuals (alone or in combination): – CXR – Tuberculin skin test (TST) – IGRA • CXR & symptom screening (CFSW: cough, fever, night sweat & weight loss) increases the specificity of screening compared to symptom screening alone 1 Churchyard GJ et al, AIDS, 2010.

2 den Boon S et al., Int J Tuberc Lung Dis, 2006 11

SCREENING TEST

• A clinical scoring system is useful for the diagnosis of smear negative TB – CXR findings – Clinical features (haemoptysis, age >45 years, loss of weight, expectoration, apical infiltrate & miliary infiltrate) • AUC=0.83, 95% CI 0.74 to 0.90

1 Soto A et al., Braz J Infect Dis. 2008 2 Soto A et al., PLoS ONE, 2011 12

TUBERCULIN SKIN TEST (TST)

• • • • • • Most widely used - Mantoux test Preferred test in children <5 years of age Advantages – – Cheap Relatively easy to perform Disadvantages – Timescale – Defaulters – Reading of induration prone to subjective errors False positives – – NTM infection Previous BCG vaccination False negatives – – Compromised immune system Extensive TB (pulmonary or miliary) (paradoxical) 13

PREVENTION OF TB INFECTION AMONG HEALTHCARE WORKERS

• • • Process: Risk assessment - done to determine the risk of TB transmission at workplace Risk category Risk control – administrative controls – engineering controls – personal protective equipment 14

CPG MANAGEMENT OF TUBERCULOSIS (3 RD RDITION)

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TAKE HOME MESSAGES

• All TB contacts need to be screened.

• Certain groups are at higher risk of acquiring TB.

• Screening involves symptom screening, TST & CXR.

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THANK YOU

 [email protected]

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