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Annual Congress of Malaysian Thoracic Society
OP 2
Assessing Impact On Tuberculosis Interventions In Malaysia:
A Mathematical Modelling Application For Outbreak And Control
Nurhuda Ismail 1, 2 , Awang M Bulgiba 2 , Nicolaas J D Nagelkerke 3 , Omar Awang 2
1
University of Technology MARA Sungai Buluh Campus, Selangor, Malaysia
2
University of Malaya, Kuala Lumpur, Malaysia
3
United Arab Emirates University, Al-Ain, United Arab Emirates
Tuberculosis remains as one of the highest unresolved disease burden among re-emerging diseases in
Malaysia for the last twenty years. With current treatment protocol emphasising treatment of infectives, we
seek to find if combination treatment of these active cases with Isoniazid Preventive Therapy for high risk latent
tuberculosis infection groups among non-HIV population would give greater impact on reducing incidence.
We present a deterministic compartmental age-structured tuberculosis model that assumes latently infected
individuals develop active disease as a result of primary infection, endogenous reactivation and exogenous
reinfection. We start by formulating and analysing the model without any intervention strategy, and extend
to incorporate preventive therapy and treatment of infectives. Epidemic thresholds, model equilibria and
stabilities are determined and analyzed. Reproduction numbers are compared to assess possible community
benefits achieved by treatment of infectives, preventive therapy and a holistic approach of combination of
both intervention strategies. The model further quantifies the effectiveness of preventive therapy for early
latent tuberculosis infection and demonstrates how effective it has to be to eliminate tuberculosis, when use
in conjunction with treatment for active tuberculosis. Analyses show treatment of infectives more effective
in the first years of implementation of preventive therapy as treatment results in clearing active tuberculosis
immediately, there after preventive therapy will do better in controlling the number of infectives due to reduced
progression to infectious state. Our model suggests Isoniazid Preventive Therapy which identify and treat
persons recently infected may have substantial effect on controlling tuberculosis epidemics in Malaysia.
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