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HIV/AIDS Projection in Tamilnadu Using Back Calculation Method


Affiliations
1 Department of Statistics, National Institute for Research in Tuberculosis, ICMR, Chennai – 600031, India
2 Department of Mathematics, Sir Theagaraya College, Chennai – 600 021, India
3 Department of Statistics, Dr. Ambedkar Government Arts College, Chennai - 600 039, India
 

The current prevalence of HIV infection and the corresponding pattern of incidence from the beginning of the epidemic to the present time are mainly estimated by means of back-calculation method. This back-calculation method reconstructs the past pattern of HIV infection and predicts the future number of AIDS cases with the present infection status. The basic data required for back-calculation methodology is the number of AIDS cases over a period of time. TANSACS publishes the reported number of AIDS cases in Tamil Nadu. In this paper, the various approaches for modeling the incubation distribution are compared using real data under various infection density distributions. The projected minimum and maximum AIDS cases in Tamil Nadu, a southern state of India, based on the reported data are 3702712 and 6936047 respectively. These estimates are based on the unadjusted AIDS incidence data. The purpose of this paper is to review the contribution of back-calculation method to our understanding of the AIDS and to summarize and interpret the epidemiological findings.

Keywords

HIV/AIDS,Incubation Period, Estimation, Infection Distributions, Back Calculation
User

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  • HIV/AIDS Projection in Tamilnadu Using Back Calculation Method

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Authors

P. Venkatesan
Department of Statistics, National Institute for Research in Tuberculosis, ICMR, Chennai – 600031, India
D. Ramamurthy
Department of Mathematics, Sir Theagaraya College, Chennai – 600 021, India
N. Sundaram
Department of Statistics, Dr. Ambedkar Government Arts College, Chennai - 600 039, India

Abstract


The current prevalence of HIV infection and the corresponding pattern of incidence from the beginning of the epidemic to the present time are mainly estimated by means of back-calculation method. This back-calculation method reconstructs the past pattern of HIV infection and predicts the future number of AIDS cases with the present infection status. The basic data required for back-calculation methodology is the number of AIDS cases over a period of time. TANSACS publishes the reported number of AIDS cases in Tamil Nadu. In this paper, the various approaches for modeling the incubation distribution are compared using real data under various infection density distributions. The projected minimum and maximum AIDS cases in Tamil Nadu, a southern state of India, based on the reported data are 3702712 and 6936047 respectively. These estimates are based on the unadjusted AIDS incidence data. The purpose of this paper is to review the contribution of back-calculation method to our understanding of the AIDS and to summarize and interpret the epidemiological findings.

Keywords


HIV/AIDS,Incubation Period, Estimation, Infection Distributions, Back Calculation

References





DOI: https://doi.org/10.17485/ijst%2F2012%2Fv5i8%2F30531