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. 2010 Dec;86 Suppl 2(Suppl_2):ii16-21.
doi: 10.1136/sti.2010.044222.

The Spectrum projection package: improvements in estimating incidence by age and sex, mother-to-child transmission, HIV progression in children and double orphans

J Stover  1 , P Johnson, T Hallett, M Marston, R Becquet, I M Timaeus
Affiliations

The Spectrum projection package: improvements in estimating incidence by age and sex, mother-to-child transmission, HIV progression in children and double orphans

J Stover et al. Sex Transm Infect. 2010 Dec.

Abstract

Background: The Spectrum program is used to estimate key HIV indicators from the trends in incidence and prevalence estimated by the Estimation and Projection Package or the Workbook. These indicators include the number of people living with HIV, new infections, AIDS deaths, AIDS orphans, the number of adults and children needing treatment, the need for prevention of mother-to-child transmission and the impact of antiretroviral treatment on survival. The UNAIDS Reference Group on Estimates, Models and Projections regularly reviews new data and information needs, and recommends updates to the methodology and assumptions used in Spectrum.

Methods: The latest update to Spectrum was used in the 2009 round of global estimates. This update contains new procedures for estimating: the age and sex distribution of adult incidence, new child infections occurring around delivery or through breastfeeding, the survival of children by timing of infection and the number of double orphans.

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Conflict of interest statement

Competing interests: None.

Figures

Figure 1
Figure 1
Inputs, outputs and process of the demographic and AIDS modules in Spectrum.
Figure 2
Figure 2
Distribution of new HIV infections by age for males (left) and females (right) in high-prevalence countries. AIS, AIDS Indicators Survey; DHS, Demographic and Health Surveys; SBS, Sexual Behaviour Survey.
Figure 3
Figure 3
Patterns of the distribution of new HIV infections by age and type of epidemic. Conc, low level and concentrated epidemics; F, female; Gen, generalised epidemics; IDU, injecting-drug-user-driven epidemics; M, male.
Figure 4
Figure 4
Comparison of the age pattern of prevalence from Spectrum projection from 1970 (dashed lines) to survey results (solid lines) in Malawi 2004 (left) and Swaziland 2006/2007 (right). DHS, Demographic and Health Surveys.
Figure 5
Figure 5
Proportion of HIV-infected children surviving by time since infection for children infected around the time of birth (early infection, solid line) or later through breastfeeding (late infection, dashed line).
See this image and copyright information in PMC

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References

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