Estimated rates of progression to disease.

<p>(A) The estimated rates of progression of infection with HPV-16, HPV-18 and other high-risk (OHR) HPV types to CIN1-type lesions. We compare the rates estimated from the longitudinal Swedescreen data with the model-based estimates of Jit et al. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0049614#pone.0049614-Jit1" target="_blank">[5]</a> and Van de Velde et al. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0049614#pone.0049614-VandeVelde1" target="_blank">[21]</a>. (B) The estimated rates of progression of CIN1-type lesions attributable to HPV-16, HPV-18 and other high-risk (OHR) HPV types to CIN2-type lesions. We compare the rates estimated from the longitudinal Swedescreen data with the model-based estimates of Jit et al. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0049614#pone.0049614-Jit1" target="_blank">[5]</a> and Van de Velde et al. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0049614#pone.0049614-VandeVelde1" target="_blank">[21]</a>.</p

Comparison of the estimated annual rates of clearance of initial infection between 13 high-risk HPV types and HPV-6 and -11.

<p>The vertical line signifies the median of the median rates for all fifteen types; horizontal bars represent the 95% posterior intervals.</p

Annual rates of clearance of HPV infection.

<p>(A) Comparison of the estimated annual rates of clearance of initial HPV-16 infection in this and six further studies. The vertical line signifies the median of the median values of all seven studies. (B) Comparison of the estimated annual rates of clearance of initial HPV-18 infection in this and five further studies. The vertical line signifies the median of the median values of all six studies. (C) Comparison of the estimated annual rates of clearance of initial HPV-31 infection in four further studies. The vertical line signifies the median of the median values of all five studies.</p

The predicted endemic prevalence of type-specific HPV infection in sexually active women and the observed prevalence in both women attending voluntary Chlamydia screening (solid dots) and those tested at baseline in the Swedescreen study (hollow dots).

<p>The median predicted prevalence for each type is represented by the solid curve and the turquoise bands represent the 50%, 70%, 90% and 95% posterior intervals.</p

Comparison of the estimated annual rates of waning immunity for 13 high-risk types of HPV with those estimated by Bogaards et al.

<p><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0049614#pone.0049614-Bogaards1" target="_blank">[<b>22</b>]</a><b>.</b> The vertical line signifies the average of the posterior median estimates across all types in both studies.</p

The assumed equivalence between histological and cytological test results used in estimating rates of disease progression and clearance.

<p>The assumed equivalence between histological and cytological test results used in estimating rates of disease progression and clearance.</p

The estimated annual rates of new partner acquisition for males and females in each of the three age and two sexual activity groups.

<p>The estimated annual rates of new partner acquisition for males and females in each of the three age and two sexual activity groups.</p

The estimated rates of transmissibility for thirteen high-risk HPV types and HPV-6 and -11.

<p>Results presented are the median and 95% posterior interval.</p

The <i>Susceptible-Infectious-Recovered-Susceptible</i> (SIRS) model of high-risk Human Papillomavirus (HPV) transmission and potential consequent progression to cervical cancer.

<p>Susceptible individuals become infected at a rate proportional to the force of infection λ. Following infection, they may progress in a stepwise fashion to neoplastic lesions of increasing severity (CIN1, CIN2, CIN3) and then to cancer (with rates ). Alternatively, they may spontaneously clear the infection from any pre-cancerous stage (with rates ). High-grade clinical lesions (CIN2 and CIN3) may be identified by cytological screening and successfully treated (at a rate π). Following viral clearance or successful treatment of lesions, women retain an immunity to re-infection with the same HPV type. This immunity wanes at rate κ, precipitating a return to the Susceptible compartment.</p

The estimated rates of progression and clearance of CIN1-type lesions in four high-risk HPV types.

<p>To facilitate comparison with other studies, the grouping OHR includes types -31 and -33. Results presented are the median and 95% adjusted bootstrap confidence interval. There were insufficient data available for non-16 types to be able to infer the progression rates of CIN3 to cancer and, in the case of HPV-18, the rate of progression from CIN2 to CIN3.</p