On the Elimination of Infections Related to Oncogenic Human Papillomavirus: An Approach Using a Computational Network Model

Abstract

Cervical cancer is the fourth most common malignancy in women worldwide, although it is preventable with prophylactic HPV vaccination. HPV transmission-dynamic models can predict the potential for the global elimination of cervical cancer. The random network model is a new approach that allows individuals to be followed, and to implement a given vaccination policy according to their clinical records. We developed an HPV transmission-dynamic model on a lifetime sexual partners network based on individual contacts, also accounting for the sexual behavior of men who have sex with men (MSM). We analyzed the decline in the prevalence of HPV infection in a scenario of 75% and 90% coverage for both sexes. An important herd immunity effect for men and women was observed in the heterosexual network, even with 75% coverage. However, HPV infections are persistent in the MSM population, with sustained circulation of the virus among unvaccinated individuals. Coverage around 75% of both sexes would be necessary to eliminate HPV-related conditions in women within five decades. Nevertheless, the variation in the decline in infection in the long term between a vaccination coverage of 75% and 90% is relatively small, suggesting that reaching coverage of around 70–75% in the heterosexual network may be enough to confer high protection. Nevertheless, HPV elimination may be achieved if men’s coverage is strictly controlled. This accurate representation of HPV transmission demonstrates the need to maintain high HPV vaccination coverage, especially in men, for whom the cost-effectiveness of vaccination is questioned.

A two-sex model of human papillomavirus infection: Vaccination strategies and a case study

“…This strategy indicates that high coverage in one gender can provide strong herd immunity for sexually transmitted diseases, which also agrees with the results in refs. [44,45].…”

“…The model can be extended to take into account more factors, such as age, sexual behavior and some other heterogeneous mixing. In particular, models with age structure would be more realistic to study the spread of sexually transmitted diseases such as HPV infection and its associated diseases due to the change of sexual behavior with age [44,45]. We have formulated two such models with age structure to study the dynamics of HPV-associated oropharyngeal cancer and cervical cancer in Texas [19,20].…”

“…Damm et al found that the cost-effectiveness of additional vaccination for boys was highly dependent on the coverage in girls [26]. Some other papers investigated the impact of HPV vaccines and proper vaccine distributions without considering cost-effectiveness [27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45]. Several of them suggested that girls-only policy was better than including boys, at least in the present situation [27][28][29][30][31].…”

“…However, Azevedo et al showed that without including men in a vaccination program the disease could only be controlled when more than 90% of women were vaccinated [32]. Muñoz-Quiles et al constructed a computational network model and found that HPV-related diseases in women would be eliminated within five decades if the vaccine coverage can achieve 75% for both females and males [44]. In addition, Bogaards et al found that giving vaccines to the gender with the highest prevaccine prevalence would most reduce the prevalence [28].…”

“…Waning immunity was also considered to be important, especially when studying persistent HPV infection and its associated cancer incidence [31,34]. The impact of HPV vaccination was also evaluated in the population of MSM [27,[44][45][46]. Díez-Domingo et al showed that MSM would not benefit by the herd immunity effect of vaccinating females [46].…”