Vaccination Effectiveness against Human Papillomavirus in Kazakhstan.

ABSTRACT

OBJECTIVE: The purpose was to determine the effectiveness of human papillomavirus immunization and its impact on cervical cancer development in Kazakhstan. METHODS: The current research is a case-control study with two groups a main group and a control group. A total of 725 subjects participated in the research. RESULTS: The association between vaccination and cervical cancer development was calculated both for the two groups as a whole and for individual patients, who were selected based on criteria of residence, presence of immunodeficiency or chronic cardiac or renal pathology, as well as analysis of age at which the vaccine dose was received. There was a statistically significant association between the absence of the human papillomavirus vaccine and the risk of cervical cancer in all groups. When considering the entire cohort, the chance of finding a risk factor (lack of vaccination) was almost 7 times higher in the main group than in the control group. Thus, an association between vaccination and cervical cancer risk was found in each of the pairs of subjects. CONCLUSION: The effectiveness of vaccination in preventing cervical cancer was not observed in patients who were vaccinated after 18 years of age, while most patients in the control group were vaccinated in their teens. The practical significance of the research is not only to further study the problem of human papillomavirus (HPV) vaccination in Kazakhstan but also to popularize HPV immunization to prevent cervical cancer (CC).