Article 8 of the Convention for the Protection of Human Rights and Fundamental Freedoms (ECHR) protects individuals from the so-called involuntary medical treatments within the framework of the right to respect for private life. Given that the rights guaranteed under Article 8 are not absolute but qualified rights (which can be limited for the reasons enlisted in Article 8, paragraph 2), it is crucial to examine the necessity and proportionality of the measures adopted by the state when deciding on the admissibility of these limitations. In its jurisprudence, the European Court of Human Rights (ECtHR) addressed the issue of involuntary medical treatment in a number of cases, but the issue of compulsory vaccination (of children) was addressed in only one case, Vavrička and others v the Czech Republic (2021). The decision was rendered in April 2021, at the peak of the fight against the pandemic caused by the COVID-19 disease. Having in mind the circumstances at the moment when the decision was made, the fact that the case was decided by the Grand Chamber, and the fact that applications against Greece and France had already been lodged with the Court concerning compulsory vaccination against the COVID-19 disease, it is difficult to avoid the impression that the Court had the aforesaid applications in mind when addressing the issue in Vavrička and others. The importance of the Court’s decision in the case Vavrička and others and the criteria stated therein for determining the proportionality and necessity of the measure of compulsory vaccination, as well as the width of the margin of appreciation enjoyed by states, is therefore evident. The paper also presents the decisions of the Constitutional Court of Croatia on the issue of compulsory vaccination of children. For the purpose of projecting the direction in which the ECtHR will go when deciding on such cases, the author elaborates on the aforesaid applications before the Court, where the applicants claimed the violation of their Article 8 right due to the introduction of compulsory vaccination against the COVID-19 disease for certain categories of employees. Finally, although the status of compulsory vaccination against the COVID-19 disease has not been resolved before the Court yet, we may draw certain conclusions on the basis of the current direction of the Court’s legal reasoning on the proportionality of the measure of compulsory vaccination of children. For this reason, great attention will be given to the doctrine of the margin of appreciation, the concept of “weighing” the rights of individuals against the protection of certain legitimate goals, and the examination of necessity and proportionality by the ECtHR.