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With increasing numbers of vaccine-breakthrough infections worldwide, assessing the immunogenicity of vaccinated health-care workers that are frequently exposed to SARS-CoV-2-infected individuals is important. In this study, neutralization titers against SARS-CoV-2 were assessed one month after completed prime-boost vaccine regimens in health-care workers vaccinated with either mRNA–mRNA (Comirnaty^®, BioNTech-Pfzier, Mainz, Germany/New York, NY, USA, <i>n</i> = 98) or vector-based (Vaxzevria^®, Oxford-AstraZeneca, Cambridge, UK) followed by mRNA-based (Comirnaty^® or Spikevax^®, Moderna, Cambridge, MA, USA) vaccines (<i>n</i> = 16). Vaccine-induced neutralization titers were compared to time-matched, unvaccinated individuals that were infected with SARS-CoV-2 and presented with mild symptoms (<i>n</i> = 38). Significantly higher neutralizing titers were found in both the mRNA–mRNA (ID₅₀: 2525, IQR: 1667–4313) and vector–mRNA (ID₅₀: 4978, IQR: 3364–7508) prime-boost vaccine regimens when compared to SARS-CoV-2 infection (ID₅₀: 401, IQR: 271–792) (<i>p</i> < 0.0001). However, infection with SARS-CoV-2 induced higher titers when compared to a single dose of Vaxzevria^® (<i>p</i> = 0.0072). Between mRNA–mRNA and vector–mRNA prime-boost regimens, the vector–mRNA vaccine regimen induced higher neutralization titers (<i>p</i> = 0.0054). Demographically, both age and time between vaccination doses were associated with vaccine-induced neutralization titers (<i>p</i> = 0.02 and <i>p</i> = 0.03, respectively). This warrants further investigation into the optimal time to administer booster vaccination for optimized induction of neutralizing responses. Although anecdotal (<i>n</i> = 3), those with exposure to SARS-CoV-2, either before or after vaccination, demonstrated superior neutralizing titers, which is suggestive of further boosting through viral exposure.