Infectious diseases pose a major threat to elderly populations. Streptococcus pneumonia bacteria, influenza-causing viruses, and COVID-19 viruses cause three pathologies in the respiratory system with similar symptoms, transmission routes, and risk factors. Our study aimed to evaluate the effects of pneumococcal, influenza, and COVID-19 vaccinations on the status of COVID-19 hospitalization and progression in people over 65 years of age living in nursing homes. This study was performed in all nursing homes and elderly care centers in the Uskudar district of Istanbul.The diagnosis rate of COVID-19 was determined as 49%, the rate of hospitalization as 22.4%, the rate of hospitalization in the intensive care unit as 12.2%. The rate of intubation was determined as 10.4%, the rate of mechanical ventilation as 11.1% and the rate of COVID-19 related mortality rate as 9.7%. When the factors affecting the diagnosis of COVID-19 were examined, the presence and dose of COVID-19 vaccine was protective. When the factors affecting hospitalization status were examined, male sex and presence of chronic disease were risk factors; four doses of COVID-19 vaccine and influenza vaccine and pneumococcal vaccine together with COVID-19 vaccine were protective. When the factors affecting COVID-19-related death were examined, the male sex was a risk factor; the pneumococcal and influenza vaccine together with COVID-19 vaccine were protective. Our results revealed that the availability of influenza and pneumococcal vaccines positively impacted the progression of COVID-19 disease in the elderly population living in nursing homes.