Which of the following are public health activities pharmacists can perform?

A. Providing immunizations: Pharmacists play a key role in preventive care by administering vaccines such as influenza, COVID-19, and pneumococcal vaccines. This reduces disease transmission, contributes to herd immunity, and improves population-level health outcomes. B. Ensuring access to medications: Pharmacists facilitate medication access through dispensing, managing supply chains, assisting with insurance or affordability issues, and recommending alternatives. This supports continuity of care and prevents complications from untreated conditions. C. Counseling patients on safe and effective use of medications: Pharmacists provide essential education on dosing, side effects, drug interactions, and adherence. This improves therapeutic outcomes, reduces medication errors, and enhances patient safety at both individual and community levels. D. All of the above: Each option reflects a core public health function of pharmacists, including disease prevention, access to care, and patient education, all of which contribute to improved population health and reduced healthcare burden.