the pan american health organization (paho) works with the countries of the americas to improve the health and quality of life of their populations. founded in 1902, it is the world’s oldest international public health agency. it serves as the regional office of who for the americas and is the specialized health agency of the inter-american system.

the united nations agency working to promote health, keep the world safe and serve the vulnerable.

cdc is the nation’s leading science-based, data-driven, service organization that protects the public’s health. for more than 70 years, we’ve put science into action to help children stay healthy so they can grow and learn; to help families, businesses, and communities fight disease and stay strong; and to protect the public’s health.

elsevier is a global information analytics company that helps institutions and professionals progress science, advance healthcare and improve performance

find information on health conditions, wellness issues, and more in easy-to-read language on medlineplus, the up-to-date, trusted health information site from the nih and the national library of medicine.