Final answer:
The World Health Organization (WHO) has increasingly focused on noncommunicable diseases and social determinants of health, as well as the monitoring and control of resurgent infectious diseases.
Step-by-step explanation:
In recent years, the World Health Organization (WHO) has been increasingly focusing on social determinants of health and noncommunicable diseases. The WHO is a critical agency under the United Nations, providing leadership in global health matters, shaping the health research agenda, and monitoring worldwide health trends. While the WHO continues to tackle infectious diseases, with some successes in reducing the incidence rates of diseases like malaria, tuberculosis, HIV/AIDS, their efforts are often challenged by population increases.
An important aspect of the WHO's work is epidemiology, which plays a key role in the prevention and control of diseases. The WHO has identified a resurgence of certain diseases that were historically catastrophic or have been controlled in certain regions, like dengue fever, yellow fever, diphtheria, cholera, and bubonic plague. The ongoing struggle against these diseases, both old and emerging, highlights the complexities of global health and the unending nature of this battle.