Final answer:
In the 21st century, major community and public health problems include obesity, water pollution, access to healthcare, infectious diseases, and natural disasters.
Step-by-step explanation:
In the 21st century, some of the major community and public health problems facing both the US and the world include obesity, water pollution, access to healthcare, infectious diseases, and natural disasters.
Obesity: Obesity rates have been rapidly increasing globally, leading to various health problems such as heart disease, diabetes, and musculoskeletal disorders.
Water Pollution: Chemical pollution from various sources threatens global water quality, affecting the availability of safe drinking water and contributing to health issues.
Access to Healthcare: In low-income countries, challenges in accessing medical education and patients exacerbate the issue of healthcare provision.
Infectious Diseases: Diseases like Ebola, HIV/AIDS, and the recent COVID-19 pandemic have posed significant challenges to global public health.
Natural Disasters: As human populations expand in vulnerable areas, the frequency of natural disasters has increased, leading to a higher number of people affected and in need of healthcare.