Final answer:
Sudden Infant Death Syndrome (SIDS) and unintentional injuries are leading causes of death among children in the U.S., while pediatric cancers also contribute to mortality. The leading causes vary significantly compared to those in low-income countries.
Step-by-step explanation:
The leading cause of death among children in the U.S. has varied causes depending on age groups. For infants, Sudden Infant Death Syndrome (SIDS) is one of the leading causes, while for children older than one year, unintentional injuries such as motor vehicle crashes and drowning are predominant. Disorders such as congenital anomalies and cancers also contribute to childhood mortality rates.
Notably, pediatric cancer, with varying types including leukemia and brain tumors, comprises a significant threat to child health. For children under five, pediatric cancer, congenital defects, and in some cases infections, assuming a more indirect role, are leading contributors. It's important to note the distinction between low-income countries where preventable diseases like pneumonia, diarrhea, and malnutrition-related complications lead, as opposed to higher-income settings where the epidemiological landscape shifts towards non-communicable diseases and injuries.