There are several factors that contribute to the emergence of infectious diseases, including:

1. Changes in the environment: Environmental changes, such as deforestation, climate change, and urbanization, can increase the risk of disease emergence by altering the habitat and behavior of animals, insects, and other disease vectors.
2. Changes in human behavior: Human activities, such as international travel and trade, can facilitate the spread of infectious diseases across borders. Population growth and migration, as well as changes in sexual and drug-use behavior, can also contribute to the emergence of new infections.
3. Microbial evolution: Microbes can evolve rapidly, developing new resistance mechanisms or becoming more virulent. This can lead to the emergence of new diseases or the re-emergence of previously controlled infections.
4. Inadequate public health infrastructure: Weak health systems can exacerbate the emergence and spread of infectious diseases. Inadequate surveillance, poor infection control practices, and limited access to vaccines and other preventive measures can all contribute to the emergence of EIDs.

Nurses play a critical role in preventing and controlling the spread of infectious diseases, including EIDs. They can promote infection prevention and control measures, such as hand hygiene and vaccination, and educate patients and communities about the risks and prevention of EIDs. Nurses can also collaborate with other healthcare professionals and public health authorities to monitor disease outbreaks, implement effective treatment and prevention measures, and advocate for strong public health infrastructure.