Final answer:
The reemergence of infectious and parasitic diseases includes those that were dormant or under control but are now resurfacing, such as bubonic plague and tuberculosis. The WHO monitors these diseases, and many emerging infectious diseases are zoonotic. Control and surveillance are essential to prevent outbreaks.
Step-by-step explanation:
Reemergence of Infectious and Parasitic Diseases
Infectious and parasitic diseases that were once under control, or dormant, are now reemerging globally. Instances such as the bubonic plague demonstrate diseases that return more virulent after periods of dormancy. Others, like tuberculosis, were never fully eradicated and have resurfaced, often in areas with dense populations and high numbers of immunocompromised individuals. The World Health Organization (WHO) monitors the reemergence of diseases, including viral diseases like dengue fever and yellow fever, and bacterial diseases such as diphtheria, cholera, and bubonic plague. Factors contributing to the reemergence of diseases include environmental changes, pathogen evolution, host population dynamics, poverty, political unrest, and the appearance of antibiotic-resistant strains.
Diseases like Ebola and various forms of influenza have shown substantial increases in incidence or threats of spreading. Approximately 75 percent of these emerging infectious diseases are zoonotic, meaning they originate in animals but can be transmitted to humans. Surveillance and control efforts are vital to prevent large-scale outbreaks, such as the one in Surat, India, in 1994 due to the bubonic plague exacerbated by an earthquake, insufficient healthcare, and urban infrastructure failures.