Question

Identify scenarios that describe an emerging infectious disease.

1) Reported cases of Lyme disease in humans have increased steadily since its relatively recent recognition in 1976.
2) A peptide collected from the skin of an Indian frog kills methicillin-resistant Staphylococcus aureus.
3) The bacterium that causes tuberculosis has had known mortal effects on humans throughout human history.
4) An infectious fungus observed in the black poplar tree recently appeared in the Eastern cottonwood tree.
5) Malaria cases have increased exponentially due to malaria's resistance to drugs and mosquitoes' resistance to pesticides.

Answer 1

Emerging infectious diseases are those which show increased incidence or spread. Lyme disease, the spread of an infectious fungus to new tree species, and drug-resistant malaria are examples of such diseases. Scenarios 1, 4, and 5 correctly describe emerging infectious diseases.

Step-by-step explanation:

Emerging Infectious Diseases

An emerging infectious disease is an infection that has recently increased in incidence or geographic range, caused by either new or re-identified organisms. We can identify several scenarios that depict emerging infectious diseases:

• Increased cases of a disease since its recognition, such as Lyme disease since 1976, suggest it is an emerging disease.
• The appearance of an infectious agent in a new host species, like a fungus moving from black poplar to Eastern cottonwood trees.
• Increases in disease due to environmental changes leading to drug resistance, such as malaria showing resistance to drugs and mosquitoes becoming resistant to pesticides.

Antibiotic resistance is a global problem contributing to the emergence of diseases. Once manageable infections can return with drug-resistant strains, and new forms can spread internationally without regard for borders. Environmental toxicology and the study of environmental contaminants are crucial in understanding the health effects of exposure to such toxic agents and mitigation of these emerging infections.

Considering the provided scenarios, the first option (1) detailing the increase in reported cases of Lyme disease, and the fourth option (4) describing an infectious fungus appearing in a new tree species, are examples of emerging infectious diseases. The fifth option (5) involving malaria also represents an emerging disease, as it illustrates how environmental factors, like drug and pesticide resistance, are causing a resurgence. Meanwhile, the second (2) and third (3) options do not describe emerging infectious diseases as they do not meet the criteria of a substantial increase or threat thereof in affected populations, distribution, or magnitude.

The correct options that describe an emerging infectious disease scenario would be 1, 4, and 5.