Question

Which of the following is a true bacterial disease?
A. Yellow fever
B. Plague
C. Mountain fever
D. Hay-fever

Answer 1

Hint: The most significant characteristics of true bacteria are its unicellular nature, its lack of membrane-bound organelles, and its microscopic size. True bacteria are also known as eubacteria. True bacteria can cause a number of diseases. Yellow fever is caused by Flavivirus and is transmitted via an infected mosquito. Mountain fever is caused by ticks and is characterized by fever, headache, and rashes. Hay-fever is caused due to allergens such as pollen or dust.

Complete answer:
A bacteria called Yersinia pestis causes plague. This bacterium is found in small mammals and their fleas. Animals generally transmit this disease via their fleas. This being a zoonotic bacterium, the transmission from animals to humans is also possible. Yersinia pestis is a gram-negative bacterium and is non-motile. It is a rod-shaped coccobacillus bacteria without the presence of any spores. It is a facultative anaerobic organism which means they have the ability to grow both in the presence and absence of oxygen. It has the ability to infect humans via the Oriental rat flea.
It is the main causative agent of the plague. Pneumonic, septicemic, and bubonic are the three main forms. While the bubonic and septicemic forms are generally spread via flea, the pneumonic form is generally spread between people via air droplets. Thus, Yersinia pestis has features like a true bacterium.
Hence, we can conclude that a true bacterial disease is (B) Plague.

Note: Swollen lymph nodes, fever, headache, chills, fatigue, pain areas in the abdomen are some of the symptoms of plague. Plague may also cause diarrhea and vomiting. Nowadays, antibiotics can be easily used to treat plague.