Miscellaneous Bacteria - Yersinia, Brucella, Bartonella, Legionella MCQs

Quintana: It is transmitted by louse. It is the agent of - Trench fever: It occurred as epidemics in the trenches during World War I. It is a mild febrile illness which lasts for five days, subsequent episodes occurring every 5 days (hence also called as 5 days fever). Thereafter, it was found to be silent for decades. However, the disease has re-emerged in USA recently. Reference : Essentials of Medical Microbiology, by Apurba Sastry and Sandhya Bhat, 3rd edition, page no: 315

Isolation of F.tularensis is very difficult as it is highly fastidious. It needs Special media, such as: BCG agar (blood cysteine blood agar) CHAB agar (cysteine heart agar supplemented with 9% heated sheep blood). Reference : Essentials of Medical Microbiology, by Apurba Sastry and Sandhya Bhat, 3rd edition, page no: 808

Tularemia, also known as “rabbit fever,” is a disease caused by the bacterium Francisella tularensis. Tularemia is typically found in animals, especially rodents, rabbits, and hares. Gentamicin is considered as the drug of choice,given 5mg/kg for 7-10 days. Doxycycline or ciprofloxacin can be given as alternatives. Reference : Essentials of Medical Microbiology, by Apurba Sastry and Sandhya Bhat, 3rd edition, page no: 810

Tularensis has four subspecies: tularensis, holarctica, novicida, and mediasiatica. The first three subspecies are found in North America, whereas subspecies mediasiatica is found in central Asia. Subspecies tularensis is the most common and the most virulent among all. Reference : Essentials of Medical Microbiology, by Apurba Sastry and Sandhya Bhat, 3rd edition, page no: 808

Ans. is d i.e., Lipids Proteins are most immunogenic, while lipids & nucleic acids are least immunogenic. Polysaccharides (carbohydrates) are less immunogenic than protein antigens, but are more antigenic than lipids & nucleic acids. 667. The correct order of gram staining is a) Gentian violet → Iodine → Carbol fuchsin b) Iodine → Gentian violet → Carbol fuchsin c) Carbol fuchsin → Iodine → Gentian violet d) Carbol fuchsin → Gentian violet → Iodine Correct Answer - A Answer-A- Gentian violet → Iodine → Carbol fuchsin

B.melitensis is the most pathogenic species, followed by B. abortus and B. suis. Human infection with other species is extremely rare. Transmission: Brucellosis is zoonotic, transmitted from infected animals to man by various modes: Direct contact: The most common route is direct contact of abraded skin or mucosa with the infected animal tissue, blood, urine, vaginal discharge or placenta Food-borne: By ingestion of unpasteurized milk or dairy products or undercooked meat from infected animals or rarely vegetables or water contaminated with animal excreta Air-borne: By inhalation of dust or aerosols in the infected cowshed or slaughterhouses Person-to-person spread is extremely rare; through breast milk or by tissue transplantation or blood transfusions. Reference : Essentials of Medical Microbiology, by Apurba Sastry and Sandhya Bhat, 3rd edition, page no: 316

Brucellosis is diagnosed in animals by various methods such as: Milk ring test and Rose Bengal card test; detecting antibodies in infected milk. Reference : Essentials of Medical Microbiology, by Apurba Sastry and Sandhya Bhat, 3rd edition, page no: 318

Various regimens are recommended for the treatment of brucellosis. Standard regimen in adults: Gentamicin for 7 days plus doxycycline for 6 weeks. Streptomycin can be given alternative to gentamicin. WHO regimen in adults: Rifampicin for 6 weeks plus doxycycline for 6 weeks Relapse or treatment failure occurs in 5–10% of cases. For CNS involvement: Ceftriaxone is added to the regimen and treatment is prolonged for 3–6 months. Reference : Essentials of Medical Microbiology, by Apurba Sastry and Sandhya Bhat, 3rd edition, page no: 319