Bacteriology and Entomology Supplementary Exam OmpathStudy

Paper One — Special/Supp Exam Mount Kenya University — School of Medicine — Department of Medical Microbiology Bachelor of Medicine and Bachelor of Surgery (MBChB) Unit Code: MBMM3300 — Unit Title: Bacteriology and Entomology Date: Tue 20th Aug 2024, 8:00 AM — Special/Supp — Time: 3 Hours Section A (Answer all questions — 35 Marks)- Which one of the following mites causes Norwegian scabies? A. Leptotrombidium deliense B. Neotrombicula autumnalis C. Eutrombicula alfreddugesi D. Sarcoptes scabiei E. All of the above Answer: D Explanation: Sarcoptes scabiei is the mite that causes ordinary and "Norwegian" (crusted) scabies — the crusted form occurs in immunocompromised patients who cannot mount a normal itch/immune response, allowing massive mite proliferation. Options A, B, and C are chigger mites that cause trombiculiasis (itchy bites), not scabies. --- Which of the following is ODD one out? A. Glossina fuscipes B. Glossina tachnoides C. Glossina palpalis D. Glossina brevipalpis E. None of the above Answer: D (Glossina brevipalpis) Explanation: Tsetse flies are divided into three species groups: palpalis (riverine), morsitans (savanna), and fusca (forest). Fuscipes, tachnoides, and palpalis all belong to the palpalis group. Brevipalpis belongs to the fusca group, making it the odd one out. --- Which of the following is ODD one out? A. Glossina fuscipes B. Glossina fusca C. Glossina longipennis D. Glossina brevipalpis Answer: A (Glossina fuscipes) Explanation: Fusca, longipennis, and brevipalpis all belong to the fusca group. Fuscipes belongs to the palpalis group, making it the odd one out. --- Which of the following is ODD one out? A. Glossina morsitans B. Glossina tachnoides C. Glossina pallidipes D. Glossina longipalpis E. None of the above Answer: B (Glossina tachnoides) Explanation: Morsitans, pallidipes, and longipalpis all belong to the morsitans group. Tachnoides belongs to the palpalis group, making it the odd one out. Must-know area from Q2–4: Memorize the three Glossina groups as a set (palpalis/riverine, morsitans/savanna, fusca/forest) rather than individual species — this exact "odd one out" format is clearly a favorite question style for this examiner and will very likely repeat. --- Which of the following pathogen is transmitted by Tabanids? A. Borrelia burgdorferi B. Francisella tularensis C. Orientia tsutsugamuchi D. Mansonella ozzardi Answer: B Explanation: Tabanids (horseflies/deerflies) are vectors for Francisella tularensis (tularemia) and Loa loa. Borrelia burgdorferi (Lyme disease) is transmitted by Ixodes ticks; Orientia tsutsugamuchi (scrub typhus) by chigger mites; Mansonella ozzardi by Culicoides midges. --- Which of the following conditions can be caused by members of genus Haematopota? A. Diarrhea B. Anemia C. Impetigo D. Fever E. Diarrhea Answer: B Explanation: Haematopota is a genus of tabanid (horsefly). Their bites are painful and cause significant blood loss with repeated/heavy exposure, contributing to anemia in livestock and occasionally humans. They are also mechanical vectors of some pathogens. --- Which of the following stages is found in a hemimetabolous life cycle? A. Egg B. Larvae C. Pupae D. Nymph E. All of the above Answer: D Explanation: Hemimetabolous insects undergo incomplete metamorphosis: egg → nymph → adult, with no pupal stage. Holometabolous insects undergo complete metamorphosis: egg → larva → pupa → adult. This egg/nymph vs egg/larva/pupa distinction is a recurring exam theme. --- Which of the following diseases is associated with Tabanids? A. Scabies B. Lyme disease C. Chikungunya D. Onyong'nyong E. All of the above Answer: None of the listed options fit cleanly based on standard teaching — flag this one to double check against your lecture notes/slides, since Tabanids are classically linked to tularemia, loiasis, and mechanical anthrax transmission, not the diseases listed here. Explanation: Scabies is caused by a mite (not a Tabanid-transmitted disease); Lyme disease is tick-transmitted; Chikungunya and Onyong'nyong are both mosquito-transmitted (Aedes and Anopheles respectively). This question may have a printing/transcription issue — confirm the intended answer with your course notes. --- Which of the following members of tsetse flies are non-vectors? A. Morsitans B. Fusca C. Palpalis D. Riverine E. Muscina Answer: B (Fusca group) Explanation: The fusca group of tsetse flies rarely feeds on humans and is not epidemiologically significant in disease transmission, unlike the palpalis (riverine, sleeping sickness vector) and morsitans (savanna, sleeping sickness/nagana vector) groups. --- Which of the following members of tsetse flies are the smallest in size? A. Morsitans B. Savanna C. Fusca D. Riverine E. None of the above Answer: D (Riverine/palpalis group) Explanation: The palpalis (riverine) group tsetse flies are generally smaller-bodied compared to the fusca (forest) group, which tend to be the largest. --- Which one of the following is referre