Haemophilus is part of the Bacteriology section of Microbiology. Practise 24 exam-style MCQs for NEET PG, FMGE, INI-CET and NEET SS, each with the correct answer and a detailed explanation.
Haemophilus MCQs explore acellular pertussis vaccine components, pertussis toxin raising cAMP, hemin and NAD as growth factors X and V, and Bordet–Gengou agar for whooping cough — high-yield NEET PG revision.
Sample Haemophilus MCQs with answers
Sample MCQ #1
Acellular pertussis vaccine is composed of: a) Pertussis toxoid b) FHA c) Pertactin d) IgA e) Adhesins f) cAMP
Aa,b,c
Ba,b,c,d
Ca,e,d,f
Da,b,c,d,e,f
Show Answer & Explanation ▾
✓ Correct Answer: A. a,b,c
Acellular Pertussis Vaccine: It is composed of pertussis toxoid and 2 or more other bacterial components such as FHA, pertactin or fimbriae. Though the efficacy is same as the WC vaccine, it is associated with fewer side effects as compared with the latter and can be safely given after 5–6 years. It is available as DaPT (along with diphtheria and tetanus toxoid). It is recommended for older children who have missed their primary doses of DPT. Reference : Essentials of Medical Microbiology, by Apurba Sastry and Sandhya Bhat, 3rd edition, page no: 641
Sample MCQ #2
What is the mechanism of toxin produced by Bordetella Pertussis?
AInhibition of EF2
BInhibition of EF1
CIncrease cAMP
DIncrease cGMP
Show Answer & Explanation ▾
✓ Correct Answer: C. Increase cAMP
Mechanism of various bacteria toxins: Inhibition of elongation factor 2: Diphtheria toxin Pseudomonas Increase cAMP: Remember: 'CAEP' Cholera Anthrax ETEC labile toxin Pertussis Increase cGMP: ETEC stable toxin Reference : Essentials of Medical Microbiology, by Apurba Sastry and Sandhya Bhat, 3rd edition, page no: 638
Sample MCQ #3
Which of the following special factors are required for Haemophilus? A. Hemin B. Christmas factor C. Nicotinamide adenine dinucleotide D. Fibrinogen E. Thrombin F. Ca2+ G. Fe2+
Aa, b, c, f
Ba, c
Cb, c
De, f, g
Show Answer & Explanation ▾
✓ Correct Answer: B. a, c
Haemophilus requires two accessory growth factors (factor X and V) in blood for their growth. Factor X is a hemin, present freely in blood. Factor V is nicotinamide adenine dinucleotide (NAD), which is present inside RBCs. It is also produced by some bacteria, such as Staphylococcus aureus. Growth surrounding X and XV disks only: Produced by species that require X factor, but not V factor; examples include H. ducreyi and A. aphrophilus. Growth surrounding V and XV disks only: Produced by species that require X factor, but not V factor; examples include H. parainfluenzae, H. parahaemolyticus and A. paraphrophilus. Growth surrounding combined XV disk only: Produced by species that require both X and V factors; examples include: H. influenzae, H. aegyptius and H. haemolyticus. Reference : Essentials of Medical Microbiology, by Apurba Sastry and Sandhya Bhat, 3rd edition, page no: 612
Sample MCQ #4
Which growth factor is essential for the growth of Haemophilus influenzae in culture media?
AVitamin B12
BHemin (Factor X)
CFolic acid
DSodium chloride
Show Answer & Explanation ▾
✓ Correct Answer: B. Hemin (Factor X)
Hemin (Factor X): Correct - Haemophilus influenzae specifically requires hemin (Factor X) for growth, which must be supplied in enriched culture media, as it cannot synthesize it. Why Not Others : Vitamin B12: Incorrect - While important for many bacteria, it is not necessary for the growth of Haemophilus influenzae . Folic acid: Incorrect - Although it may be involved in metabolic processes, it is not the primary growth factor required by Haemophilus influenza . Sodium chloride: Incorrect - Sodium chloride is used for osmotic balance but is not a specific growth factor for Haemophilus influenzae . Key Takeaway: Hemin (Factor X) is crucial for the growth of Haemophilus influenzae in culture media, as this organism cannot synthesize it. Tags: good to know Tag Line: EASY Reference: Shastri, A. (2021). Essentials of Medical Microbiology (3rd ed.). Publisher, Chapter 61, pp 610.
Sample MCQ #5
A 3 year old boy came to Pediatric OPD with complaints of low-grade fever, cough and vomiting. His vitals are normal and growth is appropriate for his age. On examination, the boy coughs for 10 times in a row with a typical sound at the end. His parents do not believe in getting him vaccinated stating that vaccines are for weak people and their son is the strongest person. Which of the following media is used to isolate the given bacteria? i. PPLO agar ii. Bordet-Gengou agar iii. PLET media iv. Regan Lowe media v. Pike's media
Ai, ii, iii, iv, v
Bi, iii, v
Cii, iv
Dii, iii, iv
Show Answer & Explanation ▾
✓ Correct Answer: C. ii, iv
Following scenario most likely suggests Bordetella Pertussis infection. B. pertussis causes Whooping Cough/100 days fever. Clinical course is divided into 3 stages. Catarrhal phase: 1-2 weeks // cough, coryza, lacrimation, low-grade fever // highly infectious stage // smear and culture +ve Paroxysmal phase: smear and culture -ve // whooping cough and post-tussive vomiting Convalescent phase: recovery phase Vaccination status has increased. Now usually seen in unvaccinated kids. -Lab techniques: Gram staining shows gram-negative coccobacilli (thumbprint appearance) Boredet-Gengou/ Regan Lowe media- shows bisected pearl or mercury drop appearance Other Options: PPLO agar- used for Mycoplasma PLET media- used for Bacillus anthrax Pike's media- Transport media for Streptococci Reference : Essentials of Medical Microbiology, by Apurba Sastry and Sandhya Bhat, 3rd edition, page 593
Sample MCQ #6
A 3-year old boy came to Pediatrics OPD with complaints of low-grade fever, cough and vomiting. His vitals are normal and growth is appropriate for his age. On examination, the boy coughs for 10 times in a row with a typical sound at the end. His parents do not believe in getting him vaccinated stating that vaccines are for weak people and their son is the strongest person. Which of the following media is used to isolate the given bacteria? i. PPLO agar ii. Bordet-Gengou agar iii. PLET media iv. Regan Lowe media v. Pike's media
Ai,ii,iii,iv,v
Bi,iii,v
Cii,iv
Dii,iii,iv
Show Answer & Explanation ▾
✓ Correct Answer: C. ii,iv
Following scenario most likely suggests Bordetella Pertussis infection. Pertussis causes Whooping Cough/100 days fever. Clinical course is divided into 3 stages. Catarrhal phase: 1-2 weeks // cough, coryza, lacrimation, low-grade fever // highly infectious stage // smear and culture +ve Paroxysmal phase: smear and culture -ve // whooping cough and post-tussive vomiting Convalescent phase: recovery phase Vaccination status has increased. Now usually seen in unvaccinated kids. Lab techniques: Gram staining shows gram-negative coccobacilli (thumbprint appearance) Bordet-Gengou/ Regan Lowe media- shows bisected pearl or mercury drop appearance Other Options: PPLO agar- used for Mycoplasma PLET media- used for Bacillus anthrax Pike’s media- Transport media for Streptococci Reference : Essentials of Medical Microbiology, by Apurba Sastry and Sandhya Bhat, 3rd edition, page no: 640
What you can practise in Haemophilus
24 Haemophilus MCQs on Bacteriology — each with detailed explanations
Previous-year question practice across NEET PG, FMGE, INI-CET and NEET SS
Progress and performance tracking to measure retention
Haemophilus MCQs explore acellular pertussis vaccine components, pertussis toxin raising cAMP, hemin and NAD as growth factors X and V, and Bordet–Gengou agar for whooping cough — high-yield NEET PG revision.
How many Haemophilus questions are there, and which exams do they cover?
MedLadder includes 24 curated MCQs for Haemophilus under Microbiology (Bacteriology), covering NEET PG, FMGE, INI-CET and NEET SS preparation.
