Q.1 Which virus is the most common cause of bronchiolitis in infants?
Adenovirus
Respiratory Syncytial Virus (RSV)
Influenza virus
Parainfluenza virus
Explanation - RSV is the leading cause of bronchiolitis in infants and young children worldwide.
Correct answer is: Respiratory Syncytial Virus (RSV)
Q.2 Koplik spots are pathognomonic for which disease?
Measles
Rubella
Scarlet fever
Chickenpox
Explanation - Koplik spots, small bluish-white spots on the buccal mucosa, are a diagnostic feature of measles.
Correct answer is: Measles
Q.3 Which bacterium is the most common cause of bacterial meningitis in children aged 1 month to 5 years?
Escherichia coli
Listeria monocytogenes
Haemophilus influenzae type b
Streptococcus pneumoniae
Explanation - After widespread Hib vaccination, Streptococcus pneumoniae became the most common cause of bacterial meningitis in young children.
Correct answer is: Streptococcus pneumoniae
Q.4 What is the most common complication of mumps in adolescent males?
Orchitis
Pancreatitis
Meningitis
Otitis media
Explanation - Orchitis is the most frequent complication of mumps in post-pubertal males, potentially leading to infertility.
Correct answer is: Orchitis
Q.5 Which vaccine prevents whooping cough?
MMR
DTaP
BCG
Hib
Explanation - The DTaP vaccine provides protection against diphtheria, tetanus, and pertussis (whooping cough).
Correct answer is: DTaP
Q.6 Hand-foot-mouth disease is most commonly caused by:
Coxsackievirus A16
Poliovirus
Enterovirus 71
Echovirus
Explanation - Coxsackievirus A16 is the most common cause, though Enterovirus 71 can also cause severe outbreaks.
Correct answer is: Coxsackievirus A16
Q.7 Which antibiotic is the first-line treatment for streptococcal pharyngitis in children?
Azithromycin
Amoxicillin
Ceftriaxone
Ciprofloxacin
Explanation - Amoxicillin or penicillin remains the first-line therapy for streptococcal pharyngitis.
Correct answer is: Amoxicillin
Q.8 Roseola infantum is caused by which virus?
Human herpesvirus 6
Epstein-Barr virus
Cytomegalovirus
Parvovirus B19
Explanation - Roseola (exanthem subitum) is typically caused by HHV-6 infection in infants and toddlers.
Correct answer is: Human herpesvirus 6
Q.9 Which feature best differentiates rubella from measles?
Maculopapular rash
Postauricular lymphadenopathy
Koplik spots
Cough and coryza
Explanation - Rubella is often associated with postauricular and occipital lymphadenopathy, unlike measles.
Correct answer is: Postauricular lymphadenopathy
Q.10 Which of the following is NOT a common complication of varicella (chickenpox) in children?
Secondary bacterial skin infection
Cerebellar ataxia
Pneumonia
Liver cirrhosis
Explanation - Liver cirrhosis is unrelated to varicella; common complications include skin infections, pneumonia, and ataxia.
Correct answer is: Liver cirrhosis
Q.11 Which bacteria is most associated with post-streptococcal acute glomerulonephritis?
Group A Streptococcus
Staphylococcus aureus
Klebsiella pneumoniae
Enterococcus faecalis
Explanation - Group A beta-hemolytic Streptococcus is responsible for post-streptococcal glomerulonephritis in children.
Correct answer is: Group A Streptococcus
Q.12 In neonatal sepsis, which organism is the most common cause?
E. coli
Listeria monocytogenes
Group B Streptococcus
Staphylococcus epidermidis
Explanation - Group B Streptococcus is the leading cause of early-onset neonatal sepsis.
Correct answer is: Group B Streptococcus
Q.13 Which disease presents with a 'slapped cheek' rash in children?
Measles
Rubella
Erythema infectiosum
Scarlet fever
Explanation - Erythema infectiosum (fifth disease), caused by Parvovirus B19, presents with a characteristic slapped cheek rash.
Correct answer is: Erythema infectiosum
Q.14 The most common cause of community-acquired pneumonia in children is:
Mycoplasma pneumoniae
Streptococcus pneumoniae
Haemophilus influenzae
Respiratory syncytial virus
Explanation - Streptococcus pneumoniae is the most frequent bacterial cause of community-acquired pneumonia in children.
Correct answer is: Streptococcus pneumoniae
Q.15 A child presents with fever, drooling, and tripod position. Which organism is the likely cause?
Haemophilus influenzae type b
Streptococcus pyogenes
Klebsiella pneumoniae
Corynebacterium diphtheriae
Explanation - This presentation is classic for epiglottitis, most commonly caused by Hib (before vaccination).
Correct answer is: Haemophilus influenzae type b
Q.16 The classic 'strawberry tongue' is seen in which pediatric infection?
Kawasaki disease
Scarlet fever
Measles
Rubella
Explanation - Scarlet fever due to Streptococcus pyogenes presents with strawberry tongue, sandpaper rash, and pharyngitis.
Correct answer is: Scarlet fever
Q.17 What is the most effective prevention method for neonatal tetanus?
Neonatal BCG vaccine
Maternal tetanus immunization
Cord care with antibiotics
Vitamin K prophylaxis
Explanation - Immunizing mothers during pregnancy provides protective antibodies against neonatal tetanus.
Correct answer is: Maternal tetanus immunization
Q.18 What is the first-line antibiotic for typhoid fever in children in endemic regions?
Ciprofloxacin
Chloramphenicol
Azithromycin
Amoxicillin
Explanation - Due to resistance patterns, azithromycin is often first-line for uncomplicated typhoid in children.
Correct answer is: Azithromycin
Q.19 Which pathogen causes whooping cough?
Mycoplasma pneumoniae
Bordetella pertussis
Chlamydia pneumoniae
Haemophilus influenzae
Explanation - Bordetella pertussis causes whooping cough, characterized by paroxysmal cough and inspiratory whoop.
Correct answer is: Bordetella pertussis
Q.20 Which organism is the most common cause of otitis media in children?
Haemophilus influenzae
Moraxella catarrhalis
Streptococcus pneumoniae
Staphylococcus aureus
Explanation - Streptococcus pneumoniae is the leading cause of acute otitis media in children worldwide.
Correct answer is: Streptococcus pneumoniae
Q.21 Which of the following is the first symptom of measles?
Rash
Cough
Conjunctivitis
Fever
Explanation - Fever is typically the first symptom of measles, followed by cough, coryza, conjunctivitis, and rash.
Correct answer is: Fever
Q.22 Which infection can lead to Reye’s syndrome if aspirin is given to children?
Chickenpox
Measles
Rubella
Mumps
Explanation - Aspirin given during varicella or influenza can trigger Reye’s syndrome, a serious condition with liver failure and encephalopathy.
Correct answer is: Chickenpox
Q.23 Which vaccine is contraindicated in immunocompromised children?
Polio (IPV)
MMR
DTaP
Hib
Explanation - Live attenuated vaccines like MMR are contraindicated in immunocompromised patients.
Correct answer is: MMR
Q.24 Which of the following causes diphtheria?
Corynebacterium diphtheriae
Clostridium tetani
Mycobacterium tuberculosis
Streptococcus pyogenes
Explanation - Corynebacterium diphtheriae produces an exotoxin that leads to pseudomembrane formation and systemic effects.
Correct answer is: Corynebacterium diphtheriae