What These Vaccines Protect Your 2-Month-Old Baby Against
Your baby is receiving three important vaccines at the 2-month visit that protect against serious, potentially life-threatening infections that are most dangerous in infants and young children.
Prevnar 13 (Pneumococcal Vaccine)
This vaccine protects against 13 types of pneumococcal bacteria that can cause serious infections in babies 1, 2.
What it prevents:
- Meningitis (infection of the lining around the brain and spinal cord)
- Bloodstream infections (bacteremia/sepsis)
- Pneumonia (serious lung infection)
- Ear infections (though less completely than the serious infections above)
Why it matters: Before this vaccine was introduced, pneumococcal bacteria were a leading cause of serious illness and death in young children. The vaccine has been shown to be 97.4% effective at preventing invasive disease caused by the bacteria types it covers 1. Your baby will receive this vaccine at 2,4,6, and 12-15 months 1.
Pediarix (5-in-1 Combination Vaccine)
This single shot protects against five different diseases 3:
- Diphtheria - A serious throat infection that can block the airway and cause heart and nerve damage
- Tetanus (Lockjaw) - Causes painful muscle spasms and can be fatal
- Pertussis (Whooping Cough) - Causes severe coughing fits that make it hard for babies to breathe, eat, or drink; can be deadly in infants
- Polio - Can cause permanent paralysis
- Hepatitis B - A liver infection that can become chronic and cause liver failure or cancer later in life
Why it matters: This combination vaccine means your baby gets protection from five serious diseases with one shot instead of multiple separate injections. Your baby will receive this at 2,4, and 6 months 3.
Important note: The question mentions rotavirus with Pediarix, but rotavirus is actually a separate oral vaccine (given by mouth, not as a shot) that protects against severe diarrhea and dehydration. It's given at the same visit but is not part of the Pediarix shot itself.
PedvaxHIB (Haemophilus influenzae type b Vaccine)
This vaccine protects against Haemophilus influenzae type b (Hib) bacteria 4.
What it prevents:
- Meningitis (the most common serious Hib infection in children)
- Bloodstream infections
- Pneumonia
- Epiglottitis (severe throat swelling that blocks breathing)
Why it matters: Before this vaccine, Hib was the leading cause of bacterial meningitis in children under 5 years old. Since the vaccine's introduction, Hib disease has decreased by 95% 5. Your baby will receive this vaccine at 2,4, and 12-15 months 4.
Safety and Timing
All three vaccines can be safely given together at the same visit 6, 7. The most common side effects are mild and include:
- Fussiness or irritability
- Mild fever
- Redness or swelling at the injection site
- Decreased appetite
These vaccines are given starting at 2 months because this is when babies begin to lose the antibodies they received from their mother during pregnancy, making them vulnerable to these serious infections.