7-Valent pneumococcal conjugate vaccine and lower respiratory tract infections: Effectiveness of a 2-dose versus 3-dose primary series

Our findings suggest that a 2-dose PCV7 primary series, while conferring savings from reduced vaccine costs in comparison with a 3-dose primary series, also may confer less protection against LRTD in the first year of life, at least during the period soon after the vaccine is introduced.