A newly 23-valent pneumococcal polysaccharide vaccine was developed with promising safety and immunogenicity demonstrated in the phase III trial in China. A large scale, double blind, randomized, PNEUMOVAX 23 (Merck & Co., Inc.) controlled phase 3 clinical trial was conducted.

The World Health Organization (WHO) estimated that more than 800 000 children younger than 5 years died from pneumococcal disease in 2000, making it the leading vaccine-preventable cause of death. Pneumococcal polysaccharide vaccines have progressed from 2-valent vaccines to the current 23-valent vaccine, which has been available since the early 1980s. The 23-valent vaccine includes serotypes accounting for 72% to 95% of invasive pneumococcal disease, depending on the geographic area. Many countries have added pneumococcal polysaccharide vaccine to their existing national immunization programs or recommended it for people aged 65 years and older and for individuals aged 2-64 who are at increased risk of pneumococcal disease.

A newly 23-valent pneumococcal polysaccharide vaccine was developed with promising safety and immunogenicity demonstrated in the phase III trial in China. A large scale, double blind, randomized, PNEUMOVAX 23 (Merck & Co., Inc.) controlled phase 3 clinical trial was conducted.

Inclusion Criteria:

• Healthy participants older than 2 years were recruited and enrolled in September or October 2012.
• Participants with axillary temperature less than Celsius 37 degrees
• Not yet having received pneumococcal vaccine and other prevention products within 7 days.

Exclusion Criteria:

• Exclusion criteria were any known primary or secondary immunodeficiency
• Allergy
• Severe cardiovascular disease bleeding disorders
• Receipt of immunoglobulin or blood products within one month and so on.-