Millions of vaccine doses are wasted each year due to a lapse in recommended storage conditions. Maintaining the cold chain for vaccines is both expensive and difficult, especially in developing countries. The present study investigated the safety and immunogenicity of a single dose of the conjugated meningococcal Group C vaccine, Menjugate, stored for 6 months at room temperature (25+/-2 degrees C, N=250) or at 2-8 degrees C (N=250) when administered to 12-23 months toddlers. In the two respective groups, 87 and 88% of toddlers reached bactericidal antibodies titers of at least 1:8. The immunogenicity of Menjugate stored at room temperature was not inferior to that stored at 2-8 degrees C. The safety profile and immunogenicity of the vaccine was not influenced by the storage condition.