Nasopharyngeal pneumococcal colonization density is associated with severe pneumonia in young children in the Lao People’s Democratic Republic by Carr, OJJ, Vilivong, K, Bounvilay, L, Dunne, EM, Lai, JYR, Chan, J, Vongsakid, M, Chanthongthip, A, Siladeth, C, Ortika, B, Nguyen, C, Mayxay, M, Newton, PN, Mulholland, K, Do, LAH, Dubot-Pérès, A, Satzke, C, Dance, DAB, Russell, FM