A total of 100 cases of burn were examined and screened bacteriologically for evidence of infection by surface swab culture, quantitative full thickness punch biopsy culture and blood culture. Gram negative organisms predominates the gram positive ones. Surface swab was found to correlate well with the biopsy as far the identification of causative organism is concerned. However, the latter technique was found to be more valuable as it also gives the critical load (>10(5)CFU/g of tissue) of the organism beyond which metastatic invasion of the organism takes place (p<0.01), thus obviating the repeated need for blood culture in burn patients.