Correspondence South-Asian tsunami "Chance favours the prepared mind." Louis Pasteur (1822-95) We agree with your proposal for an International Commission on Global Responses to Complex Emergencies to plan and coordinate evidence-based emergency responses (Jan 8, p 95).1 Communicable diseases such as cholera, dysentery, malaria, and dengue can be expected after crises like the tsunami of Dec 26, 2004, which destroyed much of the public-health infrastructure in the affected areas.2 Malnourishment can also increase sus- ceptibility to infections such as tubercu- losis.3 Furthermore, not all relief workers may have received the necessary vacci- nation or chemoprophylaxis. A microbi- ology laboratory thus has an important role in detecting these infectious pathogens, and in triggering appropri- ate disease control responses. We set up a field microbiology laboratory in the week following the southeast Asian tsunami in the northern province of Sumatra, Indonesia. Our ability to establish a field labora- tory reflected our preparedness to deal with outbreaks of infectious diseases in modern Singapore, not in a disaster area. Diseases such as cholera are rare in Singapore. With the exception of dengue, procurement of simple and rapid diagnostic assays for the pathogens of concern, particularly in lateral-flow chromatography format, was slow owing to the limited supplies in stock within Singapore. Most such tests had to be purchased from abroad. Hence, our field laboratory had to start off with a small number of simple, rapid tests supplemented with real-time polymerase chain reaction (PCR) assays for diseases such as malaria.4 We were able to deploy these tests rapidly, given our role as the national laboratories for Singapore. Although some may argue that real- time PCR with a Lightcycler (Roche Diagnostics, Mannheim, Germany) is costly and its performance in a hot and humid field laboratory untested, it does offer advantages over conventional microbiological assays. Minimal han- dling of clinical specimens is required and pathogens are inactivated through nucleic acid extraction, thereby reduc- ing the risk of laboratory-acquired infec- tion. The amount of biohazardous waste generated is also less than with culture-based methods. We will be assessing how well real-time PCR per- forms in our field laboratory, and hope that our findings provide data on its usefulness for future emergency opera- tions. Apart from rapid diagnosis, microbi- ology laboratories can also help in re- establishment of the public-health infrastructure. Seroepidemiological studies could determine the levels of herd immunity to various diseases, which could be critical, particularly if local epidemiological records are destroyed. Public-health programmes could thus be rebuilt on the basis of real, rather than perceived, needs. A coordi- nated response between primary-care physicians and nurses, epidemiologists, and microbiologists would be essential for the success of such studies. Perhaps an international commission could heed Louis Pasteur's observation, and prepare and coordinate future efforts so that the people who suffer natural disasters have a favourable chance of overcoming outbreaks of infectious disease that follow their heels. We declare that we have no conflict of interest. We thank our many colleagues who aided, in one way or another, the setting