Disease and injuries are expected consequences of disasters, either as direct result of the initial disaster or due to a collapse of the pre-existing public health infrastructure. While relief efforts are primarily directed at treating existing and preventing further disease and injury among victims of the disasters, it is also important to remain aware of the health impact on individuals and organizations providing assistance. The potential immune naïveness of relief workers may predispose them to contracting diseases which are normally not a concern for the local population. If significant numbers of relief workers are affected this can severely impact an organizations ability to provide assistance and may lead to a worsening of the situation. Even a simple surveillance program can provide early warning of potential problems in order to timely implement control measures which will prevent further illness and minimize mission impact.