This feature article, written by members of the UN Operational Satellite Applications (UNOSAT) programme, outlines how satellite technology can improve emergency relief after a natural disaster.

UNOSAT uses satellite data to produce maps and damage reports for nongovernment organisations, intergovernmental agencies and disaster managers in emergency situations. The authors describe how the process works — from receiving a relief agency's phone call to collecting and analysing relevant satellite data.

They argue that satellite data, when combined with ancillary data such as road maps or population distribution, can help aid workers navigate affected areas and provide estimates of the number of people likely to be affected by, for example, floods or landslides.

The authors describe the range of satellite sensors used by UNOSAT, explaining the advantages of different types of data depending on the disaster. For example, radar imagery, which is unaffected by cloud, is particularly useful to monitor flooding, whereas high resolution optical data is better for earthquake damage assessment.

This paper, published in the New England Journal of Medicine, examines how the Internet can help monitor, prevent and control emerging diseases. The authors argue that the emergence of influenza A(H1N1), or 'swine flu', in April 2009 shows the value web-based information holds for early disease monitoring.

Informal internet channels such as blogs, chat rooms and search engine request analyses can help identify outbreaks more quickly, prevent governments suppressing information and facilitate public health responses. Google and Yahoo data searches can be used to generate epidemic curves that show the number of new infections plotted against time, and are comparable to those derived from traditional influenza surveillance methods.

The Internet also connects experts — through wikis and social networks — to quickly disseminate reports and responses. There is also great potential from public information.

The authors give examples of approaches being taken to monitor infectious diseases, including swine flu, and highlight some of the online resources available, including Google Flu Trends, HealthMap and ProMED.