In 2004, infectious diseases are still the second leading cause of death worldwide, the number of emerging or re-emerging bacterial, fungal and viral pathogens continues to increase, and the threat of bioterrorism looms large worldwide.Thus, the need for new antimicrobial agents is perhaps greater now than it has ever been, and with the lack of new anti-infectives in the pipeline, there is great interest in innovative strategies.

Innate immunity is the first line of defence against pathogens and is initiated rapidly after recognition of microbial products by receptors such as the Toll-like receptors (TLRs). We outline the signalling cascades initiated by TLR triggering and the therapeutic potential of targeting this pathway, as well as relevant Highlight articles from the journal.

An abundant and safe food supply is the minimum expectation from our agricultural industry. Fulfilling this demand is a complex process involving plant cultivation, soil and water management, animal husbandry, harvesting, processing, storage and transport. The impact of microorganisms permeate every stage of this process — both positively and negatively — and understanding their role will be crucial to sustaining and improving food production, quality and safety. In this series of articles, Nature Reviews Microbiologyexplores the latest developments in the field of food microbiology.

Infectious diseases kill more than 14 million people each year, 90% of whom live in the developing world. In this series of articles we focus on the biology of infectious diseases that disproportionally affect poor and marginalized populations. This series will also examine the strategies being developed to contain and, ultimately, eradicate these diseases. The 'Tropical Infectious Disease' article series has been developed in collaboration with the WHO/TDR.

When antibiotics were first introduced into widespread clinical use in the 1950s, it was generally believed that bacterial diseases No. longer constituted a public health threat. With the emergence of new infectious diseases, the re-emergence of old diseases, and the rise of antibiotic resistance, this early optimism has long since eroded. In this series of articles, we explore important issues relevant to the development and use of anti-infectives, including discussions on new approaches to regain the upper hand over infectious diseases.

This collection, along with other analysis of key components of the ocean's food web, highlights the significance of genome sequences from the sea. We powerfully demonstrate how genomics can lead to a new understanding of biodiversity, ecology and biogeochemistry.

In March 2003, the World Health Organization issued global warnings about a mysterious and deadly form of pneumonia. Our reporters pose key questions about the outbreak, and assess our preparedness to deal with future viral threats.

This focus provides a broad picture of the importance of microbial genetics but, more than this, they show that the answers to the big questions that were provided by this field in the past might be the tip of an iceberg that looms large in the future.

The term 'weapons of mass destruction' seems destined to be one of those rare pieces of jargon that insinuates itself into common usage. The reason for this dubious honour is, of course, that the deployment of such weapons, particularly agents of bioterror, has rarely seemed as possible as it does today. For the same reason, the question of biodefence - defence against agents of bioterror - is high on the agendas of governments, the public and the research community.

Each year an estimated 8 million people develop clinical disease and 1.87 million people die of TB. These staggering numbers make tuberculosis one of the leading infectious disease killers. Although complete eradication of TB once seemed possible, the increasing incidence of multidrug resistant (MDR) strains, and the deathly specter of AIDS which increases the risk of developing TB 30-fold, means that we are now faced with reemergence of the disease as a global health emergency

Around 400 million people now suffer from the disease, with 130 million new cases occurring annually. The genome of the Anophelesmosquito has been mapped and is now being sequenced, and the complete genome sequence ofP.falciparumshould be at hand within the next year.