Each disease is classified into disease category, type of agent, and acuity (acute-severe, acute-moderate, or subacute). For each disease, the application shows initial symptoms, latency or incubation period, signs and symptoms, and any activities associated with increasing the risk of disease. Some of these activities are occupational, and the database contains 103 jobs that are linked to high-risk occupational activities, e.g., farmers exposed to infected animals. Also shown are all major outbreak syndromes, e.g., "rash and fever," and the diseases included in each syndrome. For infectious diseases, the application shows where the disease occurs in the world, how it is diagnosed in the laboratory, it source from patients, water, soil, and animal excreta or tissue, its route of entry into the body by inhalation, ingestion, or skin; and the insect vectors and animal reservoirs.

OutbreakID covers 156 infectious diseases--either distinct diseases or groups of diseases. For example, "Viral encephalitides, mosquito-borne" is one of the groups covered. For the most part, OutbreakID does not cover infections that are limited to post-surgical or immunosuppressed patients. The focus is on the early detection of infections that could cause outbreaks in healthy people. OutbreakID covers nearly every infectious disease listed in the Control of Communicable Diseases Manual. Some infections in that book are not included in OutbreakID: actinomycosis, aspergillosis, candidiasis, dermatophytosis, dirofilariasis, malignant neoplasms associated with infectious agents, molluscum contagiosum, mycetoma, nocardiasis, pediculosis, phthiriasis, scabies, viral warts, and zygomycosis.

Having information organized into a relational database means that the user can find diseases by means of queries. For example, the user can query the database of 201 diseases to find all that match a certain criteria:

	A syndrome, e.g., "Fever and rash," or "Jaundice and fever," or "Acute neurological, no fever";
	A sign or symptom, e.g., cough, paralysis, bradycardia, leukopenia, petechiae, or pleural effusion;
	An activity, e.g., traveled to China, bitten by a tick, drank unpasteurized milk, or took care of a sick bird; or
	A job, e.g., farmer, nurse, or groundskeeper.

The user can also perform "AND" searches, for example, all the diseases that match:

	Travel to central Africa AND bleeding tendency plus fever;
	Cat contact AND diarrhea;
	Tick exposure AND decreased platelets; or
	Working as a veterinarian AND encephalitis.

A disease that is not considered is not diagnosed. In this time of globalization and bioterrorism, it is imperative to consider all the diseases in the world. Information about these diseases exists in journals of emerging infectious disease and textbooks of tropical, military, and occupational medicine. It is time to collect all of this information, classify it, index it, and store it in one computer database for easy access. By providing quick access to facts about outbreaks, OutbreakID could help medical and public health professionals to participate in a surveillance system for the early detection of outbreaks.