Worldwide, tuberculosis (TB) is the most frequent cause of death due to a single infectious agent. It is caused by organisms of the Mycobacterium tuberculosis complex, including M. tuberculosis, M. bovis and M. africanum. All three of these organisms are capable of causing TB in humans and the disease can take two forms. Pulmonary TB affects the lung and can be transmitted by coughing or sneezing. Non-pulmonary TB is less common than the pulmonary form and can involve any organ or tissue, most commonly bone, lymph nodes, central nervous system, skin and the genito-urinary tract.

Enhanced Tuberculosis Surveillance

Clinicians in Northern Ireland, in line with those in the rest of the United Kingdom, are required to notify all cases of tuberculosis to the Director of Public Health of the Health and Social Services Board (HSSB) of residence. Enhanced surveillance of tuberculosis was established in Northern Ireland in 1992. All notifications are collated into a Northern Ireland dataset which is validated using laboratory reports and anti-microbial resistance information. The information is then used for inclusion in national and European reports, as well as for disease surveillance at a local level. An annual report is prepared for the Regional Tuberculosis Sub-Committee and circulated to microbiologists, chest physicians and those with an interest in tuberculosis.

Case definitions are based on the recommendations developed by the working group of the World Health Organisation (WHO) and the European Region of the International Union Against Tuberculosis and Lung Disease (IUATLD).

• culture confirmed case is defined as one in which the diagnosis has been confirmed by culture of Mycobacterium tuberculosis, M. bovis or M. africanum .
• non culture confirmed case is based on a clinical diagnosis of tuberculosis, where the physician has the intention to treat with a full course of anti-tuberculous therapy. Such cases may have been clinically diagnosed and "confirmed" by methods other than culture, e.g., sputum smear or histology.

  Both types of cases should be notified through this surveillance system. Any case which subsequently does not fulfil one of the above case definitions is marked as denotified but remains in the dataset. This would include those with diagnosis other than tuberculosis.

• Multi-drug resistance (MDR) is defined as resistance to at least isoniazid and rifampicin, with or without resistance to other drugs.

Link to HPA Data

Last Updated: 10/07/2008

© Copyright CDSC(NI) 2002