On 27 November 2007 these pages were updated to include confirmed notifications of infectious diseases to the year ended 31 December 2006. A summary of key points was simultaneously released as a formal Statistical Publication Notice.

Background

The information presented in this section is derived from data on notifiable infectious diseases that have been returned to ISD Scotland by NHS Boards under the terms of statutory public health legislation.  Notifiable infectious diseases include mumps, measles, rubella, tuberculosis and food poisoning. 

Notifications are made upon diagnosis and, as such, are a clinical suspicion of an infection.  They do not necessarily indicate the presence of the disease itself.  GPs are encouraged to seek laboratory confirmation of infection where possible.  The number of notifications, therefore, can differ from the number of laboratory confirmed cases.

Data Collection

Described below is the process that was followed by ISD to collect data on notifiable infectious diseases up to June 2007.  Note that responsibility for the collection and future publication of this data was transferred to NHS Health Protection Scotland (HPS) in June 2007.  HPS is responsible for the national surveillance of communicable diseases and co-ordination of national protection activity.

Notifications of infectious diseases are recorded on three aggregate datasets:

• provisional weekly notifications are collected on form ISD(D)2
• confirmed  annual notifications are collected on form ISD(D)3 (which excludes tuberculosis)
• confirmed  annual tuberculosis notifications are collected on form ISD(D)6

The weekly figures, although classified as provisional and subject to revision, allow regular monitoring of infection and provide up-to-date information on outbreaks.

The annual figures are based on confirmed  notifications, including any revisions to provisional diagnoses, and offer the opportunity to study longer time series.

Notifications data complement other ascertainment sources, such as laboratory confirmation, of communicable diseases cases. However, they should be treated with caution and interpreted with respect to these other sources.

Provisional notifications and more detailed information, including data on laboratory reports, are published by Health Protection Scotland (HPS)  in its Weekly Report and in scientific journals.

The 2006 update section contains a summary of key points and detailed tables and charts of notifiable infectious diseases data.

Terminology These data use the term confirmed in a particular way. NHS Boards submit numbers of notifications on a weekly, provisional basis and revise their submissions in an annual summary, usually in the spring of each year. These revised figures are described as confirmed notifications but do not necessarily indicate the presence of the infection itself.  True confirmation of infection can be made by laboratory investigation and whether this has taken place is not recorded on forms ISD(D)3 & 6. Thus, confirmed notifications remain a clinical suspicion of infection and counts may differ from those of laboratory confirmed cases. For example, salivary surveillance schemes exist for measles, mumps and rubella. In a paper published by the Scottish Centre for Infection and Environmental Health (SCIEH), the incidence of these diseases in 2002 was low compared to the numbers of notifications submitted. Under 1% of measles notifications showed evidence of recent infection; for mumps, 21% of notifications followed through by laboratory test showed evidence of recent infection; none of the laboratory tests for rubella showed evidence of recent infection. Reference:  Bramley, Claire. Enhanced salivary surveillance for measles, mumps and rubella, Scotland, 2002. SCIEH Weekly Report 26 August 2003, vol. 37, no. 2003/34