Epidemiological aspects of outbreaks of food-borne salmonellosis in Scotland between 1980 and 1989.

Between 1980 and 1989, 2,212 outbreaks of food-borne infection were reported in Scotland. Of 2,073 episodes for which a causative agent was established, 1,732 (84%) were caused by salmonellae. An average of 980 people were affected each year, while the average number of individuals infected per general outbreak was 16.8. The infected foods were consumed outside Scotland in 25% of the outbreaks. In 75% of 1,107 episodes where the location was specified, the implicated foods were consumed in the home; hotels and restaurants accounted for 15%. Specific food items were identified in 603 (35%) of the 1,732 outbreaks; poultry meat was responsible for 332 (55%) and milk 49 (8%), while eggs accounted for 23 (4%) outbreaks.

Lochgoilhead fever: outbreak of non-pneumonic legionellosis due to Legionella micdadei.

Analysis of case histories from 187 people who had visited a hotel and leisure complex in Lochgoilhead, a village on the west coast of Scotland, indicated that 170 had had an acute illness characterised by headache, fatigue, arthralgia, myalgia, cough, and breathlessness. These symptoms were consistent with Pontiac fever-like illness. Legionella micdadei was isolated from the leisure complex whirlpool spa at the time that 60 of 72 individuals with symptoms seroconverted to L micdadei antigen. This outbreak is thought to be the first of a Pontiac fever-like illness ascribed to L micdadei and the first large-scale outbreak of its kind to have occurred outside North America. Whirlpool spas can be a major reservoir of legionella organisms; they must therefore be properly maintained and operated to prevent outbreaks of infection.

Food poisoning in hospitals in Scotland, 1978-87.

During the 10-year period 1978-87 there were 48 outbreaks of food poisoning in Scottish hospitals affecting a total of 2287 persons of whom 12 died. This compared with 50 outbreaks during the previous 5 years (1973-77) when over 1500 persons and 7 deaths were recorded. Although the incidence of outbreaks has decreased the average number of persons affected in outbreaks has increased. A marked reduction was seen in the incidence of outbreaks due to Clostridium perfringens, in contrast to foodborne salmonellosis which remains a problem. Thirty-four hospitals, of which 10 reported two or more outbreaks, were involved. The type of hospitals most frequently affected were general (14), psychiatric (13), geriatric (9) and hospitals for the mentally subnormal (7). Meat, including poultry meat, was incriminated in over 90% of outbreaks where a food vehicle was identified. In modern or re-equipped kitchens cooking in advance with subsequent reheating is being progressively discontinued as more food is being cooked on the day of consumption, a practice which may readily explain the decreasing incidence of outbreaks due to Cl. perfringens. Bacterial cross-contamination from poultry-meat and other raw foods, compounded by inadequate temperature control, however, continues to be a problem in some hospitals. It is too early as yet to determine whether the removal of Crown immunity will have any effect on the future incidence of hospital 'food poisoning'.

Poultry-borne salmonellosis in Scotland.

Between 1980-5, 224 outbreaks of salmonellosis associated with poultry-meat were reported in Scotland. In total 2245 persons were affected, 12 of whom died. Twenty-one salmonella serotypes were identified from those affected, while 33 serotypes were isolated from poultry during routine monitoring and disease investigation. Existing measures to prevent the spread of salmonellae within poultry flocks and processing plants are failing. It is suggested that irradiation of poultry-meat may be the only effective method of reducing the public health problem of poultry-borne salmonellosis.

Surveillance programme for the control of foodborne infections and intoxications in Europe: the first 6 years' experience in Scotland, 1980-85.

In 1979 WHO recommended the establishment of a surveillance programme in Europe for foodborne infections and intoxications that incorporated an early warning system for incidents affecting more than one country as well as a routine reporting system to record details of outbreaks of foodborne disease. The Early Warning System was introduced in Scotland in July 1979 and the Routine Reporting System in January 1980. By the end of 1985, 23 European countries were participating in the programme.The introduction of the surveillance programme in Scotland permitted the formation of a standard national reporting system for foodborne infections and intoxications. During the 6 years from 1980 to 1985, the major features of the programme in Scotland have been the introduction of compulsory pasteurization of cows' milk, in 1983, with the consequent eradication of general outbreaks of milkborne salmonellosis; the emergence of poultry meat as the major food vehicle of infections; and the development of techniques for costing foodborne disease outbreaks.

Surveillance programme for the control of foodborne infections and intoxications in Europe: The first 6 years' experience in Scotland, 1980-85

In 1979 WHO recommended the establishment of a surveillance programme in Europe for foodborne infections and intoxications that incorporated an early waning system for incidents affecting more that one country as well as a routine reporting system to record details of outbreaks of foodborned disease. The Early Warning System was introduced in Scotland in July 1979 and the Routine Reporting System in January 1980. By the end of 1985, 23 European countries were participating in the programme. The introduction of the surveillance programme in Scotland permitted the formation of a standard national reporting system for foodborne infections and intoxications. During the 6 years from 1980 to 1985, the major features of the programme in Scotland have been the introduction of compulsory pasteurization of cow's milk, in 1983, with the consequent eradication of general outbreaks of milkborne salmonellosis; the emergence of poultry meat as the major food vehicle of infections; and the development of techniques for costing foodborne disease outbreaks

Susceptibility of itinerants ("travelling people") in Scotland to poliomyelitis.

A total of 109 travelling people (people with a nomadic lifestyle), living on 8 separate sites in central and south Scotland, were examined for neutralizing antibodies to poliovirus types 1, 2, and 3. Of those studied, 10% had no detectable antibody to poliovirus type 3 while 7% had no antibody to type 1, the types most commonly associated with outbreaks of paralytic poliomyelitis. Only one subject, a child aged 9 years, had no detectable poliomyelitis antibody; he had no history of poliomyelitis immunization. The best protected groups of travellers were those located on sites with good facilities.As far as poliomyelitis is concerned, we conclude that travelling people in Scotland who live on well equipped sites do not pose a hazard to nearby settled populations and, indeed, are no more vulnerable to infection than members of those communities.

Interprofessional liaison in Scotland.

Communication between the medical, veterinary and environmental health professions has been established in Scotland since the early 1970s and was strengthened by the introduction of the Zoonoses Order 1975. The secondment of a veterinary officer to the Communicable Diseases (Scotland) Unit in Glasgow provides veterinary expertise on matters relating to public health, in addition to improving liaison, surveillance and the other functions of the unit.

Food poisoning in hospitals in Scotland.

A review of 50 hospital-based outbreaks of food poisoning which were reported in Scotland during 1973--7, is described. At least 1530 persons consuming hospital-prepared food were involved. Thirty-one episodes were associated with Clostridium perfringens (C. welchii), 11 were due to food-borne salmonella infection, three to enterotoxigenic Staphylococcus aureus, and five incidents were of undetermined aetiology. This differs noticeably from the experience in England and Wales where salmonellas appear to predominate as the main cause of hospital outbreaks. Twenty-two incidents occurred in hospitals for psychiatric or mentally subnormal patients, and ten others were located in geriatric units. Only 33 hospitals were involved in the 50 outbreaks as nine hospitals experienced two or more episodes. The role of the hospital in the occurrence of food poisoning may be over-emphasized in comparison with other catering establishments, as outbreaks are more readily recognized and laboratory facilities are usually available for investigation, but it is also believed that many episodes may not be reported. The peculiar problems of the hospital-catering service and particularly those of the older long-stay hospitals, are discussed in relation to preventive measures which would minimize the hazards of food poisoning.