Journal of Antimicrobial Chemotherapy (1977) 3 (Suppl. Q , 73-75
Epidemiology of common bacterial infections and current trends in the use of antibiotics
IN AM—National Institute for Health Insurance, Rome, Italy
Although the total drug expenditure borne by the National Institute for Health Insurance (INAM) underwent little change between 1963 and 1973, the consumption of broad spectrum, as compared with narrow spectrum, antibiotics increased considerably. In 1963 broad spectrum antibiotics accounted for 6-6% of total diug expenditure, whereas in 1973 the figure rose to 1303%. The consumption of other antibiotics fell from 8-2% in 1963 to 1-18% in 1973. In absolute terms INAM spent roughly 11 thousand million Lire on broad spectrum antibiotics in 1963, approximately 36 thousand million in 1968 and 80 thousand million in 1974, whereas expenditure on remaining antibiotics was practically halved between 1963 and 1974, moving from 14 thousand million Lire to roughly 7 thousand million (see Table I). Table I. Expenditure incurred by INAM for antibiotics in 1963, 1968 and 1974 (in millions of Lire) 1963
1968
1974
Total expenditure for antibiotics Expenditure for broad spectrum antibiotics Expenditure for other antibiotics
24,835
43,328
87,225
11,075 13,760
36,329 6999
79,981 7243
Population insured
26,327,725
27,322,302
30,399,000
It was felt that this radical change in antibiotic consumption could be related to several possible factors: (1) A change in the bacterial flora responsible for some of the more common infectious diseases, together with an increased incidence of bacterial strains resistant to chemotherapeutic and antibiotic agents. (2) A change in the incidence of the more common bacterial infections. (3) Different attitudes to chemotherapy with wider use of broad spectrum antibiotics. Alterations in the bacterial flora responsible for disease are certainly taking place. A study in 1969, for example, showed a rising incidence of Escherichia coli, Proteus, 73
Downloaded from http://jac.oxfordjournals.org/ at University of Tennessee ? Knoxville Libraries on August 19, 2015
Goffredo Fortunio
74
G. Fortunio
Downloaded from http://jac.oxfordjournals.org/ at University of Tennessee ? Knoxville Libraries on August 19, 2015
enterococci, Pseudomonas, etc., compared with infection due to Staphylococcus aureus, streptococci, pneumococci, etc. Finland (1970) examined the incidence of infections in a Boston hospital between 1935 and 1970. He was able to detect a change in bacterial ecology from the first advent of chemoantibiotic therapy to date. The incidence of enterobacterial bacteraemia changed from 12 to 50% between 1935 and 1965, whereas pneumococcal bacteraemia fell from 33 to 13%, group A streptococcal bacteraemia from 33 to 13% and viridans streptococcal bacteraemia dropped from 14 to 7%. As yet, however, neither this changing bacterial ecology nor the increasing incidence of antibiotic resistant bacteria would seem to justify the complete reversal in the use of broad and narrow spectrum antibiotics. We thus undertook an epidemiological survey of the commoner infectious diseases to ascertain whether the change in prescribing habits reflected a difference in their incidence. The data was derived from the records of the National Institute for Health Insurance. The frequency per head of population, the frequency of hospitalization, and the average duration of illness was analysed for each disease in the years 1963, 1968 and 1974. The diseases which were analysed were: acute and chronic upper respiratory tract infections, acute and chronic tonsillitis/quinsy, pneumonia and bronchopneumonias, acute and chronic bronchitis, gastroenteritis/colitis, cholecystitis/cholangitis, pyelonephritis, cystitis, typhoid and paratyphoid fevers and other Salmonella infections. Overall it was found that a large increase in the frequency of certain respiratory infections had occurred over this time. Home treatment cases of acute and chronic bronchitis had risen from 6884-7 per 100,000 insured subjects in 1963 to 7566 per 100,000 in 1974. Hospital treated cases had risen from 183 to 518 per 100,000. Lobar and bronchopneumonia had, however, decreased in incidence from 623 to 298 per 100,000 in hometreated cases and 293 to 251 per 100,000 in hospital-treated cases. Urinary tract infections also increased over this period. However, their overall incidence was not high. In 1974 there were 900,000 home-treated cases and 200,000 hospitalized cases of respiratory infections as against approximately 40,000 home treated and 35,000 hospitalized cases of urinary tract infections. Salmonella infections showed a slight fall from approximately 10,000 cases in 1963 and 1968 to 7000 in 1974. In the same period there were no statistically significant changes in the epidemiology of other gastro-intestinal infections. The most important changes in the epidemiological pattern were thus found to be essentially among the commoner infections of the respiratory tract due mainly to Gram-positive pathogens, which had increased in prevalence. Summing up this data, it would appear that changing epidemiological trends cannot themselves justify the use of broad spectrum antibiotics as opposed to narrow spectrum ones. It would thus appear that this change in prescription habits is due to the current attitude of physicians to therapeutic practice. This attitude is influenced by the increased consultation rate which accompany free health services and to doctors being unable to investigate patients thoroughly and having to recourse to the use of prophylactic broad spectrum antibiotics for ill-defined feverish cases where they fear infective complications. The practitioner is also eager to apply modern and ever more effective therapies and is often influenced by aggressive and efficient promotion of the pharmaceutical industries. He will tend to make use of newer and more powerful antibacterial agents in all cases of infection, whatever its severity, unless he has a sound pharmacological background and gets continuous and independent updating.
Epidemiology and the use of antibiotics
75
As a consequence of these influences there is spreading utilization of these new broad spectrum agents not only by private practitioners, but also by doctors working in major hospital units. It is difficult to suggest effective means to revise this trend. It is vital that physicians and general practitioners realize the dangerous clinical, epidemiological and social threat which the indiscriminate use of broad spectrum antibiotics may produce in the future. Reference Downloaded from http://jac.oxfordjournals.org/ at University of Tennessee ? Knoxville Libraries on August 19, 2015
Finland, M. Changing ecology of bacterial infections as related to antibacterial therapy. Journal of Infectious Diseases 122: 419-31 (1970).
Epidemiology of common bacterial infections and current trends in the use of antibiotics
IN AM—National Institute for Health Insurance, Rome, Italy
Although the total drug expenditure borne by the National Institute for Health Insurance (INAM) underwent little change between 1963 and 1973, the consumption of broad spectrum, as compared with narrow spectrum, antibiotics increased considerably. In 1963 broad spectrum antibiotics accounted for 6-6% of total diug expenditure, whereas in 1973 the figure rose to 1303%. The consumption of other antibiotics fell from 8-2% in 1963 to 1-18% in 1973. In absolute terms INAM spent roughly 11 thousand million Lire on broad spectrum antibiotics in 1963, approximately 36 thousand million in 1968 and 80 thousand million in 1974, whereas expenditure on remaining antibiotics was practically halved between 1963 and 1974, moving from 14 thousand million Lire to roughly 7 thousand million (see Table I). Table I. Expenditure incurred by INAM for antibiotics in 1963, 1968 and 1974 (in millions of Lire) 1963
1968
1974
Total expenditure for antibiotics Expenditure for broad spectrum antibiotics Expenditure for other antibiotics
24,835
43,328
87,225
11,075 13,760
36,329 6999
79,981 7243
Population insured
26,327,725
27,322,302
30,399,000
It was felt that this radical change in antibiotic consumption could be related to several possible factors: (1) A change in the bacterial flora responsible for some of the more common infectious diseases, together with an increased incidence of bacterial strains resistant to chemotherapeutic and antibiotic agents. (2) A change in the incidence of the more common bacterial infections. (3) Different attitudes to chemotherapy with wider use of broad spectrum antibiotics. Alterations in the bacterial flora responsible for disease are certainly taking place. A study in 1969, for example, showed a rising incidence of Escherichia coli, Proteus, 73
Downloaded from http://jac.oxfordjournals.org/ at University of Tennessee ? Knoxville Libraries on August 19, 2015
Goffredo Fortunio
74
G. Fortunio
Downloaded from http://jac.oxfordjournals.org/ at University of Tennessee ? Knoxville Libraries on August 19, 2015
enterococci, Pseudomonas, etc., compared with infection due to Staphylococcus aureus, streptococci, pneumococci, etc. Finland (1970) examined the incidence of infections in a Boston hospital between 1935 and 1970. He was able to detect a change in bacterial ecology from the first advent of chemoantibiotic therapy to date. The incidence of enterobacterial bacteraemia changed from 12 to 50% between 1935 and 1965, whereas pneumococcal bacteraemia fell from 33 to 13%, group A streptococcal bacteraemia from 33 to 13% and viridans streptococcal bacteraemia dropped from 14 to 7%. As yet, however, neither this changing bacterial ecology nor the increasing incidence of antibiotic resistant bacteria would seem to justify the complete reversal in the use of broad and narrow spectrum antibiotics. We thus undertook an epidemiological survey of the commoner infectious diseases to ascertain whether the change in prescribing habits reflected a difference in their incidence. The data was derived from the records of the National Institute for Health Insurance. The frequency per head of population, the frequency of hospitalization, and the average duration of illness was analysed for each disease in the years 1963, 1968 and 1974. The diseases which were analysed were: acute and chronic upper respiratory tract infections, acute and chronic tonsillitis/quinsy, pneumonia and bronchopneumonias, acute and chronic bronchitis, gastroenteritis/colitis, cholecystitis/cholangitis, pyelonephritis, cystitis, typhoid and paratyphoid fevers and other Salmonella infections. Overall it was found that a large increase in the frequency of certain respiratory infections had occurred over this time. Home treatment cases of acute and chronic bronchitis had risen from 6884-7 per 100,000 insured subjects in 1963 to 7566 per 100,000 in 1974. Hospital treated cases had risen from 183 to 518 per 100,000. Lobar and bronchopneumonia had, however, decreased in incidence from 623 to 298 per 100,000 in hometreated cases and 293 to 251 per 100,000 in hospital-treated cases. Urinary tract infections also increased over this period. However, their overall incidence was not high. In 1974 there were 900,000 home-treated cases and 200,000 hospitalized cases of respiratory infections as against approximately 40,000 home treated and 35,000 hospitalized cases of urinary tract infections. Salmonella infections showed a slight fall from approximately 10,000 cases in 1963 and 1968 to 7000 in 1974. In the same period there were no statistically significant changes in the epidemiology of other gastro-intestinal infections. The most important changes in the epidemiological pattern were thus found to be essentially among the commoner infections of the respiratory tract due mainly to Gram-positive pathogens, which had increased in prevalence. Summing up this data, it would appear that changing epidemiological trends cannot themselves justify the use of broad spectrum antibiotics as opposed to narrow spectrum ones. It would thus appear that this change in prescription habits is due to the current attitude of physicians to therapeutic practice. This attitude is influenced by the increased consultation rate which accompany free health services and to doctors being unable to investigate patients thoroughly and having to recourse to the use of prophylactic broad spectrum antibiotics for ill-defined feverish cases where they fear infective complications. The practitioner is also eager to apply modern and ever more effective therapies and is often influenced by aggressive and efficient promotion of the pharmaceutical industries. He will tend to make use of newer and more powerful antibacterial agents in all cases of infection, whatever its severity, unless he has a sound pharmacological background and gets continuous and independent updating.
Epidemiology and the use of antibiotics
75
As a consequence of these influences there is spreading utilization of these new broad spectrum agents not only by private practitioners, but also by doctors working in major hospital units. It is difficult to suggest effective means to revise this trend. It is vital that physicians and general practitioners realize the dangerous clinical, epidemiological and social threat which the indiscriminate use of broad spectrum antibiotics may produce in the future. Reference Downloaded from http://jac.oxfordjournals.org/ at University of Tennessee ? Knoxville Libraries on August 19, 2015
Finland, M. Changing ecology of bacterial infections as related to antibacterial therapy. Journal of Infectious Diseases 122: 419-31 (1970).
