The ESAC project established for the first time a credible alternative to industry sources for the collection of internationally comparable data on antibiotic use in Europe, based on cooperation between regulatory authorities, scientific societies, health insurers and professional organizations. These data provide a tool for assessing public health strategies aiming to optimize antibiotic prescribing.

Allopurinol monotherapy has no effect on Colombian cutaneous disease primarily caused by L. panamensis and therefore is unlikely to be effective against cutaneous leishmaniasis in other endemic regions.

There has been a substantial change in the use pattern of quinolones between 1997 and 2003, since the introduction of quinolones that are effective for the treatment of respiratory tract infections. These quinolones are not the first-line antibiotics for this indication and therefore quinolone use should in general still be limited and not show substantial seasonal variation.

Leishmaniasis in Colombia has traditionally been seen as a health risk for adult males, as they become infected when they enter the vector

In all 20 European countries studied together, 2.04% of outpatient antibiotics were used for parenteral treatment. However, as for the total outpatient antibiotic use and the use of different antibiotic groups and antibiotics, there is a striking variation in the proportions of parenteral antibiotic use in Europe. More in-depth data on outpatient antibiotic use are needed to explain this variation.

The observed differences between European countries in the levels of MLS use and the extreme seasonal variations in their use suggest that this class of antibiotics is prescribed inappropriately in many countries. The MLS classification developed here facilitates a more comprehensive description of macrolide use in Europe. These data (collected as part of ESAC) could promote investigations that lead to a deeper understanding of the link between macrolide use and resistance.

Penicillins represent the most widely used antibiotic class in all 25 participating countries; albeit with considerable variation of their use patterns. A distinct shift from narrow-spectrum penicillins to broad-spectrum penicillins, and specifically their combinations with beta-lactamase inhibitors, was observed during the period 1997-2003.

The new ATC codes allow a more detailed description of outpatient cephalosporin use. The variation in antibiotic use in Europe is most extreme for this class of antibiotics, suggesting that in many countries in Europe these antibiotics are prescribed inappropriately.