Resolution of infectious parameters after antimicrobial therapy in patients with ventilator-associated pneumonia.

Although recommended durations of antimicrobial therapy for ventilator-associated pneumonia (VAP) range from 7 to 21 d, these are not based on prospective studies and little is known about the resolution of symptoms after start of antibiotics. Resolution of these symptoms was investigated in 27 patients. VAP was diagnosed on clinical, radiographic, and microbiological criteria, including quantitative cultures of bronchoalveolar lavage. All patients received appropriate antibiotic therapy. Highest temperatures, leukocyte counts, Pa(O(2))/FI(O(2)) ratios, and semiquantitative cultures of endotracheal aspirates were recorded from start of therapy until Day 14. Resolution was defined as the first day that these parameters fulfilled the following definition: temperature < or = 38 degrees C, leukocytes < or = 10 x 10(9)/L, Pa(O(2))/FI(O(2)) ratio > or = 25 kPa, and no or +1 of bacterial growth of etiologic pathogens in cultures of endotracheal aspirate. VAP was caused by Enterobacteriaceae (n = 14), P. aeruginosa (n = 7), S. aureus (n = 6), H. influenzae (n = 3), and S. pneumoniae (n = 1). H. influenzae and S. pneumoniae were eradicated from tracheal aspirates, whereas Enterobacteriaceae, S. aureus, and P. aeruginosa persisted, despite in vitro susceptibility to antibiotics administered. Significant improvements were observed for all clinical parameters, most apparently within the first 6 d after start of antibiotics. Newly acquired colonization, especially with P. aeruginosa and Enterobacteriaceae, occurred in the second week of therapy. Six patients developed a recurrent episode of VAP, four of them with P. aeruginosa. Clinical responses to therapy for VAP occur within the first 6 d of therapy, endotracheal colonization with Gram-negative bacteria persists despite susceptibility to therapy, and acquired colonization usually occurs in the second week of therapy and frequently precedes a recurrent episode.

The economic implications of animal diseases and disease control at the national level.

The authors examine the economic implications of animal diseases and control programmes at the national level, including the role of government in animal health, the effect of regulations and the use of cost-benefit analysis. Special attention is paid to the role of economic analysis in government decision-making processes. Economics provides a framework for gathering information and for the presentation of that information in a methodical manner, thereby providing a method for the decision maker to examine policy alternatives. In addition, assumptions underlying the analysis must be clearly laid out and explained by the person undertaking the analysis. Economic reasons for government intervention in animal health programmes include externalities, natural monopolies, public goods, coordination failure, information failure and distribution issues. An integrated holistic approach that includes national and international policy objectives is outlined in the paper. In the approach outlined, government coordinates the activities of stakeholders in animal health, including producers, consumers and researchers.