Navigation Links
Math model identifies key to controlling epidemic
Date:2/17/2008

When you check into a hospital, the odds are one in ten that you will become infected with a strain of antibiotic-resistant bacteria as a result of your stay. That is because the problem of drug-resistance has become endemic in todays hospitals despite the best efforts of the medical profession. In the United States alone this currently causes about 100,000 deaths per year.

Now, a sophisticated new mathematical model has identified what may be the key to getting this growing health problem under control: Changing the way that antibiotics are prescribed and administered.

We have developed the mathematical model in order to identify the key factors that contribute to this problem and to estimate the effectiveness of different types of preventative measures in typical hospital settings, said Vanderbilt mathematician Glenn F. Webb, who described the results at a presentation at the annual meeting of the American Association for the Advancement of Science on Feb. 17 in Boston.

According to our analysis, the most effective way to combat this growing problem is to minimize the use of antibiotics, he said. It is no secret that antibiotics are overused in hospitals. How to optimize its administration is a difficult issue. But the excessive use of antibiotics, which may benefit individual patients, is creating a serious problem for the general patient community.

For example, the model calculates that in a hospital where antibiotic treatments are begun on average three days after diagnosis and continued for 18 days, the number of cross-infection by resistant bacteria (that is, cases where patients are accidentally infected by health care workers who have been exposed to these bacteria while treating other patients) waxes and wanes but never disappears completely. However, when antibiotic treatments are begun on the day of diagnosis and continued for eight days, the cross-infection rate drops to nearly zero within 250 days.

The model was developed by an interdisciplinary team of researchers. In addition to Webb, the contributors are Erika M.C. DAgata at Harvard Universitys Beth Israel Deaconess Medical Center, Pierre Magal and Damien Olivier at the Universit du Havre in France and Shigui Ruan at the University of Miami, Coral Gables. It is described in the paper Modeling antibiotic resistance in hospitals: The impact of minimizing treatment duration published in the Journal of Theoretical Biology in December 2007.

The researchers constructed a two-level model: (1) the bacterial level where non-resistant and resistant strains are produced in the bodies of individual patients and (2) the patient level where susceptible patients are cross-infected by health care workers who have become contaminated by contact with infected patients.

At the bacterial level, the model takes an ecological approach that describes the competition between non-resistant and resistant strains of infectious bacteria. In untreated patients, non-resistant bacteria have a competitive advantage over the resistant strains that keeps the numbers of resistant bacteria extremely low. During treatment, however, the antibiotics kill off the normal bacteria and that allows the resistant strain to take over. As a result, a patient on antibiotics becomes a potential source of infection with resistant bacteria. This continues as long as the treatment lasts. After the treatment is ended, the population of non-resistant bacteria of all types rebounds and the population of resistant bacteria begins to drop until the patient ceases acting as a source.

What is going on at the bacteria level is linked with the second level which models the interactions between patients and hospital care workers who carry the bacteria from patient to patient. In order to account for individual variations in behavior, the researchers developed an individual based model that views patients and workers as independent agents. They then used a method called a Monte Carlo simulation to simulate the spread of the different strains of bacteria under various conditions by generating thousands of probable scenarios using random values for uncertain quantities.

The mathematical analysis reveals that the optimal strategy for controlling hospital epidemics is to start antibiotic treatments as soon as possible and administer the drugs for the shortest possible time. Beginning treatment as early as possible is the most effective in knocking down the population of the non-resistant bacteria that is causing a patients initial illness and minimizing the length of treatment shortens the length of time when each patient acts as a source of infection.

Currently, hospitals are concentrating on improving hygiene to combat this problem. The model confirms that improvements in hygiene can substantial reduce the frequency of cross-infections. The model also demonstrates that hygiene alone may not be sufficient and improving the way antibiotics are administered will be necessary to eliminate the problem of resistant bacteria.

Our results point out an urgent need for more research into the issue of the best timing for the administration of antibiotics and how to reduce its misuse and overuse, said Webb.


'/>"/>

Contact: David F. Salisbury
david.salisbury@vanderbilt.edu
615-343-6803
Vanderbilt University
Source:Eurekalert  

Related medicine news :

1. Chromatin remodeling complex connected to DNA damage control
2. Health care incentive model offers collaborative approach
3. Novel 3-D cell culture model shows selective tumour uptake of nanoparticles
4. 4-Star Gen. Barry McCaffrey, Former U.S. Drug Czar, to Address National Drug Crisis, Keynote Grand Opening of New Allenwood, PA National Model Detox Center
5. A classic method for modeling skin cancer is featured in Cold Spring Harbor Protocols
6. New knock-out gene model provides molecular clues to breast cancer
7. Rain Man mice provide model for autism
8. University of Nevada School of Medicine Professor Confirms Accuracy Through Validation Study Using the CSI Health Station Model 6K
9. USC researcher identifies stem cells in tendons that regenerate tissue in animal model
10. Americas Next Top Model Steps up for Psoriasis Awareness
11. Computer models help raise the bar for sporting achievement
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Math model identifies key to controlling epidemic
(Date:6/25/2016)... ... 25, 2016 , ... Conventional wisdom preaches the benefits of moderation, whether it’s ... setting the bar too high can result in disappointment, perhaps even self-loathing. However, those ... goal. , Research from PsychTests.com reveals that behind the tendency to ...
(Date:6/24/2016)... ... June 24, 2016 , ... Marcy was in a crisis. Her son James, eight, was out ... family verbally and physically. , “When something upset him, he couldn’t control his emotions,” remembers ... would throw rocks at my other children and say he was going to kill them. ...
(Date:6/24/2016)... ... June 24, 2016 , ... Comfort Keepers® of San ... Society and the Road To Recovery® program to drive cancer patients to and from ... adults to ensure the highest quality of life and ongoing independence. Getting to ...
(Date:6/24/2016)... New York, NY (PRWEB) , ... June 24, ... ... lifestyle publication Haute Living, is proud to recognize Dr. Barry M. Weintraub as ... believes that “the most beautiful women in the world, and the most handsome ...
(Date:6/24/2016)... ... ... Venture Construction Group (VCG) sponsors Luke’s Wings 5th Annual ... Country Club at 1201 Rockville Pike, Rockville, Maryland, 20852. The event raised funds ... been wounded in battle and their families. Venture Construction Group is a 2016 Silver ...
Breaking Medicine News(10 mins):
(Date:6/23/2016)... June 23, 2016 Research and ... Excipients Market by Type (Organic Chemical (Sugar, Petrochemical, Glycerin), ... Topical, Coating, Parenteral) - Global Forecast to 2021" ... The global pharmaceutical excipients market is projected ... CAGR of 6.1% in the forecast period 2016 to ...
(Date:6/23/2016)... DUBLIN , June 23, 2016 ... "Global MEMS Devices Medical Market Analysis 2016 - Forecast to ... The report contains up to date financial ... reliable analysis. Assessment of major trends with potential impact on ... dive analysis of market segmentation which comprises of sub markets, ...
(Date:6/23/2016)... 2016 Bracket , a leading clinical trial ... clinical outcomes platform, Bracket eCOA (SM) 6.0, at the ... – 30, 2016 in Philadelphia , Pennsylvania.  ... Assessment product of its kind to fully integrate with RTSM, ... eCOA 6.0 is a flexible platform for electronic clinical outcomes ...
Breaking Medicine Technology: