There are times when writing silly clichés or phrases that an image randomly pop into my mind of how a blog is going to develop. Last week I closed the "I'll take Kill Claims for $200" by introducing the focus of this week's blog: "Fast Kill Times and Acceptable Wet-Contact Time To Ensure Proper Disinfection of Non-Critical Surfaces and Patient Care Equipment," knowing that this week would be "round 2" or "take 2" in the discussion of the "Selection of the Ideal Disinfectant" paper. The idea of "take 2" invoked not an image of continuing the dissection of this article, but a very sobering image of a stopwatch, and the thought that we do not have the luxury of time in any of the markets that use disinfectants to have a "take 2" or reapply a product more than once to ensure disinfection occurs. A very fitting image for the focus of this blog.
As the title of the section of the article implies, Drs. Rutala and Weber discuss the merits of contact time as it relates to disinfection.The focus of Lee's blog "Dirty to Disinfected in 60 seconds Flat" was entirely focused on this concept. I could go on ad nauseam on this topic citing numerous examples of why rapid contact times are important, but I think Drs. Rutala and Weber summed it up nicely with their statement "fast kill times are important because they give you confidence that you are killing the prevalent and most common healthcare-associated pathogens before the disinfectant solution can dry".
Which leads to the next area of discussion - wet dwell time. Again, Lee's "Premature Evaporation - Is your disinfectant fulfilling your every need?" blog sums this discussion up very well and as Drs. Rutala and Weber explain, if a product evaporates too quickly it will not stay in contact with the organism we are trying to kill for the amount of time that the product needs. For this reason, the best disinfecting products will have a wet dwell time that is greater than or equal to the kill times listed on the label. However, this does not mean that we need to use the longest contact time as listed on the label. Many products may have longer tuberculocidal or fungicidal contact times for Candida as an example. However, surfaces contaminated with Candida, non-tuberculosis mycobacteria or other fungi have RARELY been shown to be a risk factor for HAIs. As Drs. Rutala and Weber highlighted in the first section of this article, vegetative bacteria cause upwards of 80% of all HAIs and should be the organisms we focus on with respect to choosing a rapid and effective disinfectant.
The last area in this section that is discussed is around the concept of persistent or sustained antimicrobial activity of a disinfectant. Certainly this idea has merit and considerable interest as the ability for a surface to aid in the killing or neutralizing of a pathogen would mean that we would have a back up or "CYA" to act as a fail safe for surfaces that did not get cleaned and disinfected correctly the first time. While sustained antimicrobial activity may eliminate the problem of recontamination, current products have limitations such as cost and the fact that they can be removed by touch or contact. Further, their use has not been demonstrated to have a direct impact on reduction of HAIs as compared to disinfectants that do not have sustained antimicrobial activity. Basically, the idea is intriguing, but needs more evidence to determine if this is an effective expenditure or not. Personally, if you have some extra money in your budget, you should hire another housekeeper or two and implement a program to disinfect all high touch surfaces within your facility twice per day.
Stay tuned for next week's concluding blog that will focus on "Safety, Ease of Use and Other Factors" to consider when choosing a disinfectant.