Another foundational principle was a concept called the chain of infection , a very simple but very powerful tool to help someone evaluate what you needed to do to prevent an infectious disease agent from transmitting from point A to point B , and that ’ s what cleaning and disinfecting are all about — interrupting that transmission ” — Lynne
Sehulster , PhD
The rest , as they say , is history . Sehulster ’ s background in microbiology , virology and epidemiology , as well as expertise in microbial inactivation , set her up for success at the CDC , but she says that one very specific skill was able to prepare her for the rigors of the guideline-creation process . “ My tenure at the Texas Department of Health provided me with an exposure to document preparation like state health and safety code rules , internal documents for department policy , and procedures for public health clinics ’ annual reports . That combination of document production and my microbial knowledge base was what made my move to CDC a reality .”
Sehulster worked at the CDC for 20 years , retiring in 2017 but continuing to serve as a consultant to the infection prevention and hospital epidemiology community . “ I was able to continue providing expertise to those in the industry and the healthcare community ever since . I ’ m still technically active in the field , but at a slower pace now .”
She recalls her time at the agency fondly . “ When you are in a public health setting and you interact with the CDC , you get the impression that this agency is the top of the pyramid in our world , and anyone who has an opportunity to work at the CDC , you don ’ t think for a second about it , you just go , because this is the top of the knowledge base . The experts you encounter in the agency , including the physicians , the EIS officers , the PhD scientists , and everyone in between , they ’ re at the top of their game . It was an experience that you almost can ’ t have anywhere else . It was a wonderful opportunity .”
While much has evolved in the 20 years since the EIC guideline was first issued , Sehulster reflects on how hospital practices have changed – but not without some encouragement to re-examine questionable habits .
“ Back then , we had heard that many hospitals ’ nursing and laboratory staff were conducting a lot of surface sampling . At that time , the only methods that were easily available to them was microbial sampling . After you ’ ve taken a swab of the surface and put it in the incubator , 18 to 24 hours later you see what ’ s there . That went on for many , many years , until my mentor and his supervisor Walter Bond and Dr . Marty Favero contacted the American Hospital Association and said , ‘ What are you doing with those results ?’ They reached out to the hospitals and they said , ‘ We look at the results , and we put them in the filing cabinet .’ Marty and Walter looked at each other , and after a lot of deliberation and developing a response and support for what they were going to tell the hospitals , they finally said , ‘ You know this is not very helpful if you ’ re only looking at the results , but you ’ re not acting on them .’ They were able to convince the hospitals to stop that practice , and it saved them a lot of money and time .”
Sehulster continues , “ In general in the early 1990s , healthcare facilities were aware of the Spaulding Classification , which would help them determine what strength of inactivation was available with different classes of disinfectants , and I think they understood that you ought to clean surfaces appropriately in the healthcare setting . But they certainly didn ’ t have a lot of the technology that we have today , which makes cleaning and disinfection easier and more effective . So , the principles that we use today were there in the 1990s , but the means to enable those principles weren ’ t quite there .”
She adds , “ Another foundational principle was a concept called the chain of infection , a very simple but very powerful tool to help someone evaluate what you needed to do to prevent an infectious disease agent from transmitting from point A to point B , and that ’ s what cleaning and disinfecting are all about -- interrupting that transmission ,” she adds . “ With every opportunity to converse with infection prevention and environmental services personnel , I tell them , if you ’ re encountering a problem that has an infectious disease issue associated with it , use the chain of infection to begin to answer the question , ‘ Is this pathogen variable ? How does it get from Point A to Point B ? When it gets to Point B , is there a portal of entry into the patient ?’ Once you have all those elements answered , you can construct an infection prevention and control strategy , including what disinfectant you need to use and its potency . It ’ s a no-brainer . It is so simplistic , and it ’ s fascinating how effective it is .”
“ Shortly before the EIC guideline was released in 2003 , at that point the document was considered finalized , and no other changes were going to be made . But in March 2003 , we heard about SARS emerging from China and many people were wondering , do we need to change anything we ’ re doing ? Again , this is where the chain of infection comes into play . Plus , microbiologists getting access to any new pathogen will try to scientifically determine if it ’ s a virus , what family of viruses it belongs to , is it enveloped or is it simply a protein-based capsule ? Is it a virus that requires bloodborne , airborne or foodborne transmission ? All these questions must be answered . Once you get the answer , then you can determine what is the best course of action to prevent it from spreading from one person to another . All these things are in place , we just have to use them .”
One of the unique characteristics of the EIC , Sehulster points out , is that it synthesizes several guidelines into one comprehensive document .
“ When you look at the table of contents , you quickly realize that this is not a guideline on one topic , it is really seven guidelines under one binding ,” she says . “ That meant that myself and my HICPAC advisor , Raymond Chinn , MD , had to recruit content contributors , most of whom were in the CDC . I turned out to be the primary contributor for sections like environmental surface sampling , the role of animals in healthcare ( specifically service animals ), the
16 june 2023 • www . healthcarehygienemagazine . com