Understanding and modelling reservoirs, vehicles and transmission of ESBL-producing Enterobacteriaceae in the community and long term care facilities
Infections with antibiotic resistant bacteria, for example an urinary tract infections, are difficult to treat. Because of this, antibiotic resistance is an important public health threat. In Europe, the ESBL-producing gut bacteria (ESBL-G), are the most important cause of such infections, with around 400.000 cases per year. 5% of the Dutch inhabitants carries ESBL-G, while outside the Netherlands percentages are often much higher. Most people carry ESBL-G unnoticed, which hampers the prevention of spread of these bacteria in the population.
Aim
This project studied the spread of ESBL-G in 71 households, and 6 long term care facilities in Western-Europe. The role of food, surfaces, and wastewater was also assessed.
Methods
The genetic code of ESBL-D was determined to assess if certain variants of ESBL-G were more prevalent amongst humans. Secondly, the genetic code was used to assess if loose genetic elements, encoding for antibiotic resistance, were exchanged between bacteria. If so, this exchange would lead to additional spread of antibiotic resistance within households and long term care facilities.
Results
The most important conclusions of this research project were: (i) ESBL-G transmission within households and long term care facilities was frequent. Cleaning and general hygiene are effective measures to prevent the spread of ESBL-G. (ii) Transmission of ESBL-G through food was rare. (iii) Evidence was found for exchange of genetic material encoding for antibiotic resistance between bacteria. More research is needed to quantify the role of this within the spread of ESBL-G.
The most important findings about households
Most household members of a known ESBL-positive household member also carried ESBL-G during the study period. Care-assistance was associated with an additional risk to become ESBL-positive. Advice for hygiene, for example during care-activities, to households with a known ESBL-positive household member, could potentially be useful for prevention of ESBL-G transmission.
The most important findings about long term care facilities
ESBL-G was present in all long term care facilities. However, transmission occurred mostly in the 2 participating Spanish facilities. ESBL-G was additionally more often found on frequently touched surfaces of the Spanish facilities. Thorough cleaning and general hygiene are important to prevent the spread of ESBL-G in long term care facilities.
The most important findings about food and wastewater
ESBL-G mostly spreads through human-to-human transmission. Transmission via food is likely rare. Wastewater potentially contributes to human-to-human spread of ESBL-G.
The most important findings about genetic codes
Evidence was found for exchange of genetic material encoding antibiotic resistance between bacteria. More research is needed to understand quantify how this exchange contributes to the human-to-human spread of ESBL-G.