ESBL – how easily transmittable?

Question

Dear expert team,

Many thanks for hinting to the previous questions on ESBL. I already read their answers, but would appreciate it if my question was answered nevertheless.

I am particularly interested to know how easily ESBL is transmittable (to our daughter’s grandparents, who are at the great-grandfather’s every day) and whether a test makes sense.

Many thanks.

[Note: the following question was asked by the same questioner earlier:

Dear expert team,

Our daughter’s (4 years old, CF) great-grandfather has been diagnosed with ESBL about a year ago.

We have stopped being in touch with the great-grandfather since knowing about the germ. Now, however, our daughter’s grandmother visits the great-grandfather in his retirement home daily. I am wondering how likely it is that she as well as her husband (who has COPD) have caught ESBL. Would it make sense for both of them to get tested (if so, how?), especially given that our daughter has CF. I feel uncomfortable with this whole ESBL issue whenever the family is getting together; we have therefore been reducing contact significantly for several weeks.

Also, in the retirement home, no whole-body and mouth protection is done anymore with the great-grandfather; instead, one only points to hand disinfection and he can also move around freely in the home. Isn’t that a bit careless?]

Answer

Dear questioner,

The prevalence and transmission of "ESBL"-producing germs depends on various individual factors, which is why estimates on the risk of transmission can usually only be relative. The following comments are thus to be understood only as a means of assistance:

(1) Unfortunately, the information given in the question is incomplete, since neither the germ type (species) nor the great-grandfather’s type of colonization with "ESBL" are mentioned (as a rule, the risk of transmission in case of colonization of the respiratory tracts has to be considered higher than with solely rectal colonization). Therefore, it is impossible to judge the hygiene measures taken in the retirement home and in direct contact with the great-grandfather and they should be discussed with the staff/the person running the home (usually there is a hygiene plan that reflects the measures taken).

(2) Unquestionably, hand hygiene is the most important measure to avoid transmission during contact with germ carriers. Transmission via aerosols and colonization of the respiratory tracts can most easily be avoided by wearing a surgical mask.

(3) Susceptibility to colonization of the respiratory tracts with E.coli or Klebsialla sp. (typical ESBL-producing germs) is higher in people with COPD (grandfather) and CF (daughter) than in healthy people.

(4) Due to the special situation (granddaughter with CF, grandfather with COPD), I would consider it advisable for the grandparents to wear a surgical mask during contact with the great-grandfather.

(5) The transmission of ESBL germs in public health institutions (for susceptible people) has been described repeatedly in the literature, which is why special hygiene measures are necessary here. Transmission of ESBL-positive germs within families (household members) has hardly been researched so far but is possible as well and has been documented by some studies in the literature. By comparison, the risk of transmission in the context of elective, temporary contacts has to be considered lower.

(6) Testing contact persons outside of public health institutions in general is not recommended. Testing the grandparents for ESBL colonization may help assess the potential risk of transmission better (certainly only possible at one’s own expense). A negative result would indicate that the risk of transmission is rather low even with regular contact to the great-grandfather. However, the test can only provide a snapshot.

Finally, transmission to your daughter – even indirectly through the grandparents – cannot be ruled out completely. If the grandparents protect themselves from colonization with hand hygiene and surgical masks, the risk of transmission should at least be minimized significantly.

Kind regards
Michael Hogardt

14.01.2013