E. coli, CRISPR, Biases in Our Understanding of Phage Ecology, and Possible Implications for Phage Therapy

Stephen T. Abedon

Department of Microbiology – The Ohio State University

phage.org – phage-therapy.org – biologyaspoetry.org


We’re all biased by what we know best and the link below discusses why, historically as well as microbiologically, we all “grew up” with the notion that envelope mutations are the primary means by which phage resistance evolves in bacteria. So thank you E. coli (I state with sarcasm):


What, I ask, are the implications for phage therapy of resistance mechanisms to specific phages that are essentially cost free and, at least arguably, Lamarckian as well, i.e., as due to CRISPR? For well-trained phage-therapy teams, I suspect not much. This is because, whether employing cocktails or monophages, the intention generally will be to hit bacterial targets hard and with whatever it takes to clear the infection, such as to switching phages during monophage therapy if resistance is noted.

But for monophages in the hands of less well-trained individuals, e.g., over-the-counter phage formulations or in the hands of poorly trained or regulated clinicians, the potential for development and then transmission of fully fit pathogens that nonetheless are fully resistant to a specific monophage could be fairly high. Importantly, and as relevant to the cited E. coi-CRISPR story, this issue may be more relevant for some pathogens, i.e., those with intact CRISPR systems, than it is for others.

So perhaps we can add inhibition of the potential for therapy-induced evolution of phage resistance among pathogens – as could then be transmitted across affected human communities – as an additional advantage of  prêt-à-porter (phage cocktails) versus sur-mesure (monophage therapy), while still retaining an argument for sur-mesure particularly among highly experienced phage therapists.

As we note in Chan and Abedon (2012), I nevertheless don’t buy arguments that spontaneously occurring phage host range mutations can be counted on in situ to counter bacterial evolution to phage resistance whether in the context of phage cocktails or instead monotherapy. From p. 19 of that publication:

A further consideration is that just as cocktails of phages may be thwarted in their ability to target low densities of phage-resistant bacteria, particularly given active treatment, these concerns should be even greater if one is relying on in situ phage evolution to supply resistance-countering phages… The reason for this is that the necessary host-range mutant phage types will be present in even lower densities than the phages explicitly found in cocktails. These same concerns may also be seen even in the absence of spatial structure so long as those phages within a cocktail that are amplified in situ, that is, in the course of active treatment, are not the same phages to which bacterial phage-resistant mutants are sensitive… Active therapy even with phage cocktails thus may be inherently incompatible with early interference with the evolution of bacterial resistance to phages.


Phage cocktails nevertheless should be better suited than monophages for dealing with evolving bacterial resistance to phages simply because cocktails inherently possess greater total numbers of phage particles that display divergent host ranges. On the other hand, the generation of cocktails of phages that display divergent host ranges – but where those phages nevertheless have been derived from a common genetic “platform” – might be expected to perform little better than monophages in the face of CRISPR-mediated phage resistance in target bacteria.

Further (Phage Therapy) Reading:

Chan, B. K., S. T. Abedon, and C. Loc-Carrillo. 2013. Phage cocktails and the future of phage therapy. Future.Microbiol. 8:769-783. [PubMed]

Chan, B. K. and S. T. Abedon. 2012. Phage therapy pharmacology: phage cocktails. Adv.Appl.Microbiol.  78:1-23. [PubMed]

Pirnay, J. P., V. D. De, G. Verbeken, M. Merabishvili, N. Chanishvili, M. Vaneechoutte, M. Zizi, G. Laire, R. Lavigne, I. Huys, G. Van den Mooter, A. Buckling, L. Debarbieux, F. Pouillot, J. Azeredo, E. Kutter, A. Dublanchet, A. Gorski, and R. Adamia. 2011. The phage therapy paradigm: prêt-à-porter or sur-mesure? Pharm.Res 28:934-937. [PubMed]


Importance of Specificity

Stephen T. Abedon

Department of Microbiology – The Ohio State University

phage.org – phage-therapy.org – biologyaspoetry.org


This article is not yet fully out but certainly is intriguing: http://www.cell.com/cell/abstract/S0092-8674(15)00003-3

The title is “Disease-Specific Alterations in the Enteric Virome in Inflammatory Bowel Disease” by Norman et al.

The basic premise is that phages may very well be knocking out beneficial bacteria, in the gut, resulting in disease.

Here is a synopsis: https://www.sciencenews.org/article/when-bacteria-killing-viruses-take-over-it%E2%80%99s-bad-news-gut

To me what’s particularly interesting about this study, what little currently can be easily accessed, is that it actually can be viewed as an argument for the benefits of phage specificity in the guise of phage-mediated biocontrol of bacteria, i.e., phage therapy as applied clinically.

Specifically (if you will pardon the pun), when phages are employed in phage therapy, there is at best an only low potential that beneficial bacteria will be directly affected because phage host ranges tend to be quite narrow, typically at best spanning a single bacterial species and potentially some members of closely related genera. This contrasts with the typical antibiotic, which can be much less discriminatory in its impact on normal microflora, potentially resulting in bacterial superinfections.

Indeed, some antibiotics even can induce prophages, resulting in antibiotics potentially giving rise to excessive phage numbers that can impact beneficial bacteria. It is even possible for antibiotics to have an indirect impact by killing off certain bacteria that might then allow an overgrowth of beneficial bacteria which in turn could result in an achievement of so-called “winner” densities. Excessively high densities of specific bacterial types may then be followed by phage-induced reductions in the presence of these beneficial bacteria to below those levels present prior to antibiotic exposure (and then potentially overgrowth of harmful bacteria).

Sure these scenarios are complex and the latter certainly speculative. But the bottom line nonetheless is this: Some phages are bad – and we know this already since many phages carry bacterial virulence factor genes – but not all phages are bad, and those phages that are good in many or most instances probably give rise to somewhat less negative impact on the body than the majority of antibiotics.

Celebrate the diversity of phages, and their specificity!

Phage-Mediated Biocontrol of Plant Pathogens (2001 to “current”)

Stephen T. Abedon

Department of Microbiology – The Ohio State University

phage.org – phage-therapy.org – biologyaspoetry.org


I gave the opening talk at the 2nd International Symposium, “New Stages of Phage Biocontrol of Plant Diseases”, held September 18, 2014, at Hiroshima University, Japan. Though my talk was at best peripheral to the emphasis of the symposium, i.e., watch here, I did strive to get into the spirit of things by tracking down references to phage-mediated biocontrol of plant pathogens. Clearly I did not succeed in finding every last one of these references, but nevertheless I probably IDed the ones that “everybody” in the field knows about, and maybe perhaps then some. I’ve sorted these by year plus have indicated the target pathogen as well as the disease that is caused by that pathogen. Where possible I’ve provided a link to the article, though note that I’m providing no promises regarding your potential to find all of these articles online for free! Shown only are experimental articles, and note that I have not confirmed the validity of many of these. So if you know better, or can otherwise help by adding to this list, please let me know!

Here are those papers published in the Twenty-First Century (2001 and newer) up to at least the date of my talk:

Continue reading

Going Bottomless in the Plaque World

Stephen T. Abedon

Department of Microbiology – The Ohio State University

phage.org – phage-therapy.org – biologyaspoetry.org


Bottom agar = Hard agar = Solid media

Top agar = Soft agar = Sloppy agar = Semi-Solid media.

I’m embarrassed to say that I’ve had this article in my reference database since August of 2007: Rizvi, S., Mora, P.T. (1963). Bacteriophage plaque-count assay and confluent lysis on plates without bottom agar layer. Nature 200:1324-1325. It is only today, however, and apparently as a form of avoidance behavior (there’s a talk I’m supposed to be working on), that I’ve obtained the reprint and set out to read it.

Their second sentence reads, “Having spent considerable time on preparation of ‘bottom’ agar plates for the agar layer assay by the plaque count method and for high-titre bacteriophage stock preparation on a large number of plates by the confluent lysis method…” And thus they are off striving to do something about this by investigating “…the possibility of saving time by using plates without ‘bottom’ agar for assay and stock preparation.”

The media they used for their ‘bottomless’ agar consisted of the following:

  • 10 g Difco bacto-casamino-acids (acid hydrolysed casein)
  • 15 g Difco bacto-nutrient broth
  • 10 g Sucrose
  • 1g Dextrose
  • 5g Crystalline magnesium sulphate
  • 5 g Sodium chloride
  • 8g Agar

Efficiencies of plating in testing phages T1 through T7 they found to be essentially 100% for T1, T3, and T7, and basically 50% for the rest. To the extent that my interpretation of the ‘smudges’ provided in Nature’s PDF can be trusted, the per plate yields for confluent lysis phage preps were more or less the same with versus without bottom agar. Consistently for the latter they note: “The yields obtained on plates without ‘bottom’ agar were slightly better than the yields obtained on plates with ‘bottom’ agar.”

They also note that, “Confluent lysis can be adapted for large-scale bacteriophage production by carrying it out on large stainless steel trays.”

Historical Referencing:

These authors also cite four, mostly Mark Adams-dominated publications for plaque count method (first three) and confluent lysis stock preparation (last). These are:

(1) Gratia, A. (1936). Des relations numeriques entre bactéries lysogenes et particules de bacteriophage. Ann. Inst. Pasteur, 57:652-676.

(2) Adams, M. H. (1950). Methods of Study of Bacterial Viruses. (Methods in Medical Research, 2:1) The Year Book Publishers, Inc., Chicago.

(3) Adams, M. H. (1959). Bacteriophages. Interscience Publishers, Inc., New York.

(4) Swanstrom, M., and Adams, M. H. (1951). Agar layer method for production of high titer stocks. Proc. Soc. Exp. Biol. and Med. 78:372-375.

Ambiguous Phage Terms

Stephen T. Abedon

Department of Microbiology – The Ohio State University

phage.org – phage-therapy.org – biologyaspoetry.org


All fields employ specialized terms and at a minimum it is helpful for those individuals working in a field to both know and agree upon what those terms mean. As no doubt is also the case for most or all other fields, in phage biology there are a number terms that nonetheless possess ambiguous meanings. Here I provide both a list and brief discussion of my personal top-ten list of ambiguously defined or otherwise improper phage terms. Note that in many cases it generally is good practice to be aware of and then define ambiguous terms as you use them; this is so that your reader will understand what specific meaning you may be hoping to convey. Here then, in alphabetical order, is my list of top-ten ambiguous phage terms and why I’ve placed them on the list.

  1. Adsorption – This term is not so much ambiguous as potentially covering far too much ground. It can be used to describe the entire process of phage acquisition of a host bacterium, from diffusion through collision with a bacterium, attachment, virion conformational change, and even nucleic acid translocation. Alternatively, it can just mean attachment, though even that can be reversible attachment versus irreversible. In this case actually defining your intended meaning is not necessarily important, though keeping in mind the term’s ambiguous nature can’t hurt.
  2. Capsid – Though scientifically I “grew up” considering the entire phage particle sans the nucleic acid – and sans also the envelope, if present – as the capsid, in fact the capsid can be distinguished, in tailed phages, from the tail. The capsid thus surrounds and serves to contain and protect the nucleic acid and can contrast with other proteinaceous virion appendages which have other functions such as phage delivery into the adsorbed host cell.
  3. Carrier state – Different sub-fields use this term differently. Indeed, almost everybody uses this term with different meanings. If somebody says to you, “Carrier state”, you probably will assume that the intended meaning is whatever it is that you typically think the intended meaning should be. A little piece of advice: Don’t bet large amounts of money on that assumption.
  4. Lysis from without – Lysis from without is a term that almost makes me want to cry. There generally are four definitions used for the term, two of them both correct and distinct and two of them simply are wrong. If a phage particle, particularly when applied in high densities, lyses a target bacterium and does so well prior to the normal end of that phage’s latent period, then that’s lysis from without. If an endolysin is purified and then applied to a bacterium externally, resulting in lysis, then that also is lysis from without. By contrast, if you add large numbers of phages to a bacterium and the bacterium dies, that has almost no meaning except that phages can kill bacteria. As for the fourth usage, if you observe confluent clearing in the course of a spot test, then that’s a zone of inhibition rather than necessarily lysis from without, just like the zones of inhibition that antibiotics produce. Spot formation in fact says absolutely nothing about the lytic behavior of the phage applied other than that the phage in the numbers applied, or even the carrying fluid, can appreciably kill the target bacteria.
  5. Lysogenic phage – Bacteria are lysogenic. That is, if they contain a prophage then they have the potential to generate lysis in a second bacterial strain following the mixing of cultures. What people mean to say when they say lysogenic phage is temperate phage. Lysogenic phage is ambiguous in the sense that it is a misapplied term. Please, just don’t use it.
  6. Lytic phage – So, what is a lytic phage? A phage that lyses bacteria? What kind of information does that supply? That it isn’t a chronically released phage? Is that the intended meaning when “lytic” is used as a qualifier for “phage”? Sometimes, yes it is. Usually, though, the term lytic phage seems to be used to mean non-temperate. The logic of this meaning, however, is not necessarily well worked out since most temperate phages technically are also lytic phages and temperate phages also can lyse cultures of bacteria. Traditionally, people have used the term “Virulent” to describe non-temperate, non-chronically releasing phages. I prefer obligately lytic since the term virulent as applied to phages also, technically, is ambiguous. Nevertheless, in the case of “Virulent phage” there is sufficient tradition that I’ll, at least within the context of this discussion, let this latter concern slide.
  7. Multiplicity of infection – Once upon a time people did phage experiments starting with high bacterial densities and almost all of the phages adsorbed. Thus, multiplicity of infection could be thought of as the ratio of added phages to bacteria. Some careful souls pointed out that you really do need to measure adsorption efficiency before making this claim since the real meaning of multiplicity of infection is literally multiplicity of infection, that is, the ratio of the number of successfully infecting or at least successfully adsorbing phages to the number of target bacteria that the phages had been added to. In the more modern literature, however, people started adding phages to low densities of bacteria and then claimed that this ratio of added phages to target bacteria too is the multiplicity of infection. It’s not. At best it’s the phage multiplicity of addition.
  8. Rise – OK, this one is not something that people generally have problems with since it’s rarely used. Nonetheless, this is my list and the bacteriophage rise is a concept that I care about. The rise traditionally refers to a culture’s increase in phage titer as seen over the course of single-step growth curves (a.k.a., one-step growth curves). The phage titers after a certain point literally rise, hence this is the rise. The rise is not the increase in number of phage virions found inside of bacteria prior to phage-induced bacterial lysis. So far as I know, that latter concept does not actually have a standard, well agreed upon descriptor. As the term “Rise” already exists to describe a different phenomenon, however, it should not be used also within this latter, intracellular context.
  9. Pseudolysogeny – Not only is this term used to describe a multitude of phage phenomena, for the most part we don’t have all that much of a mechanistic understanding of any of them. It is probably a really good idea, therefore, to do one’s best to avoid using this term. But if you must use it, then explicitly and unambiguously define it in terms of what pseudolysogeny means to you. I’ve personally identified literally more meanings of pseudolysogeny than I care to count; see my 2009 reference, below, so that you can count them for me.
  10. Spot versus Plaque – Spots and plaques are not the same thing and a plaque never should be called a spot even though they sort of look like tiny spots. Similarly, a spot should never be called a plaque even though they sort of look like and can even act like giant-sized plaques. The distinction? A plaque is initiated with a single infective center, that is, approximately a point source of subsequent phage production. A spot is initiated with multiple infective centers, that is, multiple point sources of potential phage production that converge into a single zone of clearing. In addition, while plaque formation is absolutely dependent on productive phage infections (those infections that produce phage virions), a spot can form solely by killing bacteria, i.e., without also producing phage progeny.

And here’s a bonus term: Abortive infection. Just so that everybody is on the same page, the ability of some phages under some conditions to form spots without also producing new phages is a consequence of phages killing bacteria without also going through a normal infection cycle. That is, an abortive infection. Confusingly, lysis from without, in its original meaning (i.e., as listed first, above) is a form of abortive infection. Even more confusing, the means by which abortive infections are assayed, using measurements of what is known as efficiency of plating, can include not just phages that kill bacteria without also producing new phages but also phages that kill bacteria while producing new phages but not, under the same conditions, enough new phages to also produce plaques. I describe the latter as a “Reduced infection vigor”. Ecologically that distinction is an important one but more important is to realize that there exist numerous examples of phages killing bacteria without necessarily also vigorously producing new phages.

Presumably there are additional ambiguous phage terms out there and if I thought about it further, then I probably could ID a few more as well. Others also will have their own personal pet peeves which they too might consider blogging about. In any case, don’t forget that it can be helpful to define your terms as you use them. Done properly, then your audience will know what you mean. Your meaning might not be their meaning, but in theory at least nobody can complain if you explicitly explain exactly what it is that you are trying to say.

Further reading:

Abedon, S. T. (2009). Disambiguating Bacteriophage Pseudolysogeny: An Historical Analysis of Lysogeny, Pseudolysogeny, and the Phage Carrier State. In: Contemporary Trends in Bacteriophage Research. Adams, H. T. (ed), Nova Science Publishers, Hauppauge, New York, 285-307

Abedon, S. T. (2011). Lysis from Without. Bacteriophage 1(1):46-49. [PubMed link]

Hyman, P., Abedon, S. T. (2009). Practical Methods for Determining Phage Growth Parameters. Methods in Molecular Biology 501:175-202. [PubMed link] (for consideration of the phage multiplicity of infection and rise)

Hyman, P., Abedon, S. T. (2010). Bacteriophage Host Range and Bacterial Resistance. Advances in Applied Microbiology 70:217-248. [PubMed link] (for consideration of abortive infections)

See also the terms list found in phage.org.

Phage Therapy Case Study from 1936

Stephen T. Abedon

Department of Microbiology – The Ohio State University

phage.org – phage-therapy.org – biologyaspoetry.org


This article can’t be found via a PubMed search but can be found here: jama.jamanetwork.com/article.aspx?articleid=1156439. It is not free, but most of it can be found on that page. The reference is Morrison, S., Gardner, R.E. (1936). The Treatment of a Lung Abscess due to Bacillus coli with a Lytic Filtrate. JAMA 107(1):33-34. It is a fascinating account because it walks you through the case in some detail plus presents both efficacy and side effects, neither of which can be unquestionably attributed to the phage itself since the formulation used was not purified. Still, pretty amazing stuff, and I quote:

N, S., a woman, aged 22, who had previously been in excellent health, suddenly experienced a severe diffuse abdominal pain, Aug. 5, 1934… On the third day the patient’s condition became critical and she was rushed to the Chambersburg (Pa.) Hospital, where an emergency operation was performed by Dr. L. H. Seaton. When the abdomen was opened a gangrenous appendix with generalized peritonitis was disclosed. The remainder of the appendix was removed and drains were inserted…

[Approximately one month later,] after an excruciating pain, examination disclosed massive collapse of the left lung. During the subsequent few days slight signs of partial return of pulmonary function were observed, but relapse followed. Clinical and x-ray signs of effusion developed. Aspiration was performed September 12 and 500 cc. of very heavy purulent material with a foul and typical colon odor was obtained. A culture of the pus at this time yielded only Bacillus coli. Three days later, because the material was too thick to be aspirated, rib resection was done with a virtual gush of pus. A bronchial fistula developed shortly after the rib resection and the patient was expectorat¬ ing the same kind of material as that which drained from the resection wound. The appearance of the area around the resection opening was necrotic and “mossy” and failed to show any improvement on local irrigations with 1,000 cc. of saline solution twice a day. Digital examination through the resection wound disclosed many walled off abscesses surrounded by necrotic tissue. In view of the hectic fever and the general condition, which indicated toxic absorption, an especially resistant abscess which failed to open was incised by an approach between the ribs just above the rib resection. A drain was inserted and in a few days healing took place.

A second sample of pus was collected at this time (September 16) and another pure culture of colon bacillus isolated which was fairly readily lysed by a bacteriophage that was active against various strains of B. coli isolated from other sources.

After a cutaneous test September 20 of 0.1 cc. of the lytic filtrate twelve hours previously had given little or no reaction, and after irrigating the chest with 1 liter of physiologic solution of sodium chloride, 1 ounce (30 cc.) of the phage was instilled and allowed to remain for two hours. This was followed saline irrigation and the wound covered by a dressing saturated with the bacteriophage. The following day the observation was made that the discharge had become thin and watery and had lost its offensive character for the first time since the resection was done five days before, even though saline irrigations had been administered twice daily during this five day period. A second and equally remarkable change had occurred at the resection wound itself, where the mossy, necrotic character was entirely changed to a clean, fresh, healthy appearing incision.

Since the first use of bacteriophage had given such excellent results, a second application seemed indicated, and therefore the procedure was repeated. However, within ten minutes a violent generalized rose-colored urticaria appeared and the patient complained of nausea and vomited. The bacteriophage was drained immediately and the chest irrigated with large quantities of saline solution. Epinephrine was administered…

After such a marked allergic reaction to the bacteriophage had occurred it was decided to discontinue bacteriophage instillations and continue only with saline irrigations and external dressings saturated with bacteriophage. The dressings of bacteriophage were continued for a week along with irrigations of physiologic solution of sodium chloride. Throughout this period the resection wound maintained its healthy normal appearance and the discharge remained clear, watery and nonodorous. The temperature reached 102.2 F. each day for the thirteen days prior to the urticarial reaction. On that day the reading was 103.2 F. after the reaction. After this reaction the temperature did not go above 102.2 F.

The patient’s general condition was remarkably improved and within six weeks she was able to leave the hospital. The appendiceal wound had healed but the fever, less hectic in type, continued as well as the thin nonodorous drainage. At home the fever gradually subsided as well as the drainage, and heal¬ ing was practically complete toward the end of December.

Whether the bacteriophage acted as a specific or indirectly as a Synergist to antibody formation cannot be stated.

Thus, no proof of explicitly phage-mediated efficacy, no proof that the condition would not have spontaneously reversed on its own, and no controls, but instead a remarkable result, with an indication as well of reason for caution regarding potential immunological reactions perhaps associated with the lack of formulation purification. Interesting indeed!

A Quote or Two from Hoeflmayr (1963): “Inhalation Therapy Using Bacteriophages in Therapy-Resistant Infections”

Stephen T. Abedon

Department of Microbiology – The Ohio State University

phage.org – phage-therapy.org – biologyaspoetry.org


I just came across this “report”, which can be found here:


This dates from 1963, I believe as a translation, and the full citation is “Inhalation Therapy Using Bacteriophages in Therapy-Resistant Infections”. Fortschritte der Biologischen Aerosol-Forschung-Jahren 1957-1961 (Progress of the Biological Aerosol Research-Years 1957-1961), pp. 403-409. See under “Further reading” for what presumably is the original and/or complete citation.

At any rate, this paper/chapter/publication/translation/report has some interesting passages.

In view of the growing resistance against antibiotics, it is vitally important that we try to find ways to counteract this development. … Farsighted clinicians warned us as long as 10 years ago, when we were still students, that we should not hastily treat any little infection with penicillin.
If we should discover any-new possibilities for treating infections, then we should look at these possibilities only from the angle that such a therapy would have to preclude the formation of resistance as much as possible, therapy with bacteriophages fills the requirement. The fact that this therapy has so far met with skepticism is due to the results which, until a few years ago, did not ome up to expectations
[Schaefer, W., “Contribution on Epidemic Control” Vol. 3, Hippocrates, Stuttgart, 1948]. If we try to track down the reason for the failure of the earlier bacteriophage therapy, we will find that this was mostly due to the biological properties of the phages.
Now it is important to know that the bacteriophage has high specificity. Therefore, therapy can be effective
only If the administered phage encounters its homologous bacterium.
The disadvantage of our earlier phage preparations was to be found not only in the inadequate breeding methods but above all in the fact that only about 1-2 phage strains were available. If we consider the large number of pathogenic bacteria strains, which play a role even in a very simple infection or which at least at times might play a role, then we would have to set up two requirements. First of all, in order to have a wide range of effectiveness, such a therapeutic substance would have to contain a large number of various phage strains. Second, it is necessary that phages which would come into consideration for therapy should have sufficient virulence with regard to pathogenic viruses.
We used the preparation (Diriphagen ® Dr. Heinz Haury Chemical Plant, Munich) because we believed that this preparation met the requirements we just set up. According to Information received, this reparation contains 180-200 different phage strains and thus has a broad spectrum of effectiveness. In addition, it also contains so-called aimed antimicrobics which act against those bacteria that reveal primary phage resistance. We might note here that both the phage components and the added microbics in every ampule are standardized and meet the requirements for biological standardisation as regards phage effect [Penso, G., and Ortali, V., Arch. belges Med. Soc., 1, 1959]. If we mention the two therapeutic components, that is the bacteriphages and aimed (directed) antimicrobics, we are really not fully describing the effects mechanism as such. We have a third factor here. What we are dealing with here is the stimulation of the inherent defenses of the body which are bound to be aroused and which are based on the following: In breeding phages and antimicrobics, the pathogenic microbes used for this purpose give rise to lysates. But these lysates are not eliminated; instead they are also fed into the body. They act like antigens and lead to the formation of antibodies which in turn are specifically directed against the bacteria to which lyntes were added [Glauser, H. A., Med. achr., 13, 420, 1959.]. This reaction requires a latency period of about 8-10 days. The value of this antibody formation is hard to estimate in the individual case. We can get some specific figures on this only if we determine the phagocytosis capability; but this must be done in the clinic. Any new therapy is very often impaired by the fact that we do not employ it until other, more familiar measures have failed. We must admlt that we did not use Deriphagen until we had some patients in whom other preparations had not produced success. This is further by reports from other authors who achieved surprisingly good results with this preparation [Cevey, M., Schweiz. Z. Tuberk. (Swiss Tuberculosis Joural),
15, 34, 1958; Corbelli, G., Bologna Med., 6, 57, 1959; Delacoste, P., Rev. suisse Med., August 1959; Schaefer, W., “Contribution on Epidemic Control” Vol. 3, Hippoprates, Stuttgart, 1948].

Figure 1 shows the result of our treatment. The first column shows the total number of all patients treated; then we have the number of patients cured which abounted to 55.1%; then we cow to those who showed substantial improvement and on the right we have those patients who did not improve as a result of therapy [34.8%].

The author notes, however, that there is a discrepancy between microbiological and clinical results. That is, patients apparently reported a return to healthfulness but this did not coincide with elimination of pathogen, which the author seems to suggest is a consequence of phage- resistant forms not being pathogenic.

The text in the PDF then essentially fades away, though the main text of the paper continues on for two more pages!

Further reading:

Hoeflmayr, J. (1962). Inhalationstherapie mit Bakteriophagen bei therapieresistenten Infektionen [Inhalation Therapy with Bacteriophages for Treatment-Resistant Infections]. Fortschritte der biologischen Aerosol-Forschung in den Jahren 1957–1961 [Advances in Biological Aerosols Research in the Years 1957–1961].  403-409. 1962. (I believe this is the original reference)

Abedon, S. T., Kuhl, S., Blasdel, R., Kutter, E. M. (2011). Phage Treatment of Human Infections. Bacteriophage 1(2): 66-85. [PubMed link] (this article provides further historical context on European use of phage therapy, though note that description of a German tradition in that article is completely lacking and so far as I am aware was unknown to the authors at the time of its writing)

Bacteriophages, Spatial Structure, and the Joys and Limitations of a Swiss Pass

Stephen T. Abedon

Department of Microbiology – The Ohio State University

phage.org – phage-therapy.org – biologyaspoetry.org

(This essay was written while touring Switzerland by train, July, 2014)


Travel can be joyous but also can involve a lot of work. The basic premise of travel is movement, whether specifically from one destination to another or instead something more random. In either case it takes time for you to move from that one place to another. Even the exploration of a smallish country therefore can take enormous amounts of time, since each of numerous legs of your journey will take some amount of time to traverse. You can purchase a Swiss Pass, and explore much of Switzerland over days and even weeks. You’ll see a lot, but you certainly will see far from everything. These temporal delays that are manifest as you travel are one of things that makes traveling difficult, but at the same time this relative slowness can be what makes a journey worthwhile. If you flittered from place to place at the speed of light, never pausing, you would touch upon much more, but your experience would be far different. Indeed, there are qualitative differences between your experiences as you fly, drive, take a train, ride a motorcycle, ride a bike, walk, or indeed not move at all.

Spatial structure is a property of environments in which delays in movement exist. If you can instantaneously and randomly be anywhere, then there is no spatial structure. In microbiology, spatial structure is seen especially under circumstances that do not substantially involve turbulent flow. When you shake a broth-filled flask, one of the consequences of that action is to reduce spatial structure. In terms of interactions between predators and prey, of bacteriophages and bacteria, the result is that any one individual may interact with any other individual with equivalent probability. If you replace any collision between phages and bacteria with the special kind of interaction that is sex, then you have random mating. If you replace any collision with the special kind of interaction that is phage infection of bacteria, then you have random infection. Either case is implicitly a consequence of a lack of spatial structure in the environment.

Spatial structure generally is what happens within environments almost no matter what. You can strive to remove spatial structure, such as via the shaking or stirring of broth, but absent such measures, or indeed if volumes are large enough and mixing slow enough, then some spatial structure nonetheless will be retained. A static microcosm – where the mixing of broth is reduced essentially to zero and therefore where movement is dominated by either motility or diffusion – thus can represent a spatially structured environment. More obvious is the spatial structure that occurs when movement is reduced even further, as is the case with the addition to environments of various thickening agents such as agar.

In phage biology the classic laboratory-observed consequence of spatial structure is the formation of phage plaques, which are clearings within otherwise turbid bacterial cultures, ones that have been spread or poured onto agar plates. The formation of a plaque requires three processes: phage population growth, phage-mediated reduction of bacterial densities, and, crucially, limitations in phage as well as bacterial movement.  Generally a plaque begins with a single plaque forming unit (PFU) which consists of an infective center and in turn can be either an individual phage virion, a clump of phage virions, a phage-infected bacterium, or a clump of bacteria at least one of which is phage infected. This infective center serves as a point source for the outward but nonetheless slow diffusion of phage virions away from their origin. The movement is outward only because the random process of diffusion tends to result in a broadening of the “cloud” of diffusing particles. Because of limitations on the rate of this movement, however, the cloud remains relatively small: the confluent lysis of an entire plate via the growth of a single plaque generally does not occur.

The phage is you. You can start a family and outfit each member of your family with a Swiss Pass. But unless your explorations of the amazing beauty that is Switzerland occurs over extremely long periods, then your and your family’s potential to see all of Switzerland will be relatively limited. This is less true, however, if your family is very large, so large that at least one family member is present to explore each place that may be explored. In this case complete exploration of a discrete area may be achieved. Your ability to explore broader areas nevertheless will be limited at least in part by how long it takes you or your family to get there.

Further reading:

Abedon, S. T., Bartom, E. (2013). Plaques. Brenner’s Encyclopedia of Genetics. Maloy, S., Hughes, K. (eds). Academic Press, pp. 357-357.

Abedon, S. T., Yin, J. (2009). Bacteriophage Plaques: Theory and Analysis. Methods in Molecular Biology 501:161-174. [PubMed link]

Abedon, S. T., Yin, J. (2008). Impact of Spatial Structure on Phage Population Growth. In: Bacteriophage Ecology, Abedon, S. T. (ed), Cambridge University Press, Cambridge, pp. 94-113.

For videos of my explorations of Switzerland, as well as other aspects of my existence, see youtube.com/channel/UCf0uLeBfCToHT3eAoYFmcNA.