|Year : 1960 | Volume
| Issue : 4 | Page : 104-106
|Date of Web Publication||5-May-2008|
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Cooper S N. Editorial. Indian J Ophthalmol 1960;8:104-6
A periodic summing up of our knowledge up-to-date is most essential in these days of progress progressing in geometrical progression and a summary of the reports to the International Organisation against Trachoma prepared for us by Dr. Rostkowski gives a concise clear picture of the position of our knowledge today. Even then there are a few points that need commenting especially when viewed from an Indian angle and Indian experiences.
Any doubt about the trachoma virus as the etiologic agent of trachoma seems to have been finally_ cleared. The accent of research has shifted to the cultivation of the virus, serological reactions and in-vitro experiments. This is going to make the study of trachoma more scientifically exact, but we hope not at the cost of clinical observations. Animal experiments, are not so contributory as experiments on human volunteers, but again one fears that observations on human patients are being pushed in the background. It is rather strange that some useful contribution to the literature on trachoma based on human patients by Indian Ophthalmologists has not caught the eye of the principal reporters.
However, in all these experiments and approaches and reports it is surprising that little account has been taken of contributory causes. The scourge of the trachoma virus is not due to the virus alone so much as virus with secondary infection. Secondary infections not only precipitate the trachomatous lesion but also determine its severity. In Egypt it is a primary gonococcal infection (not genital), and in India Koch-Week, B. pyocyaneous and other infections, which boost the trachoma lesion.
But there are other contributory causes. The nutritional status is such a great determining factor that Tulsidas in a noteworthy clinical study has made a distinction between trachoma of the rich and trachoma of the poor; it is only the latter variety which runs into the stage of distressing sequelae of severe cicatrization and entropion.
Cooper in his observations, has been impressed by the frequency of phlyctinular conjunctival condition associated with resistant forms of trachoma and has corraborated this observation by getting beneficial effect from tuberculin therapy in many such cases. In other words he is of the opinion that the conjunctival bed has to be prepared by some form of ''weakening'' agent, not necessarily tuberculin sensitivity as in his cases, so that the trachoma virus can have a foothold first and a further strangle-hold if the weakening agent is allowed to prevail.
Significance to these two observations is added by the observations of MacCallan, quoted in the Report, that a status lymphaticus and insufficient nourishment are contributory causes. But for the recording of these observations, they have not been pursued into their factual implications.
In his tour of Japan recently, the Editor was told of the marked drop in the incidence of trachoma in Japan. The Editor in his interest in the contributory value of tuberculin hypersensitivity asked Prof. Mitsui (Tokushima) about the incidence of tuberculosis in Japan and he remarked that it also had considerably dropped. To the Editor's query whether the lower incidence of trachoma cannot be attributed to a lower incidence of tuberculosis as a contributing or adjuvant factor Prof. Mitsui admitted the possibility. He suggested some interesting animal experiments in pursuit of this point.
Ursekar and Cooper in their approach to the geographical distribution of trachoma have pointed to the unequal distribution of trachoma in India and even to packets )f very low incidence in otherwise highly infected areas with similar living conditions. They have incriminated the prevailing winds.
The Editor in his recent tours of Africa and Japan ascertained that even in these countries the geographical distribution was uneven even in spite of the fact that living conditions were almost identical everywhere in the respective countries. This interesting geological factor has not been commented upon in the Report.
In contrast to these observations some conclusions which may be misunderstood have been mentioned; for example monkeys with vitamin deficiency are supposed to be less sensitive to trachoma infections. Be it noted, vitamin deficiency is not a protective factor. It is probably because of keratinization of the epithelium which prevents a foot-hold for the trachoma virus. What Tulsidas and Mac Callan imply by nutritional deficiency is a diet poor in proteins, which definitely is a contributory factor.
Another rather irresponsible conclusion that has found its way in the Report is "a relative resistance in the Negro (pigmented races) has been noted by some". India, being an almost equal admixture of the pigmented and less or non-pigmented races, presents no such difference. The Editor in his tour of East Africa was shown the worst cases possible of trachoma in the public hospital for the Negroes at Nairobi, so much so that on the day of his visit 13 cases were scheduled for entropion operation by Dr. Boas' unit and not a single case of cataract or glaucoma for operation was tabled.
In experiments on ihuman beings mere transfer of trachornatous material does not imitate the mode of infection under natural conditions. It is fortunate that this is so, because experiments on human beings would be fraught with greater danger if one or two contributory causes are added. Without the use of adjuvant factors. trachoma transfer to human conjunctiva will be amenable to treatment. Distinction must be made between trachoma of human beings and trachoma of human volunteers.
The same argument hold, in cases of animal experiments, where the infection is so mild that many times the H.P. bodies are not discovered at all. No experiments appear to have been carried out to boost the pathogenicity of the virus by adjuvants, by way of secondary infection, protein deficiency, or simultaneously induced hypersensitivity.
The finalization_ of the vital cycle of the virus its cultivation in-vitro, its proper classification and pathogenicity are clarifying and instructive. So also the fact that trachoma is a toxaemia capable of giving risk to complement fixation tests is an achievement of a very heartening nature. Similarly the study of Gall (Hungary) implicating the lacrimal passages in trachornatous infection is interesting. The clarilication of the diagnosis of trachoma from folliculosis, inclusion conjunctivitis, etc. again is of great clinical and practical value.
But on the clinical side a very doubtful statement is allowed to escape without clarification. "'Trachoma contracted in infancy tends to be milder than trachoma contracted in adult life". It is possible that trachoma contracted in adult life has greater chances of running into boosting factors like foci of infection, but those who have seen trachoma in North India, in its "Home," and who have appreciated the emphatic statements of Tulsidas will certainly disagree. Childhood is the age for contracting it and the severity of the disease is nothing to joke about.
As regards treatment while admitting the usefulness of sulfonamides and antibiotics, one wonders whether the advent of sulfonamides and antibiotics is the main cause in the decrease in incidence and severity of trachoma as reported, for the following reasons :
- Mass campaigns with the drugs coincided with mass educational and sanitary programmes, financed by Health Organisations.
- The possibility and more probable effectivity of these drugs acting on the secondary infections, mostly present in human trachoma.
- There has been no real agreement as to which antibiotic or sulfonamide is adjudged best against the virus.
- Antibiotics and sulfonamides are useless in chronic trachoma.
- No comparative study has been made of the modern drugs with older remedies, e.g. silver nitrate, under identical environmental educational and nutritional conditions.
- The trachoma virus having epitheliotropic properties, the desquamation of the conjunctiva with one application of 2 per cent silver nitrate solution or a strong solution of sulfonamides can sweep the conjunctive clean of the many viruses taking harbour within the epithelial cells. Even the disappearance of H.P. bodies with the use of antibiotics and sulfonamides quoted in the Report and their reappearance on discontinuing the same have been attributed to desquamation caused by the drugs.
- Inability of the sulfonamides to act on the virus isolated and developed in-vitro, as quoted in the Report.
Finally coming to the need for a formula to express incidence and severity of the disease to chart the waning of this scourge, a very useful point has been achieved percentage of trachoma in patients afflicted with eye diseases. This is exactly the way in which Ursekar ascertained the geographical distribution of trachoma in India, because this does away with the variable factor of transport facilities to be taken into account if we want the percentage per population. It gives a good idea of the amount of affliction; it does not give the actual percentage of affliction per population.
The actual figures for percentage trachoma per population is being worked out at the moment by the Trachoma Pilot Project of India, for the different parts of the country. The figures when completed will make interesting comparison with figures determined by Ursekar.
However this formula does not cover the degree of severity , unless each case is put into its degree category (TI,2,3,4). This would require an expert or at least a trained technician. Rostkowski's argument that incidence in conscripts is competent to express the degree does not appeal so much as the suggestion of Tulsidas, to take the figures for entropion operation to the number of trachoma cases, to express the degree of severity.
So with the data : (1) total hospital attendance, (2) total population, (3) total number of ocular afflictions, (4) total number of cases clinically diagnosed as trachoma, preferably confirmed by examination of epithelial scraping and (5) total number of entropion operations, let the statistician get busy with his sines, tangents, squares and square roots and work out an exacting formula to express the incidence-cum-severity of the disease, so as to make the study statistically significant.
After all that is said and clone, like most infections trachoma can only be subdued, it can never be conquered and kept conquered.
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