|Year : 1970 | Volume
| Issue : 1 | Page : 17-22
Flies and mothers as modes of transmission of trachoma and associated bacterial conjunctivitis
CK Gupta, UC Gupta
National Trachoma Control Programme, India
C K Gupta
National Trachoma Control Programme
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Gupta C K, Gupta U C. Flies and mothers as modes of transmission of trachoma and associated bacterial conjunctivitis. Indian J Ophthalmol 1970;18:17-22
|How to cite this URL:|
Gupta C K, Gupta U C. Flies and mothers as modes of transmission of trachoma and associated bacterial conjunctivitis. Indian J Ophthalmol [serial online] 1970 [cited 2020 Jul 7];18:17-22. Available from: http://www.ijo.in/text.asp?1970/18/1/17/35054
| Introduction|| |
Trachoma is widely prevalent in tropical and subtropical countries and has been recognised world over as a major cause of preventable blindness. Highly associated with secondary bacterial infection, it occurs in an endemic form in North Western states of India. Trachoma is a viral disease and its infection to the healthy eye is due to the transmission of the contaminated discharge from the diseased eyes which contains the trachoma virus. The extent of the problem of trachoma and associated bacterial conjunctivitis is attributed to various modes of transmission such as common flies, mothers, fomites etc. etc. which help in transmitting trachoma and associated bacterial infections. While many attempts have been made in order to assess the extent of the problem of trachoma and associated bacterial conjunctivitis, comparative study of these various modes has received less attention. In the present paper, however, an effort has been made to study the principal modes of transmission, with particular emphasis to that of common flies and mothers, and the individual roles they play in the dissemination of trachoma and associated bacterial infections.
| Materials and Methods|| |
For the analysis part of this paper, the data, pertaining to three surveys undertaken by Trachoma Control Pilot Project, India, has been dealt with, which are described as follows:
- General Systemic Survey, to study the epidemiology of trachoma and collection of data of various socioeconomic and ophthalmological details under two schedules (a) household and (b) individual.
- Repeated Monthly Survey, to determine the seasonal and natural effect of bacterial conjunctivitis in the severity of trachoma.
- Fly count in 3 villages, throughout the year.
Surveys I & 2 were conducted in the two blocks of Jawan Sikandarpur and Tappal, in the district of Aligarh, Uttar Pradesh.
For survey 1, the data was collected over 15,157 individuals from 4,105 households of the 29 villages of the area; whereas for survey 2, 5 of the 29 villages covering 2,801 individuals, were selected for examination regularly at monthly intervals. The age, sex, religion, means of livelihood, clinical picture of trachoma, bacterial conjunctivitis and results of conjunctival smear examinations were recorded.
During the repeated monthly survey 55 infants, free from trachoma, were examined each month with a view to seeing the seasonal variations in new infections.
For survey 3, in three of the five villages taken for Repeated Monthly Survey, a fly count was made throughout the year in order to find out quantitative and qualitative indices on fly population. The purpose of these counts was to study the association of the fly index with that of bacterial conjunctivitis. Scudder's Grill technique of fly collecting was adopted and the fly population was recorded at weekly intervals through out the year. Indices on fly population were thus calculated based on three weeks moving averages.
With a view to finding out whether there was any correlation between the indices on fly population and prevalence of bacterial conjunctivitis, co-efficient of correlation was worked out after transforming fly Indices to their logarithmic values and percent prevalence to their logits.
Significance of the difference of this co-efficient from `o' was tested through "t" test.
| Resuts|| |
The extenstive results of all the surveys mentioned above have been discussed in details in reports SEA/ TRACH/Part VIII 17th November, 1959 and SEA/TRACH/ 10-REV. 1, 30th June, 1961, but since this paper is based on the data collected during these studies, certain observations are repeated here.
Active Trachoma (Tr. I-III) was found to be in 22.6% of the total persons examined. The children of the age group 3-4 years were found to have the highest prevalence 72.7% (Graph-I). It was also observed that as the age advanced. beyond 4 years there was a decreasing trend in the prevalence of active trachoma and healed up trachoma (Tr. IV) was found to have assumed an upward trend. In early ages both males and females were almost equally affected from active trachoma but, after 10 years of age generally, the activity was found to have been retained more among females as compared to males [Table - 1].
Practically no significant seasonal variations in prevalence of trachoma (active) were noted throughout the year during the Studies of Repeated monthly survey, but in 55 trachoma free infants it was observed that 20 were infected during one year. Out of these 20, 18 were infected during the peak period of conjunctivitis [Table - 2]. In the secondary bacterial infections it was observed that the prevalence of subacute and acute conjunctivitis was highest during the two peak periods of the year i.e. April-May and August-September [Table - 2] and further it was seen that it was mostly prevalent among children upto 10 years of age.
Observations on fly indices disclosed that the highest peak of the fly population occurred in early summer i.e. in the first fortnight of MarchApril and second peak was found to be in the middle of August [Table - 2].
The correlation co-efficient was worked out to be 0.648 which was significantly different from 0. (t=2.687; 0.02 < P < 0.05).
| Discussions|| |
The figures obtained during General Systematic Survey revealed that 22.6% of the total persons examined showed the clinical signs of Active Trachoma and that it was highly prevalent among the children of age group 0-9 years [Table - 1]. It was further observed that as the age advanced active trachoma had a decreasing trend. Existence of active trachoma in the very first year of life clearly indicates that the children, of even months of age, could also contract trachoma and secondary bacterial infections. There are multiple factors which play important role in the transmission of infection. Singh and Dewan  have stated that by raising the standards of living and personal hygine of masses, trachoma could, to a considerable amount, be controlled. The results of General Systematic Survey supported this statement, as it was observed that some of the factors influencing the high incidence of trachoma and bacterial infections were illiteracy, poverty, low standards of personal hygiene and environmental sanitation. Persons, who were exposed to smoke, such as females had more trachoma as compared to others. Using the same end of saree or dhoti or use of common towel to wipe faces was also found to have contributed to the transmission of infection. Tendency of children sleeping together on the same bed was also observed to be one of the factors contributing to the mode of transmission.
The factors discussed above are those which certainly help in transmitting trachoma and other bacterial infections, making the latter major public health problems. But in addition to these there are factors which also contribute to the pool of transmitting agencies to a substantial amount. Trachoma infection can be transmitted to children through their mothers either by direct contacts or fomites. The common fly can also be one of the important means of communication for the infection from eye to eye and thus adding more to the trachoma problem. Wilson, following new born 50 children showed that all the children had active signs of trachoma at the end of the year. In agreement to this Maxwell Lyons  has stated that it was a common belief that in countries, where trachoma is endemic, the children catch the infection through their mothers. The data in General Systematic Survey disclosed that the activity of infection was more in females as compared to males and thus the children could have caught the infection through their mothers but at the same time it may be stated here that this might not have been the only mode of transmission of infection to the children. It might also be presumed that the signs of active trachoma retained longer among females of higher age groups because they remained more in contact with their infected children and were exposed to become reinfected. This point is, however, worth while to note and needs further elucidations.
Age morbidity-line chart (Graph-1) shows that in the very first year of life, when the child remained mostly in the arms of its mother, only 24.4% of the children of that age groups were found with clinical signs of active trachoma, though at this age too they were exposed to other modes of transmission of infection. As the age advanced the infant's contact with mothers started decreasing and they were left more to themselves and as such more exposed to the other modes of transmission. Had all the children acquired trachoma virus through the contacts with their mothers, there should have been more or less 100 percent incidence of active trachoma among the children of age 0-1 or 1-2. But on the contrary the highest prevalence (72.7%) was observed among the children of 3-4 years of age and this is the age group which is attended by their mothers only for feeding but are free to move about and play. At this age they are neither conscious nor capable of keeping themselves free from flies. The new infections, to trachoma free infants, had also mostly occured during the peak period of conjunctivitis preceded by peak periods of fly prevalence [Table - 2]. This leads us to infer that mothers, though play a definite and substantial role in disseminating trachoma infection are not the main cause which contributes to the problem. Considering fly to be the next main factor influencing the high incidence of trachoma and bacterial conjunctivitis it was observed [Table - 2] that indices on fly population were high in the two peak periods of March.-April and August-September and more or less in the same two durations the bacterial conjunctivitis was found to be having inflating tendency. Dr. Maxwell Lyons in agreement to the results of investigations carrid out by Wilson (1935-1936), also feels that the trachoma infection was carried out from eye to eye along with bacterial infection; and flies, probably, play the most important role in the dissemination of these infections. Correlation co-efficient (0.648) which was significantly different from 0, also provided evidence that the prevalence of secondary bacterial conjunctivitis was, probably, positively associated with the inflation of common fly during the year. Maxwell Lyons and Abdin  had also tried to establish a definite and positive association between seasonal epidemics of bacterial conjunctivitis and the fly population, which is in perfect agreement to our own inferences concluded before. Further the highest prevalence was found at the age of 3-4 years (72.7%), which gives an indication that the children of that age group, which was, probably, more likely to be exposed to fly, contract infection from flies than catching the infection through their mothers. Thus it can be said that the high incidence of trachoma and associated bacterial infection can, perhaps, be satisfactorily controlled by eleminating the common house fly and controlling the trachoma and or associated bacterial infection amongst the females of child bearing age groups.
| Summary|| |
The General Systematic Survey and Repeated Monthly Survey were carried out in the district of Aligarh to study the epidemiology and seasonal variations over the prevalence of trachoma and bacterial conjunctivitis.
Trachoma infection was detected as early as the first year of life and children suffered most at the age of 4.
Females beyond 9 years of age were found to have more active trachoma (Tr. I-III) as compared to males and this leads to the inference that they might be one of the sources contributing to the infection of Trachoma and associated conjunctivitis.
The indices on fly population during the year disclosed that the common house fly may be taken as one of the main contributory source of infection and it plays the significant role in disseminating the trachoma virus.
| References|| |
Duke-Elder, W. S.; Parson's Diseases of the Eye 13th edition n. 173 London. J. & A. Churchill Ltd., (1959).
Maxwell - Lyons, F.; The dual problem of Acute ophthalmia and Trachoma in Egypt WHO/Trachoma/20 October. 1951pp. 3 and 7.
Maxwell-Lyons, F and Abdin G. L.; The Effect of fly control on the epidemic spread of acute ophthalmia "Drs Maxwell Lyons and Gamal Eddine Abdin Bull. Oph. Soc : of Egypt Vol. XIV session 49-1952 pp. 81-87.
Satnam Singh hnd Dewan, H. R. Comparative theraputic Field Trial of Aureomycin in Oil, Aureomycin ointment and oral suiphamethocypyridazine (Lederkyn) against Trachoma in the states of Uttar Pradesh, North India. Revue Internationale du Trachome'-Extrait due volume No. 3, 1961, pp. 282.
[Figure - 1]
[Table - 1], [Table - 2]