Indian J Ped;at 48 : 37-40, 1981

Epidemioiogy of a cute respiratory disease in North India I.C. Verma, M.R.C.P., D.C.li., and P.S.N. Menon, M.D. Acute respiratory disease is a major cause of morbidity and mortality. Epidemiologic studies on acute respiratory disease in north India are summarised. Research needs in respiratory disorders are highlighted. Key w o r d s : A c u t e respiratory disease; Epidemiology of acute respiratory disease; Research needs in acute respiratory disease Acute respiratory infections are the leading causes o f morbidity and mortality in India in the pediatric age group. About 30% of the morbidity (range 2 7 40%) is accounted for by upper respiratory tract infection, t-a while 20-24% of deaths are due to lower respiratory tract infections. 4

Epidemiological factors Data from four prospective studies from north India are summarised, z'5'e'7 The study populations are listed in Table 1. (a) Attack rates of respiratory illness. Vasudeva observed 0.26 respiratory iUnesses per person per year. This low figure was because of under-reporting and exclusion of months o f maximum incidence (winter) from the study, s Gulati 2 obtained attack rate of 0.72, while N. Gulati 8 in a more recent study reported attack rate of 4.1 and 2.2 illnesses per person per year in children less than 5 years of age. In a study of rural populaFrom the Department of Pediat[ics, All India institute of Medical Sciences, New Delhi. Reprint request : Dr. I.C. Verma, Associate Professor in Pediatrics

tion in Punjab the attack rate was 2.5 episodes per person per year. These can be compared with figures per person per year from the West of 6 i n USA, 3 i n Scotland and 6-7 in England. s'6's Another prospective study of a birth cohort in a community in South Delhi involving 1326 newborns revealed that upto I year of age 9.6% of infants suffered from an exanthem like measles, 3.5% from whooping cough and 9.4% from discharging e a r s 9 This highlights the tremendous morbidity due to respiratory disorders. (b) Age group. The maximum incidence has been recorded in children less than I year in age. The incidence decreases with advancing age, presumably due to the immunity acquired after repeated exposures (Table IlL There is a sharp rise at school entry, declining to adolesence. (c) Seasonal variation. Table lII shows the expected increase in the incidence of respiratory disease during the winter months. In a study in Dyalpur, Haryana maximum episodes occured during December-February.

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Vol. 48, No. 390

THE INDIAN JOURNAL OF PEDIATIRlC$

Table I. Population Studied Author

Vasudeva

Gulati' Gulati s Gupta & Walia

Year of study

No of persons

Followup period

1962 1964 1973 1976

2,366 663 217 120

6 mo 1 yr I yr 1 yr

Table II.

Age in years : Vasudeva Gulati Gulati

LSE group* HSE group

Area

AIIMS campus, N e w Delhi. Masjid Moth, N e w Delhi. Malvianagar, New Delhi. Ropar, Punjab.

Attack Rates Per 1000 Person Months

0-1

1-2

2-3

3-4

4-5

51 81 408 216

41 67 368

24 66 291

31 56 304

48 31 327

200

198

155

126

* LSE--Low socioeconomic group, HSE--high socioeconomic group. The seasonal incidence does get modified by the occurrence of epidemics e.g. Vasudeva observed an epidemie o f parainfluenza in May, influenza A 2 in August and September, a n d respiratory syncitiai virus in S e p t e m b e r : (d) Socio-economic status. The effect of socioeconomic status is clearly evident in the study o f Gulati (Tables II & I I I ) . Vasudeva observed the highest incidence among sweepers. Next in frequency were doctors and technicians. This was due to the greater exposure due to their occupation. This study was conducted in families of individuals working in a medical institution. (e) Introduction of infection. Vasudeva noted that preschool children were responsible for introducing maximum infections, followed by father and least by the m o t h e r :

(f) lntrafamilial spread occurred maximally among preschool children. However the mothers suffered more proportionately. 5 (g) Correlation with over- crowding. A positive correlation with overcrowding was obtained by Vasudeva. Gupta documented that larger the family greater was the attack rate.l~ (h) Incubation period of respiratory illness observed by Vasudeva was a mean o f 3.3 days with a range of 1-8 days. The average duration of illness was 4.8 days with the individual being sick for 5-6 days. Gulati reported that average duration of respiratory episode was 5.7 days in the lower socio-economic group as compared with 5.4 days in the higher socio-economic group. 6

I.C. VERMA AND P.S.N. MENON : EPIDEMIOLOGY OF RESPIRATORY DISEASE Table III.

Seasonal Incidence per 100 Person M o n t h s

Spring

Gulati I GulatP LSE grp HSE s r p

Summer

59 22 c--- --',- ----~ 263 68

Autumn

Winter

60

124

205 120

564 359

Suggestions for future research Respiratory infections often overlap anatomic involvement. However based on the site of involvement a reasonable diagnosis and therapeutic plan can be worked out. A precise definition of diagnostic labels is clearly necessary not only for discussion among research workers but also for teaching primary health workers regarding management of these disorders. The interaction between malnutrition and infection is wellknown. Respiratory infections, even those of the upper respiratory tract, worsen the nutritional status by reduced intake of food during the episode and nasal obstruction interfering with breast feeding. Evidence that malnutrition predisposes to lower respiratory tract infection is overwhelming. However the relationship of upper respiratory in

tract infection to varying degrees of malnutrition is not worked out. Thus epidemiological studies to analyse the correlation of incidence and severity of respitatory tract infections to various grades of malnutrition are required. The association of respiratory infections with low environmental temperature is a commonly held belief. Is it due to the temperature per se or is it due the tendency for the population to live

39

indoors, and reduced ventilation during the cold season increasing the opportunity for spread of infection ? An investigation of attack rates in various parts of the country could provide useful data.

Dietary and cultural practices. There is a general feeling in India that certain "cold' foods predispose to upper respiratory tract infections. Although such associations are difficult to evaluate, there is a need to examine these associations in a scientific manner. In South India there is a common practice of blowing the oil through the nose of an infant to 'clear his air passages'. This often leads to lipoid pneumonia. Community studies to evaluate the effect of this practice are required. Etiologichl diagnosis of infection in the lower respiratory tract is difficult to establish, and the bacterial flora in the easily accessible sites like the nose and throat may not represent the true etiological agent in the more distant sites. Etiological information on infections of the upper and lower respiratory tract is inadequate. With the availability of microbiological techniques like countercurrent immunoelectrophoresis and enzyme linked iramunosorbent assay, there is a need to determine the etiological agent at the community level. This would help us to plan appropriate therapy. Clear guidelines for the peripheral workers on the use and dosage of antibiotics in these cases need to be worked out. There is a need to investigate the usefulness of the traditional systems of medicines in respiratory infections. The vaccines against pneumoeocci have been developed and since pneumococci are the commonest cause of pneu-

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THE INDIAN JOUKNAL OF PEt)IATRIC,q

Vo], 48, N o . 390

m o n i a , a clinical trial o n the usefulress o f this a n d other bacterial vaccines in high risk groups w o u l d be worthwhile.

5.

Vasudeva YL:Study of factors influencting acute respiratory tract infections. The~is Submitted to the Faculty of All India Institute of Medical Sciences for M.D. 1963

References

6.

Gulati N : Morbidity among Children of Different Sc~io-economic Groups. Thesis Submitted to the Faculty of All India Institute of Medical Sciences for M,D. 1973

1.

Verma IC, Kumar S : Causes of morbidity in children attending a primary health centre. Indian J Pediat 35 : 543, 1968 7. 2. Gulati PV : Morbidity and mortality pattern in children under five. Thesis Submitted to the Faculty of All India Institute of Medi8. cal Sciences for M.D. 1965 3. Chandra P, Venkat.a swamy G : Health and 9. nutritional status of preschool children in rural Tamil nadu. Indian Pediatr 15 : 499, 1978 4. Pocket Book of Health Stadslics in India, Centrsl Bureau of Health Intelligence, 10. Directorate General of Health Services, Ministry of Health & Family Welfare, Govt. of India, New Delhi, 1980. p 124

Gupta KB, Walia BNS : Longitudinal study of morbidity in a rural area in Punjab. Indian J Pediat 47 : 297, 1980 Verma IC : Upper respiratory tract infections. Indian J Pcdiatr 36 : 130, 1969 Hooja V, Madhavan S, Ahmed S.H, Ghosh S : Outcome and survival or a birth cohort in a community of South Delhi, Indian Pediatr 9 : 495, 1972 Gupta S : A c u t e respiratory viral infections-clinical aspects. Thesis Submitted to the Faculty of the All India Institute of Medical Sciences for M.D,, 1963

First aid for cobra bites Tt~e m o v e m e n t o f v e n o m f r o m the injection site was s t u d i e d by m o n i t o r i n g p l a s m a levels using r a d i o i m m u n o a s s a y o f v e n o m in conscious m o n k e y s . The movem e n t was effectively delayed by the applic a t i o n o f a firm crepe or elastic b a n d a g e over the whole limb, a n d especially the injection site, c o m b i n e d with its i m m o b i l i -

sation by a splint. Pressure a l o n e or i m m o b i l i s a t i o n a l o n e did n o t delay v e n o m movement.

Abstracted by I C. Verma

From S.K. Sutherland et al: Indian J Meal Res 73 : 266, 19110