PREVALENCE OF STREPTOCOCCAL PYODERMA IN RELATION TO CLIMATE AND HYGIENE

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PREVALENCE OF STREPTOCOCCAL PYODERMA IN RELATION TO CLIMATE AND HYGIENE DAVID TAPLIN

LYLE LANSDELL

Departments of Epidemiology and Public Health and Dermatology, University of Miami School of Medicine, Florida 33152, U.S.A. ALFRED M. ALLEN Division of Preventive Medicine, Walter Reed Army Institute of Research, Washington, D.C. 20012, U.S.A.

RAFAEL RODRIGUEZ Centre

Dermatologico

Federico Lleras Acrosta de Bogota, Colombia

ALONSO CORTES

Department of Internal Medicine (Dermatology), University of Antioquia Medical School, Medellin, Colombia Skin infections in Colombia were studied over one month to determine the effect of climate on the prevalence and flora of bacterial pyoderma, and to acquire first-hand information on cutaneous infections of military importance in tropical Latin America. The survey involved nearly 1500 people (children and soldiers) living in four ecological zones, ranging from the cool climate of Bogota to a jungle environment. Prevalence of pyoderma and rates of recovery of bacterial pathogens were highest in the jungle, intermediate in the temperate zone, and lowest in the cool climate. The level of hygiene was the principal determinant of prevalence within each climatic zone. Streptococcus pyogenes was recovered from 82% and Staphylococcus aureus from 76% of all lesions cultured. Soldiers in the jungle had the highest prevalence of pyoderma (38%), whereas those in the dry tropics (savanna) had a low prevalence of pyoderma. Summary

Introduction

INTEREST in group-A Streptococcus pyogenes as a cause of common infections of the skin has increased since the recognition of the relation between skin strains of streptococci and acute glomerulonephritis (A.G.N.), and the development of more sophisticated methods of laboratory typing.i The lack of accurate prevalence data, differences in bacteriological isolation techniques, socioeconomic and ethnic differences in populations studied, and climatic variations make it difficult to compare different published reports or to separate the effects of 7802

10

March 1973

different levels of hygiene and living conditions within a population. We have attempted to determine the role of some of these variables by a survey of pyoderma in three populations of children in which levels of hygiene, ethnic background, sex, and climatological environmental stresses were defined using standardised clinical criteria and bacteriological methods. Colombia was ideal for such a study because of the diversity of climate and terrain within short distances, the relative ethnic homogeneity of the people, the presence of sizable underprivileged populations in which a high prevalence of infection might be expected, and the cooperation of professional colleagues and government agencies. Military and civilian populations were available for study. Methods Total-body examinations were made of all subjects in the study by A. M. A., and all skin defects which showed any evidence of infection were recorded on a body diagram sheet. After removal of crusts or debris, each lesion was cultured using a calcium-alginate swab. The exudate was inoculated on double-layer plates of trypticase-soy agar (T.S.A.) containing 1 f-lg. per ml. ’Bacto-crystal Violet’ (Difco) overlaid with T.S.A. containing 1 f-lg. per ml. crystal violet and 6% sterile defibrinated sheep blood. Staphylococcus aureus was isolated from lesions on nutrient agar

(Baltimore Biological Laboratory) containing 4% cycloheximide and 75 {jLg. per ml. polymyxin B.2 Plates were incubated aerobically for twenty-four hours at 37 °C, and negative plates were incubated for a further twenty-four hours. Fresh media, refrigerated in storage before use and transported to the field in insulated containers, were used throughout the study. Group-A streptococci were identified by colonial morphology, hxmolysis, gram stains, and bacitracin sensitivity, and Staph. aureus was identified by colonial morphology, gram stains, and tube coagulase tests. The standard of hygiene was evaluated by inspecting the children and their clothing, visiting their homes and living quarters, inspecting the facilities of the institution under study, and by discussions with teachers and supervisors. Study populations were surveyed during September, 1971, and were composed of children from the lower socioeconomic classes living in three climatic zones, cool, temperate, and tropical (all humid), and soldiers living in a humid tropical (jungle) or dry tropical (savanna) environment.

The four areas provided a wide range of altitude and climate, with consequent variation in living habits, vegetation, and insect life. The principal features of each were as follows: Bogota-capital city, population million, altitude 8700 ft. (2600 m.), dry-moist lower montane forest (Holdridge’s classification); Medellinsecond largest city, population 1-2 million, altitude 5000 ft. (1500 m.), moist subtropical forest; Tolemaida-home of Tenth Brigade, Colombian Army, near town of Melgar in Magdalena River Valley, altitude 3000 ft. (900 m.), dry

location 2-5

502

tropical; Apartado-frontier town carved out of jungle for commercial exploitation (bananas, cocoa, lumber), population 5000,

at

sea-level

near

Gulf of Uraba, moist tropical.

Results

1269 children and 213 soldiers were surveyed; 199 (12-6%) had pyoderma lesions which were cultured. Among the children, the prevalence of pyoderma and recovery of streptococci and staphylococci from lesions varied according to climate. Prevalence and recovery-rates were highest in the tropics, intermediate in the temperate zone, and lowest in the cool region (table I). The standard of hygiene was another TABLE I-PREVALENCE OF PYODERMA AND RATE OF RECOVERY OF STREP. PYOGENES AND STAPH. AUREUS FROM COLOMBIAN CHILDREN IN DIFFERENT CLIMATES

(SEPTEMBER, 1971)

Prevalence of pyoderma during September, 1971, in lower socioeconomic class Colombian children in relation to altitude (climate) and level of hygiene.

in

significant variable; within climatic zones differences hygiene appeared to be the principal determinant pyoderma prevalence (table 11 and accompanying figure). P-haemolytic streptococci were recovered from 82% of all lesions cultured, and from approximately 95% of any purulent lesions. Skin lesions which yielded streptococci included typical ecthyma, infected insect bites, erosive intertrigo behind the ears, infected lacerations, and impetigo of the scalp and face. It would not be far wrong to suggest that virtually any purulent lesion could be considered streptococcal. Staphylococci were also recovered in a high proportion of cases (76%)-nearly always in association with streptococci. The highest prevalence of pyoderma was found in a military unit which had just returned from a twenty38% five-day jungle operation near Apartado. on the of the soldiers had chiefly pyoderma, (14/30) extremities. In contrast, only 3% (4/130) of infantrymen engaged in conducting two-three-day operations

in of

TABLE II-PREVALENCE OF PYODERMA AND

*

a dry tropical area near Tolemaida (savanna and dry forest) had pyoderma, and this prevalence was essentially no different from that of troops in garrison, of which 5°6°0 (3/54) had pyoderma. Insects were seen feeding on exudate from the lesions only in the humid tropical area. Large numbers of Hippelates eye gnats were seen feeding on lesions in

soldiers and occasional houseflies in children.

were seen on

lesions

Non-suppurative Complications of Streptococcal Infection Attempts were made to determine the frequency of acute glomerulonephritis (A.G.N.) and acute rheumatic fever (A.R.F.) in Colombian populations. Poediatricians and nephrologists in Bogota and in Medellin were questioned as to the amount of each disease seen. In addition, visits were made to two hospitals in Bogota to see if attending physicians or hospital records could provide pertinent information. The impression was that A.G.N. and A.R.F. were both common, and that A.G.N. was probably significantly more common at lower altitudes (warmer climates) AGE, SEX, CLIMATE,

AND LEVEL OF HYGIENE

Negroes only (all other populations racially heterogeneous, consisting of mixtures of Amerindians, Caucasians,

and

Negroes).

503

than A.R.F., although data were not available for defined populations. Data from official sources indicate that A.G.N. and A.R.F. are almost equally common in Colombia (table III), but these data are probably not complete. TABLE III-COLOMBIAN MEDICAL

yielded this pathogen, which indicates efficiency of colonisation. This degree

a

of

high infectivity

very

in the absence of a detectable carrier state on normal skin is difficult to explain except on the basis of highly efficient insect vectors, although in family units spread by contact probably also plays an important role.

STATISTICS*

hosts in Colombia for their help with these Dr Rocio Arango, Dr Guillermo Arboleda, Dr Gonzalo Calle, Colonel Hernando Latorre, Dr Fabio Londono, Major Carlos Monsalve, Miss Amparo Motta, Major Cicer Noriega, Major Padilla, and Dr Angela Restrepo. This investigation was supported by U.S. Army Medical Research and Development Command and the Commission on Cutaneous Diseases of the Armed Forces Epidemiological Board contract DADA 17-71-C-1084. We thank

our

studies, especially

17-5 million (1964 census). Annual statistical reports of the Colombian National Administrative Department of Statistics.

Population:

Requests for reprints should be addressed to D. T., Departof Epidemiology and Public Health, University of Miami School of Medicine, P.O. Box 875, Biscayne Annex, Florida

ment

33152, U.S.A. Discussion

In both the civilian and the military groups, we were able to account for all individuals at risk, so that our data represent the true prevalence of disease. The standard of hygiene was evaluated when the subjects were examined, without knowledge of the culture results. Each member of the team performed the same duties at each survey site, and the laboratory work was also conducted by the same individuals throughout. The same batches of media were used for all cultures. We therefore believe that the differences between the populations represent the effects of climate and hygiene. We believe that the higher prevalence of pyoderma in the hot-moist environment at Apartado reflects the greater frequency of insect bites and perhaps the presence of wound-feeding flies which were not present at the higher altitudes. Hippelates eye gnats have been strongly implicated as a vector of staphylococci and streptococci in populations with a high prevalence of skin infection.3.4 We cannot explain the higher recovery-rates of both Strep. pyogenes and Staph. aureus (table i) from Our bacteriological lesions in the hotter climate. methods were identical and the plates were incubated at 370C throughout the study. These pathogens must be more abundant or more easily recovered in hotter

climates. There was an almost linear relation between prevalence of clinical disease and altitude (environmental temperature); and hygiene had an obvious effect at all altitudes. This kind of data could be important in health-care planning or preventive medicine. The experience with the Colombian Army units was remarkably similar to our findings in Vietnam.55 Men exposed to combat conditions, insect bites, and in the tropics are likely to develop pyoderma, and the pathogen is likely to be Strep. pyogenes. We have not recovered streptococci from normal skin in healthy populations, although we did recover them from the perineum, nares, and fingernails of about 25 % of men who had active lesions in Vietnam. In our studies in Vietnam,5 Florida,Haiti, Uganda,’7 and the tropical areas of Colombia we consistently obtained a high recovery of group-A streptococci from purulent skin lesions. Over 90% of the lesions

trauma

REFERENCES

Wannamaker, L. W. New Engl. J. Med. 1970, 282, 23, 78. Finegold, S. M., Sweeney, E. E. J. Bact. 1961, 81, 636. Taplin, D., Zaias, N., Rebell, G. Devs ind. Microbiol. 1967, 8, 3. 4. Bassett, D. C. J. Trans. R. Soc. trop. Med. Hyg. 1970, 64, 138. 5. Allen, A. M., Taplin, D., Twigg, L. Archs Derm. 1971, 104, 271. 6. Kelly, C., Taplin, D., Allen, A. M. ibid. 1971, 103, 306. 7. Nsanzumuhire, H., Taplin, D., Lansdell, L. E. Afr. med. J. 1972, 49, 1. 2. 3.

84.

FENFLURAMINE IN THE TREATMENT OF OBESITY KARL RICKELS PETER HESBACHER

ALBERT STUNKARD

Department of Psychiatry, University of Pennsylvania, and Philadelphia General Hospital, Philadelphia, Pennsylvania, U.S.A. Summary

double-blind,

90 obese women taking fenfluramine for seven weeks were studied. This between-patient study, the first to

compare fenfluramine with

an

amphetamine,

was

carried out by six general physicians. Fenfluramine and dexamphetamine treatment produced similar weight-losses and had similar drop-out rates. Each drug produced a greater weight-loss and had a lower drop-out rate than did a placebo. Both drugs resulted in modest decreases in emotional symptoms, but fenfluramine produced more side-effects. Introduction

CURRENT restrictions on the use of amphetamines for the treatment of obesity in the United States aroused our interest in fenfluramine, which, in the ten years since its introduction, has become the drug most widely used in Europe against obesity. This widespread usage has occurred despite a surprising paucity of data about the drug’s efficacy. Most of the reported clinical trials have compared fenfluramine only with a placebo,1-7 a comparison which favours fenfluramine. The three comparisons with active agents have produced equivocal results. One showed fenfluramine to be more effective than metformin in nondiabetics,while two studies comparing fenfluramine