A tuberculin survey in the island of Montserrat, British West Indies

Brit. 07. Dis. Chest (I959) 53, 99.

A TUBERCULIN SURVEY IN THE ISLAND OF MONTSERRAT, BRITISH WEST INDIES BY RICHARD A. S. CORY From the Pan American Sanitary Bureau, Regional Office of the World Health Organisation, Washington INTRODUCTION

THIS survey was conducted on behalf of the Pan American Sanitary Bureau, Regional Office of the World Health Organisation for the Americas, between November 27 and December 6, I957, with the object of determining the needs of the island of Montserrat for a BCG mass campaign. Montserrat is a small, very mountainous West Indian island belonging to the group known as the Leeward Islands. With Antigua and St. Nevis it constitutes an inverted triangle, 32½ square miles in area, with Antigua about 27 miles to the north-east and St. Nevis 33 miles to the north-west. Geologically it is believed to be entirely volcanic. There are three groups of mountains of which those in the south rise to over 3,ooo feet. Between these and the mountains to the west there is a high saddle of land lying at about 1,2oo-I,5OO feet which is almost entirely given over to agriculture. Several hot sulphur springs bear witness to the volcanic origin of the island. Heavily wooded mountain slopes above 1,5oo feet explain the abundance of little streams. For a West Indian island the climate is unusually cool, and it is said that there is no indigenous malaria. Discovered by Columbus in 1493, the island was named by him after a mountain near Barcelona. It was first colonised by the English in 1632 , only to be captured by the French in 1664. Restored to England in 1668, it was largely populated by Irish in the next half-century, and today many of the names of the inhabitants are Irish. In 1782 it was again captured by the French, to be ceded back to England two years later. Since 1784 it has been a British colony, becoming recently a member of the West Indian Federation. The early European planters, who cultivated cotton and sugar cane, introduced slave labour as elsewhere in the West Indies, and today the population is almost entirely coloured, though there still remain a few white families and business men, probably under I per cent. of the total population. Sea Island cotton gradually took over from sugar cane, but in the middle of the nineteenth century the lime became an important product. This latter has now largely disappeared as a result of disease making its appearance among the trees. Today Montserrat produces only some cotton, sugar, rum and a certain amount of vegetables, which latter are largely marketed in the neighbouring island of Antigua. Financially it is a poor island, though a great number of the people-(Receivedfor publication September~7, 1958.)

I O0

CORY

particularly in the northern half--own and work their individual pieces of land. Plymouth, the capital town, with a population of about 4,ooo, is located on an open roadstead in the south-west. The overall population of the island is probably somewhat under z4,ooo. In the last few years some 3,ooo of the adults have emigrated to England in search of more remunerative work. How many of these will return--some with tuberculosis--is uncertain, but the homeward drift has not yet begun. [~'~

MAJOROISEASEAREAS

0

SCHOOLSTESTED

A

SCHOOLSNOTTESTED

CAVALLA HILL TOTALENROLLMENT TESTED COMPLETEDTEST NEGATIVE DOUBTFUL POSITIVE

SL JOHN'S 218 190 178 78% 8% 14%

I

TOTALENROLLMENT 237 TESTED 210 COMPLETEDTEST 205 NEGATIVE 76% DOUBTFUL 16% POSITIVE 8%

t

TOTAL ENROLLMENT TESTED COMPLETEDTEST NEGATIVE DOUBTFIJ, L POSITIVE

220 154 146 63% i t2% 25%

CATHOLIC TOTALENROLLMENT TESTED COMPLETEDTEST NEGATIVE DOUBTFUL POSITIVE

327 311 293 60% |0% 30%

A

MONTSERRAT

/ ////.

~

~

.

~

/

~

/

ST.MARY'S TOTALENROLLMENT TESTED COMPLETEDTEST NEGATIVE DOL~TFUL POSITIVE

240 190 160 "13% 16% 17%

I

]

TOTALENROLLMENT 464 TESTED 414 COMPLETEDTESTED 383 [ NEGATIVE 82% | DOUBTFUL 8% J POSITIVE 10% ,,, , .....,

PRIVATE CONVENT TOTALENROLLMENT 21 TESTED 2t COMPLETEDTEST 21 NEGATIVE 76% DOUBTFUL 10% POSITIVE 14%

FIo. z.--Montserrat, B.W.I.

TOTALENROLLMENT TESTED COMPLETEDTEST NEGATIVE DOUBTFUL POSITIVE

272 218 200 75% 17% 8%

TOTALENROLLMENT TESTED COMPLETEDTEST NEGATIVE DOUBTFUL POSITIVE

480 432 392 87% 9% 4%

KINSALE TOTALENROLLMENT TESTED COMPLETEDTEST NEGATIVE DOUBTFUL POSITIVE

238 213 207 61% 18% 21%

SEVENTH DAY TOTALENROLLMENT 76 TESTED ,68 COMPLETEDTEST 68 NEGATIVE 79% DOUBTFUL 17% POSITIVE 4%

I I I [ | | [

A T U B E R C U L I N SURVEY IN T H E ISLAND OF M O N T S E R R A T ,

BRITISH W E S T INDIES

I0I

Outside communications, as with all of the smaller West Indian islands, are poor. The only really regular means of transport was opened up recently by the Leeward Islands Air Transport, a subsidiary of British West Indian Airways. Heavy material such as the cotton has, of course, to be transported by sea. Owing therefore to the island's relative isolation there is but little travel between it and the other units of the West Indies. The chances of outside cases of tuberculosis bringing in active infection can consequently be regarded at the moment as negligible. The medical service, which consists of only three doctors for the whole island, is essentially the province of government, though the doctors are allowed outside practice. There is a seventy-bed hospital in Plymouth, and this provides excellent accommodation for about twelve cases of tuberculosis, but it is unfortunately poorly patronised by the existing cases. No X-ray facilities are available in the whole island, and as a result early diagnosis and follow-up are quite out of the question. The problem of tuberculous infection in this survey, therefore, had to be assessed entirely on the reactions to tuberculin of the individuals tested. In I95 7 there were five deaths from tuberculosis. Allowing for a population of I4,ooo, this gives a death rate of 35 per Ioo,ooo. In December 195 7 there were twenty-six known cases of tuberculosis-only one of whom was in hospital. A few of these are certainly arrested, but accurate information on the majority is completely lacking. During the two years i956-57 , 58 children under the age of i year died, 13 of these as a result of chest conditions (bronchitis or broncho-pneumonia). Whether any of these were really due to tubercle is not known, but at least 3 of them were contacts of diagnosed cases. In the survey the people of the island were extremely co-operative, and the amount of work done was limited only by the time available. A total of 2,924 individuals received a single Mantoux test using 5 tuberculin units of Purified Protein Derivative as the dose. O f this total, 192 individuals, or 6. 5 per cent., failed to return for reading of the reaction, leaving 93"5 per cent. of the original number examined as having completed the test. This is a gratifyingly high rate. The overall total was made up as follows: Adults (between I6 and 80 years) 333 Adults (schoolteachers only) .. 65 Children in eleven schools .. 2,42I Children (birth--i 5 years) not at school . . . . . . . . IO5 Total 2,924 O f the eleven schools examined, ten were elementary schools normally taking children between the ages of 5 and 15 and one was a small, private convent-school dealing with similar age groups. Unfortunately, the only secondary school was closed for the holidays and could not be investigated. This was the only school omitted in the Plymouth area. The group of adults, apart from the school teachers, was completely heterogeneous and comprised doctors, nurses, hospital patients and orderlies,

I02

CORY

prisoners, police, government servants, paupers and various adults who came for tests either to the health centre or to the schools. They came from virtually all districts of the island, and represented all the social levels in Montserrat. Tuberculin reactions have been graded as follows: Negative +

No trace of reaction M i n u t e n o d u l e a t site o f i n j e c t i o n , o f t e n u n d o u b t e d l y non-specific; under 5 ram. ( E d e m a o f 5-7 r a m . ( E d e m a b e t w e e n 8 a n d I5 m m . ( E d e m a b e t w e e n 15 a n d 20 r a m . G r e a t e r t h a n 3 p l u s or n e c r o t i c .

+ + + + + + + + + +

O n the tables these reactions have all been charted separately, but the group can be regarded as debatable, and m a n y authorities might consider such reactions as essentially negative when using them as a basis for BCG inoculation. Most reactions were read after 4 8 hours, though some were read at 7 2 hours. THE S U R V E Y AND FINDINGS O f the overall total of 2,924 individuals originally tested, 1,88o were completely negative, a further 3IO were questionable, while 542 were frankly positive to tuberculin; 192 failed to complete the test. O f the positive group, 84 individuals, or 11. 7 per cent. of that group, showed a very strong reaction. Deducting the 192 persons who failed to return for reading from the original number tested, a total of 2,732 completed the test. I n nearest percentages, therefore, of those completing the test the figures given above show the following: TABLE

I .--REACTIONSONALL INDIVIDUALS COMPLETING

THE TEST (Total 2732 )

Reaction Negative Doubtful Positive Total

Total number

Percentage

. . . . . . . . . . . .

1880 31 o 542

69 iI 20

. . . .

2732

ioo

It can be seen, therefore, that slightly under 70 per cent. of the population of the island have never had a primary infection with tubercle bacilli. I f the doubtfuls a r e included in this group, the figure rises to 8o per cent. Twenty per cent. are definitely infected, and at least one-tenth of these show severe reactions, suggesting that some of them are harbouring active or potentially active lesions. This point is important and should be borne in mind for future investigation, as it is highly possible that from these strong reactors may arise future infectious cases.

~"

A TUBERGULIN SURVEY IN THE ISLAND OF MONTSERRAT, BRITISH WEST INDIES

lO 3

A separate table has been prepared (Table II) to show the reactions encountered amongst the heterogeneous group of adults previously mentioned. It is a small group but is nevertheless fairly representative of the state of affairs generally obtaining in the island, as the persons in it came from widely separated areas, though admittedly most of them were from the capital city of Plymouth. TABLE I I . - - A D u L T S , BETWEEN I 6 AND 80 YEARS OF AOE ( T o t a l 333) (303 c o m p l e t e d t h e test)

Intensity of tuberculin reaction Age group

I

aVegative l

I6-24 25-34 35-44 45-54 55+

.... .... .... .... ....

29

Totals

....

%of 303 completing the test

+ 20

86

34

28

II

39

j

39

i

:I

IO0

I

6 4 0

5 6 3 5

68 65 43 57

19

I7

Io

333

6"3

5"7

23

4

i6

3

I

96

5 Ii

32

IT I7

49

l

Tota/s

returt

6

ic I4

I4

J

++++

I4

23

2 5 6 8

to

+++

+ .+

I3

24 7 7 19

Faile~

I OO

I2

6I

In Table II are also shown the percentages negative, doubtful and positive in the 303 adults who completed their tests. It will be seen that only 28 per cent. of all the adults were completely negative, I i per cent. were doubtful, and 6I per cent. were clearly positive. Table I I also shows that of the 303 adults completing their test, 36 (12 per cent.) gave a very strong reaction to 5 tuberculin units. The school teachers form a small but interesting group, comprising as they do practically all those teaching in the eleven schools examined (Table III). It will be seen that the negatives in this group form a higher percentage than in the general adult group. In addition we did not find a single strong reactor among the 64 teachers who completed the test. Finally, the children have now to be considered and compared with the findings in adult groups. Although the vast majority were reached by mass school testing, we were able to obtain some results on a group who were either too young to be at school, or who for some reason were away from school at the time when the test was done. In this group we tested lO5 children, varying from about months to 15 years of age. Table IV shows the results broken down by age groups. Twelve of these children failed to complete the test, leaving 93 for analysis. It will be seen that from 77 to 85 per cent. of the group were negative, while 15 per cent. were definitely positive. There were 3 children with strong reactions in this group, and one of them was less than 5 years old.

Io4

aORY TABLE III.--ScHOOL

TEACHERS

(Total 65)

Intensity of tuberculin reaction Reaction to 5 tuberculin units ..

Number

....

% of those completing the test

Negative

+

+

++

+++

31

6

17 [ IO

o

48"5

[ 9"5

++++ Necrotic

Total retlrn ~ _

65

42

58

TABLE IV.--CHILDREN NOT AT SCHOOL(IO5 tested; 93 completed test) Intensity of tuberadin reaction Age group Negative

#_

8 9

I

o-kk yr . . . . . I-l~{ yr . . . . . 2-5 yrs. . . . . 6-I2 yrs. . . . . I3-15 yrs . . . . .

38

Totals

72

....

% of those completing the test

I0

7

+ O O I 9

++

+++

O O O

4 7

77

4

++++ Necrotic

Failed to return

Totals

0

2

o

0

IO

I

2

I

0

0

8

42 16 27

2

I2

IO

lO5

I5

85

O n e v e r y striking feature presented itself here. Six children u n d e r the age o f 5 years lived in a yard, w h e r e we f o u n d t h e m b e i n g c a r e d for b y a " k n o w n " case o f tuberculosis w h o h a d refused to r e m a i n in hospital. All these six children were c o m p l e t e l y negative, a n d the " k n o w n " case herself showed a doubtful reaction. H e r s p u t u m h a d n e v e r b e e n p r o v e d to b e positive, a n d she h a d not b e e n X - r a y e d . I t seems likely t h a t she was not a case o f tuberculosis. R e f e r e n c e should n o w be m a d e to the largest a n d m o s t i m p o r t a n t g r o u p o f all, the children in the e l e m e n t a r y schools. Eleven o f these schools were visited, a n d tests were carried out on all the children f o u n d present. A total o f 2,42 I such children were tested, a n d T a b l e V shows the overall results. As the schools were too n u m e r o u s to be c o v e r e d in the t i m e available, a c h a r t of the island was p r e p a r e d (Fig. 2) a n d on it are p i n - p o i n t e d the k n o w n cases, as well as the locations o f the deaths occurring within the last two years, a n d certified as h a v i n g b e e n due to p u l m o n a r y tuberculosis. H a v i n g established f r o m this m a p t h a t two p a r t i c u l a r areas o f the island, P l y m o u t h in the south-west (seven schools tested) a n d St. J o h n s in the n o r t h (two schools tested), seemed to a c c o u n t for most o f the k n o w n cases a n d deaths,

A T U B E R C U L I N SURVEY IN T H E ISLAND OF MONTSERRAT~ BRITISH W E S T INDIES KNOWN TO CASES

o

TB OEATHS 1956/1957

•

SCHOOLS

*

IO5

ROADS MAJOR DISEASE AREAS

62°10'

JOHN J~

./~./~.CAVALLAHiLL

ST. PETERS TRONTSBAY

~,,,-

~'~AIR

STRIP

CENTREHILLS HARRIS

CORK HILL'

LONGGROOHO

• SOOER|EREtILL PLYMOUTH 6 SCHOOLS

KINSALE

.,~.... ",,~

G2°IO'

0 i

o

! I

i

Z ,I

i

3

SCALE Miles

i Kilometers

3 I

,

~

6

4 t

i

i

5 i

FIG. 2.--School Distribution and Results of Mantoux Test. an attempt was made to test all the schools in these two areas. A third small group of cases in the east, at Harris, led to the inclusion of two more schools in this area, bringing the total of schools examined to eleven. In the Plymouth area the secondary school, which had closed for the holidays, could not be tested. With this exception, all the schools in the suspicious areas were examined. Four other schools had to be omitted from the survey as there was not enough time to cover them. The areas in which they were situated, however, showed only one known case, and no known tuberculous deaths. The total enrolment of children in the eleven schools examined amounted

IO6

tORy TABLE V.--COMPREHEN$IVE TABLE OF ALL CHILDREN TI~STED IN ELEVEN Sc}{ooLs

(Total 242I )

Intensity of tuberculin reaction Age group

-~

+

++

+++

Negativexi

,

o

o

o

0- 4 yrs . . . . . 5-9 yrs . . . . . Io-x 4 yrs . . . . . 15-i9" ....

mo6 653

Io 9 I5°

64 I I64

14 / 2x

14 I8

3

8

~

Totals

i69i

%

2,

....

completing the test

74 86

[

++++

Necrotic

[

2

[ ~2

Ix

Failed to

Totals

relurn I

13

6i 78 9

x275 1088 45

'49

i

242I

I4

* No children older than 16 in these schools.

to 2,793 and of these 2,42 r were originally tested, I49 of whom failed to complete the test, leaving a total of 2,272 for final analysis or 94 per cent. of those tested. O f those whose tests were completed, 74 per cent. were negative, 12 per cent. were doubtful and 14 per cent. were definitely positive. There were 45 individuals in the whole group who reacted strongly, and 2I of these were under 9 years of age. As the total school enrolment throughout the whole island amounts to 3,432, this survey was able to complete the findings on 66 per cent. of all the school children in Montserrat, in spite of the fact that five schools containing 639 pupils had to be excluded. TABLE V I . - - A COMPARISON BETVv~EN URBAN AND RURAL SCHOOL CHILDREN WITH REGARD TO TItEIR REACTIONS (2,272 CHILDREN COMPLETING TEST). Urban, 6 schools; Rural, 5 schools

Tuberculin reaction Age group

Negative

Doubtful

Urba______~n[ Rura_____~l Urban Rural 0-4 yrs.* 5-9 yrs. Io-I 4 I5-,9t

.. .. .. ..

•.

87% xoo% 77% 187% 51% 74% / 7°%/44%

0% 8% ,6% '4% 0% '9% ,3%

,O#/o

Positive Urtan

R~ral .

o%L o%1 '3% I 5%1 33% } I2%1 3°%

37%

Totals on which percentages are based

~2 I2,4

,oio 36

* Figures in 0-4 and x5-I 9 age groups are too small for significant information. ~" No children older than I6 in these schools. Percentages are shown, and overall agegroup numbers. There was a fairly marked difference in the reactions shown by children in the urban schools (Plymouth) when compared with those in rural areas,

A TUBERCULIN

SURVEY

IN THE

ISLAND

OF

MONTSERRAT~

BRITISH

WEST

IO 7

INDIES

and Table V I has been prepared to bring out this point, which has been noted in similar surveys in other countries. I n the 5-9 and i o-14 age-groups, there is TABLE VII.--INDMDUAL SCHOOLSSHOWINGRESULTSIN URBAN AND RURAL UNITS (Percentages given are to nearest round number)

.Name of school

Covent, private .. Wesleyan ,, < Catholic Seventh Day Adventist St. Mary's .. Kinsale . . . . <

Cork Hill .. Cavalla Hill .. Bethel . . . . Harris .. .. St. J o h n ' s .. Totals Percentages

. . . .

Number tested and completed

Tuberculin reactions Negative

Doubtful

~.

%

,No.

%

76 63 60 79

2

IO

66

x6 9I 175 52

i8 31

i8o 2o7

I26

6x

12 xo 17 ~o 18

392 383

I56 14o 15o 34I 3x2

76 78 75 87 82

227~

t69x

21

I46 293

2o5 179 200

I00~/o

132

73

I7 37 32

16

15 34 34 32 263

74%

I'

II

8 17 9 8

-

Positive

NO.

%

87

I4 25 3o 4 17

44

2I

I7 24 16 I7 39

8

I4 8 io

--

i2%

i4%

N o t e t h e a p p r e c i a b l y l o w e r p o s i t i v e r a t e s i n t h e r u r a l schools.

a significantly higher proportion of positive reactors in urban schools than is to be found in their rural counterparts. T h e i5-i 9 group, however, shows a reversal of this finding due to the fact that in one school (St. Johns) there were 4 positive reactors out of the 5 pupils in the school in this age-group. This particular school serves a part of the northern area where it was noted that 4 cases of tuberculosis had occurred. Table V I I shows the names of the individual schools, the numbers completing tests in each, and the results, school by school. It also differentiates between the u r b an and the rural schools. From this table it can be seen that three schools in the urban area show more than 20 per cent. of their pupils with a positive reaction. T h e Catholic school rises as high as 3 ° per cent. This is believed to be the result of contact, in the school, with a girl who was found to be an active case with a positive sputum. No rural school runs as high as a 15 per cent. positive rate, though Cavalla Hill and St. J o h n s - - b o t h in the suspicious area in the n o r t h - - h a v e rates o f io per cent. or somewhat over. Harris, Bethel and Cork Hill in country areas where there have been few known cases, r un infection rates of 8 per cent. or less. O n M a p 2 have been charted all the salient features of the survey, and reference to it will give the results found in all the areas tested.

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CORY

Summary The survey appears to have established the following facts: Tuberculous infection in adults in Montserrat is fairly widespread (6I per cent.). In children it is low, rising from 4 per cent. in some rural schools to as much as 25 to 30 per cent. in the urban schools. Rural schools in areas where known cases have occurred show a higher infection rate than those in " c l e a n " areas. About one-tenth of the positive reactors in the schools show strong reactions, suggesting that at least some of them have active or potentially active diseases. There are no facilities for X-ray work, and laboratory facilities exist only for sputum examination by smear. As a result of this, an adequate case finding programme is quite impossible at present. There is a very satisfactory ward for isolation of tuberculous cases, b u t the people refuse to remain in hospital after a month or two on drugs, as a result of their having begun to feel better.