Pergamon

Sot. Sci. Med. Vol. 38, No. 4, 623-629, 1994 PP. Copyright 0 1994 Elsevicr Science Ltd

Printed in Great Britain. All rights reserved 0277-9536194 86.00 + 0.00

RESULTS FROM A COMMUNITY INTERVENTION PROJECT IN THE NICARAGUAN MINING COMMUNITY

EL LIMON. AN OVERVIEW

RODOLFO F’E~~A,‘,* ,~KE THORN** and AURORA ARA&N’

’ Department of Preventive Medicine and public Health, UNAN, Leon. Nicaragua and *Department of Social Medicine, Karolinska Institute, Stockholm, Sweden

Abstract-The first steps of a community involvement health project using the principles of community diagnosis and popular participation were carried out in a small Nicaraguan mining village during the second half of the 1980s. Using existing archives and obtaining new information aided by local organizations, priorities could be established for health and safety surveillance within the mining company, as well as for further investigations concerning what seemed to be dominant health problems in the community: serious accidents among the economically active population and diarrhoea and respiratory tract infections among children, as well as infections, and other health indicators of malnutrition. Workers also presented chronic simple bronchitis, ventilatory obstructive disturbance and hearing loss that were strongly associated with working conditions. These results helped to direct health priorities and educational activities at the local level with both the general and working population. The wide experience gained from this study has encouraged us to strengthen the link between research and action and in performing studies in close cooperation with local organizations.

Key words-ommunity diagnosis, popular participation, mining industry, developing countries, transmittable diseases, occupational diseases

lNTRODUCTlON

In 1979, a new government succeeded the Somoza family’s more than 40-year-long dictatorship in Nicaragua. It faced a poor public health situation even by Latin American standards, which is well illustrated by the following data [l-6]:

50% of the population shared 16% of the national income; 41% of the population lacked sufficient income to satisfy their basic nutritional needs; 94% of the rural population did not have access to good quality drinking water; 47% of the households lacked sanitary installa- tions such as latrines and organized waste dis- posal; 68% of the children under 5 were mal- or under- nourished; Life expectancy was 52 years; Diarrhoeal diseases were the primary cause of death, followed by other infectious diseases like pneumonia, influenza, measles, tetanus and malaria.

A health policy programme designed to alleviate these problems was introduced in August 1979. One of its aims was to modernize and increase access to the existing rudimentary curative health system. First priority was, however, given to the creation of a preventive health infrastructure, a

*To whom correspondence should be addressed.

public health system [7]. Geographically dispersed health centres were successively built as the very basis of the system. Curative medicine was delivered at these centres, and based on them a number of preventive health programmes such as vaccination campaigns, draining of stagnant water, rational waste handling, health education etc. were carried out with remarkably good results [7-111 during the first 5 years. Such preventive programmes were delivered in a system of community involvement- popular participation-according to one of the six defined principles of the national health policy [7].

The concept of popular participation is generally viewed as a means of improving the efficiency of the official policy and as a goal as such, where the involvement is part of a generalized, long-term process of raised consciousness [12]. In Nicaragua rational planning also necessitated utilization of the communities’ knowledge of their specific health problems and local infrastructures as well as the inhabitants as a resource to carry out community- based health programmes in an efficient manner [lo, 13, 141.

BACKGROUND AND AIM OF THE STUDY

Following the adoption of the new health policy in Nicaragua, a long-term research project was initiated in the mining community ‘Mina El Limon’. The project was financed by SAREC (Swedish Agency for Research Cooperation with Developing Countries)

623

624 ROWLFO PERA et al.

with the purpose of training Nicaraguan junior re- searchers in public health sciences up to masters and doctors degrees. The research design and execution was guided by the scientific philosophy of the in- volved Nicaraguan participants: that research in their poor and disease-ridden country should be directly linked and integrated with, or even be, development actions [ 151.

With the new health policy followed a need to become more informed on existing health problems, that is, a need to establish an appropriate health information system (HIS). The above-mentioned re- search project included a study with two basic aims:

(1)

(2)

To increase the knowledge base about living conditions, the working environment and the health of the population in a Nicaraguan mining community by using a community diagnosis approach. To establish an infrastructure (HIS) facilitating public health planning and activities resulting in the creation of programmes relevant to both the working conditions and major community health problems.

The study was designed in collaboration with the popular organizations in the village, and carried out with their very active support and participation. Community involvement was considered an import- ant part of the link between research and develop- ment action, and it was therefore an aim as such. Other important long-term aims were to formulate rational health and environmental programmes for the miners representing the economic core of the population as well as for their families. These pro- grammes were based on more detailed analyses of different parts of the study that are presented in separate articles [16]. The present article is an overview of the study concentrating on the following issues:

The relevance of findings among the general popu- lation and workers. The health information system: suggestions for health priorities. The efficiency of the methodology including cost- effectiveness.

MATERIALS AND METHODS

Study area

The study was carried out in an isolated gold-min- ing community, Mina el Limon, situated in a hilly, dry, volcanic area. Gold ores have been exploited there on an industrial scale since 1941 by the Cana- dian company NORANDA (171. Mina el Limon was nationalized in the autumn of 1979. The industry has given rise to population settlements (basically miners and their families) in three larger villages, Mina El Limon, Santa Pancha and Gahlao, and in single or small groups of households spread over an area of

approx. 170 km*. The dominant economic activity was the mining industry. Systematic information on demographic characteristics or living conditions in the community was not available at the outset of this study.

The mine consists of a central area with workshops and a processing plant that is fed by crude gold ore extracted from a nearby open pit and from some more peripherally situated underground mines. Working conditions are poor owing to difficult geological conditions, old, worn-out equipment inherited from NORANDA and the community’s lack of knowledge and awareness of occupational and environmental health problems.

Study population

The study population was defined as all inhabitants of the above-mentioned mining villages. Owing to deficient registers, the number, age and sex compo- sition of the total population was unknown at the outset of the study. The population of workers employed by the mining company was, on the other hand, fairly easily accessible through good company registers. The study was divided into two parts:

(1) Health and living conditions for the commu- nity’s population in general. Study popu- lation = all community inhabitants.

(2) Health and the working environment for the employees of the mine. Study population = all 824 male persons between 20 and 60 years of age on the company’s payroll in April 1985.

For both parts of the study the cross-sectional survey was chosen as the principal method.

Performing the studies

Study of the general population. The primary aim was to obtain a basic descriptive community diagno- sis covering different facets pertinent to health. The collection of data for this was done in the autumn of 1986 after thorough information on the purposes at a number of meetings with the popular organizations. Information on population size and composition, occupation, literacy and household conditions was collected by representatives of the community’s 6 existing popular organizations and by 30 locally recruited ‘brigadistas’ who were trained for this pur- pose. They visited all households, registering obser- vations and interview results on a simple form. Information on morbidity and mortality was col- lected by reviewing the health centre’s records. Infor- mation on nutritional status was obtained by measuring the height of all 6-year-old children and comparing it with national standards. The quality of the drinking water was assessed by taking bacterio- logical samples from the drinking water sources. Other information such as on cultural activities, recreational facilities, access to and distribution of food, communication networks, historical back- ground, the local health system etc. was gathered

A community intervention project in Nicaragua 625

through interviews with the popular organizations’ representatives and with older citizens as well as from archives.

Study of miners and their working environment. This part of the study was planned in 1984. As part of the planning, interviews were conducted with two entire work-shifts of underground workers and the only work-shift from the workshops. The underground workers reported the following as their major health concerns: aching joints and muscles, hearing prob- lems, respiratory problems, cough, dermatological problems. The workshops workers reported the fol- lowing as their major health problems: stomach pain, headache, fatigue.

The information led to the hypothesis that the miners’ health problems were dominated by occu- pational diseases in a stricter sense, while the rest (mechanics, maintenance, service workers) suffered relatively more from diseases generally prevalent in the community.

The study itself was carried out between April 1985 and July 1987 as a cross-sectional study. The subjects were interviewed and examined by a doctor aided by a nurse recruited from the community’s health centre. Spirometry, audiometry and chest X-ray were per- formed, haematocrit measured and stool specimens examined for parasites. A hygienic survey of different work areas concerning noise, dust and climatological factors was carried out in 1986 and 1987 by a locally recruited and trained team consisting of union repre- sentatives and company and health centre technicians trained and led by an industrial hygienist. All equip- ment for medical and hygienic measurements, such as a spirometer, an audiometer, an X-ray machine, a soundmeter and dustmeters, was donated by the project to the health centre and the company’s Health and Safety Unit.

Union representatives participated very actively throughout the project period. They had a key role in spreading information on the project and its objec- tives and procedures to the workers. The union also organized its members in their leisure time to build a house in the health centre’s grounds which was used as the physical base of the project. A long-term study circle for workers concerning the working environ- ment was started during the course of the project. The popular participation, and also the coordination of activities and different organizations and agencies, was formally organized as shown in Fig. 1. The project acts as the agent bringing and integrating training, equipment and responsibilities regarding occupational and environmental health issues to the health centre and the mining company under the guidance of a governing committee with popular representation.

Occupational exposure

As a very high proportion of the dust samples from the underground work-sites were destroyed by the high humidity there and by oil and sand

contamination, classification of the employees according to exposure to dust and other probable noxious air contaminants was based on information from the labour union, the company management and the Health and Safety Unit. Classification ac- cording to exposure to noise was based on noise measurements.

The classification resulted in the following categories: Work Category I (Cat I): less exposed to noxious air contaminants and to noise up to 90 dB(A), basically workers from maintenance and service sections. Work Category II (Cat II): more exposed to noxious air contaminants and to noise levels ranging from 91 to 119 dB(A), that is the workers engaged in ore extraction or ore process- ing.

Outcome measures

Chronic simple bronchitis was defined as productive cough for 3 consecutive months for more than 2 consecutive years [18]. Obstructive lung disorder was defined as present when the registered FEV, was ~80% of the expected according to preliminary normal spirometric values from Nicaragua. [I91 Noise-induced hearing damage was defined as present when there was a mean hearing threshold of > 35 dB over the frequencies 500,lOOO and 2000 Hz and at the same time a mean hearing threshold of 2 50 dB over the frequencies 3000,400O and 6000 Hz in at least one of the ears. Anaemia was defined as haematocrit ~40%. Smoker was defined as current cigarette smoker. Illiteracy was defined as inability to read or write. Big family {support-load) was defined as 5 or more children to maintain.

Statistical analysis

The outcome measures have been calculated as prevalences. Prevalence rate ratios have been used as a measure of the association between the different parameters and the two work categories. Stratifica- tion by age has been done with the Mantel-Haenszel method and Miettinen’s test-based confidence inter- vals have been calculated.

Govemlng Committee

Fig. I. Organizational form attempting to secure and integrate work of different local operative units including

popular organizations.

626 ROWLFO PEX?A~~ al.

RESULTS

General population

The community’s population totalled 7948 per- sons, with a very young age profile, 9 1% of the males being younger than 50 years and almost 53% younger than 15. The corresponding figures for females were 92 and 50%, respectively. Sixty-seven percent of the population lived in the three main villages, Mina et Limon, Santa Pancha and Galilao, the rest in single or small groups of households spread over an area of approx. 170 km*.

The dominant economic activity was mining. A total of 1879 persons in the community were econ- omically active and 49% of these were employed by the mine, 33% in services such as the health and school systems or working as craftsmen or in com- merce, and the final 18% were working in agricultural cooperatives or as independent peasants.

Houses were very small, 66% of the households having only one room at their disposal, which meant on average more than 4 persons per room. Wall constructions were as a rule of wood, roofs of zinc and floors of unpolished cement or earth. Ninety-two percent of the houses in the three main villages had electricity but only 2% in the rural areas. Only 64% of the households had latrines. Waste water was disposed of in gardens or even in the streets, as were all kinds of solid waste products.

There were two main sources of drinking water supplying 90% of the population living in the three main villages. One of these, Cebadilla, supplies the villages of Mina el Limon and Santa Pancha. This is a subsoil water source from which water is pumped and stored in a nearby tank and then distributed in pipes to the Mina el Limon households. From this source, water is also transported in pipes to Santa Pancha, 7 km to the east, where it is also stored in a tank before use. The second main source, Galilao, is a deep underground well that through pipes supplies the village Galilao. The mean content (10 samples) of total coliform bacteria in the Cebadilla water was 1400/100 ml while the water of Galilao contained no bacteria.

Seven primary schools exist. Almost all children in the ages 612 years attend these schools. There is also an incomplete secondary school and a centre for adult education in the village Mina el Limon.

The present health system consists of a health center in Mina el Limon and three health stations, two of which are located in Santa Pancha and Gahlao, respectively and the third in a rural district. The health centre is staffed by two doctors, two nurses, a number of auxiliary nurses, one dentist, one pharmacist, one sanitary inspector and a number of assistants. The health stations are staffed by auxiliary nurses. Health activities are carried out according to the national health policy guidelines, locally adapted with the assistance of a Community Health Council

Table 1. Number of visits to the Mina el Limbo health centre January-September 1986

Main diagnostic category No. %

Acute respiratory disease 3396 14.6 Other respiratory disease 813 3.5 Acute diarrhoea 1233 5.1 Other intestinal disease 2846 12.3 Genito-urinary disorders 1649 7.1 Skin disease 1695 7.3 Nervous disorders I570 6.8 Musculoskeletal disorders 1233 5.3 Diseases of pregnancy 476 2.0 Circulatorv disorders 475 2.0 Miscellaneous 7875 34.0 Total 23220 100.0

Grouped according to main diagnostic category.

consisting of representatives from all popular organizations.

The morbidity of the community as registered by the health centre during the first three quarters of 1986 is shown in Table 1. The mortality in the age interval 1 month to 14 years from April to September 1986 was 6 cases; 5 of these were due to diarrhoea, pneumonia and meningitis. In the economically active ages 15 to 64 years, 7 deaths were registered during the same period. Five of these were due to accidents and the remaining 2 to pulmonary tuberculosis.

Retarded growth was found in 25% of the 493 measured first grade children, severely retarded in 3.7%.

Miners and the working environment

Of the entire male population of 824 employees in the age interval 20-50 years on the company’s payroll in April 1985, 675 (82%) could be interviewed and examined up to July 1987. Six of these were excluded from the analysis because of incomplete information. Of the remaining 669 workers, 49% belonged to Work Category I. Means for height, weight, age and duration of employment by the company did not differ much between the two exposure groups. Substantial differences were found concerning all outcome measures, associated as they were with Work Category II, that is the workers engaged in direct ore-handling (Table 2).

costs

The direct costs for the project are shown in Table 3. They have been calculated for the period 1984 through 1987. During this time, the investi- gation was planned, investment in equipment made and all fieldwork carried out. A lot of voluntary work, like the construction of a house as a physical base for the project and for future preventive health activities in the health centre’s grounds, and the collection of the data by 30 volunteer field workers, ‘brigadistas’, has not been possible to evaluate econ- omically.

A community intervention project in Nicaragua

Table 2. The relationshiu between outcome uarameters and workina conditions in Mina el Lim6n

621

Cat I’ cat II’ RRb 95% 95% Outcome crude confidence RR< ad confidence Parameters No. % No. % Cat II vs Cat I interval Cat II vs Cat I interval

Chronic simple bronchitis l/319 2.2 241318 7.5 3.44 I .5&7.87 2.81 I .23-6.44 Ventilatory obstructive disturbance 5/305 1.6 201322 6.2 3.19 I .4&9.91 3.62 1.35-9.71 Noise-induced hearing damage II/324 3.4 39/338 11.5 3.40 I .11-6.52 2.99 1.565.75 Anaemia 41/280 14.6 851218 38.9 2.66 I .92-3.70 2.54 1.81-3.55 Big support-load 841324 25.9 1431339 42.2 I .63 I .3&2.03 I.41 1.15-1.71 Smoking 157/326 48.2 2031343 59.2 I .23 I .07-l .42 I .22 l.O&l.41 Illiteracy 39/326 12.0 151/343 44.0 3.70 2.68-5.06 3.38 2.4G4.61

‘Cat I and II = work categories according to definition in the text b RR = rate ratio based on prevalence. ‘Rate ratios adjusted for age by method of Mantel-Haenszel.

DISCUSSION

Health work based on community diagnosis was introduced in the 1950s [20] and first used in practice in health planning in developing countries towards the end of the 1960s [21]. This type of collective diagnostic process generally has three steps: (1) community diagnosis in a descriptive sense, (2) community analysis and (3) community intervention programmes. In Mina el Limon, the first two steps of this concept were used to get an increased knowledge base on health and factors relevant to health and health planning. A rather detailed description of the community from a wide variety of perspectives was made possible by the intensive work of local popular organizations, and by reviewing existing archives.

Only that part of the collected information which is directly relevant to health has been presented here. It gives the picture of a community with a young population, even for Nicaraguan conditions, living in over-crowded houses of low standard. Household facilities for adequate disposal of liquid as well as solid waste products were nonexistent and those for the disposal of excrement were unsatis- factory. The 50% of the community’s total popu- lation that lived in two of the three main villages got their drinking water from a source shown to have a bacteria content exceeding the Swedish per-

Table 3. Estimation of oroiect cost 198487

costs U.S. s Investments

X-ray machine Audiometer Soundmeter Vitalograph Dustmeter Miscellaneous Subtotal

Material For construction of office at health centre

Salaries Nurse, full time Doctor, half time Subtotal

Foreign advisers Total cost

49.000-

2.000-

25.000:- l3.OOQ- 89.000:-

missible limit for bacterial contamination of drinking water by more than 140 times [22]. A public school system with good geographical accessibility and coverage and an excellent attendance had been constructed during the first half of the 1980s. Sources of information on health were the records of the health centre. These were of poor quality. Consul- tations with doctors were registered under main headings and in such a way that new cases could not easily be separated from repeat consultations. For this reason, and also for a number of others, the frequencies of diagnostic categories given in Table 1 only give an indication of the magnitude of what is probably the dominant health problem in the community: infectious diseases of the respi- ratory and gastrointestinal systems. This is in agree- ment with the findings of poor hygienic living conditions and poor drinking water, as well as with the finding of a rather high prevalence of malnu- trition among the 6-year-old children. The regis- tration of deaths was also poor and the figures presented are probably underestimes. However, the mortality pattern, with 5 out of the 6 deaths during the 6-month period among children up to 15 due to infections, is in agreement with the indications given in Table 1 and with the living conditions. The mor- tality pattern among the economically active popu- lation was quite different, with 5 deaths of the 7 registered due to accidents and the remaining two due to pulmonary tuberculosis. The fact that more than 90% of the registered deaths were due to accidents or infections, which in principle are preventable, has immediate implications concerning what actions could be taken.

The inhabitants employed by the mining company were as a group well defined and could therefore be studied more deeply. The results from this part of the study show that such disease states as chronic simple bronchitis, ventilatory obstructive disturbance and hearing loss were strongly associated (Table 2) with the working conditions classified as Cat II, that is work with direct ore handling. A number of other studies from, for instance, Swedish iron ore mines [23], South African gold mines [2426] and Australian coal and gold mines [27,28] show similar results

628 RODOLFO PERA et d

concerning respiratory disease, and the damaging effects of high noise levels are well known [29].

Both sets of main results presented here (infections and malnutrition as apparently dominating health problems among the general population and respirat- ory and hearing problems among the Cat II workers) are in accordance with those of many other studies of miners and Third World populations [24-29, 30-321. The findings are therefore reasonable and may be considered relevant.

What is important, however, is not primarily these health findings but the process that produced them: two cross-sectional studies, a very simple one for the initially demographically unknown general popu- lation, and a somewhat more sophisticated one for the better defined mine industry population. These two surveys were developed, designed and carried out in close cooperation and integration with the local popular organizations, health volunteers, health centre and mining company. The performance of the studies resulted in a number of educational activities, the revision and improvement of health centre records and the creation of a population register for the workers. In other words, gradually during the course of the surveys and as a product of them, the material basis of a health information system (HIS) was developed.

Table 2 illustrates how health information can suggest the direction of health priorities at the local level. The table shows that illiteracy and anaemia, and also smoking and a big family (support-load), show a strong to moderate association with Cat II. As there are no reasons to suspect exposures in the working environment as causes of anaemia, this and other parameters mentioned are considered to be indicators of unfavourable socio-economic con- ditions. Thus, Table 2 suggests an unfavourable situation for approximately half of the company’s employees directly engaged in ore-handling. Not only does this group show an increased rate of respiratory disease and hearing problems but also of anaemia, a big support-load, illiteracy and unhealthy habits like smoking. Since CAT II workers (the ore handlers) are paid more it was thought that their higher income would translate into better living conditions and so better health. However, higher wages do not remove the occupational and environmental health hazards that account for the higher morbidity. This con- clusion has led to the creation of a health centre- based surveillance programme based on existing resources and giving priority to this unfavoured half of the workers, to their families and to their working environment.

The long-term efficiency of the HIS cannot yet be evaluated, and therefore neither can its cost-benefit ratio. Its long-term benefit will, however, depend on to what extent it can retain the active aid and support of local citizens and bodies. It will also depend on to what extent it can help focus on health problems for which potential remedies can be implemented, evalu-

ated and the results fed back to influence and further develop and improve the HIS. The system has already been used in a recently terminated incidence study of respiratory and diarrhoeal infections among children in a limited sector of the community, and in the near future it will be used for an epidemiological study of accidents in the community.

The direct costs (Table 3) of the project were high. However, 55% of the costs concerned investments in the health centre in the form of equipment with daily use in curative and preventive medicine, as well as in environmental surveillance far beyond the project’s aims and period. The experience of cross-sectional surveys as the basic tools with which to develop local health and environmental knowledge as well as for the development of a first HIS was positive. Preliminary results from the surveys during the course of the investigation stimulated the local participants and helped to focus interest and activities on local health problems and sanitary conditions. The general conclusion of the study is that the cross-sectional design, planned and carried out in close cooperation with local popular organizations, facilitates establishment of a strong link between research and action. as well as permitting the development of this type of community diagnosis, and can therefore be recommended for testing in other poor, Third World rural villages.

Acknowledgements~The study was supported by Sarec (Swedish Agency for Research Cooperation with Develop- ing Countries). We also thank the popular organizations at the Mina el Limbn. Special thanks to the Brigadistas. without whom this study would not have been done.

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