THE VULNERABILITY OF NURSING WORKERS TO TUBERCULOSIS IN A TEACHING HOSPITAL 1

This study aimed to identify aspects that potentially increase the vulnerability of nursing workers to tuberculosis, through the verification of personal life, work and disease knowledge indexes. The sample is composed of 81 nursing workers involved with assistance in the night and day shifts at USP Teaching Hospital, who answered a questionnaire about life and work habits. The sample aggregated the indexes that increase vulnerability to tuberculosis: long professional experience in hospitals and work load longer than 12 hours. Data show that nursing auxiliaries and workers from the night shift in general have a higher number of vulnerability indexes.


LA VULNERABILIDAD A LA TUBERCULOSIS EN TRABAJADORES DE ENFERMERÍA DENTRO DE UN HOSPITAL UNIVERSITARIO
En este estudio se buscó identificar aspectos que pueden potenciar la vulnerabilidad de los trabajadores de enfermería frente a la tuberculosis, utilizando la verificación de indicadores de vida personal, trabajo y los relacionados al conocimiento de la enfermedad.La muestra estuvo conformada por 81 trabajadores de enfermería involucrados con la asistencia en los turnos diurno y nocturno del Hospital Universitario de la USP, los cuales respondieron a un cuestionario sobre los hábitos de vida y de trabajo.A través de la muestra fue posible mostrar indicadores sobre la vulnerabilidad a la tuberculosis: una larga experiencia profesional en hospital y jornada con más de 12 horas diarias.Los datos mostraron que, auxiliares de enfermería y trabajadores del turno nocturno presentan mayor número de indicadores de vulnerabilidad.Gran parte de los trabajadores mostraron conocimiento equivocado sobre la enfermedad, a pesar de brindar atención a pacientes con tuberculosis..In Brazil, it is estimated that between 35 and 45 million of the total population are infected by M. tuberculosis, with about 100 thousand new cases and between 4 and 5 thousand deaths every year (1) .Almost one fifth of the cases occur in São Paulo State, where 18,975 cases were notified in 1998 (1) .to the need to survive (2) .

A VULNERABILIDADE À TUBERCULOSE EM TRABALHADORES DE ENFERMAGEM EM UM HOSPITAL UNIVERSITÁRIO
In view of the disease's eminently social nature, initiatives to control it need to focus on specific actions, but also incorporate the change in populations' living conditions.Hence, it is important to understand the disease as a process developed in individuals who are part of a certain form of social organization and, as such, are subject to distinct risks and potentialities, depending on the specific groups they belong to.That is, in the end, the disease is due to different socioeconomic groups' peculiar production and social reproduction conditions.This leads to the production of distinct potentialities to strengthen or exhaust the human body.This relation between beneficial and destructive forces is expressed in distinct healthdisease manifestations (3) .
Thus, daily work and knowledge can be fundamental in terms of people's vulnerability.The term vulnerability (4)  In view of this vulnerability model (4) , this study aimed to identify potential vulnerability indicators of tuberculosis in nursing workers, which can contribute to its prevention and control.The study is based on the observation that health workers in hospitals present a specific risk of getting tuberculosis, mainly the multiresistant forms, which has been widely documented in literature (5) .

OBJECTIVES
To characterize the general living and work conditions of nursing professionals who work day and night shifts and to identify variables that can evidence potential vulnerability to tuberculosis.

DESIGN AND METHOD
The We carried out a descriptive study.The collected data were systemized in EpiInfo 6.04 software, to extract absolute and relative frequencies.

Personal characteristics of the nursing workers
The study sample mainly consisted of female workers between 31 and 42 years old (42%, n: 34).
In terms of education, 27.2% had only finished basic and 34.6% secondary education.
According to the staff list at the hospital's Nursing Department, at the time of data collection, nursing aids corresponded to 50.5% of the Department's total staff, against 17.3% technicians and 24% nurses.
Hence, the study sample corresponded to the structure of the nursing workforce in Brazil.
With respect to the shift distribution of the professionals who answered the questionnaire, 53.1% (43) worked during the day and the remainder at night.The day shift is subdivided in two six-hour periods (morning and afternoon).The night shift, on the other hand, covers 12 consecutive work hours, followed by 36 hours of rest.It should be reminded that night work can be considered a factor of destruction, of vulnerability, to the extent that it demands greater mental effort to maintain the same performance level as in activities performed during other shifts (6) .
Another important piece of information is that most workers belonged to small families of up to 4 people (72.9%When asked about drugs use, 34.6% (28) indicated they had never used any kind of drugs (alcohol, tobacco, marihuana, crack, cocaine, injectable drugs, glue, tranquilizers and stimulants).
Nevertheless, alcohol and tobacco were the most used drugs, with the latter occupying the first place.

Their work conditions
Most participants (91.4%) in both shifts mentioned they chose their work hours and considered themselves satisfied.About 69.1% (56) indicated they worked a fixed shift and did not need to change their work hours.This would represent a harmful and exhausting factor with respect to the health-disease process, as inconstant work practices jeopardize the maintenance of the homeostatic balance established by the sleep-wake cycle (8) .Only 17.3% (14) informed that they also worked at another hospital, which evidences the possibility of greater exposure to biological and mental exhaustion in comparison with people who have one job only.From the total group, 34.6% (28) worked more than 12 hours per day.

Aspects that can influence vulnerability to tuberculosis
With respect to vulnerability to tuberculosis, this included aspects related to the professionals' knowledge about the disease, as well as their knowledge access and frequency of care delivery to tuberculosis carriers, broadening the individual vulnerability concept (4) .
As to transmission form, 58% (47) considered that the probability of catching the tuberculosis bacillus simply by talking was low.In fact, besides inhalation of the bacillus, the disease needs an impaired immunological system to develop.About 5% of infected persons can get ill, although the reasons for this have not been fully clarified (9) .However, some .
It should be emphasized that a majority of these conditions results from certain living conditions.
Moreover, the bacillus load, its virulence and the organism's hypersensitivity state also interfere in the development of the disease (9) .
Although patient can still eliminate bacilli (9) .It should be highlighted that 13.6% (11) mentioned contamination was impossible, while 3.7% ( 3) could not answer the question.This again evidences the need to offer information to this group of workers, as disease control also depends on them.Moreover, 14.8% (12)   indicated that contamination was very probable.It should be emphasized that there is no risk for contacts when the index case starts to use chemotherapy adequately for at least two weeks (9) .The probability of catching a tuberculosis infection is related to the density of organisms in the environment at a given time, which may be related to the patient, to drugs use and to the nature itself of the environment.A series of factors are related to the person, such as the nature of the expulsive effort when coughing, the bacteriological state of the bronchial secretion, the extent of the disease and the presence of cavity (9) .It is surprising that most of the above mentioned workers were nurses (45.5% = 5).Another noteworthy aspect is the fact that about 23.2% of day and 34.2% of night works answered this question wrongly.
On the other hand, about 87.7% of the interviewees considered that the transmission of the bacillus through carriers who were not receiving treatment was highly probable.Again, it is remarkable that 11.1% (9) mentioned low probability, 55.6% (5)   of whom were nurses, while 1.2% (1) manifested this was impossible.This once again exposes the lack of knowledge about this issue.Of all nurses, 20.8% (5)   believed the probability of transmission was low, while about 13.9% and 10.5% of day and night shift workers, respectively, gave a wrong answer to this question, in line with our findings for the previous question.
As to the possibility of contamination through the use of personal objects (cups, plates, cutlery etc.) which can contain the bacillus.However, only bacilli suspended in the air reach the alveoli and start the primary lesion (9) , while the largest particles tend to be deposited on the floor and mixed with dust, while the smallest float in the air (9) .The atomization of secretions to constitute contaminating particles is related with the sputum's physical-chemical characteristics and the vigor of the cough.Thus, thick and adherent sputum produces a lesser quantity of infecting particles, as opposed to more liquid types.
Only 1% of the bacilli in suspended droplets survive for a couple of hours, provided that they are in unventilated locations that are not exposed to sunlight, which is fatal for the bacillus.Hence, the main entry door is through the pulmonary alveolus.
Moreover, with respect to transmission, we found that the nursing workers considered contamination was probable when sleeping in the same room (95.1%) and living in the same house (88.9%) as the patients.It is a fact that the probability of infection is higher among contacts inside than outside the home.There exists a direct and statistically significant relation between proximity (same bed, same room, same house) and relationship (mother, father, siblings and other relatives) on the one hand and infection and the disease among communicants on the other (9) .Other important factors are the ventilation conditions in the environment the transmission is established in.Ventilated environments in which air is constantly replaced provide more safety in contamination prevention (9) .
Almost professionals who are directly involved in care (10) , which is why this can constitute a tuberculosis vulnerability indicator in the study sample.In terms of professional category, nurses revealed to be more frequently involved in care for tuberculosis patients.
The largest number of workers with previous tuberculosis care delivery experience was found at the ICU and Medical Clinic. In

DISCUSSION
The sample includes some indicators of potential vulnerability to tuberculosis, such as long professional experience at a hospital unit and working more than 12 hours per day (including another job).
The length of the work period in the health area is important, as it evidences the time of exposure to disease-causing agents, including the one that causes tuberculosis.In a study of professionals who worked in this area, it was observed that 40% of tuberculosis cases occurred in the first 2 years after admission (11) .
Another research, at a reference outpatient clinic for pulmonary diseases and tuberculosis of the São Paulo State Health Secretary, demonstrated that professionals who had worked longer at the institution were all reactive to the tuberculin test five years (9) after their admission.
Data evidenced that the nursing aids present should assume particular responsibility should be assumed to implement control measures (13)(14) .The fact .
Although we found no important difference between the day and night shifts, we suggest further research, using statistically appropriate measures, as this is a powerful vulnerability variable, as this factor does not only change the biological system, but also impairs the individual's social dynamics, as night shift workers are obliged to use what should be their rest hours to respond to daily events: society and the family still functions at a traditional daytime activity rhythm (8) .
The night shift limits or makes the worker's participation in associations, organizations, parties and unions etc. impossible.Moreover, the rest periods made obligatory by the shift system generally do not occur at weekends, which substantially changes the utility of this free time.This creates feelings of disadvantage and even social isolation in most workers (6) .
Although some professionals work night shifts because they choose to and adapt easily, in view of the above, all earlier described transformations can be considered as destructive factors (counter-values) in the health-disease process since this shift, in general, is imposed and accepted, given existing difficulties in the job market.
We also suggest a research with a larger population sample, besides the application of a tuberculin test to detect clusters of professionals who, after a period of time, can present PPD conversion, with a view to the implementation of disease control, protection and prevention standards for workers at this institution.
There is a need for increased awareness about the fact that tuberculosis can be properly cured and that health workers can also be susceptible.They should be stimulated to seek emergency care in case of compatible symptoms, without fear of any kind of censorship, considering the need for an active search of cases, including in the intra-hospital environment.
that the disease mainly affects people in the economically productive age, besides causing the unavoidable suffering of the disease itself, reduces productivity and can entail the need to temporary replace the work force, besides the need to train new workers, which means an important indirect cost.In this respect, the WHO indicates that, at global level, tuberculosis decreases productivity by about 12 billion dollars every year and also results in a potential family income reduction by about 20 to 30% ).
majority (87.7%, n: 71) indicated that they watched television, and a majority preferred watching the news (45.7%).No expressive difference was observed in terms of work shift, as both day (48.6%,n: 18) and night shift workers (51.3%, n: 19) used television to watch the news.The vulnerability of nursing workers... Souza JN, Bertolozzi MR.