ADHESION TO TUBERCULOSIS PREVENTIVE MEASURES BY HEALTH WORKERS IN DIAGNOSTIC AND TREATMENT CENTERS IN DOUALA-CAMEROON

Background: Tuberculosis (TB) remains a major health problem in Africa and more particularly in sub-Saharan countries such as Cameroon due to its impact on mortality, morbidity and socio-economic repercussions on the population in general, in this case in big cities like Douala. In 2018, the Littoral region in Cameroon recorded more than 5,000 cases of tuberculosis representing a quarter of the total number of TB patients in in the country. The application of measures to control TB infection and the regular surveillance of tuberculosis disease among health workers and at all levels of the health system constitute a public health priority, not only for health and administrative workers, but also for all users. This study assessed the adherence to preventive measures against TB by health workers of the diagnostic and treatment centers in the city of Douala. Methodology: This is a descriptive cross-sectional study carried out among health workers from 12 TB screening and treatment centers in the city of Douala. It took place from July 20, 2020 to August 15, 2020. The data were collected using an observation grid designed on the basis of the technical guidelines for health professionals 4th Edition set up by the WHO and contextualized in Cameroon through the technical guidelines for health professionals in Cameroon 2020. The data collected was analyzed using the statistical software Epi Info 7.2.3.1. Results: The implementation of preventive measures (administrative, environmental and individual) against TB by health workers in the diagnostic and treatment centers in the city of Douala was insufficient with the respective adherence average of 79.16% for management measures, 71.80% for environmental measures and 54.76% for individual protection measures. Conclusion: The poor implementation of infection control measures in the TB diagnostic and treatment centers in the city of Douala can promote exposure of health workers to Mycobacterium tuberculosis. An institutional effort required to resolve this issue and strengthen TB prevention activities.


Introduction
Tuberculosis (TB) is one of the top 10 causes of death in the world. It is also the main cause of deaths related to antimicrobial resistance and the leading cause of death among people living with the Human Immunodeficiency Virus (HIV)/Acquired Immunodeficiency Syndrome (AIDS). In 2019, 10 million people contracted TB, and 1.4 million people died from the disease (of which 208,000 also had the HIV infection), while in 2016, of the same estimated cases, only 6.3 million (61%) were detected and put on treatment [1,2]. TB is an infectious and contagious disease transmitted through air; with variable clinical signs and caused by the bacteria Mycobacterium tuberculosis. Contamination occurs through infected droplets from the patient's lungs. These fine droplets are produced when the patient coughs or sneezes. These particles inhaled by a healthy subject can reach the pulmonary alveoli and cause TB infection [3]. Infection is more likely to occur when a person is exposed to a patient with pulmonary TB on a daily basis, for example by living or working close to a person with an active disease [4].
Studies in some African countries and other parts of the world have shown that health workers are considered to have a higher risk of infection with Mycobacterium tuberculosis than the general population [5]. It is therefore important to take measures to protect healthcare workers working in a context of the spread of TB. Although these measures have been enacted, their application still remains a major challenge. TB remains a major health problem, especially in Africa and more particularly in sub-Saharan countries [6]. Although several research have been carried out in Cameroon on TB [6,7,8,9,10], there is however a paucity of information on the implementation of preventive measures against TB by health workers in diagnostic and treatment centers in the country. This study therefore seeks to assess the adherence to preventive measures against TB by the health workers of diagnostic and treatment centers in the city of Douala, the cosmopolitan capital of the Littoral region of the country.

Methods
A descriptive cross-sectional study was carried out in 12 TB diagnostic and treatment centers in the city of Douala:

Administrative management of DCTs
Seventy five per cent (9/12) of DTCs the city of Douala early identify TB suspects through the criteria, while 3/12 (25%) of these centers do not. Half (6/12) of DTCs separate the suspected or confirmed cases from the other patients while the other half group together all the patients in the same hall. Up to 11 (91%) of the 12 DTCs favor the administration of outpatient treatment for the first 2 months rather than hospitalization. All the 12 DTCs report diagnosed TB cases through the data collection tools of the health information system such as laboratory registers and / or TB registers (Table 1). In 11 DTCs, that is 92%, the staff sterilize all the hardware instruments after use, using the autoclave for some and / or oven for others. In a DTC, staff do not sterilize equipment after use and sometimes leave it in the decontamination solution for hours. Equally, in 11/12 (92%) DTCs, the disinfection of work surfaces is carried Page 4 on 11 out using tuberculoicidal products such as chlorine. Eighty three per cent (10/12) of DTCs have protocols related to sensitizing staff on preventive measures against TB through picture boxes and posters for others (Table II).

Protective measures by health care workers in the DCTs
Of the 12 DCTs evaluated, only in 2(17%) health workers correctly wear particulate respirators, specifically

Discussion
Our study focusing the adherence to preventive measures against TB by the health workers in the DTCs of Douala, is in line with other studies carried out by several authors [12,13,14], aiming to assess the implementation of administrative, environmental and respiratory protection control measures against TB infection. Our results corroborate with the studies carried out in Japan [12], Portugal [13] and Colombia [14]. The World Health Organization (WHO) guidelines [15], the Center for Disease Control and Prevention (CDC) [16] and Cameroon [11] have proposed the implementation of measures to control TB infection at three levels: administrative, environmental and personal respiratory protection. In the Infection Prevention Control (IPC) TB strategy, administrative controls are the cornerstone and first priority, while the other two are entirely dependent on administrative control for their effectiveness [17].

Administrative control measures
According to the results of our study, half of the DTCs separate the suspected or confirmed cases of other patients which is in line with a study conducted in Mongolia in 2011 in which 23% of health facilities separated patients suspected of TB [18]. Equally, one study showed that less than half (46%) of designated TB hospitals had a separate waiting area for patients. When TB patients and other facility users share the same overcrowded and poorly ventilated waiting area, unnecessarily long waiting times in the process of diagnosis and treatment can increase nosocomial transmission of TB [19]. In a study carried out in Uganda, it was also found that patients who were coughing were not prioritized for outpatient services in over 90% of facilities. They were observed waiting in the same area with other patients for long hours in queues [20]. The staff therefore said to this effect: "It is   [ 21]. Also in South Africa, a study in 2015 revealed that no establishment in Ugu district had reported separating patients suspected of having TB from other patients [22].
All DTCs notified diagnosed TB cases through health information system data collection tools such as laboratory registers and / or TB registers. This percentage is contrary to that obtained in a study carried out in China in which the results are generally kept by individual workers rather than the employer, especially in small hospitals. Also, negative results are often not recorded. Moreover, these recordings are generally not systematically reported to the national TB control program (NTP) or to the occupational health authorities [23]. According to a study carried out in China, the implementation of TB infection control and reporting of TB cases are both fragmented, due to the wide margin of appreciation enjoyed by Chinese hospitals and local organizations [24]. The mean adhesion to Administrative measures by the health workers of the DTCs was 79.16 %. This is contrary to a South African study in which the levels of implementation of administrative measures for TB were less than 20.0%. This is a huge pitfall, as these measures should be implemented from the first contact with a patient in a healthcare facility.
Delays in screening, diagnosis and treatment for TB due to failure to implement these checks increase the risk of health care-related illnesses. Administrative measures for the control of TB infection should be the first pillar and should be given greater recognition in the context of the study setting. In the absence of appropriate infection control practices, healthcare associated infections will inevitably remain a risk [17].

Environmental control measures
Environmental control measures (second priority) depend on the design of infrastructure, use of ventilation and irradiation, all of which require capital investment. However, effective methods have been proposed based on ventilation through window openings [17].  [17]. These external climatic conditions, as well as the individual perceptions of the workers concerning the cold or the heat and opening of the various services (medical and surgical unit) were mentioned in a study carried out in Colombia [14]. Natural ventilation, such as through windows and open doors, is efficient and less expensive for air circulation as shown in up to 67% of DTCs laboratories in our study with good natural ventilation which corroborates a Chinese study in which the natural ventilation of TB services was observed in 89% of hospitals [19]. Nonetheless, 33% of DTCs in our study do not have access to sunlight or sufficient passage of outdoor air. Ventilation is a vital measure of environmental control. Although natural and mechanical ventilation methods were present in most of the hospitals designated for TB in the present study, regular monitoring of ventilation (at least quarterly) for the control of TB infection was carried out in only 57 % of hospitals surveyed, indicating that many did not sufficiently cater for maintenance, thereby increasing the risk of healthcare workers to infection. [19]. DTCs, health workers collect sputum externally, while only one DTC does so directly in the laboratory. This is in line with a study in which 6% of hospitals took sputum samples outside the hospital building [19]. In addition, WHO guidelines recommend that sputum collection be done outdoors, away from other people or in wellventilated areas [15]. The majority (87%) of DTCs in our study use a solution for decontamination of equipment made mostly of chlorine and changed every 24 hours, which corroborates with the results of a Chinese study in which 96% of hospitals disinfect the sputum collection area and medical equipment daily [19].

Individual protection measures
Personal respiratory protection is the third and final recommended barrier to protect healthcare workers against inhalation of infectious droplets [11]. In 17% of DTCs, health workers correctly wear particulate respirators precisely FFP2 and N95, which have an efficiency of 95% minimum filtration for particles of 0.3 micron in diameter [12]. Eighty-three percent of DTCs do not have one due to shortage in stock as a result to the Covid-19 pandemic. A study carried out in South Africa showed that only 38.8% of the staff used the N95 breathing apparatus [17]. The unavailability of respiratory protective equipment could limit their use in hospital. Several other studies have shown that very few health workers regularly wear personal respirators when evaluating patients for TB as in China [23], or South Africa with a percentage use of masks of 22% in hospitals by staff [25].
The result of our study also corroborates with another in South Africa in which 40% of hospital facilities lacked masks and disposable respirators [22]; as well as that of Malangu still in South Africa where only 22% clinics had N95 masks available for staff [21]. In the same line, a study in Brazil indicated that adherence to the use of the N95 mask is not very well established among healthcare professionals, resulting in low compliance [26]. Thus, according to a study in Russia, the quality of the N95 mask, the discomfort and the neglect of its importance are factors of non-adherence to its use [27]. However, other studies are in contrast to the previous ones evoking the availability of protective masks such as that of Sousa in Portugal in which the health workers used protective respiratory equipment (92%) [13] and Chen where most (97%) hospitals provided N95 respirators for health workers [19]. Our study shows that in most DTCs, healthcare workers use surgical masks for the prevention of TB that do not filter the nuclei of infectious droplets [14]. This result is in line with a study carried out in Colombia in which the institution was permanently making surgical masks available to the health workers for their protection [14]. Also in Uganda, health workers wore only surgical masks for protection [20]. In 92% of DTCs, health workers exclusively wear coats with long sleeves in the microbiology laboratory which is contrary to of a study carried out recently in South Africa where only 19% of the staff wore recommended coats [25]. In 17% of the DTCs, the health workers present atypical signs of TB such as cough. This is certainly due to the lack of screening among health workers and corroborates with a study carried out in Japan in which many establishments did not verify the presence of fever and / or respiratory symptoms [12].

Declarations Ethical approval and consent to participate
This study was approved by the institutional ethical committee of the University of Douala, located in the city where the study was carried out. Also, research authorizations were obtained from the Regional Technical Group for Tuberculosis in the Littoral region and the various officials of the Tuberculosis Diagnostic and Treatment Centers in Douala. Informed consent of all participants was obtained. All methods were performed in accordance with the relevant guidelines and regulations/declaration of Helsinki.