One of the United Nations’ Sustainable Development Goals (SDG) as contained in the SDG target 3.3 is to end the tuberculosis epidemic by the year 2030. This End TB Strategy defines as a targets for 2030, a 90% reduction in the number of TB deaths and an 80% reduction in the TB incidence rate (new cases per 100 000 population per year) compared with levels in 2015. ¹ Progress in global TB elimination which has been inconsistent in recent years has led to intensified efforts to improve TB diagnosis, treatment, and prevention required to meet global targets for 2020–2035. ² To achieve these set targets, there’s a need for various national tuberculosis programs to have agendas set and implemented towards meeting goals. In 2019 alone, an estimated 1.4 million people died from TB-related illnesses and of the estimated 10 million cases that year, some 3 million went undiagnosed, or were not officially reported to national authorities. ³

Diagnosis, treatment and prevention of tuberculosis rests largely on the healthcare workers. Health care workers knowledge and attitude with respect to diagnosis, treatment and prevention of TB is vital in TB elimination. ⁴ In Nigeria, the treatment of TB is free at all public health facilities. Successful implementation of directly observed treatment short course (DOTS) is dependent on the ability of the health care system to identify and properly manage TB cases which requires active involvement of the health workers in TB diagnosis and management. TB treatment should include counselling regarding progression of disease and the importance of treatment adherence. ⁵

Countries with good TB knowledge scores have been shown to have better TB indices with respect to treatment and prevention. In Iran, 98.4% of healthcare workers had a 'good' score for knowledge of TB with 98.2% who correctly answered that TB transmission is through the respiratory tract, 90% acknowledged TB is a treatable disease, and only 12.6% of them were oblivious that it is caused by a bacterium. ⁶ In South India, accurate knowledge of TB was displayed by 86% of healthcare workers. ⁷ Good and fair level of knowledge of TB was possessed by 56% and 43.9% of healthcare workers in Thailand. ⁸ Studies in South Africa and Mozambique also reported satisfactory level of knowledge of TB among health care workers. ^{4 , 9} In Mozambique, higher knowledge scores were seen among those with greater educational attainment. Knowledge scores were also affected by profession with medical doctors having the greatest knowledge score and midwives having the lowest knowledge scores. ⁴

A study in Vietnam also showed that an increased level of TB knowledge among the health staff is correlated with participation in TB training and higher medical education. ¹⁰ In South Africa, the mean percentage of correct answers to the 98-item questionnaire administered was 59.5% pre-training and rose to 66.5% after training. Post-training, nurses, doctors and TB support staff showed significant improvements in total mean knowledge scores. ¹¹ A study in China that assessed knowledge retention of multidrug-resistant tuberculosis (MDR-TB) health practitioners 1 year after training, reported an overall positive long-term impact of the training on participants’ knowledge. ¹² Akande et al., in a study in Nigeria reported a significant increase in the knowledge of TB infection control after the health workers had been trained. ¹³

Training of frontline health workers is an important strategy for TB control as efficient human resources development is crucial for facilitating tuberculosis control. In an ideal setting, training on TB should be integrated into the general education of health workers and into health systems. However, in a tuberculosis-endemic and resource-poor country like Nigeria, these systems are too weak to support routine effective tuberculosis control and training services. ¹⁴ This study therefore aims to determine the effect of TB training on the knowledge of community health workers in Akwa Ibom state. This will aid in policy making and program designing with regard to TB control in the state.

This study was registered as a clinical trial with the Pan African Clinical Trial Registry (PACTR202010691865364 on 14 ^th October 2020). This article is reported in line with the Consolidated Standards of Reporting Trials (CONSORT) guidelines. ²⁷

A total of 240 CHWs were recruited at baseline and 153 trained, 85 in arm A and 73 in arm B, while 82 were recruited in the control arm ²⁶ . At the end of the trial 72, 77 and 72 were analysed in arms A, B and C, respectively, to give a total of 221. Over the 12-month period of intervention, some CHWs retired, relocated and transferred out of the catchment area.

Most of the CHWs in this study were female (62.5%), aged 30 years or less (47.9%), and had secondary level of education (64.6%). PMVs made up the majority of the health workers (78.8%), and over half (69.2%) worked at patent medicine shops. Most had worked at their current position for 1-4 years (32.1%). There was statistically significant difference in the duration at current position (P = 0.035) and type of facility of CHWs (P = 0.000) across the three arms. Also, a significantly higher proportion of CHWs in the control group (43.9%) had previously attended a TB workshop and had access to TB guidelines (31.7%) compared to their counterparts in other groups ( Table 1).

Table 2 shows the sociodemographic characteristics across the three arms post-intervention. Most participants were aged 31-40 years (44.3%), female (53.4%), had secondary level of education (64.3%) and had worked for 1-4 years at their current position (38.0%). The majority were PMVs (77.4%), and worked at patent medicine stores (52.9%). There was a statistically significant difference in the duration of current job of the CHWs across the three arms ( P 0.006), and in the type of health facility across the three arms ( P 0.001).

There was a significant increase in the total knowledge score of the respondents at end line ( P 0.0001), with the respondents at baseline having a mean knowledge score of 11.8 (3.2) and at end line 16.8 (2.5). There was also statistically significant difference in the different categories of knowledge tested at baseline and at end line ( Table 3).

Table 4 compares the knowledge of tuberculosis across the three arms of the study. There was statistically significant relationship seen between respondents’ knowledge of diagnosis ( P 0.0001), knowledge of prevention ( P 0.014) and the total knowledge score ( P 0.0480); and the different study arms.

Post-intervention, a higher proportion of the respondents in the control group had good knowledge of diagnosis and treatment (75%) and prevention (93.1%) compared to the training and cash incentives group (55.6% and 76.4%, respectively). These were statistically significant at P 0.0224 and 0.0096 respectively ( Table 5).

At endline, a higher proportion of the respondents in the control group had good knowledge of diagnosis and treatment (75%) and prevention (93.1%) compared to the training only group (42.9% and 77.1%, respectively). These were statistically significant at p=0.0109 and 0.0001, respectively ( Table 6).

At baseline, CHWs who were in the training and CCT arm had a mean total knowledge score of 13.8 (2.4), and at end line, 14.5 (2.1), and this difference was statistically significant ( P 0.0001). The difference in mean general knowledge score at pre- and post-intervention was also statistically significant ( P 0.0430) ( Table 7).

Table 8 shows the knowledge score of the health care workers that were in the training only arm at baseline and at endline. The mean general knowledge score, prevention score and total knowledge score showed a statistically significant increase at the end of the study compared to baseline ( P 0.0001, 0.0353 and 0.0001, respectively.)

In the control arm, the mean total knowledge score increased by 2.1 (95% CI:1.3-2.9) at endline, and this increase was statistically significant ( P 0.0001). Significant increases were also noticed in the different categories of knowledge assessed for at endline compared to baseline ( Table 9).

This randomized control trial aimed to assess the effect of tuberculosis training on community health workers knowledge on TB in Akwa Ibom state. Overall, there was improvement in the respondents’ knowledge post-intervention, compared to the baseline knowledge. The CHWs were comparable in their socio-demographic characteristics at baseline and at endline. It is worthy of note that a significant proportion of CHWs in the control arm had previously received training on TB, and had access to TB guidelines. This may be due to the attention the state has been receiving as a result of the high prevalence of HIV/AIDS, and consequently TB.

This study found a significant increase in CHW’s TB knowledge post intervention when compared to the baseline. The highest increase was noticed in knowledge of prevention, followed by knowledge of general symptoms. At baseline, the mean knowledge score of the CHWs was just above the average, increasing by a score of three at end line assessment. This corroborates with others studies that found an increase in knowledge of TB immediately after training and even long after training was done. ^{13 , 18 , 19} Training was found in Abia state, Nigeria, to not only improve knowledge among Health workers, but to also improve all indicators of the Finding TB cases Actively, Separating safely, and Treating effectively (FAST) strategy which include the time to diagnosis (the time between when patient presents to the health facility to when a diagnosis of TB is made), time to treatment which the time between making a diagnosis and commencement of TB treatment, number of presumptive TB and Drug Resistant TB (DRTB) cases identified and number of TB and DRTB cases commenced on treatment. ²⁰

Comparing the three arms of the study post-intervention, it was observed that knowledge of diagnosis, prevention and the total knowledge score was significantly different across the three arms. Furthermore, the control arm was seen to have a higher mean knowledge score when compared to the arms that received training. This may have been an effect of previous training that the health workers in the control arm had received, as well as the fact that they reported having more access to TB guidelines. In a similar study among HIV infected people in Minna, training was shown to significantly improve the knowledge of the participants in the intervention group compared to the control group. ²¹ In contrast, a similar study by Rakhshani et al. reported a significant increase in end line knowledge of malaria in the intervention group when compared to the control group. ²² More participants from the training and cash incentives arm in the present study however had good knowledge scores when compared with those in the control arm, though this finding was not statistically significant.

This study compared the knowledge of CHWs in each arm at baseline and at endline. Among the participants in the training and cash incentives arm and in the training only arm, there was a significant increase in the mean total score between the baseline and post intervention. This is similar to results obtained in Turkey where training intervention increased the primary healthcare workers’ knowledge on immunization. Furthermore, the study reported a significant increase in the vaccination coverage rate in the community after the training intervention. ²³ Training intervention is therefore be effective in increasing knowledge and effecting behavior change. This is corroborated by other studies. ^{21 , 22}

Training community health workers on TB is essential to achieving TB control as they are the frontline health workers in the communities and are at a better position to identify TB cases. In a study in Southern Mozambique, health workers were seen to have poor knowledge of TB, and consequently low practice competency. ²⁴ Wu et al. found a decline in health workers knowledge one year post intervention, compared to the immediate post intervention period, though it was still higher than the pre-intervention knowledge. ¹⁸ This therefore implies that training of health care workers should not be a one-time event, but a continuous process if TB control is to be achieved. Experiences in Kyrgyzstan ¹⁴ and the Democratic Republic of Congo show that periodic training and supervision in the field can improve healthcare workers’ TB knowledge and skills. ²⁵

This study had some limitations. Firstly, though this study was planned as a panel survey, this could not be carried out. This is because some of health workers in the different communities may have resigned or moved away, while others took up these positions. Therefore, not all those that were trained at baseline could participate in the post intervention assessment. Also, a few CHWs were transferred in and were part of the post intervention assessment since it was a cluster sampling.

Another limitation was the selection bias seen in the study. The control arm had more exposure to TB training as evidenced by the baseline characteristics like exposure to workshops and access to TB guidelines were significantly higher among the control group. The control arm was likely to have had previous trainings on TB and had access to TB guidelines which may have affected the study results. This is because random allocation of PHCs to the different arms was carried out prior to pre-intervention assessment.

This study was conducted to determine the effect of TB training on the knowledge of community health workers in Akwa Ibom state, Nigeria. Patent Medicine Vendors formed two thirds of the CHWs mobilized, indicating they were readily available in the communities. We found a significant improvement in the CHWs knowledge of symptoms, prevention, diagnosis and treatment of TB after the training intervention was done. We thus recommend the integration and use of PMVs in the delivery of interventions in the community. Furthermore, integration of routine TB training for all categories of CHWs will improve TB case finding and notification, improving TB indices in the communities and the country.