Tuberculosis (TB) remains a major public health problem throughout the world [1, 2]. About one-third of the world’s population is estimated to be infected with the bacilli and become at risk of developing active TB infection [2]. In 2014, about 9.6 million new TB cases and over 1.5 million deaths from the diseases were reported; 95% of these deaths occurred in low and middle income countries. Africa is the region with the most burden of TB cases with an estimated prevalence of 281 all forms of TB cases per 100,000 inhabitants which is doubled of the global average of 133 cases per 100,000 [3, 4]. According to the global tuberculosis report most countries shows progress in reducing the burden of tuberculosis though it is not as targeted by the millennium development goal. Considering this unmet target and to transform the world, the international community develops a new agenda of ending TB epidemic by 2030 in the newly adopted Sustainable Development Goals [5].

Effective TB control program through early diagnosis and treatment is an essential strategy to decrease the burden of the disease [2, 6]. Most of the risk of TB infection occurs between the contacts of the infectious cases and before the initiation of treatment [7–10]. Early screening of presumptive TB cases starting at the community, providing rapid diagnosis, and treating the cases early at health facilities reduces the risk of disease transmission as a result the reduction of time between the onset of symptoms and the initiation of treatment [2, 11]. Thus individuals who had cough for two weeks or more are requested to go to health facilities for diagnosis and early treatment [12]. As one of the major tools to diagnose tuberculosis, direct microscopy is not only cost effective but also simple and capable of producing reliable result, within two consecutive days [13–15]. The National (Ethiopia) TB Control Program recommends collecting three sputum specimens for pulmonary TB (PTB), and that individual who have at least two smear positive results or a single smear positive result supported by radiographic abnormalities be classified as pulmonary smear positive (PTB⁺). While those with three initial smears negative examinations but showed major symptoms of TB are confirmed by gene-xpert or culture [16, 17]. However this, low case detection rate (CDR) in most nations resulting from patients’ inability to seek health care at the onset of symptoms and the delay of diagnosis and treatment remain a challenge in TB control programs [3, 13, 18, 19].

Delays in seeking health care and in providing early diagnosis and treatment increases the risk of disease transmission, and subsequently leads to death. TB diagnosis and treatment are delayed when patients wait until long after the onset of symptom to seek care (patient delay), or when care providers take too long to diagnose and treat the patients who sought care (health system delay) [14]. The length of delay was significantly longer among low and middle income countries than in the developed nations. The longest total delay in TB diagnosis and treatment was noted in Afghanistan (356.0 days) [20]. In most studies conducted elsewhere, it was noted that patient delay was longer than health system delay [20–22]. A cross-sectional study among smear positive pulmonary TB patients in Afghanistan reported that patient delay (205 days) was longer than health system delay (151 days). In Nigeria, the median total delay, patient delay, and health system delay was 11, 8, and 3 weeks, respectively [21]. In Angola, the median total time that elapsed from the onset of symptoms to diagnosis was 45 days,while the median patient delay and health system delay was 30 and 7 days, respectively [22]. A cross sectional study in Chad reported that the median patient delay, system delay, and total delay were 15, 36, and 57.5 days, respectively [23]. In Ethiopia, though there are regional variations in total delay in TB diagnosis and treatment, it generally ranged from 40–97 days [8, 24–28]. As demonstrated by various reports, delay in diagnosis and treatment is found to be affected by various factors, but it is mainly related to patients’ health care seeking behavior and health system provision of prompt diagnosis and treatment [22, 25, 29, 30]. Among the various factors reported, residence [22, 26], type of health facility [22], and seeking care from other than health care providers [29–31] were associated with the delay for TB diagnosis and treatment.

Ethiopia ranks 10th among 22 high TB burden countries (HBCs) and the disease remains one of the leading causes of mortality and morbidity. According to the 2014 WHO report, the incidence and prevalence of all forms of TB cases were 224 and 211 per 100,000 populations, respectively. Though there has been some achievement in the process of reducing the incidence of tuberculosis as targeted in the Millennium Development Goal (MDG),, still one-third of the suspected cases are not detected and continue a source of TB infection [32, 33]. Therefore, to determine the length of delay in seeking health care, early diagnosis and initiation of treatment can improve the detection rate and will have further role in the success of TB control programs.

Ending TB epidemic by 2030 is among the health targets of the newly adopted Sustainable Development Goals [5]. Cognizant of this initiative, early detection and prompt treatment of cases is the main strategy to reduce disease morbidity and mortality throughout the world [11]. In this study, total delay, patient and health system delays were measured to assess the length of delay in diagnosis and treatment.

In this study, mean total days of delay of TB diagnosis and treatment was 41.6 days (SD: 16.6). Out of the total 41.6 days of delay of diagnosis and treatment, the bulk of the days (33.9) of delay were patient delays. The length of delay in the health system of diagnosis and treatment was 5 days, which was significantly shorter than the patient delay. This reflects seeking health care for TB diagnosis and treatment takes longer time when compared with length of stay in the health system. In addition, it suggests that effort to increase awareness of the community to enhance seeking care to health care.

The total days of delay of TB diagnosis and treatment in this study (41.6 days) was in line with the studies conducted in Iraq (45 days) [37], and in Arsi Zone, Ethiopia (40 days) [8]. However, in this study total delay was lower than those of in studies in different regions of Ethiopia, Bale zone (97 days) [24], Afar (70.5 days) [25], Bahirdar (60 days) [26], Tigray (90 days), and East Wollega (90 days) [27, 28], and it was also lower than the findings of studies conducted in Nepal (50 days) [38], West Africa (60 days) [9], and Tanzania (120 days) [10]. The lower delay seen in this study compared with other studies might be that the majority of the participants of this study were urban dwellers who had access to better health care facilities, and the recent implementation of the Urban Health Extension Program in the study area. This suggests that effort should be made to expand and sustain these health care facilities in achieving the sustainable development goals and universal health coverage.

The finding revealed that the mean patient delay (standard deviation) was 33.9 (SD: 14) days. This finding was consistent with those of studies conducted in Ethiopia, for example Arsi Zone (22 days) [8], and Southern Ethiopia (30 days) [39], Tanzania and Zimbabwe (28 days each) [10, 40], Sudan (27 days) [41], and Thailand (30 days) [42], but it was longer than that of study conducted at Bahir Dar (21 days) [26]. On the other hand, the median health system delay (IQR) was 5 days (4–7). This finding was consistent with a report from Yemen (4 days) [37] and Arsi Zone (6 days) [8]. However, it was longer than the report from Zimbabwe (2 days) [40]. The longer health system delay in this study might be due to the turnover of experienced staff and the efficiency of health care professionals in identifying suspected cases [1, 43, 44]. Furthermore, shortage of resources of the TB control programs which was faced in most health facilities might be the reason for longer health system delays in TB diagnosis and treatment [45, 46].

Among factors which had significant associations with patient delays, patient delays among rural residents were longer by 8 days compared with urban residents. Consistent with studies elsewhere [28, 41, 47, 48], long delays among rural residents might be the inaccessibility of health care facilities. Similarly, the length of patient delay was longer among respondents who sought health care from informal care providers, which was consistent with studies conducted in Afar [25], Arsi Zone [8], and Uzbekistan [49]. In countries like Ethiopia where there are various traditional practices and poor access to quality health care, patient sough care from informal health care provider; as a result the patients might have been given inappropriate care which led to several other visits before reaching the appropriate health facility for TB care. In contrast, shorter patient delay was noted among HIV positive individuals compared with HIV negative ones. This association was similar with those of studies in Bahir Dar, Ethiopia [26], and Mozambique [31]. This might be due to the collaborative TB/HIV activities existing in the health institution which ensures early TB screening among HIV patients and vice versa [50]. In addition, strict follow-up of health care providers for HIV positive individuals might be the reason for shorter delay in seeking health care for TB diagnosis and treatment.

A shorter patient delay was reported among individuals with increased household income, which was consistent with a finding in Sudan [41]. This might be due to the role of income in enhancing the chance of seeking health care. Consistent with studies conducted elsewhere [8, 24, 40, 51], a longer health system delay was noted among individuals who seek care from more than one health care providers. Similarly, the length of health system delay was longer among individuals who sought initial care from primary level health facilities which was similar with those of studies conducted in Nigeria [21] and different regions of Ethiopia, like Arsi Zone, Bahir Dar, and Bale zone [8, 24, 26].

As a limitation, recalling the exact date of the onset of symptoms and the date of visits to health facilities might under or overestimate the delay. However, to minimize such bias reviews of medical records, national holidays, religious days, and dates of some events were put to use. The other limitation of this study, patient related factors in the health system delay, was not assessed.

The delay of tuberculosis diagnosis and treatment in this study was longer than the national recommendation of two weeks (14 days). Seeking health care for diagnosis was responsible for longer delays. Longer delay of TB diagnosis and treatment were noted among rural residents, patients who sought health care from informal care providers, and those who received initial care from primary level health care facilities. In contrast, the delay of TB diagnosis and treatment was shorter among HIV positive people and individuals with increased household income. Therefore, public awareness on the symptoms of tuberculosis and seeking early care is essential. Moreover, early detection, follow-up, and initiation of TB treatment among people living in rural areas and among the poor should be focused on.