Tuberculosis (TB) is a public health problem that affects millions of people worldwide1 especially in sub-Saharan Africa where the burden of TB is greater.2 For an effective TB control program it is essential to obtain early diagnosis, immediately begin appropriate treatment and ensure its continuity.3

Time delay in the diagnosis of TB plays an important role in the increase of infectivity, mortality risk and transmission of the disease in the community.4,5 It is estimated that an untreated patient with positive microscopy for TB bacillus can infect, on average, 10–15 community contacts within a year.6

The factors that contribute to the time delay in the diagnosis and treatment of TB may be related to the patient himself as well as the healthcare service.7–12 Sex, age, educational level, occupation, distance from home to the healthcare institution, co-morbidities and poor knowledge about TB, were some of the factors related to the patient.13–16 Lack of diagnosis resources, such as chest radiology, negative microscopy result, waiting time and the first healthcare unit consulted were associated to the system delay.8,10,15–17

In Angola, TB is one of the main reasons for visits to healthcare services. In 2015, the incidence of TB was 93 per 100,000 inhabitants.18 In 1981, the Angolan Ministry of Health established the National Tuberculosis Program (NTP), whose priority was the establishment of TB diagnosis and treatment services throughout the country.8 Huambo province is located on the central plateau of Angola, with an area of 35,771km2 and 2,019,555 inhabitants, corresponding to 7.8% of the total population of the country, according to the final results of the population census of 2014.19 The province's healthcare network consists of 11 municipal hospitals, 1 General/Provincial hospital, 1 Sanatorium hospital, 1 Anti-Tuberculosis Dispensary (ATD), 50 healthcare centers and 165 health posts (report from the provincial directorate of health, 2016). For the diagnosis and treatment of TB, the province has 12 outpatient units, some of which are linked to municipal hospitals. In these units, pulmonary TB diagnosis is based on sputum microscopy performed on three patient-provided samples, clinical history and chest radiography. For extrapulmonary TB (EPTB), the diagnosis is based on microscopy of biological products depending on the infected organ or only on the symptoms of the disease, the clinical history and the radiography, at the doctor's discretion. Patients with criteria for hospitalization due to complications of TB or requiring further intervention are referred to the sanatorium hospital, since it is the reference unit. Patients without criteria for hospitalization are directed to the ATD. Treatment is provided under directly observed treatment (DOT) during the intensive phase. In the maintenance phase, the patient is entrusted to a relative.

The Sanatorium hospital, with its ambulatory dependency ATD, is considered the reference center for TB in the region. The Sanatorium Hospital/ATD possesses a bacteriology laboratory for microscopy exams and a radiology section.

The Huambo province has a regional mycobacteriology laboratory that performs culture tests and antibiotic sensitivity tests (TSA) in the case of a negative microscopy, therapeutic failures or resistance to antibiotics in the Central South region.

The purpose of this study was to identify the factors associated with TB diagnosis delay in the population of Huambo, Angola.

Of the 353 respondents, 247 patients were included in this study. Their median age was 27 years old, 159 (64%) were males, 197 (80%) had irregular occupations, 136 (55%) had a household size of 5–8 people, 151 (57%) patients did not consume alcoholic beverages and 204 (83%) did not smoke (Table 1).

The median diagnosis delay was 64 days (IQR: 37–95 days).

In the univariate analysis, living outside of Huambo (p=0.006), being aged between 15 and 29 (p=0.035) or 30–44 (p=0.005), consuming alcoholic beverages (p=0.039) and living in a residence more than 10km from a healthcare unit (p=0.001) were associated with longer diagnosis delay. Using the emergency unit as a reference, it was found that the patients who first sought out any other healthcare unit took more time until diagnosis (p≤0.014) (Table 1).

The multivariate analysis model indicated that individuals aged between 30 and 44 years (p=0.018), living at a distance greater than 10km from a healthcare unit (p=0.006), and not going to the emergency unit, especially if they first used traditional medicine (p<0.001), had longer diagnosis delay (Table 2).

One hundred and six patients were excluded from the analysis because they did not know the date of the onset of their symptoms, which meant that the time delay until the diagnosis could not be calculated. The median age of these patients was 25 years and 75 (71%) were male. Excluded patients differed from the included ones especially in tobacco use (lower proportion of non-smokers, p=0.005), qualifications (higher proportion of illiterate and primary educated, p<0.001) and the first healthcare unit sought (higher proportion of Health Center and Emergency Service, p<0.001).

In this study the time delay of 247 diagnosed patients at the Huambo ATD, between October 2015 and January 2016 was evaluated.

The median diagnosis delay was 64 days. Our findings do not differ from other studies in Nepal,21 Ethiopia,10 India,12 Yemen,22 and Zambia23 where the median delay was 60–63 days. On the other hand, Tanzania24 had a considerably longer median time of 136 days and Portugal25 a shorter one of 36 days. A previous study conducted in Luanda, Angola, had a median diagnosis delay of 45 days.8 The factors associated with delaying the diagnosis of TB may be different between Huambo and Luanda, considering the greater concentration of the population in the country's capital (72% living in urban area).

In the univariate analysis, we found that living outside of Huambo city, being between 15 and 29 or 30–44, consuming alcoholic beverages, living in a residence more than 10km from a healthcare unit and seeking health care outside of the emergency service system were associated with longer diagnosis delay.

Based on the multivariate analysis results encountered, belonging to the 30–44 years old age group was associated with a longer time delay until diagnosis. Age has been associated with diagnosis delay in other studies.9,10,14–16,24,25 Several social factors such as work schedule and difficulty in organizing working time to visit healthcare services have been given as explanations for a greater delay in this age group.15

Regarding the distance to the healthcare service, in the studies carried out in Ethiopia and Tanzania, the patients who lived more than 10km away from the healthcare institutions had a longer time delay until the diagnosis of TB, when compared to those living within a 10km radius.17,24 Other studies have found a relationship between longer walking distance to a healthcare facility and patient delay in Nepal,14 Nigeria,16 Odisha, India11 and south India.12 These studies corroborate our findings, in which the distance from the healthcare service was considered a factor in diagnosis delay due to unavailability and lack of access to TB diagnosis and treatment units in rural areas.

The first healthcare service consulted was identified as the risk factor for longest delay until diagnosis, particularly if it was a private clinic or a traditional healer. Though most patients (78.9%) lived in the Huambo municipality, we cannot say whether the demand for these units is attributable to patients living in rural or urban areas. Although the number of patients that consulted the health center (17%) and traditional healer (5%) is low, there is a longer delay time. Similar results were also verified in the previous study in Luanda. This was also confirmed in previous studies, where longer diagnosis delays were obtained when private healthcare facilities and traditional healers,11,12,17,24,26 were the first healthcare unit used. On the other hand, in the Huambo province, poor availability and accessibility of the primary health care, lack of public transport for some communities and socioeconomic conditions of the patients can be considered in the diagnosis delay.

Our study had some limitations. It was performed in an area with insufficient resources. Patients who appeared at the weekend were not questioned. Other limitations of our study were mainly related to the exclusion of the population that did not remember the date of the onset of their symptoms. However, despite the fact that the excluded patients differ in their smoking habits, literary qualifications and first healthcare unit used, there were no differences between the two groups in any of the other analyzed variables that were significant in the diagnosis delay. We cannot exclude memory bias in the responses. We assume that the delay time was calculated based on the dates declared by the patients, which may have been subject to error.

Despite the limitations presented, the strengths of this study are relevant. The study was carried out in the reference unit that covers the region, with good adherence and it is the first study on TB diagnosis delay in the Huambo province.

In the Huambo province, age, distance to healthcare units and the first healthcare service used were associated with tuberculosis diagnosis delay. To reduce delays and improve access to health care, efforts should be made to expand public health institutions in rural communities, to decentralize health services. The government, via Ministry of Health, should create policies involving the private sector in TB care. This will provide a key basis for TB control and health coverage for people living in areas of poor access. The community should also be informed on how to recognize the symptoms of TB through lectures, and healthcare professionals should be better trained, in order to reduce the patient's delay time until diagnosis and initiate treatment as early as possible, interrupting TB transmission.27 Although sputum microscopy is the favoured method used in the province, new diagnostic techniques like Xpert MTB/Rifampin should be implemented, because they contribute to the rapid diagnosis and effective detection of TB disease and drug resistance.28,29

The authors have no conflicts of interest to declare.