A retrospective study on the epidemiology and trends of road traffic accidents, fatalities and injuries in three Municipalities of Dar es Salaam Region, Tanzania between 2014-2018

Introduction Over 90% of injuries and deaths still occur in low and middle-income countries like Tanzania due to Road traffic accidents. Available literature indicates that Tanzania suffers massive human and economic losses every year from RTAs despite several interventions that have been made to curb this scourge. To gain an insight into the current state of RTAs we examined the pre- historical case fatality rates from RTAs in Ilala and two other municipalities (Kinondoni and Temeke) in Dar es Salaam Region, Tanzania. Methods We conducted a retrospective study using the secondary data on road accidents from Road Accident Information System (RAIS) for the period 2014 to 2018. Results A total of 6,772 road traffic injuries were reported between 2014 and 2018 and the study recorded the highest RTAs in the year 2014 as compared to the other years within the study period. The death rate from RTAs in Ilala Municipality alone was 36.4 per 100,000 population. About 28% of the total fatalities were recorded among the pedestrians, and there was a significant difference (P < 0.05) in the RTAs among the other road users. Conclusion The study recommends the improvement of road transport infrastructure to ensure safety for all the road users by implementing the existing policies, strengthening the enforcement of existing legislation and introducing express penalties on a real-time basis. We encourage the use of this data to develop strategies in Tanzania that protect pedestrians and other vulnerable road users from RTAs.


Introduction
Road traffic accidents (RTAs) are a major cause of global morbidity and mortality in developing counties [1], resulting in an estimated 20-50 million road traffic injuries (RTIs) and 1.35 million deaths per year [2]. The World Health Organization (WHO) in December 2018 has launched the global status report on road safety and it highlights that the road traffic injuries are now the leading killer of people aged between 5-29 years. Every day, almost 3,700 people are killed globally in road traffic crashes involving cars, buses, motorcycles, bicycles, trucks, or pedestrians. The burden is disproportionately borne by the pedestrians, cyclists and motorcyclists, in particular those living in the developing countries [2]. Overall, 93% of the world's fatalities on the roads occur in low-and middle-income countries, even though these countries have approximately 60% of the world's vehicles than compared with the developed nations. Predictions are that deaths from non-communicable diseases such as RTAs will reach 49.7 million by the year 2020 [2]. Very recent reports show that in low and middleincome countries (LMICs), RTAs are responsible for economic losses of up to 65 billion dollars USD which is more than all development aid income combined [3]. Similarly, the risk of road deaths in these countries is estimated at 32.9 per 100,000 inhabitants as compared to just about 10.3 per 100,000in European countries [4,5] or as compared with the Global road traffic death rate of 17.4 per 100,000 populations [6]. Likewise, in the year 2015, the UN General Assembly established Sustainable Development Goal 3.6 as the target of reducing road traffic deaths and injuries by 50% by 2020 [7]. Because, road traffic injuries are estimated to be the eighth leading cause of death globally for all age groups and the leading cause of death for children and young people. More people now die in road traffic crashes than from the global epidemic HIV/AIDS. Similar to the situation in most developing countries, roads are the dominant mode of transportation whereby 90-95% of the country's goods and passengers are transported by roads. Unfortunately, this extensive use of roads accounts up to 16,211 road fatalities annually [8].
Moreover, the RTAs is associated with a significant economic loss of an estimated 800 USD and 3% of its Gross National Product (GNP) [3].
Of importance, several interventions such as driver training, public awareness campaigns, improvement of roads, increasing fines to RTA offenders, setting speed limits, deploying and regular inspection of vehicles by police have been implemented to address the challenge [5]. According to the global burden of diseases, injuries, and risk factors study (GBD), the road injuries are a unique cause of morbidity and mortality on the global landscape because unlike diseases and injuries for which there may be considerable lag between burden measurement, policy implementation and burden improvement, road injury burden can change rapidly if measures such as seatbelt laws, intoxicated driving laws and infrastructure improvements are implemented [9]. We hypothesized that understanding these trends and patterns can help predict the need for additional services and resources and guide policy-makers on implementing appropriate and sustainable prevention strategies on a long-term basis.

Case definition
The operational case definition for a road traffic accident (RTA) or to 2018. Bartlett model [14] was adapted to establish sample size that was adequate for this study. The road traffic fatality rate was defined as the number of deaths at the scene of RTAs divided by the total number of people involved over the study period. The data was first explored through the use of graphical displays to help identify and analyze trends and patterns in the data and where two or more variables are looked at concurrently; comparative frequencies were used to establish the relationship between them. Descriptive analysis and correlation coefficients were also computed and interpreted. All

Results
The data on road traffic injuries and deaths in Ilala municipality between the year 2014 and 2018 is reflected in Figure 1 Tanzania   Table 2 [12]. Thus, the numbers in the traffic police data would be far much higher. The results from this study agree with that of the other published reports that showed there is a global reduction in death rates from RTAs in Africa region or worldwide [17,18]. Further reports indicate that there are countries which have indeed successfully managed to reduce the number of deaths on roads, although this may not be so in all cases [19,20]. Nevertheless, although the present study showed that RTAs have significantly reduced in the study areas in Tanzania, a very recent report by Kazeem (2019) [21] reveals that death rates from RTAs in Sub-Saharan Africa are still higher than anywhere else in the world. The study investigated the groups of road users mostly affected by RTAs in Ilala as well as Kinondoni and Temeke municipalities in Dar es Salaam. Some indication of the order of priorities in road accident prevention could be gained from the distribution of accident injuries among the various road user classes.

Analysis of relationship between road traffic accidents and the number of registered motor vehicles in
Furthermore, the findings of this study showed that the case-fatality rate for passengers was high in Ilala compared to Kinondoni and Temeke municipalities. Although, the case-fatality rates for drivers, pedestrians, bicyclists and motorcyclists were higher in Kinondoni compared to Ilala and Temeke municipalities where fatality rates were high mostly for passengers. The results showed that 33.57% (2,418) of the total injuries from RTAs occurred to the passengers. This could be attributed to the fact that passengers constitute the majority of vehicle users [22], and public transport is the daily routine for most of  [22,24] which could be the fueling factor for injuries to pedestrians from RTAs. Additionally, there are few pedestrian crossing areas, which should be of particular concern to schools in close proximity to highways [22,25]. Public awareness on road use is fairly low and pedestrians are less likely to use walking pavements even when they are available [22]. Research from Brazil supports this hypothesis that the lack of pedestrian lanes is associated with high-risk features [26]. Likewise, 27.10% (1952) of injuries occurred to motorcyclists. Some reasons which have been put forward concerning this in the Dar es Salaam region in a very recent study include over speeding, reckless driving, traffic violations and driving under the influence of alcohol [27]. Dar es Salaam being a hugely populated region with more than 5 million people has over 300,000 registered motorcycles which are preferred as taxis especially where conventional transportation is uneconomical or physically impossible due to poor road infrastructure [28][29][30]. Studies show that motorcycle injuries are among the leading causes of deaths and the main victims are usually motorists, passengers, and pedestrians [13].
This author reiterates that the risk of dying from a motorcycle accident is 20 times higher than from a motor vehicle. Road users who were least affected by RTAs in all three municipalities were the drivers, bicyclists, and pedal cyclists. In a similar study carried out by Museru et al. (2002) [22], similar findings were reported where just about 7% and 3% of RTAs were attributed to pedestrians and pedal cyclists respectively.

Conclusion
To our knowledge, this is one of the first studies to assess regional level RTAs, fatalities, injuries, incidence and mortality rates in three municipalities of Dar es Salaam Region, Tanzania over a five-year period. This study points out the factors leading to injury severity of RTAs and most at-risk road users in urban Dar es Salaam. In general, prevention strategies in Tanzania have been mainly implemented for vehicle occupant, whereas little attention has been paid to other road users. However, injuries to pedestrians, bicyclists, motor cyclists and pedal cyclists remain a major public health concern. Laws and regulatory frameworks should be formulated and enforced promptly to avoid losses caused by the occurrence of an accident. RTAs require a collaborative approach from different sectors so as to address RTAs in a holistic manner. Pedestrian's walkways and pedal-cyclists lanes should be factored in road design. The government, the police, the health personnel and general public should be incorporated into preventive measures to be formulated. Road safety professionals should be trained, to monitor the magnitude, severity and burden resulting from RTAs in Dar es Salaam to counteract the paucity of evidence occasioned by insufficient data handling skills. According to the GBD on Morbidity and mortality from road injuries, showed clearly that despite improvements in mortality, road injuries remain critically important cause of morbidity and mortality globally, and more research is needed to better measure and understand how road injuries can be prevented, particularly in developing economies.
Investing in preventative measures as well as ensuring that victims of road injuries have access to first response trauma and medical care could help drive improvements in road injury burden in the future [9].
To reduce RTAs and its associated fatalities, the government should improve road infrastructure to facilitate easy movement of all road users, for example by having side-walks to ease movement of pedestrians, and enforce regulations on consistent use of seat belts, avoid over-speeding and overloading of passengers especially in public buses, and conducting regular road safety education campaigns. This study was limited to the three original municipalities of Dar es Salaam and data available in the Road Accident information System at the Regional Traffic Department and could have inconsistent reporting. City planning should therefore incorporate all road users in mind and should focus more on the behavior and the setting. Law enforcement officers should also be trained on different important aspects of road safety. This study also elucidates the RTAs burden and establishes a baseline, which helps to inform future work, with the overall goal of reducing RTAs incidence and mortality in

Tanzania.
What is known about this topic  Road traffic accidents are a major public health concern in Tanzania killing 32.9 per 100,000 people per annum;