Acute Lower Respiratory Tract Infections and Associated Factors Among Under-ve Children Visiting Wolaita Sodo University Teaching and Referral Hospital: A Cross-sectional Study

Background: Lower respiratory tract infections are a leading cause of morbidity and mortality worldwide, particularly in children younger than ve years. Even if the burden of lower respiratory tract infections in children under-ve years had decreased dramatically in the last ten years, it is still the main cause of morbidity and mortality in under ve years old children in developing countries. So, this study was aimed to assess lower respiratory tract infections and associated factors among under-ve children visiting Wolaita Sodo University Teaching and Referral Hospital. Methods: A cross-sectional study was conducted from April 1-30, 2019, among under-ve children attended the Pediatrics outpatient department of Wolaita Sodo University Teaching and Referral Hospital. The data was collected using a semi-structured pre-tested interviewer guided questionnaire. Epi info (version 7.1.2.0) was used for data entry, and Statistical Package for Social Sciences version 20 was used for analysis. Bivariate and multivariate logistic regression, crude and adjusted odds ratio with their 95% condence interval were computed. Finally, p-value <0.05 was used to identify variables that had a signicant association with acute lower respiratory tract infection. Result: The prevalence of acute lower respiratory tract infections among under-ve children was 40.3% (95%CI: 35.7%- 44.9%). Unvaccinated children (AOR: 2, 95% CI, (1.27-3.16)), non-exclusive/replacement feeding (AOR: 1.85, 95% CI, (1.18-2.91)), households mainly used unclean fuel for cooking (AOR: 2.12, 95% CI, (1.07-4.19)), absence of separate kitchen (AOR: 1.7, 95% CI, (1.09-2.65)), and absence of window in the kitchen room (AOR: 1.69, 95% CI, (1.07-2.68)) showed signicant association with acute lower respiratory tract infection. Conclusion: The prevalence of acute lower respiratory tract infections was 40.3%. Unvaccinated children, non-exclusive/replacement feeding, households mainly used unclean fuel for cooking, absence of a separate kitchen, and absence


Introduction
Acute lower respiratory tract infections (ALRTs) are any infections in the lungs or below the voice box, which include pneumonia, bronchitis, and bronchiolitis [1]. So far, pneumonia is the most common type of lower respiratory tract infection (LRTIs), and globally, 150 million new episodes of pneumonia are identi ed per year worldwide, and more than 90% of which occur in developing countries [2,3]. Viruses are the most common cause of pneumonia in infants and young children, and the most frequent symptoms and signs are coughs, increased respiratory rate, fever, breathing di culty, runny nose, and chest wall indrawing in more severe disease [3][4][5][6].
Lower respiratory tract infections (LRTIs) are a leading cause of morbidity and mortality worldwide, particularly in children younger than ve years [7,8]. Globally, LRTIs cause 704 000 deaths, and the highest under-ve LRTI mortalities were in sub-Saharan Africa. Even if the burden of LRTIs in under vechildren has decreased dramatically in the last ten years, it is still the main cause of death in developing countries [8][9][10]. Each year, more than 2 million under ve-children died due to pneumonia in the developing world, and 43% of global under-ve death of ALRTIs occurs in India, Nigeria, the Democratic Republic Congo and Ethiopia [11]. In Ethiopia in 2015, 25,970 under-ve children were dead due to LRTIs, and 14,148.3 was caused by Pneumococcal pneumonia [8].
Different factors were identi ed for the increased risk of LRTIs in children. Of these, poverty, restricted family income, low parental education level, low birth weight, malnutrition, lack of breastfeeding, maternal literacy, smoking, cow dung use for fuel, low socio-demographic status, solid fuels for cooking and heating, immune impaired populations, improved toilet facilities, season, and residence [8,10,12,13]. Similarly, the risk of death from LRTIs will be determined by very severe pneumonia, age below two months, diagnosis of Pneumocystis Carinii, chronic underlying diseases including HIV/ AIDS, severe malnutrition, young maternal age, low maternal education, low socioeconomic status, second-hand smoke exposure, and indoor air pollution [14].
Widespread immunization against in uenza, measles, bacilli Calmette-Guerin (BCG), and now pneumococcus have been related to the decline of the LRTIs in children [3]. Likewise, vaccines prevent an estimated 2.5 million deaths among children under ve every year. Yet one child dies every 20 seconds from a disease that could have been prevented by a vaccine [15]. Ethiopian children suffer four to eight episodes of ARTI on average every year, with the highest occurrence in urban areas in overcrowded living conditions [7]. In Ethiopia, only 39% received all vaccinations at some time, and 22% were vaccinated by the appropriate age [16]. This low immunization coverage will result in an increased risk of LRTIs morbidity and mortality.
Even if Ethiopia has achieved millennium development goals (MDG) 4 by 2013, LRIs are one of the most common causes of under-ve children mortality [17]. Therefore, to achieve the sustainable development goal (SDG) 3 of ending preventable deaths of new-borns and under-ve children by 2030, efforts to reduce deaths due to lower respiratory tract infection should remain a top priority [18,19]. So this study was aimed to assess lower respiratory tract infections and associated factors among under-ve children visiting Wolaita Sodo University Teaching and Referral Hospital (WSUTRH), 2019.

Study design, area and period
An institution-based cross-sectional study was conducted from April 1-30, 2019, at Wolaita Sodo University Teaching and Referral Hospital (WSUTRH). Wolaita Sodo University Teaching and Referral Hospital is found at Sodo town, which is located 157 Km from the regional capital city, Hawassa, and 327 Km from the capital city of Ethiopia, Addis Ababa. According to the Wolaita Zone Health Department information 2019, the estimated population of Wolaita Zone is about 2,020,386 from this, about 983,991 are males, and 1,030,396 are females. The hospital gives service to nearly 3 million peoples in the catchment area, had 350 inpatient beds, and 450-500 patients visited the hospital per-day [20].

Source population
All under ve children/mother or caretaker pair visiting WSUTRH pediatric outpatient department (OPD)

Study population
Randomly selected under ve-children/mother or caretaker pair visited WSUTRH pediatric outpatient department (OPD) from April 1-30, 2019 Sample size determination and procedure The sample size was calculated using a single population proportion formula with the assumption of 50% under-ve prevalence of ALRTIs to get the largest sample size, with a 95% con dence interval and 5% marginal error.
The sample size calculated as follows; Where: n i = initial sample size = con dence interval p = prevalence LRIs W = margin of error By considering a 10% none response rate, the nal sample size was 422 child/mother pairs. The estimated number of child/mother or care taker pair visited under ve OPD in the study period was 1050 based on the last six months of patient ow. Then participants were selected using a systematic random sampling technique (k = 2) until the required sample size was obtained.

Data collection instrument
A face-to-face interview was conducted using a structured questionnaire that was adopted and modi ed from previous researches [21][22][23][24][25][26][27]. The questionnaire comprises socio-demographic factors, maternal and child factors, environmental factors, and the outcome variable (ALRTIs). Length board (< 2 years) or portable stadiometer (≥ 2 years) and portable digital weight scale were used to measure the height and weight of the child, respectively.

Data collection procedure and quality control
The data were collected by four BSc nurses and supervised by two MSc paediatrics and child health nurse professionals. The training was given for data collectors and supervisors for two days, and a pre-test was conducted in 5% (21) of the nal sample size in Sodo Christian hospital. Both supervisors and data collectors were closely followed for the data collection process, and all lled questionnaires were checked every day, and errors were corrected accordingly. The weight of the child was measured using a well-calibrated, portable digital weight scale without shoes and wearing light clothes. Moreover, the reliability of the weight scale was checked before each measurement.

Data entry and analysis
The collected data were checked for completeness, consistency, and accuracy, then entered into EPI data version 3.1 and exported to Statistical Package for Social Sciences version (SPSS) 22.0 for data analysis. Descriptive statistics with percentages, frequency distributions, measures of central tendency, and dispersion were used to describing the data. Bivariate logistic regression was used to check variables having an association with ALRTIs, and those variables found to have a p-value of < 0.2 were further analyzed using multiple logistic regressions. Odds ratio (OR) with 95%CI was computed, and variables with a p-value < 0.05 were considered as a signi cant variable. The model tness was checked with the Hosmer and Lemeshow goodness of t test, which was p = 0.767.

Operational de nitions
Acute lower respiratory tract infections A child presented with cough, fever, rapid or di culty of breathing in the last two weeks and diagnosed as ALRTIs (pneumonia, acute bronchitis, and bronchiolitis) by the physician.

Main cooking fuel:
Unclean fuel using wood, animal dung, charcoal, crop wastes, kerosene stove and kerosene lamp [28] Clean fuel use of electricity, gas, ethanol, and solar [28] Breast feeding: Exclusive breast feeding infants receive only breast milk for the rst six months or receive only breast milk until the time of assessment for infants < six months Non-exclusive/replacement feeding Giving food or uid (milk) alone or in addition to breast milk for the infants < six months Immunization status: Immunized for age Took all vaccines appropriate for age based on the immunization schedule Incomplete defaulters or those who were not vaccinated based on the immunization schedule Not vaccinated a child who didn't take the vaccine at all Result Socio demographic characteristics A total of 414 child/mother or caretaker pairs had participated in the study, which resulted in a 98.1% response rate. The mean age and standard deviation of children and mothers were 21.3±14.13 months and 29±5.8 years, respectively. Nearly half (46.4%) of children were age ≥24 months, the majority (54.6%) of children were male, and 59.4% were urban dwellers. Nearly half of the respondents (49%) were protestant in religion, 32.6% were unable to read and write, and 57.7% were housewives in occupation. Nearly all (93%) children's parents lived together, and the average monthly income of the family was 2356 ± 1316 Ethiopian birr (Table 1).

Environmental factors
Half of the respondents (49.5%) had a family size of ≤4 people, there was a smoker in 6% of the households, and 82.4% of children were cared for by their mothers. The majority of households (67.4%) had a separate kitchen, 71% of cooking areas had windows, and 76.2% of households used unclean fuel for cooking (Table 3).

Factors associated with acute lower respiratory tract infections
In the bivariate analysis, parents living together, history of URTI, vaccination status, breastfeeding in the rst six months, a person who cared for the child, main cooking fuel type, a smoker in the house, a separate kitchen, a window for the kitchen, and nutritional status of the child were factors those had a pvalue <0.2. Variables that had a p-value of < 0.2 in the bivariate analysis were further analyzed using multivariate logistic regression. The result of this analysis showed that immunization status, breastfeeding in the rst six months, main cooking fuel, separate kitchen, and window for the kitchen were signi cantly associated variables with ALRTIs.

Discussion
This study showed that the prevalence of ALRTIs among children who attended at WSUTRH was 40.3% (95%CI: 35.7%-44.9%). The nding of this research is comparable with the demographic and health survey report of Congo (39.8%) and Gabon (38.1%) [12]. However, this nding is higher compared with studies conducted in South West, Ethiopia(28.1%) [22], Wondo Genet district, Ethiopia (33.5%) [21], the overall ALRTIs of sub-Saharan Africa (25.3) [12], the Rio Grande do Sul State, Brazil(23.9%) [29], Rwanda (5%) [13]. The possible reason might be the difference in the study setting and type of lower respiratory tract infection included. This study was conducted in a health facility and includes other ALRTIs in addition to pneumonia. But the above studies were conducted in a community setting or include only pneumonia, which will result in a lower prevalence.
In this study, unvaccinated children were 2 times more likely to be affected by ALRTIs compared with vaccinated for age children. Widespread immunizations have been related to the decline of the LRTIs in children [3,30,31]. Similar ndings were reported from studies in Gamo Gofa Zone, Ethiopia [22], Southern Ethiopia [23], and a systematic review and meta-analysis from the UK [32].
Non-exclusive breast/replacement feed children were 1.85 times more likely to be affected by ALRTIs compared with exclusively breastfeeding children.
Breast milk contains antibodies that help children ght viruses and bacteria. Additionally, children who are breastfed exclusively for the rst six months had a lower risk of acute otitis media, lower respiratory tract infections, gastroenteritis and diarrhea, and asthma [33,34]. Other studies conducted in Northwest Ethiopia [24], Achefer district, Ethiopia [35], Kersa district, Ethiopia [25], Gamo Gofa Zone, South West of Ethiopia [22], Southern Ethiopia [23], a systematic review and meta-analysis from UK [32] showed similar ndings.
Children living in households mainly cooking with unclean fuel had 2.12 times higher odds of developing ALRTIs compared with children living in houses mainly cooked with clean fuel. The use of unclean fuel might produce high levels of household air pollution, including small soot particles that will penetrate deep into the lungs. Deposited particulate matters may alter airway reactivity and will affect the ability of the lungs to ght pathogens. The exposure is high among women and young children, and as a result, it doubles the risk for childhood pneumonia [36][37][38]. Studies conducted in South West of Ethiopia [22], Gondar city of Ethiopia [26], Wolaita-Sodo, Ethiopia [27]and, Pakistan [39] had reported similar ndings.
The absence of a separate kitchen had 1.7 times higher odds of childhood ALRTIs compared with having a separate kitchen. Cooking in the household will result in a higher level of particulate matter concentration, and young children had increased vulnerability to household air pollution due to the longer indoor stay [39]. Similar ndings were observed from the study conducted in Wondo Genet district, Ethiopia [21], South West of Ethiopia [22], and Pakistan [39].
Finally, children who lived in households that had no window in the cooking room (kitchen) were 1.69 times more likely to be affected with ALRTIs compared with those children who lived in houses that had a window in the cooking room. The kitchen without a window had limited ventilation, and it will increase the exposure of pollutants, particularly for young children who spend much of their time in the kitchen with their mother. This nding is supported by studies conducted in Wolaita Sodo, Ethiopia [27], Wondo Genet district, Ethiopia [21], Gondar, Ethiopia [26], and South West of Ethiopia [22].

Limitation Of The Study
This study will be subjected to recall bias, didn't consider seasonal variation, and the diagnosis for ALRTIs was made based on physician assessment.

Conclusion
The prevalence of ALRTIs among under-ve children attended at WSUTRH was 40.3%. Unvaccinated children, non-exclusive/replacement feeding, households mainly cooking with unclean fuel, absence of a separate kitchen, and absence of window in the kitchen room showed signi cant association with ALRTIs. Therefore, strengthening the environmental sanitation (healthy home environment) and family health (child nutrition, immunization) component of the health extension packages will have a signi cant contribution to the reduction of under-ve ALRTIs. Availability of data and materials Data will be available upon request from the corresponding author.