Risk Factors of Pneumonia Among Under-five Children Attending the Public Hospital of Hadiya Central Ethiopia 2024

Abstract

Introduction

Pneumonia is an inflammation of the air sacs in the lungs in response to an injury, such as infection. When the lungs are also involved, it could be referred to as bronchopneumonia. It can be one area of the lung or several areas. According to international data, pneumonia has been the main cause of lower respiratory tract infection (RTI)-related morbidity and mortality. With an anticipated 505,000 deaths worldwide in 2021 (range from 454,000 to 555,000), S. pneumonia was the cause of the greatest percentage of all age-lower RTI-related deaths.

Objective

To identify risk factors of pneumonia among under-five children who visit under-five OPD in Hadiya Zone public hospitals Central Ethiopia 2024.

Method

An institution-based unmatched case-control research design was used in Hadiya zone public hospitals, with 160 cases and 321 controls of children aged 2-59 months included in the sample. The cases were children with pneumonia, while the controls did not have pneumonia. Ethical clearance was obtained. Data was entered using Epi-Data version 4.6 and analyses using SPSS 27 statistical software. Bivariable and multivariable logistic regression analyses were performed to identify determinant factors. Statistical significance was declared at a p-value ≤ 0.05 with adjusted odds ratios (AORs) and 95% confidence intervals (CIs).

Result

Place of cooking (AOR: 2.75, 95%CI: 1.66, 4.58), History of Diarrhea in the past 2 weeks (AOR: 6.37, 95%CI: 3.63, 11.2), History of parental asthma in the family (AOR: 4.32, 95%CI: 2.31, 8.05), and a children received PCV vaccine during their infancy period (AOR: 2.09 95%CI: 1.24, 3.51), were found to be risk factors of under-five pneumonia.

Conclusion

In this study, the risk of pneumonia among under-five children was significantly associated with several factors, including whether the children came from households where people cooked indoors, whether the children had experienced diarrhea in the past two weeks, whether the children came from families where parents experienced asthma, and whether the children received the PCV vaccine in infancy. These factors are of critical importance in the management of pneumonia among under-five children and therefore warrant interventions aimed at reducing the risk of pneumonia in this group of people.

Keywords

pneumonia child risk factors under-five children and public hospitals Ethiopia

Introduction

Pneumonia is an inflammation of the air sacs in the lungs in response to an injury, such as infection. When the airways are also involved, it may be called bronchopneumonia (Ambroggio et al., 2023). According to international data, pneumonia has been the main cause of lower respiratory tract infection (RTI)-related morbidity and mortality. With an anticipated 505,000 deaths worldwide in 2021 (range from 454,000 to 555,000), S. pneumonia was the cause of the greatest percentage of all age-lower RTI-related deaths (1. GBD 2021 LRI Collaborators, 2024).

Yet over 5 million children are dying every year, and pneumonia accounts for nearly 20% of the deaths. The rate of progress in reducing pneumonia-related mortality has been slower than for other leading causes of child deaths (United Nations Inter-agency Group for Child Mortality Estimation, 2024c).

The World Health Organization data indicates that pneumonia resulted in the deaths of 147,180 children under-five years old, accounting for 22% of all fatalities among children aged 1 to 5 years. The incidence rate of under-five pneumonia is 0.29 episodes per child-year. The developing country accounts for 151.8 million cases per year; of these, 74% are accounted for by fifteen world countries, including Ethiopia (UNICEF, 2021). On the other hand, Southeast Asia and Africa are the two continents with the highest rates of under-five pneumonia, reporting an estimated 61 million and 35 million childhood pneumonia cases annually, respectively and also out of all the continents, Africa has the most significant incidence and severe cases of pneumonia (Abebaw et al., 2022).

Different reports show that from sub-Saharan Africa, Ethiopia has the highest rate of pneumonia, with an estimated 3.37milloin children affected by pneumonia annually, Ethiopia consistently ranks among the top nations in the world for under-five pneumonia mortality, usually ranking fifth or sixth among the top 15 countries with the highest burdens, according to current statistics and studies going up to 2023–2024. (18%-20% deaths (Girma et al., 2023).

Based on UNICEF reports, pneumonia accounts for 16% of all under-five deaths in sub-Saharan Africa compared to 14% for malaria and 10% for acute diarrheal diseases (UNICEF, 2023). In Ethiopia, as well as Hadiya Zone, pneumonia is a significant public health issue. However, there is a lack of local knowledge on specific risk factors for the development of pneumonia. The purpose of this study is to generate knowledge on specific risk factors for pneumonia among children aged less than five years in Hadiya Zone public hospital.

Review of Literature

Pneumonia is the leading cause of mortality and morbidity in children; according to the World Health Organization, pneumonia accounts for around 14% of deaths in children under five years old. Half of these deaths occur in sub-Saharan Africa (World health organization [WHO] 2023).

Ethiopia is among the countries with a high burden of under-five mortality, where pneumonia is a significant contributor. According to the Ethiopian demographic health survey report, acute respiratory infections, especially pneumonia, are the most common childhood illnesses (Ethiopian Statistical Service. (2026)).

Sociodemographic Related Factors

Several studies have identified multiple determinants of pneumonia among under-five children. A case-control study conducted in the Bangladesh stated that maternal age and the academic status of the mother and preterm babies were significantly associated with pneumonia (Islam et al., 2024). Another case-control study done in northeast Ethiopia confirmed that children having older mothers and having mothers who are housewives by occupation significantly play a role in the development of pneumonia (Bazie et al., 2021).

Maternal and Child-Related Factors

Maternal and child-related factors also play a crucial role in developing pneumonia. An Indonesian case-control study found that non-exclusive breastfeeding, lack of vaccination, and malnutrition increased the risk of under-five pneumonia (Sutriana et al., 2021). A study conducted in the tertiary hospital of Mogadishu, Somalia, shows that unvaccinated children, allergic disease in the family, and children’s history of pneumonia for the past two weeks were factors that affected under-five pneumonia (Roble et al., 2025).

On the other hand a hospital-based study in South Africa reported that HIV-exposed and malnourished children had a higher risk of under-five pneumonia (Le Roux et al., 2021). A study in Eastern Ethiopia found that malnutrition, lack of vaccination, altered mental status, complicated pneumonia, and cigarette smoke exposure increased the risk of pneumonia in children (Adbela et al., 2024). Similarly, a case-control study in Jijiga found that incomplete vaccination, cooking smoke exposure, household respiratory infections, diarrhea, and female sex increased the risk of under-five pneumonia (Osman et al., 2025).

Household and Environmental

Environmental factors are among the most important determinants of childhood pneumonia.

A study conducted in Bangladesh by found that poor household environmental conditions, including overcrowding, indoor smoke exposure, and the use of unclean cooking fuels, were significantly associated with respiratory infections among under-five children (Islam et al., 2024). A study conducted in Gamo Zone, southern Ethiopia, reported that children from households where food was cooked inside the living room had a significantly higher risk of pneumonia (Solomon et al., 2022).

Methods and Materials

Study Area and Period

The study was conducted in Hadiya zone, which is the capital city of the Central Ethiopia region; also, it is one of the 7 zones in Central Ethiopia. It has 13 woredas and 4 town administrations with a total of 329 kebeles, of which 303 are rural and 26 are urban. It is located 230 Km away from the capital city of Ethiopia. It is situated at an altitude of 1800-2950 meters above sea level and has an average temperature ranging from 10 to 24 degrees centigrade. The zone has 1 specialized hospital and 3 first-level hospitals. This study was conducted in public hospitals of the Hadiya zone from February 1 to March 30, 2024.

Study Design

Institutional based un-matched case-control study design was conducted to asses’ Risk Factors of pneumonia.

Source Population

All under-Five Children who visit the Hadiya Zone Public Hospital’s Pediatrics OPD.

Study Population

All selected under-five children who visited the selected Hadiza zone Public Hospital’s pediatrics OPD during the study period.

Sample Population

All under-five children who fulfill the inclusion criteria at the selected public hospitals were included in the study.

Case Definition

All under-five children with a diagnosis of pneumonia who come for treatment service during the data collection period.

Definition of Pneumonia Diagnosis

Clinical and radiographic criteria were used in this investigation to diagnose pneumonia. Clinically, the diagnosis was made in accordance with the criteria of the Integrated Management of Neonatal and Childhood Illness (IMNCI), which was defined as the presence of cough and/or breathing difficulties along with age-specific fast breathing and/or chest indrawing. Chest X-ray results consistent with pneumonia, such as the presence of lung infiltrates, consolidation, or other suggestive abnormalities, as reported in patient records, served as the basis for radiological confirmation.

Control Definition

All under-five children who visited a ‘sick-baby clinic’ and were registered and classified for a condition other than pneumonia within a similar study period.

Control Selection

Controls were under-five children attending the same OPD during the same period as cases but without pneumonia based on IMNCI assessment. Cases and controls were selected from the same health facilities and catchment population, improving comparability, reducing selection bias, and enhancing internal validity.

Inclusion Criteria

All under-five children who visited the selected public hospital during the study period were eligible for inclusion.

Exclusion Criteria

• Caregivers who did not have information about the child at the time of data collection were excluded.

• Children with cough due to a recent history of liquid or foreign body aspiration were excluded.

• Infants aged less than two months were excluded.

• Severe pneumonia cases were excluded.

To establish a fairly homogeneous study sample and to concentrate on pneumonia Risk Factors among outpatient and early emergency presentations, children with severe pneumonia necessitating hospitalization were excluded. In addition to producing findings relevant to basic healthcare and community-level initiatives, this strategy reduces confounding from illness severity and concomitant diseases, which are more prevalent among hospitalized patients.

Sample Size Determination and Sampling Procedure

The sample size was determined using the double population proportion exposure difference formula by considering major determinant variables such as: number of families, birth to 6 months feeding practices, and the main house without a window. Considering the number of families with more than four was selected as an independent predictor, since it yielded the maximum sample size as compared to other exposure variables, which reduces the role of chance findings. The sample size was determined using Open Epi version 7.2.0.1. The following assumptions were put into consideration: Confidence level of 95%, power of the study 80%, the case-control ratio 1:2, and expected percent of exposures in control and expected percent of exposure among cases taken from different studies (Table 1).

Table 1.

Sample Size Determination for Risk Factors of Pneumonia Among Children Under-five Years in a Hospital-Based Case-Control Study in Public Hospitals in Hadiya Zone, Central Ethiopia, 2024

No	Variables	AOR	% of controls exposed	Total samplesize (cases +controls)	Ref.
1	Poor hand washing practice	3.11	32	146+291=437	(Kifle et al., 2023)
2	URTI history in child	5.46	20	120+240=360	(Kifle et al., 2023)
3	Mainly, a house without windows	2.42	42.43	84+101=185	(Getahun et al., 2022)

Finally, the maximum sample size is 437 (146 cases and 291 controls) after adding a 10% non-respondent rate. 44+437=481(160 cases and 321 controls) was taken for the study.

Sampling Procedure

Among the four public hospitals found in the Hadiya zone, two were selected using simply random sampling. The estimated number of outpatient visits to the under-five children outpatient department of each hospital for two months was counted from registrations and used as a baseline. Then the sample size for each hospital was proportionally allocated. The total sample size was then proportionally allocated to each selected hospital. Systematic random sampling was used to select both cases and controls. The estimated two-month study populations were 240 cases and 710 controls from Nigist Eleni Mohammed Memorial Comprehensive Specialized Hospital (NEMMCSH), and 86 cases and 264 controls from Shone Hospital.

The sampling interval (k) was calculated for each hospital separately. For NEMMCSH, k was approximately 3 for controls (710/234 ≈ 3) and 2 for cases (240/117 ≈ 2), meaning every 3rd control and every 2nd case was selected. Similarly, for Shone Hospital, k was approximately 3 for controls (264/87 ≈ 3) and 2 for cases (86/43 ≈ 2), meaning every 3rd control and every 2nd case was selected (Figure 1).

Figure 1.

Schematic presentation of the sampling procedures used to select study participants in public hospitals in Hadiya zone, Central Ethiopia, 2024

The sampling frame included all children less than five years of age who attended the outpatient department of the health facilities involved in the study during that period. All eligible participants were identified from outpatient registration records, which were considered comprehensive.

Data Collection Instrument and Procedures

Parents of children aged two months to five years who were present during data collection were eligible to participate in the study. Face-to-face interviews and document reviews were conducted to collect data on socio-demographic and other independent variables. Before data collection, the questionnaire was pretested to ensure clarity, consistency, and contextual relevance. Findings from the pretest were used to make necessary modifications to improve comprehension and relevance.

The final questionnaire demonstrated acceptable internal consistency (Cronbach’s alpha = 0.82). It was adapted from previously validated tools and relevant literature (Bazie et al., 2021; Getahun et al., 2022; Kifle et al., 2023,). Participants were classified as cases and controls by physicians based on clinical examination and chest X-ray findings. Data collection was conducted individually in a convenient setting for respondents, and all information was recorded using a structured data collection sheet developed for the study.

Data Quality Control

The questionnaire was evaluated by experts in related fields. Intensive training that lasts two days was offered by the principal investigator to the data collectors and supervisors on the technique of timely data collection, the purpose of data collection, and the contents of the questionnaires. The data collection instrument was pretested on 5% of the total sample size. The principal investigator and field supervisor closely monitored trained data collectors to ensure that the study protocol was followed and the responses were completed. The completed questionnaires were checked daily for consistency and completeness. In data entry, double verification was used, and any differences were resolved by cross-checking the data. All data were further reviewed by the supervisor and principal investigator for completeness and consistency.

Data Processing and Analysis

Data was entered using Epi-Data version 4.6 and analyzed using SPSS 27 statistical software. Model adequacy was assessed using the Hosmer–Lemeshow goodness-of-fit test. A bivariate logistic regression analysis was performed for each independent variable. Accordingly, those variables having a p-value less than or equal to 0.05 in the bivariate analysis were fitted to the multivariable logistic regression model. In multivariable regression, a P-value less than or equal to 0.05 was considered statistically significant. Multi-collinearity among independent variables was checked by the variance inflation factor (VIF).

Results

Sociodemographic Characteristics of the Respondents

The study included all mothers with their children who provided consent, resulting in a response rate of 100%.Of this, 73 (45.6%) of cases and 143 (44.5%) of controls were permanently rural residences. The mothers who participated in the study had an average age of 28.69 (SD ±4.94) for cases and 27.96 (SD ±5.87) for control. In contrast, the mean age of children in the study was 26.73 (SD ±17.43) months for cases and 19.9 (SD ±14.22) months for control (Table 2).

Table 2.

Sociodemographic Characteristics of the Participants in Public Hospitals in Hadiya Zone, Central Ethiopia, 2024

Variable (N=481)	Category	Case (N=160)		Control (N=321)
Variable (N=481)	Category	Frequency	Percent	Frequency	Percent
Age of the mother	18-26	19	11.9	109	34.0
	27-35	94	58.8	145	45.2
	>=36	47	29.4	67	20.9
Educational status of the mother	No formal education	29	18.1	70	21.8
	Primary	60	37.5	124	38.6
	Secondary	41	25.6	88	27.4
	Higher education	30	18.8	39	12.1
Residence	Rural	73	45.6	143	44.5
Residence	Urban	87	54.4	178	55.5
Educational status of father	No formal education	17	10.6	76	23.7
	Primary	54	33.8	103	32.1
	Secondary	39	24.4	80	24.9
	Higher education	50	31.3	62	19.3
Occupation status of mother	House wife	112	70	137	42.7
	farmer	13	8.1	107	33.3
	Government	25	15.6	49	15.3
	Merchant	10	6.3	28	8.7
Occupation status of father	Farmer	67	41.9	123	38.3
	Government	50	31.3	112	34.9
	Merchant	43	26.9	86	28.8
Age of the child	2monthe – 11month	16	10	92	28.7
	12month – 27month	77	48.1	145	45.2
	28 months – 59 months	67	41.9	84	26.2
Sex of the child	Male	72	45	166	51.7
Sex of the child	Female	88	55	155	48.3
Family size	More than four	92	57.5	136	42.4
Family size	Less than or equal to 4	68	42.5	185	57.6

Household and Environmental Characteristics of the Participants

About 44 (27.5%) of the case population and 177 (55.1%) of the control population used charcoal/wood for cooking. More than fifty percent (91, 56.9%) of the cases and 151 (47%) of the control children had a family history of cigarette smoking. Nearly equal proportions of the cases, 45% and 46.1% of control participants, lived in a house without a window (Table 3).

Table 3.

Household and Environmental Characteristics of the Respondents in Public Hospitals in Hadiya Zone, Central Ethiopia, 2024

Variable (N=481)	Category	Case (N=160)		Control (N=321)
Variable (N=481)	Category	Frequency	Percent	Frequency	Percent
Proper hand washing practice	Yes	79	49.4	171	53.3
Proper hand washing practice	No	81	50.6	150	46.7
Fuel used for cooking	Charcoal/wood	44	27.5	177	55.1
	Gas	55	34.4	89	27.7
	Electricity	61	38.1	55	17.1
A family history of cigarette smoking	Yes	91	56.9	151	47
A family history of cigarette smoking	No	69	43.1	170	53
Presence of a window	Yes	88	55	173	53.9
In the house	No	72	45	148	46.1
Mother/caregiver carrying child on her back while cooking	Yes	77	48.1	148	46.1
Mother/caregiver carrying child on her back while cooking	No	83	51.9	173	53.9
Place of cooking	In kitchen	120	75	162	50.5
Place of cooking	In house	40	25	159	49.5
Separate Cattle room	Yes	94	58.8	171	53.3
Separate Cattle room	No	66	41.3	150	46.7

Parental and Child-Related Characteristics

Of all under-five children included in the study, 20 (12.5%) of cases and 154 (48%) of controls had a history of diarrhea in the last two weeks. More than half of the cases, 81 (50.6%), and control 175 (54.5%) of children received their pentavalent vaccine. Similarly, 122 (76.3%) of cases and 180 (56.1%) of controls received the PCV vaccine (Table 4, Figure 2).

Table 4.

Parental and Children-Related Characteristics of Respondents in Public Hospitals in Hadiya Zone, Central Ethiopia

Variable (N=481)	Category	Case (N=160)		Control (N=321)
Variable (N=481)	Category	Frequency	Percent	Frequency	Percent
Diarrhea in the last 2 weeks	Yes	20	12.5	154	48
Diarrhea in the last 2 weeks	No	140	87.5	167	52
URTI in the last 2 weeks	Yes	81	50.6	155	48.3
URTI in the last 2 weeks	No	79	49.4	166	51.7
History of parental asthma in the family	Yes	21	13.1	135	42.1
History of parental asthma in the family	No	139	86.9	186	57.9
A child received the Pentavalent vaccine	Yes	81	50.6	175	54.5
A child received the Pentavalent vaccine	No	79	49.4	146	45.5
A child received the PCV vaccine	Yes	122	76.3	180	56.1
A child received the PCV vaccine	No	38	23.7	141	43.9
A child received the measles vaccine	Yes	74	46.3	146	45.5
A child received the measles vaccine	No	86	53.7	175	54.5
Child HIV status	Negative	153	95.6	314	97.8
Child HIV status	Positive	7	4.4	7	2.2
The weight for height of a child	Wasted (≤ -2 SD)	29	18.1	82	25.5
The weight for height of a child	Normal ( ≥ -2 SD)	131	81.9	239	74.5
The weight for age of the child	Underweight (≤ -2 SD)	26	16.3	98	30.5
The weight for age of the child	Normal ( ≥ -2 SD)	134	83.7	223	69.5
A child having repeated attacks of pneumonia	Yes	52	32.5	100	31.2
A child having repeated attacks of pneumonia	No	108	67.5	221	68.8
Birth to 6 Months Breastfeeding Practice	Non exclusive	63	39.4	129	40.2
Birth to 6 Months Breastfeeding Practice	Exclusive	97	60.6	192	59.8

Figure 2.

Distribution of PCV vaccination status among children under five years in public hospitals in Hadiya Zone, Central Ethiopia

Diagnostic Frequency Distribution of Control Group

Several conditions other than pneumonia were found in the controls. The most frequent diagnoses were feverish illnesses, severe diarrheal disorders, upper respiratory tract infections, and other minor ailments. IMNCI clinical evaluation and, when available, chest X-ray results were used to determine the control group (Supplementary table-1).

Risk Factors of Under-five Pneumonia

Binary logistic regression analysis was utilized to uncover independent factors of pneumonia in children under the age of five. First, the respondents’ socio-demographic variables, housing, and environmental variables, as well as parent- and child-related characteristics, were compared to the outcome variable, which was a risk factor, using a bivariate analysis. Variables with a p-value ≤ 0.05 were entered into the final multivariable logistic regression model.

In the multivariable analysis, adjusted odds ratios (AORs) with a p-value ≤ 0.05 were considered statistically significant, variables with AOR >1 was considered to increase the odds of pneumonia, while those with AOR <1 was considered protective. The logistic regression model showed an adequate fit according to the Hosmer–Lemeshow test (χ² = 6.189, p = 0.626), indicating that the predicted probabilities were consistent with the observed outcomes. As a result, place of cooking, history of diarrhea in the past 2 weeks, history of parental asthma in the family, and children receiving the PCV vaccine during their infancy period were significantly associated with under-five-year-old pneumonia. (Table 5).

Table 5.

Bivariable and Multivariable Logistic Regression Analysis of Factors Associated With Pneumonia Among Children Under-five-Years in Public Hospitals of the Hadiya Zone, Central Ethiopia, 2024 (N = 481)

Variable (N=481)	Category	Under-five pneumonia		COR (95%CI)	AOR (95%CI)	P-value
Variable (N=481)	Category	Case (n=160) n (%)	Control (n=321) n (%)	COR (95%CI)	AOR (95%CI)	P-value
Residence	Rural	73(45.6%)	143(44.5%)	1.96(1.48,2.9)	0.88(0.57,1.37)	0.56
Residence	Urban	87(54.4%)	178((55.5%)	1	1	0.56
Sex of the child	Female	88((55%)	166(51.7%)	1.76(1.35,2.9)	0.86(0.46,1.02)	0.67
Sex of the child	Male	72(45%)	155(48.3%)	1	1	0.67
Presence of window	Yes	88(55%)	173((53.9%)	1	1	0.089
Presence of window	No	72(45%)	148(46.1%)	2.05(1.55,2.72)	0.65(0.4,1.06)	0.089
Place of cooking	In kitchen	120(75%)	162(50.5%)	1	1	0.001
Place of cooking	In house	40(25%)	159(49.5%)	3.1(2.81,5.62)	2.75(1.66,4.58)	0.001
Diarrhea in the last 2 weeks	Yes	20(12.5%)	154(48%)	6.5(4.83,12.26)	6.37(3.63,11.2)	0.001
Diarrhea in the last 2 weeks	No	140(87.5%)	167(52%)	1	1	0.001
URTI in the last 2 weeks	Yes	81(50.6%)	155(48.3%)	1.91(1.46,2.5)	0.82(0.53,1.28)	0.39
URTI in the last 2 weeks	No	79(49.4%)	166(51.7%)	1	1	0.39
parental asthma History	Yes	21(13.1%)	135(42%)	5(4.01,10.2)	4.32(2.31,8.05)	0.001
parental asthma History	No	139(86.9%)	18658%)	1	1	0.001
A child received the PCV vaccine	Yes	122(76.2%)	180(56.1%)	1	1	0.005
A child received the PCV vaccine	No	38(23.8%)	141(43.9%)	3.71(2.6,5.3)	2.09(1.24,3.51)	0.005
The weight for height of a child	Wasted (≤ -2 SD)	29(18.1%)	82(25.5%)	2.0(1.85,4.31)	0.55(0.29,1.04)	0.06
The weight for height of a child	Normal ( ≥ -2 SD)	131 (81.9%)	239(74.5%)	1	1	0.06
A child having repeated attacks of pneumonia	Yes	52(32.5%)	100(31.2%)	1.62(1.37,2.68)	0.61(0.36,1.02)	0.061
A child having repeated attacks of pneumonia	No	108(67.5%)	221(68.8%)	1	1	0.061
Breastfeeding Practice	Non exclusive	63(39.4%)	129(40.2%)	2.04(1.51,2.76)	0.82(0.5,1.33)	0.42
Breastfeeding Practice	Exclusive	97(60.6%)	192(59.8%)	1	1	0.42

Note. COR = crude odds ratio; AOR = adjusted odds ratio; CI = confidence interval; PCV = pneumococcal conjugate vaccine; URTI = upper respiratory tract infection.

Odds ratios are from binary logistic regression. The reference category for each variable is indicated as “1 (Reference)”. Odds ratios represent the odds of pneumonia relative to the reference group. All estimates were obtained from logistic regression models.

Discussion

Pneumonia in children under the age of five is a prominent cause of illness and death globally, with particularly high rates in impoverished countries such as Ethiopia. Understanding the determining variables is critical for developing an effective care and preventive approach for pediatric pneumonia. These studies identify easy-to-prevent determining variables. The findings of this study showed that place of cooking, history of diarrhea in the preceding two weeks, parental history of asthma, and pneumococcal conjugate vaccine (PCV) status during infancy were significantly associated with pneumonia among under-five children.

Findings should be interpreted as associations rather than causal relationships due to the observational nature of the study. In addition, the results should be interpreted with caution because of potential selection and information biases inherent in the hospital-based case–control design.

The place of cooking was the key variable that indicated association with under-five pneumonia. Children from households where cooking was conducted inside the living house had significantly higher odds of developing pneumonia compared to those with a separate kitchen (AOR = 2.75, 95% CI: 1.66–4.58).

Similar studies in Indonesia; Gamo Zone southern,Ethiopia; and a study conducted in Worabe, Ethiopia, respectively, support this result (Abate et al., 2021; Seramo et al., 2022; Solomon et al., 2022; Sutriana et al., 2021).

This could be due to indoor pollution from unsafe energy sources such as charcoal, wood, and biomass. Indoor air pollution, notably from the use of solid fuels for cooking and heating, is a major risk factor for childhood pneumonia, particularly in nations with low and moderate income levels like Ethiopia. Exposure to these pollutants weakens a child’s respiratory system, leaving them more susceptible to diseases like pneumonia. Reducing indoor air pollution through initiatives like encouraging clean fuel usage and better cooking stoves is critical for pneumonia prevention.

Children with a history of diarrhea in the last two weeks had markedly higher odds of pneumonia compared to those without such history (AOR = 6.37, 95% CI: 3.63–11.2). This study was consistent with other previous studies in Spain, Uganda, Gambela, Ethiopia and Gonder, Ethiopia, respectively (Bazie et al., 2021; Prat, C et al., 2021; Getahun et al., 2022; Wanyana et al., 2024).

The possible reason may be due to the fact that the history of diarrhea is strongly associated with the development of pneumonia in children under five, and diarrhea is one of the main causes of mortality in this age range. This elevated risk is probably brought on by a compromised immune system as well as other elements associated with inadequate sanitation and hygiene. Consequently, in order to lessen the burden of these infectious diseases, important preventative strategies include the rotavirus vaccine, hand washing with soap, access to safe drinking water, better sanitation, and exclusive breastfeeding for the first six months.

Similarly, children with a family history of parental asthma had increased odds of pneumonia compared to those without such history (AOR = 4.32, 95% CI: 2.31–8.05). This finding agreed with studies conducted in different parts of the world: Malaysia, the Netherlands, and Worabe, Ethiopia, respectively (Ramzi, N., et al., 2024; Seramo et al., 2022).

The possible explanation might be that an important risk factor for pediatric pneumonia is a history of parental asthma; evidence suggests that children who have asthmatic parents are at a higher risk of contracting pneumonia themselves. Common genetic predispositions and environmental variables that promote vulnerability to both illnesses are probably the cause of this connection. Genetic factors can impact both pneumonia and asthma. A child who has an asthmatic parent may inherit genes that increase their vulnerability to respiratory conditions like pneumonia. Children who suffer from asthma or pneumonia are more susceptible to respiratory infections since these conditions can impact immune system development and function.

The PCV vaccine was also another factor identified to affect the occurrence of pneumonia in children under five years old. Children who did not receive the pneumococcal conjugate vaccine (PCV) had higher odds of developing pneumonia compared to vaccinated children (AOR = 2.09, 95% CI: 1.24–3.51). Those similar studies done in different countries, like the Public Health Foundation of India, state systematic reviews in East Africa and at Jimma University Medical Center in Ethiopia, respectively (Abate et al., 2021; Singh et al., 2022; Tegenu et al., 2022) support the finding.

This association might be immunization mitigates childhood pneumonia through two mechanisms. Firstly, vaccinations avert infections that directly induce pneumonia, such as Haemophilus influenza type B, and infections like measles and pertussis that can indicate pneumonia as a complication can also be avoided by vaccination. On the other hand, PCV functions via boosting the immunological system to generate antibodies against the Streptococcus pneumonia bacterium, a prevalent cause of pneumonia.

PCV has demonstrated considerable efficacy in decreasing the occurrence of pneumococcal pneumonia in children, with research indicating substantial decreases. The vaccination further safeguards against other serious pneumococcal infections such as meningitis and sepsis, which can be life-threatening in hospitalized patients and in situations of radiologically, confirmed pneumonia. PCV has significantly reduced pneumonia-related fatalities in children by preventing pneumococcal pneumonia.

Lastly, the results of this study have significant ramifications for public health management, especially in environments with limited resources where pneumonia remains a major cause of illness and mortality in children under five years. By identifying significant factors, this study presents practical evidence for focused intervention. Increasing community-based child health programs includes increasing immunization coverage, lowering exposure to indoor air pollution, preventing exposure to diarrheal disease, and early identification of family history of asthma. Cold reduced the burden of under-five pneumonia.

Strengths and Limitations of the Study

Data were collected from multiple public hospitals in Hadiya Zone, improving the variability of participants and enhancing internal validity. A relatively large sample size with an adequate case-to-control ratio was used, increasing the statistical power of the study. Pneumonia cases were ascertained using standard clinical criteria.

This study has several limitations. First, selection bias in the control group cannot be fully ruled out, which may affect the comparability between cases and controls. In addition, recall bias may have influenced some exposure variables, including indoor cooking practices and parental history of asthma. Although data were collected prospectively, the case–control design inherently limits the ability to establish causal relationships.

Implications for Practice

The results of this study suggest targeted interventions to control and prevent pneumonia in young children in such settings. Strengthening routine immunizations, improving indoor air quality, and promoting early health-seeking behaviors among caregivers are important. It is important for healthcare workers to emphasize early screening of high-risk young children and community-based health education for caregivers to avoid preventable risk factors.

Conclusion and Recommendations

These factors are of critical importance in the management of pneumonia among under-five children and therefore warrant interventions aimed at reducing the risk of pneumonia in this group of people. So to decrease the risk of pneumonia, caregivers need to enhance ventilation, address diarrhea, and vaccinate at the appropriate time against PCV, while health workers need to educate families and identify at-risk children, and policymakers need to advocate for clean cooking, strengthen immunization, and raise awareness about the risk of pneumonia in families.

Supplemental Material

Supplemental Material - Risk Factors of Pneumonia Among Under-five Children Attending the Public Hospital of Hadiya Central Ethiopia 2024

Supplemental Material for Risk Factors of Pneumonia Among Under-five Children Attending the Public Hospital of Hadiya Central Ethiopia 2024 by Seifu Awgchew Mamo, Sisay Foga, Rediet Gebreselassie Kelelew, Eliase Ezo, and Asnakech Zekiwos Heliso in Sage Open Nursing.

Footnotes

Acknowledgment

We would like to thank the study participants for the scarification of their valuable time spent filling out questionnaires, selected Hadiya Zone Public Hospitals, and Wachemo university.

ORCID iDs

Seifu Awgchew Mamo

Eliase Ezo

Asnakech Zekiwos Heliso

Ethical Considerations

Ethical clearance was obtained from Wachemo University College of medicine and health science, institutional review board (WCU/IRB/0039/24) and a formal letter of cooperation to conduct this research was written to select Hadiya Zone Public Hospitals.

Consent to Participate

Each participant provided written informed consent, and the data collected from them would not have been shared. To maintain secrecy, privacy, and anonymity, names and other personally identifiable information about respondents were removed using coding. The participants were made fully aware that they might revoke their permission at any moment without incurring any fees or losing any advantages.

Author Contributions

Seifu Awgchew and Sisay Foga: Conceptualization, Data curation, Formal analysis, Investigation, Methodology, Supervision, Validation, Visualization, Writing-original draft, Writing-review & editing. Seifu Awgchew and Asnakech Zekiwos: Conceptualization, Data curation, Formal analysis, Investigation, Methodology, Supervision, Validation, Visualization, Writing-original draft, Writing-review & editing. Elias Ezo and Rediet Gebreselassie: Conceptualization, Formal analysis, Methodology, Software, Writing-review & editing. Rediet Gebreselassie:, Seifu Awgchew and Asnakech Zekiwos: Conceptualization, Formal analysis, Methodology, Software, Writing-review & editing. Sisay Foga and Asnakech Zekiwos: Conceptualization, Formal analysis, Methodology, Software, Writing-review & editing, Rediet Gebreselassie: and Seifu Awgchew Conceptualization, Formal analysis, Methodology, Supervision, Visualization, Writing-original draft, Writing-review & editing. Elias Ezo, Seifu Awgchew, Rediet Gebreselassie: and Asnakech Zekiwos: Conceptualization, Formal analysis, Methodology, Software, Writing-review & editing.

Funding

The authors received no financial support for the research, authorship, and/or publication of this article.

Declaration of Conflicting Interests

The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Supplemental Material

Supplemental material for this article is available online.

Appendix

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