Acute respiratory tract infections (ARTIs) continue to be a major global public health concern and are among the most prevalent illnesses affecting children under five. A significant percentage of paediatric outpatient visits, hospital admissions, and childhood death are caused by these infections, especially in underdeveloped nations. Because of their high frequency, recurrent nature, and related problems, respiratory infections continue to be a major burden despite tremendous advancements in healthcare [1, 2]. A wide range of conditions affecting the upper and lower respiratory tracts are referred to as acute respiratory tract infections. The common cold, pharyngitis, tonsillitis, sinusitis, and otitis media are examples of upper respiratory tract infections (URTIs), while bronchiolitis, bronchitis, and pneumonia are examples of lower respiratory tract infections (LRTIs). LRTIs are linked to higher morbidity and mortality and frequently necessitate hospitalisation and intense medical care, whereas the majority of URTIs resolve on their own [3-5]. Due to their underdeveloped immune systems, narrower airways, malnutrition, and increased exposure to infectious agents, children under five are more susceptible to respiratory infections. The risk of respiratory tract infections is further increased by a number of environmental and socioeconomic variables, including overcrowding, substandard housing, indoor air pollution, parental smoking, non-exclusive breastfeeding, insufficient immunisation, and malnutrition [6, 7]. Depending on the location and intensity of infection, ARTIs can present with a variety of clinical symptoms. Fever, cough, nasal discharge, sore throat, wheezing, breathing difficulties, chest retractions, and poor feeding are typical symptoms. The severity might vary from a little sickness that resolves on its own to severe pneumonia that necessitates hospitalisation and supportive care. For the purpose of directing treatment choices and minimising needless antibiotic use, accurate clinical evaluation and suitable classification of respiratory infections are crucial [8, 9]. It has been demonstrated that a number of preventive strategies can lessen the prevalence of respiratory tract infections in young children. Complete immunisation, exclusive breastfeeding throughout infancy, sufficient nutrition, better sanitation, lowering indoor air pollution, and avoiding tobacco smoke exposure, and early healthcare seeking are some of these. Reducing the frequency and severity of respiratory infections is largely dependent on public health initiatives that address these modifiable risk factors [10, 11]. Understanding the frequency, clinical presentation, and risk factors of respiratory tract infections in certain populations is crucial due to the high burden of these illnesses among young children and their effects on child health. In order to ascertain the frequency and clinical range of acute respiratory tract infections among children under five who are enrolled in a tertiary care facility, as well as to identify common environmental and demographic factors linked to these illnesses, the current study was conducted [12, 13].

This prospective observational study was conducted in the Department of Paediatrics, Kanya Kumari Medical Missions Medical College, Kanyakumari, Tamil Nadu, between August 2024 and July 2025. A total of 30 children under five years of age presenting with symptoms suggestive of acute respiratory tract infections (ARTIs) were included in the study after obtaining informed consent from their parents or legal guardians. Ethical approval for the study was obtained from the Institutional Ethics Committee prior to commencement. All enrolled children underwent detailed clinical evaluation including history taking, physical examination, nutritional assessment, immunization status evaluation, and relevant laboratory and radiological investigations whenever indicated. Methods: The patient's age, gender, socioeconomic status, nutritional status, history of vaccinations, nursing habits, family history, exposure to smoking in the home, overcrowding, presenting symptoms, clinical findings, course of treatment, and results were all noted. Patients were divided into lower respiratory tract infections (LRTIs), such as pneumonia, bronchiolitis, and bronchitis, and upper respiratory tract infections (URTIs), and such as the common cold, pharyngitis, tonsillitis, otitis media, and sinusitis, based on clinical evaluation and pertinent investigations. Clinical manifestations were recorded, including fever, cough, nasal discharge, sore throat, wheezing, chest retractions, feeding issues, and breathing difficulties. When clinically necessary, pertinent tests such as a complete blood count, chest X-ray, pulse oximetry, C-reactive protein, and blood culture were carried out in a subset of hospitalised patients. Clinical outcomes, treatment given, hospitalisation requirements, and the severity of the illness were all evaluated and recorded. Inclusion Criteria: • Children aged 0–59 months (under five years). • Children presenting with symptoms and signs suggestive of acute respiratory tract infection. • Both male and female children. • Parents or guardians willing to provide informed consent. • Children attending the outpatient department, inpatient ward. Exclusion Criteria: • Children older than five years of age. • Children with congenital heart disease. • Children with chronic respiratory diseases such as bronchial asthma, cystic fibrosis, or bronchopulmonary dysplasia. • Children with known immunodeficiency disorders. • Children with tuberculosis or chronic pulmonary infections. • Children with incomplete clinical records. • Parents or guardians unwilling to participate in the study. Statistical Analysis: The data that had been entered into Microsoft Excel was analysed using SPSS version 26.0. Continuous data were represented by mean ± standard deviation (SD), whilst categorical variables were represented by frequencies and percentages. To evaluate the relationship between environmental and demographic risk variables and the incidence of lower respiratory tract infections, we employed either Fisher's exact test or the Chi-square test. Continuous variables were compared using the Student's t-test. Age, gender, immunisation status, exposure to home smoking, overcrowding, and nursing history were among the variables analysed. A p-value of less than 0.05 was considered statistically significant..

A total of 30 children under five years of age with acute respiratory tract infections were included in the study. The demographic profile, clinical spectrum, risk factors, and outcomes were analyzed. Table 1: Demographic Characteristics of the Study Population Variable Number (%) Male 18 (60.0) Female 12 (40.0) Age <1 Year 8 (26.7) Age 1–3 Years 14 (46.7) Age 3–5 Years 8 (26.7) Mean Age (Years) 2.4 ± 1.3 Table 1 shows that males constituted the majority of the study population (60.0%). The highest frequency of acute respiratory tract infections was observed in children aged 1–3 years (46.7%). Table 2: Distribution of Acute Respiratory Tract Infections Type of Infection Number (%) Upper Respiratory Tract Infection (URTI) 18 (60.0) Lower Respiratory Tract Infection (LRTI) 12 (40.0) Total 30 (100.0) Table 2 demonstrates that upper respiratory tract infections were more common than lower respiratory tract infections, accounting for 60.0% of cases. Table 3: Clinical Spectrum of Respiratory Tract Infections Clinical Diagnosis Number (%) Common Cold 9 (30.0) Pharyngitis 6 (20.0) Pneumonia 6 (20.0) Bronchiolitis 4 (13.3) Tonsillitis 3 (10.0) Otitis Media 2 (6.7) Total 30 (100.0) Table 3 shows that the common cold was the most frequently diagnosed condition (30.0%), followed by pharyngitis and pneumonia (20.0% each). Table 4: Presenting Symptoms Symptom Number (%) Fever 26 (86.7) Cough 25 (83.3) Nasal Discharge 20 (66.7) Sore Throat 10 (33.3) Difficulty Breathing 10 (33.3) Wheezing 7 (23.3) Feeding Difficulty 5 (16.7) Table 4 demonstrates that fever and cough were the most common presenting symptoms, observed in 86.7% and 83.3% of children, respectively. Table 5: Associated Risk Factors Risk Factor Number (%) Malnutrition 11 (36.7) Incomplete Immunization 8 (26.7) Exposure to Household Smoke 10 (33.3) Overcrowding 12 (40.0) Lack of Exclusive Breastfeeding 9 (30.0) Table 5 shows that overcrowding (40.0%) and malnutrition (36.7%) were the most common risk factors associated with respiratory tract infections.

Acute respiratory tract infections (ARTIs) continue to be a significant public health concern, especially in poor nations, and one of the main causes of morbidity among children under five. The prevalence, clinical range, risk factors, and results of ARTIs among children receiving treatment at a tertiary care facility were assessed in this study. The results showed that respiratory infections are very common in this age range, with upper respiratory tract infections being more common than lower respiratory tract infections [14, 15]. There was a little male majority in the current study, with males making up 60.0% of the sample population. Male children were found to be more vulnerable to respiratory infections due to a combination of biological and environmental variables in earlier paediatric investigations. Children between the ages of one and three had the highest frequency of ARTIs, which may be related to frequent contact with other kids, growing immunity, and greater exposure to infectious agents [16, 17]. Of all cases, 60.0% were upper respiratory tract infections and 40.0% were lower respiratory tract infections. The prevalence of URTIs found in this study is in line with earlier research showing that tonsillitis, pharyngitis, and the common cold account for the bulk of paediatric respiratory infections. However, because they are linked to higher morbidity and frequently necessitate hospitalisation, lower respiratory tract infections including pneumonia and bronchiolitis continue to be clinically significant [18]. The current investigation found a number of modifiable risk variables. Respiratory infections were frequently linked to overcrowding, malnutrition, exposure to home smoke, non-exclusive breastfeeding, and insufficient immunisation. Living in close quarters makes it easier for respiratory diseases to spread, while starvation weakens the immune system and makes people more vulnerable to illness. In a similar vein, exposure to tobacco smoke and indoor air pollution can harm the respiratory mucosa and put kids at risk for repeated respiratory ailments [19]. With proper medical care, the majority of the children in this research fully recovered, and just a tiny percentage needed to be hospitalised. Children with lower respiratory tract infections, especially pneumonia and bronchiolitis, were the main cause of hospital admissions. The benefits of early diagnosis, prompt treatment, and access to tertiary healthcare services are shown in this study's lack of fatality [20]. There are some limitations to the current investigation. The study was carried out at a single tertiary care facility and had a rather small sample size, which may have limited how broadly the results may be applied. Furthermore, not all patients underwent standard microbiological confirmation of the causal infections. To gain a better understanding of the epidemiology and determinants of respiratory tract infections in children under five, larger multicenter studies are needed [21]. The study's conclusions highlight the fact that acute respiratory tract infections are still a leading cause of disease in children. Reducing the burden of respiratory infections and improving child health outcomes requires early detection, timely treatment, and full immunisation, proper nutrition, encouraging breastfeeding, and lowering environmental risk factors [22].

Upper respiratory tract infections are more common than lower respiratory tract infections, and acute respiratory tract infections continue to be a significant cause of morbidity in children under five. Fever and cough were the most frequent clinical manifestations, and the most common diagnoses were pneumonia, pharyngitis, and the common cold. Important risk factors were inadequate immunisation, exposure to home smoking, overcrowding, hunger, and non-exclusive breastfeeding. To lessen the burden of respiratory infections and enhance the health of young children, early diagnosis, proper treatment, immunisation promotion, better nutrition, and elimination of environmental risk factors are crucial.

1. World Health Organization. Acute respiratory infections in children: Case management in small hospitals in developing countries. Geneva: WHO; 2014. 2. McIntosh K. Community-acquired pneumonia in children. N Engl J Med. 2002;346(6):429-37. 3. Rudan I, Boschi-Pinto C, Biloglav Z, Mulholland K, Campbell H. Epidemiology and etiology of childhood pneumonia. Bull World Health Organ. 2008;86(5):408-16. 4. Walker CLF, Rudan I, Liu L, Nair H, Theodoratou E, Bhutta ZA, et al. Global burden of childhood pneumonia and diarrhoea. Lancet. 2013;381(9875):1405-16. 5. Nair H, Simões EA, Rudan I, Gessner BD, Azziz-Baumgartner E, Zhang JSF, et al. Global burden of acute lower respiratory infections due to respiratory syncytial virus in young children. Lancet. 2010;375(9725):1545-55. 6. Jain S, Williams DJ, Arnold SR, Ampofo K, Bramley AM, Reed C, et al. Community-acquired pneumonia requiring hospitalization among U.S. children. N Engl J Med. 2015;372(9):835-45. 7. Kliegman RM, St Geme JW, Blum NJ, Shah SS, Tasker RC, Wilson KM. Nelson Textbook of Pediatrics. 22nd ed. Philadelphia: Elsevier; 2024. 8. Ghai OP, Paul VK, Bagga A. Ghai Essential Pediatrics. 10th ed. New Delhi: CBS Publishers; 2023. 9. Lodha R, Kabra SK. Acute respiratory infections. Indian J Pediatr. 2018;85(1):3-5. 10. Mathew JL, Patwari AK, Gupta P, Shah D, Gera T, Gogia S, et al. Acute respiratory infection and pneumonia in India. Indian Pediatr. 2011;48(3):191-218. 11. Broor S, Pandey RM, Ghosh M, Maitreyi RS, Lodha R, Singhal T, et al. Risk factors for severe acute lower respiratory tract infection in under-five children. Indian Pediatr. 2001;38(12):1361-9. 12. Gupta P, Murali MV, Seth A, Sen D. Epidemiology of acute respiratory infections in children. Indian J Pediatr. 2016;83(12):1448-55. 13. Chisti MJ, Tebruegge M, La Vincente S, Graham SM, Duke T. Pneumonia in severely malnourished children. Lancet Infect Dis. 2009;9(2):117-26. 14. Victora CG, Kirkwood BR, Ashworth A, Black RE, Rogers S, Sazawal S, et al. Potential interventions for prevention of childhood pneumonia. Lancet. 1999;353(9157):935-9. 15. Simoes EAF, Cherian T, Chow J, Shahid-Salles SA, Laxminarayan R, John TJ. Acute respiratory infections in children. In: Disease Control Priorities in Developing Countries. 2nd ed. Washington DC: World Bank; 2006. p. 483-97. 16. Black RE, Morris SS, Bryce J. Where and why are 10 million children dying every year? Lancet. 2003;361(9376):2226-34. 17. Park K. Park's Textbook of Preventive and Social Medicine. 27th ed. Jabalpur: Banarsidas Bhanot Publishers; 2023. 18. Cherry JD, Demmler-Harrison GJ, Kaplan SL, Steinbach WJ, Hotez PJ. Feigin and Cherry's Textbook of Pediatric Infectious Diseases. 9th ed. Philadelphia: Elsevier; 2024. 19. American Academy of Pediatrics. Red Book: Report of the Committee on Infectious Diseases. 33rd ed. Itasca, IL: American Academy of Pediatrics; 2024. 20. World Health Organization. Integrated Management of Childhood Illness (IMCI): Chart Booklet. Geneva: WHO; 2019. 21. Nair H, Nokes DJ, Gessner BD, Dherani M, Madhi SA, Singleton RJ, et al. Global burden of acute lower respiratory infections due to respiratory syncytial virus. Lancet. 2010;375(9725):1545-55. 22. Sharma D, Kuppusamy K, Bhoorasamy A. Prevalence and risk factors of respiratory tract infections among under-five children in developing countries: A review. Int J Pediatr. 2020;2020:1-9.