Opportunistic infections (OIs) remain a significant cause of morbidity and mortality among children living with human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS), particularly in sub-Saharan Africa, where access to comprehensive care remains limited. This study investigates the prevalence and associated risk factors of OIs among under-five children receiving care at the University of Ilorin Teaching Hospital (UITH), Oke Oyi, Kwara State, Nigeria. A retrospective and analytical study design was employed, involving the review of medical records and administration of structured questionnaires over a five-year period (2018–2023). A total of 159 HIV-positive children under five years of age were included in the study, with 120 presenting with one or more opportunistic infections. The most prevalent OIs identified were tuberculosis, pneumonia, oral candidiasis, diarrhea, cryptococcal meningitis, severe malaria, and sepsis. Data analysis revealed that factors such as late initiation of antiretroviral therapy (ART), poor nutritional status, low cluster of differentiation 4 (CD4) counts, and poor adherence to treatment were significantly associated with the incidence of OIs. The findings underscore the need for early diagnosis, prompt initiation of highly active antiretroviral therapy (HAART), and strengthened routine monitoring and nutritional support to reduce the burden of OIs in HIV-infected children. This study highlights the importance of tailored interventions to improve health outcomes and reduce HIV-related childhood mortality in resource-limited settings.

Human immunodeficiency virus/acquired immunodeficiency syndrome, Opportunistic Infections, Under-five Children, Antiretroviral Therapy, Prevalence, Risk Factors, Nigeria.

Nigeria accounts for one-third of all new infections among children in the 20 worst-hit countries in sub-Saharan Africa. In 2016, an estimated 37,000 children were newly infected in Nigeria due to mother-to-child transmission. Most of these children acquire HIV from their HIV-infected mothers during pregnancy, at birth, or through breastfeeding. According to the Joint United Nations Programme on HIV/AIDS (UNAIDS), by the end of 2016, 36.7 million people worldwide were estimated to be living with HIV, of which 25.5 million (69.5%) were in sub-Saharan Africa.[1]

In 2016, one million people died from AIDS related illnesses globally, with Nigeria accounting for 160,000 of these deaths. Patients with HIV infection often develop complications and multiple comorbidities, among them opportunistic infections (OIs).[2] Since the outbreak of the HIV pandemic, an estimated 34 million people worldwide have died, with nearly 70% of these deaths occurring in sub-Saharan Africa. The depletion of T-lymphocytes caused by the proliferation of HIV leads to severe immune compromise, allowing usually benign infectious agents to become pathogenic. The relationship between HIV/AIDS and opportunistic infections is rooted in immunosuppression.[3]

HIV infection in children causes a broad spectrum of disease, leading to profound immune suppression. A hallmark of this process is the depletion of cluster of differentiation 4+ (CD4+) lymphocytes, which predisposes patients to various opportunistic infections.[4] Without highly active antiretroviral therapy (HAART), the frequency of opportunistic infections varies with age, pathogen exposure, and the degree of immune suppression. Although HIV is the initial causative agent in AIDS, most morbidity and mortality in AIDS patients result from opportunistic infections that exploit weakened cellular and humoral defense mechanisms.[5] These infections include bacteria, fungi, viruses, and protozoa. Tuberculosis (TB) is the most common life-threatening opportunistic infection affecting people living with HIV/AIDS, according to the World Health Organization (WHO). It is the leading cause of death among HIV-infected individuals in Africa and ranks high globally.[3] Other commonly reported OIs include oral candidiasis, herpes zoster, cryptococcal meningitis, cerebral toxoplasmosis, and cytomegalovirus retinitis. Gastrointestinal infections are also frequent in HIV/AIDS patients, with diarrhea occurring in up to 90% of cases in developing countries.[6] Immune reconstitution inflammatory syndrome (IRIS), initially described in adults but also observed in children living with HIV (CLHIV), can complicate the treatment of OIs when ART is initiated or optimized in patients with acute OIs. Thus, prevention and treatment of OIs in CLHIV remain important even in the ART era.[7]

Statement of problem
According to UNAIDS, by the end of 2016, 36.7 million people worldwide were living with HIV, with 25.5 million residing in sub-Saharan Africa. During the same year, Nigeria recorded 220,000 new infections and 160,000 AIDS-related deaths.[8] There are critical differences between disease progression in children and adults. Due to the immaturity of a child’s immune system, disease progression tends to be more rapid, and each stage lasts for a shorter duration. OIs associated with HIV remain the primary cause of illness and death among HIV/AIDS patients.[5] In India, a survey found that tuberculosis accounted for 28% of OIs among people living with HIV (PLHIV), followed by candidiasis at 18.79%. Other infections, like bacterial respiratory infections, diarrhea, skin infections, and herpes zoster, made up additional cases. In Nigeria, a study conducted in Kebbi State found that out of 1950 patients, 606 (31%) were HIV-positive, and 374 (61%) had one or more OIs, including gonorrhea, ascaris, giardiasis, trichomoniasis, candidiasis, and TB.[9]

OIs lower the quality of life of HIV-infected persons, accelerate progression to full-blown AIDS, reduce response to antiretroviral treatment, increase stigma, and limit the ability to work.[10] Although HAART has significantly reduced the risk of OIs, many patients in resource-poor settings continue to suffer from them due to late diagnosis, sub-optimal use of HAART, poor adherence, drug resistance, poverty, malnutrition, and high exposure to infectious agents.[11] Therefore, assessing the prevalent OIs among HIV-infected children under five years in Ilorin is crucial for designing effective public health interventions.[12]

Objectives of the study
General objective:
To assess the prevalence and associated risk factors of opportunistic infections among HIV-positive children under five years of age attending the University of Ilorin Teaching Hospital (UITH), Oke Oyi, Kwara State, Nigeria.

Specific objectives:

• To identify the common OIs associated with HIV/AIDS among children under five attending UITH Oke Oyi, Kwara State, Nigeria.
• To assess the quantity of OIs associated with HIV/AIDS before, during, and after the institution of HAART.
• To establish a plausible relationship between opportunistic infections and progression of HIV/AIDS among children under five attending UITH Oke Oyi, Kwara State, Nigeria.
• To assess the risk factors of opportunistic infections among children under five years infected with HIV/AIDS attending UITH Oke Oyi, Kwara State, Nigeria.

Research design: This study employed a retrospective and analytical design to assess the prevalence and associated risk factors of opportunistic infections among HIV-positive children under five years of age attending the ART Clinic at the UITH, Oke Oyi, Kwara State, Nigeria. Both qualitative and quantitative data were analyzed.

Research setting: The study was conducted at the UITH, a tertiary healthcare facility located in Ilorin East Local Government Area of Kwara State. UITH provides a range of specialized services, including maternal and child health, antiretroviral therapy, laboratory diagnostics, and emergency pediatric care. The hospital also serves as a referral center for HIV/AIDS management in North Central Nigeria.

Study population: The target population comprised HIV-positive children aged 0–59 months who registered and received ART services at UITH between January 2018 and December 2023.

Sample size determination: The sample size was determined using Yamane’s formula (1967) for a finite population:
Formula
n = N / (1 + N(e²)) (Yamene Taro, 1967)
n= desired sample size for the study
N= population size for the study
e= level of accuracy (95%=0.05, 98%=0.02, 99%= 0.01 ete).
Therefore, using the formula n = N / (1 + N(e²))
n = 159 / (1 + 159(0.05²))
n = 159 / (1 + 159(0.0025))
n = 159 / (1 + 0.3975)
n = 159 / 1.3975
n= 113.774
n= 114 for accuracy and precision, the n is scaled up to 120.
To enhance accuracy and account for potential non-response, the sample size was rounded up to 120 participants.

Sampling technique: A simple random sampling method was used to select 120 under-five HIV-positive children from the hospital records. A sampling frame was developed from the ART clinic register, and participants were selected using a computer-generated random list.

Data collection methods: Data collection involved both primary and secondary sources:

• Primary data were obtained through structured interviews with caregivers and physical assessments of the children using a validated questionnaire.
• Secondary data were extracted from hospital medical records, including ART initiation dates, CD4 counts, adherence reports, nutritional assessments, and diagnosed opportunistic infections within the timeframe of 2018–2023.

Research instrument: The study utilized a structured, pre-tested questionnaire adapted from previous validated tools in HIV-related pediatric research. It covered demographic data, clinical history, ART status, nutritional status, and presence of opportunistic infections.

• The questionnaire was pretested on 15 caregivers at a nearby general hospital in Kwara State, not included in the main study population.
• Content validity was ensured through expert review by pediatricians and public health specialists.
• Reliability was assessed using Cronbach’s alpha, yielding a coefficient of 82, indicating good internal consistency.

Data analysis: Collected data were entered and analyzed using SPSS version 20.

• Descriptive statistics (frequency, percentage, mean, standard deviation) were used to summarize demographic and clinical characteristics.
• Chi-square tests were used to examine associations between categorical variables.
• Binary logistic regression was conducted to identify predictors of opportunistic infections.
• A p-value of <0.05 was considered statistically significant.

Ethical considerations: Ethical clearance for the study was obtained from the human and animal research ethics committee of Kwara State University.

• Informed consent was obtained from each caregiver prior to participation.
• Data confidentiality, privacy, and the right to withdraw at any stage were fully guaranteed.
• All collected data were anonymized and stored securely.

Table 1: Course of presentation of opportunistic infections and management with HAART

Table 1 indicates that the majority of children recruited for the study were male (55.8%), while females accounted for 44.2%. Before the initiation of HAART, 62.5% of the children presented with a single OI, 29.2% had multiple OIs, and only 8.3% had no OIs, highlighting a high pre-treatment burden of infection.

Twelve weeks after initiating HAART, there was a marked improvement: the proportion of children without OIs increased to 50.0%, those with a single OI decreased to 45.8%, and multiple infections decreased to 4.2%. This trend reflects the effectiveness of HAART in reducing OI incidence over time.

Currently, 74.2% of children are free from OIs, while 25.8% have a single OI, and none have multiple infections, demonstrating significant clinical improvement. The most reported OIs were malaria (12.5%), diarrhoea (11.8%), pneumonia (10.5%), malnutrition (8.6%), and oral candidiasis (7.9%). These findings underscore the positive impact of HAART on the health outcomes of HIV-infected children and suggest an ongoing need for sustained treatment and monitoring.

Table 2: Socio-demographic factors, detection, and care support for opportunistic infections

Table 2 presents the socio-demographic characteristics of respondents and care-related information. A majority of caregivers were married (64.2%), followed by widowed (19.2%), single (10.0%), and divorced (6.7%). Most caregivers had three children (41.7%), and the most common housing type was a two-room apartment (65.8%), reflecting modest living conditions.

Regarding economic status, 55.0% of respondents reported a monthly income between ₦20,000 and ₦50,000, suggesting that most lived on a low income. Diagnosis data revealed that over half of the children (52.5%) were diagnosed with HIV between 1 and 2 years prior to the study, and the same percentage had been initiated on HAART within that period.

The majority of children (95.0%) were reported to take additional medications besides antiretrovirals, and the same proportion consistently accepted ARV/prophylaxis. Immunization coverage was high, with 82.5% of the children being vaccinated. Age distribution showed that most children were between 25–36 months (35.8%), followed by 12–24 months (34.2%) and 37–60 months (30.0%).

These findings highlight a population of caregivers primarily in stable marital relationships and of low to moderate income, with good health-seeking behaviors reflected in high immunization rates and adherence to treatment regimens.

Table 3: Clinical assessment of OIs/HIV/AIDS of recruited children

Table 3.0 presents the clinical and immunological profiles of the children recruited. At baseline, 91.7% of the children were in WHO clinical stages 1 or 2, indicating early disease presentation, while only 8.3% were in advanced stages (3 or 4). Prior to the initiation of HAART, 91.7% of the children had CD4 counts above 500 cells/mm³, and only 8.3% had counts below this threshold. After 12 weeks of HAART, immunological improvement was observed: 96.7% of children had CD4 counts ≥500 cells/mm³, with only 3.3% still below the 500-cell mark.

Current CD4 data showed that 100% of the children now have CD4 counts above 500 cells/mm³, reflecting substantial immune recovery since starting HAART. These findings highlight the positive impact of timely antiretroviral therapy on immune restoration among HIV-infected children.

Table 4: Relationship between opportunistic infections and progression of HIV/AIDs

Table 4 above shows the relationship between opportunistic infections and progression to HIV/AIDs with a χ² of 15.184^y and ρ value of 0.001 leading to the null hypothesis been rejected, and alternate hypothesis being sustained because the ρ value is less than significance level of 0.05. In conclusion, we therefore conclude that there is a significant relationship between opportunistic infections and the progression of HIV/AIDs.

Prevalence of opportunistic infections before, during, and after HAART
This study found a high burden of opportunistic infections (OIs) among HIV-infected under-five children before HAART initiation. The most common infections included malaria (12.5%), diarrhoea (11.8%), pneumonia (10.5%), tuberculosis (9.2%), malnutrition (8.6%), and oral candidiasis (7.9%). This pattern is consistent with reports from other Nigerian and international studies, indicating a typical spectrum of pediatric OIs in resource-limited settings. After 12 weeks of HAART, the proportion of children without OIs rose significantly from 8.3% to 50.0%, while those with multiple OIs dropped to 4.2%. At the time of this study, 74.2% of the children were free from OIs, and no child had multiple infections. This decline affirms the effectiveness of HAART in reducing the burden of OIs over time, consistent with WHO reports and research findings.[13,14] These improvements demonstrate not only therapeutic success but also point to the need for early initiation and adherence to ART regimens to achieve optimal clinical outcomes.

Relationship between opportunistic infections and progression to HIV/AIDS
The study showed a statistically significant relationship between the presence of OIs and the progression to AIDS (χ² = 15.184, p = 0.001). Children with multiple OIs were more likely to have progressed to AIDS, confirming that opportunistic infections are key clinical markers of immune deterioration. This aligns with literature showing that declining CD4+ T-cell counts due to untreated HIV infection predispose children to severe OIs.[15] The findings underscore the need for aggressive management of OIs and early ART to curb disease progression.

Similar to the findings by Duru et al.[16] In Imo State, tuberculosis remains a leading co-infection among HIV-positive children, particularly in those not yet initiated on ART. Factors such as low CD4 count and advanced WHO clinical stage significantly influenced TB development (Odds ratio = 6.013). These associations highlight the critical role of timely diagnosis and staging in mitigating co-infections.

Risk factors associated with opportunistic infections
Late diagnosis, delayed HAART initiation, low household income, and advanced clinical staging were found to be major risk factors for OIs in this population. Over 52% of children were diagnosed and initiated on HAART between 1 and 2 years prior, indicating room for earlier intervention.

These findings are supported by Imade et al.[17] and Anejo-Okopi et al.[18], who reported that low CD4 counts, late clinical stage, and short HAART duration increase OI risk. In addition to clinical factors, socioeconomic variables—particularly poverty and overcrowding—emerged as significant determinants. These structural challenges compound the vulnerability of HIV-positive children to OIs in sub-Saharan Africa. This study reinforces that in low-resource settings like Nigeria, addressing socioeconomic barriers is as crucial as medical interventions. Policies aimed at improving early HIV diagnosis, enhancing ART adherence, and reducing poverty-related factors could substantially reduce HIV-related morbidity and mortality among children.

Recommendations: Based on the findings of this study, the following recommendations are proposed to improve the management and prevention of OIs among HIV-infected under-five children:

• Strengthen capacity building in ART clinics: Regular training and mentorship programs should be implemented for healthcare workers to improve the early detection, diagnosis, and management of OIs in pediatric HIV cases.
• Ensure uninterrupted supply of antimicrobials and prophylactic drugs: Government and health agencies should guarantee the steady availability of essential medications for both treatment and prevention of common OIs, including cotrimoxazole and isoniazid (INH) prophylaxis.
• Enhance TB/HIV collaborative programs: Integration of tuberculosis screening and treatment services within pediatric HIV care units should be strengthened to address the high prevalence of TB co-infections.
• Promote early infant diagnosis (EID): Scale up access to early infant diagnosis of HIV through DNA-PCR testing at the community level to facilitate early ART initiation and reduce the risk of developing OIs.
• Implement community-level interventions: Deploy community health workers to conduct household visits, track ART defaulters, educate caregivers, and support timely clinic attendance, particularly in hard-to-reach areas.
• Promote mass health education campaigns: Community-wide sensitization on HIV prevention, recognition of OIs, immunization, nutrition, and hygiene practices should be prioritized to reduce the risk of infections and stigma.
• Introduce and improve HAART adherence monitoring tools: Use digital adherence tools, pill counts, caregiver diaries, and regular follow-ups to monitor and enhance adherence to ART among children.
• Implement socioeconomic support interventions: Provide support systems such as conditional cash transfers, nutritional aid, or health insurance subsidies for low-income families to reduce financial barriers to consistent care.
• Reinforce adherence counseling for caregivers and patients: Ongoing counseling should be institutionalized to educate caregivers on the importance of medication adherence, follow-up visits, and recognizing early symptoms of OIs.
  • Strengthen data monitoring and evaluation systems: Robust data collection and surveillance systems should be established to track ART outcomes, OI trends, and resistance patterns for better clinical and policy decisions.

Opportunistic infections remain a major clinical challenge in pediatric HIV care, despite the availability of HAART. This study demonstrates that early initiation of HAART, coupled with robust monitoring and socioeconomic support, can significantly reduce OI burden and improve clinical outcomes. The findings advocate stronger health system policies that promote early diagnosis, expand access to antiretroviral therapy, and address the broader social determinants of health. Holistic interventions are urgently needed to reduce HIV-related morbidity and mortality among children in Nigeria and similar settings.

I extend my heartfelt appreciation to the management of Taraba State College of Health Technology, Takum, for granting me the invaluable opportunity to study and advance my knowledge. Your commitment to academic excellence and capacity building has played a significant role in shaping my professional path. I am deeply grateful to my beloved wife for her unwavering support, understanding, encouragement, and sacrifices during this period of study. To my children, thank you for being my source of joy and motivation.

To all my lecturers, mentors, colleagues, and friends, I sincerely appreciate your contributions, guidance, and encouragement throughout this journey. Your impact on my academic and personal growth cannot be overstated.

Not reported

Corresponding Author:
Musa D. Kwanchi
Department of Community Health Science
College of Pure and Applied Science, School of Allied Health and Environmental Science, Kwara State University, Malete, Nigeria
Email: dkwanchi@gmail.com

Co-Authors:
Patricia Peter
Department of Community Health Science
College of Pure and Applied Science, School of Allied Health and Environmental Science, Kwara State University, Malete, Nigeria

Ronas Richard
Department of Environmental Health Science
Faculty of Nursing and Allied Health Sciences, University of Abuja, Nigeria

Mal. Sale Mohammed
Department of Community Health Science
Taraba State College of Health Technology, Takum, Nigeria

Musa D. Kwanchi served as the principal investigator and was responsible for the study of design and manuscript presentation. Patricia Peter contributed as a co-investigator and was involved in data collection. Ronas Richard, also a co-investigator, contributed to the literature review. Mal. Sale Mohammed acted as a co-investigator and was responsible for data analysis.

Ethical approval for this study was obtained from the University of Ilorin Teaching Hospital, Ilorin, Nigeria. The hospital management granted permission to collect data for the stated research purpose, as per letter reference UITH/CA/148/Vol.1/93/30 dated 15th July 2022. The data collection was supervised by Dr. H. A. Ameen. All procedures adhered to the institutional ethical guidelines.

The authors declare no conflict of interest.

None

https://doi.org/10.63096/medtigo3062337

Kwanchi MD, Peter P, Richard R, Mohammed MS. Prevalence and Risk Factors of Opportunistic Infections Associated with HIV/AIDS Among Under Five Children Attending University of Ilorin Teaching Hospital Oke Oyi, Kwara State, Nigeria. medtigo J Med. 2025;3(3):e3062337. doi:10.63096/medtigo3062337 Crossref