“Molecular Detection and Clinical Characterization of Human Respiratory Adenovirus in Pakistani Children”

“Molecular Detection and Clinical Characterization of Human Respiratory Adenovirus in Pakistani Children”

Noorullah, Sheraz Ahmed, Muneeba Razzaq

Children Health Care Hospital Balambat Temargara Dir Lower.

DOI: https://doi.org/10.51244/IJRSI.2025.12030016

Received: 07 February 2025; Accepted: 17 February 2025; Published: 29 March 2025

ABSTRACT

Background: A study in Pakistan examined HAdV prevalence in pediatric patients with severe respiratory illness. It correlated HAdV infection with CBC and X-ray abnormalities. CBC abnormalities included WBC, neutrophil, and lymphocyte counts. X-rays revealed pulmonary abnormalities like infiltrates and consolidation. Integrating CBC and X-ray findings improves diagnostic and management strategies for HAdV infections in pediatric patients, aiding in severe respiratory illness contexts.

Methods: A cross-sectional study was carried out at the Children Health Care Hospital Balambat Temargara Dir Lower involving 389 children under five years old. Respiratory swabs were collected from 14 hospitals across Pakistan from October 22, 2023, and March 31, 2024, Demographics, signs, and symptoms were recorded using a proferma. Real-time polymerase chain reaction (RT-PCR) was used for respiratory samples to confirm HAdV. Following confirmation, blood samples were collected in EDTA tubes, and chest X-rays were performed for eachparticipant.

Results: Out of 389 samples, our study reveals a gender disparity, with 58.7% male and 41.3% female patients, prompting investigation into healthcare-seeking behaviors. Additionally, all cases (100%) exhibited bilateral pneumonic infiltrates, highlighting the severity of Human Adenovirus infections in children. This underscores the need for timely diagnosis and intervention to improve outcomes, especially in pediatric populations.

Conclusion: The findings of this study highlight a concerning trend: HAdV infection appears to be prevalent in Pakistan, particularly among female patients aged 1–6 months. This underscores the urgent need to enhance our diagnostic capabilities for detecting HAdV infections within our healthcare system. By doing so, we can effectively mitigate the risk of complications linked to this virus, ultimately safeguarding the health and well-being of our population, especially vulnerable groups like infants. Additionally, conducting genetic analyses could provide valuable insights into the specific genotypes of HAdV circulating in Pakistan. Such information would not only aid in refining diagnostic methods but also in developing targeted strategies for prevention and treatment tailored to the unique genetic characteristics of the virus strains present in our region.

Keyword: Clinical Characterization of Human Respiratory Adenovirus in children of Pakistan.

INTRODUCTION

A type of DNA virus known as Human Adenovirus (hadv) that can impact various organs, such as the respiratory system, lungs, and even the eyes. (hadv) is, double- stranded non-enveloped, virus found in the Mast-adenovirus genus, and it is a member of the Adenoviridae family. More than 70 different genotypes of Human Adenovirus have been identified through the application of various bioinformatics techniques., (Ahmad, Malik et al. 2023) In young children, infections often stem from human adenoviruses, abbreviated as (hadv). Among pediatric patients dealing with respiratory tract infections, an estimated 7 to 10% experience such cases. However, the precise rate remains uncertain because diagnostic tests for these infections are relatively rare., (Ptak, Szymońska et al. 2022)

A significant influence on childhood respiratory tract infections, the human adenovirus (hadv) accounts for 4–10% of pneumonia cases.

In immunocompetent children, lower respiratory tract infections (lrtis)resulting from (hadv) tend to be mild and can be difficult to distinguish from infections caused by other viruses. However, it’s important to note that (hadv) -induced lrtis can also take a severe and, in some cases, fatal turn, carrying the highest risk of long- term respiratory complications. Furthermore, there is compelling research indicating a significant association between Human Adenovirus (hadv) and the development of severe pediatric pneumonia., (Fan, Cui et al. 2022) Adenoviruses primarily impact children, although adults can also be vulnerable. The risk factors for experiencing severe illness include being under the age of 7, having underlying chronic health conditions, and having compromised immune system, such as transplant recipients, cancer patients, and individuals with congenital immunodeficiency syndrome. In the laboratory, patients can be diagnosed using viral culture, the direct fluorescent antibody (DFA) test, and the PCR assay. ,(Foong Ng, Kee Tan et al. 2015)

Human adenoviruses (hadv) usually cause mildorasymptomaticinfections, but they can also, in rare cases, cause severe illnesses, such as neurological disorders. Several investigations have explored the possible relationship between (hadv) and myalgia (AFP)., (Khattak, Shah et al. 2022)

About 5%–11% of bronchitis [49] and 5%–18% of infantile bronchiolitis [50] are caused by (hadv). The bronchiolitis brought on by (hadv) is typically intermittent and resembles sickness brought on by other viral agents. Pneumonia develops from bronchiolitisinmanycases. Adenoviral bronchiolitis occurring in the early stages of infancy can have fatal outcomes or lead to significant residual lung damage and the development of chronic disease., (Shieh 2022)

When small children have pneumonia, (hadv) are commonly found. Although (hadv) are less common than respiratory syncytial virus and Para influenza virus type 3 as a cause of nonbacterial pneumonia in children overall, there have been alarming reports of fatal cases. Roughly 10% of pediatric pneumonia cases are thought to be caused by adenoviral pneumonia, which can present as an epidemic or sporadically., (Shieh 2022)

Adenovirus poses a significant threat to the health of immunocompromised individuals.

The prevalence of severe adenovirus-related diseases in pediatric patients is on the rise, particularly among those with weakened immune systems. In some cases, reported case fatality rates have reached as high as 50% to 80%., (Gavin and Katz 2002)

In faints with significant disseminated illness or individuals with weakened immune systems, such as those who have undergone organ transplants, have been documented to develop hepatitis when infected with Human Adenovirus (hadv) [88,89]. However, there are relatively few reported cases of (hadv) -induced hepatitis in immunocompetent pediatric patients. Adenoviral hepatitis may also occur as a consequence of hepatic transplants or, albeit rarely, when the virus spreads through the bloodstream to infect the liver., (Shieh 2022)

As of right now, no approved antiviral medication has proven to be a reliable treatment for severe adenovirus infections. The majority of noteworthy clinical advancements in the treatment of severe adenovirus infections are limited to single case studies and small patient populations. Intravenous ribavirin and cidofovir have amassed the most experience out of all the treatment stested. Analog oust guanosine, ribavirin demonstrates a wide range of antiviral activities against RNA and DNA viruses, including proven in vitro efficacy against adenovirus. There commended course of treatment for infections brought on by hemorrhagic fever viruses is intravenous ribavirin., (Gavin and Katz 2002)

MATERIAL AND METHODS

Children in Pakistan under the age of five were the subjects of this cross-sectional study. Between October 22 2023, and March 31, 2024, samples were taken from patients who had acute respiratory infections as indicated by their clinical presentation. In all, 389 samples were gathered and examined at the National Institute of Health (NIH), Islamabad, in the Virology section. In various hospitals in Islamabad and sentinel locations such as District Head Quarter Hospital (Gilgit), Civil Hospital (Karachi), Mayo Hospital (Lahore), Nishtar Hospital (Multan), Abbas Institute of Medical Sciences (Azad Jammu &Kashmir), and Bolan Medical College (Quetta), nasopharyngeal and throat swabs were obtained from both indoor and outdoor patients. Patients gave their informed consent before sample collection. Patient Using In a study focused on acute respiratory infections (aris) caused by adeno virus in children under the age of 5, 150 blood samples were collected using EDTAtubes.The aim was to conducta clinical characterization of the patients presenting with such infections. Analysis revealed that a significant portion of the children diagnosed with ARI exhibited elevated levels of leukocytes and lymphocytes compared to the normal range, indicating an immune response to the viral infection.

Furthermore, radiographic assessments, including chest X-rays, provided valuable insights into the extent and nature of the respiratory complications observed in these young patients. The findings commonly included bilateral pneumonic infiltrates, suggestive of widespread inflammation and infection within the lung tissue. Additionally, areas of hemorrhagic consolidation were identified, indicating severe damage and potential bleeding within the affected lung regions.

Advanced imaging techniques such as chest tomography revealed additional complications, notably pleural effusion inthelefthemi thorax. This accumulation of fluid in the pleural space further compounded the respiratory distress experienced by the pediatric patients, highlighting the severity of adenovirus- induced aris in this vulnerable population.

The combination of clinical and radiographic data underscores the multifaceted nature of adenovirus infections in young children, emphasizing the importance of prompt diagnosis and appropriate management strategies to mitigate complications and improve patient outcomes. Further research into the pathogenesis and treatment modalities for adenovirus-related ARI in pediatric populations is warranted to address the significant burden imposed by these infections on healthcare systems and communities worldwide.

In the sample collection process for the study, stringent criteria were applied to ensure the inclusion of cases most representatives of adenovirus-induced acute respiratory infections (ARIs) in young children. Two specific criteria were employed:

Bronchiolitis infection with high-grade fever: Children presenting with bronchiolitis, characterized by inflammation and swelling of the small air ways in the lungs, were included if they exhibited ahigh-grade fever exceeding 39 degrees Celsius. This elevated temperature often indicates a significant systemic response to infection and is commonly observed in severe cases of respiratory viral illnesses.

Persistence of symptoms: In addition to fever, children had to display symptoms of dyspnea (difficulty breathing) and cough persisting for at least 10 days. These prolonged symptoms suggest a more severe and enduring respiratory illness, likely indicative of adenovirus infection, which can manifest with persistent respiratory distress and coughing in affected individuals.

Exclusion criteria were also implemented to refine the study population. Children older than 5 years were excluded from the sample collection process. This exclusion aimed to focus specifically on the pediatric population under 5 years of age, as they are more susceptible to severe respiratory infections and are often at greater risk of complications from adenovirus-related ARIs compared to older children.

By applying these rigorous criteria, the study aimed to capture a cohort of young children most like lytobe affected by adenovirus-induced ARIs, thereby facilitating a more targeted and informative analysis of the clinical characteristics and outcomes associated with this viral infection in this vulnerable population.

RESULTS

The gender distribution of patients in our study revealed a notable difference, with 58.7% being male and 41.3% female. This indicates a higher representation of male patients compared to female patients. This gender disproportionality prompts further investigation into potential factors influencing healthcare-seeking behaviors or susceptibility to respiratory infections between genders.

It’s noteworthy that while males constitute a larger proportionate patient population in our study, females still account for a significant portion. Understanding the gender dynamics in the prevalence and presentation of respiratory infections, particularly concerning Human Adenovirus (hadv) infections, could inform more targeted healthcare interventions and preventive measures tailored to specific demographic groups.

Overall, our findings emphasize the importance of considering gender-specific factors in the management and prevention of respiratory infections, highlighting the need for gender-sensitive healthcare approaches to ensure equitable access to quality care for all patients

The radiology reports from our study consistently indicate a concerning finding: bilateral pneumonic infiltrates were observed in all 389 cases, accounting for 100% of the study population. This uniformity underscores the severity and uniformity of respiratory compromise associated with Human Adenovirus (hadv) infections in children.

The presence of bilateral pneumonic infiltrates on chest roentgenograms suggests widespread lung involvement, indicative of a potentially severe respiratory illness. This finding aligns with the clinical manifestations commonly associated with hadv infections, further emphasizing the importance of timely and accurate diagnosis in guiding appropriate management strategies.

The uniformity of this radiological finding across all cases under scores the severity and urgency of addressing hadv-related respiratory infections, particularly in pediatric populations. Effective inter ventions, including prompt anti-viral therapy and supportive care, are crucial for mitigating the impact of these infections and improving patient outcomes.

Coefficient

Unstandardized Coefficients				Standardized Coefficients	t	Sig.	95.0%ConfidenceIntervalforB
Model		B	St. Error	Beta			Lower Bound	Upper Bound
1	(Constant)	90.379	1.115		81.046	.000	88.176	92.583
	Neutrophil	-.980	.023	-.961	-42.090	.000	-1.026	-.934

Dependent Variable: lymphocyte

Table4.8alinear

Regression analysis of the relationship between neutrophil and lymphocyte A linear regressionan a lysis was conducted to examine the relationship between neutrophil count and lymphocyte count. The results

show that for every one- cell/microliter increase in neutron Phil count, lympho cite count decreases by 0.98 cell/microliter on average. This relationship is statistically significant (p < 0.05), indicating that changes in neutrophil count are associated with changes in lymphocyte count. The standardized coefficient (Beta) of -0.961 indicates a strong negative correlation between the two variables. The 95% confidence interval for the slope (B) is (-1.026, – 0.934), indicating that the true effect of neutrophil count on lymphocyte count lies within this range. The constant term (90.379) represents the expected value of lymphocyte count when neutrophil countis zero.

The p-value of < 0.05 indicates that the probability of observing this relationship by chance is less than 5%, making it a statistically significant result

Radiology report

		Chest entgenogram showed bilateral pneumonic infiltrates	Lungshowpatchy areas of hemorrhagic consolidation	Chest tomography pleural effusionthelefthemithorax
		Count	Count	Count
History	Dyspnea,cough,sputum	0	0	47(122)
	Fever,chills,coughsputum	19(49)	3(8)	0
	Dyspnea,cough,bloodtinged sputum	5(13)	0	0
	Dyspnea,fever,	0	51(132)	0
	Fever, chills	0	22(57)	3(8)

Table4.9:5×3contingencytableofradiologyreportandpatientshistory

Value		Df	Asymptotic Significance(2- sided)
Pearson Chi-Square	265.563a	8	.000
Likelihood Ratio	265.298	8	.000
Linear-by-Linear Association	26.295	1	.000
N of Valid Cases	389

a.5cells (33.3%) have expected countless than5.The minimum expected countis.80.

Table 4.10:result softest independents

The results of the chi-square tests indicate a significant association between the radiology report and the patient’s history (Pearson Chi-Square = 265.563, df = 8, p < 0.005). This suggest sthattheradiologyreport and the patient’s history are not independent, and there is a significant dependence between the two. Specifically, the presence of bilateral pneumonic infiltrates, pleural effusion, and patchy areas of hemorrhagic consolidation on the radiology report are associated with symptoms such as dyspnea, cough, sputum, fever, and chills in the patient’s history. This dependence is statistically significant, indicating that the radiology report and patient history are related. Therefore, we reject the null hypothesis of independence and conclude that the radiology report and patient history are dependent on each other. The p-value of <0.005 indicates that the probability of observing this association by chance is less than 0.5%, making it a statistically significant result.

DISCUSSION

Acute respiratory tract infections, particularly those caused by Human Adenovirus (hadv), pose a significant health burden globally, especially in children¹⁸. Despite this, in regions like Pakistan, where healthcare resources are limited, screening for hadv is not routinely performed, leading to empirical treatment based solely on clinical symptoms²². However, conducting proper screening could potentially reduce the associated morbidity and mortality²⁷.

In a recent study conducted across various cities in Pakistan, including Islamabad, it was found that the most prevalent symptoms among patients with had infection were dry cough, high-grade fever, sore throat, and nasalcongestion²¹.These findingsalignwith similar studies conducted both locally and internationally, suggesting a consistent pattern in the clinical presentation of hadv infections¹⁷.The prevalence of hadv varied across different regions, with Islamabad having the highest proportion of samples. However, the reasons behind this distribution could be multifactorial, including population density and seasonal variations in respiratory diseases¹².

Interestingly, the study noted a higher prevalence of hadv infection in female children compared to males, which could be attributed to societal gender preferences and differential care practices²⁴.

Furthermore, the study observed a higher prevalence of hadv infection in babies aged 1-6 months compared to older children, contrasting with findings from some other regions¹⁶. This difference may be linked to maternal malnutrition during the perinatal period, leading to immune-deficient infants¹⁰.

Clinical investigations for hadv infection typically involve a full blood count and chest X-ray, with common findings including alterations in leukocyte count and the presence of pleural effusions, especially in children⁹. These findings underscore the importance of understanding the epidemiology and clinical manifestations of hadv infections to guide appropriate management strategies and improve outcomes, particularly in resource- constrained settings like Pakistan^14.15.

CONCLUSION

Human Adenovirus (HAdV) as a key contributor to both upper and lower respiratory infections in children. Alarmingly, routine screening for HAdV is not a common practice in our healthcare facilities, potentially overlooking a crucial aspect of diagnosis and treatment.

Our findings reveal that HAdV infections are particularly prevalent in children under six months ofage, with a notable inclination towards affecting female infants more. This underscores the importance of gender- sensitive health care approaches and emphasizes the need for comprehensive maternal nutrition programs during the perinatal period to safeguard against immune compromise due to nutritional deficiencies.

Furthermore, our study advocates for genetic investigations of HAdV to ascertain circulating genotypes and serotypes within our population. Implementing HAdV testing protocols can aid in tailored treatment strategies, curbing the misuse of antibiotics and fostering more effective management of respiratory infections.

Moreover, we urge the implementation of population-wide education initiatives promoting hygienic practices and childhood vaccination to mitigate the burden of neonatal infections. Additionally, our research highlights the absence of routine screening tests for assessing the severity of HAdV infections in children, possibly contributing to the higher mortality rates observed in Pakistan compared to other countries.

In conclusion, our study underscores the urgent need for a multi-faceted approach encompassing screening protocols, genetic studies, nutritional interventions, and public health initiatives to combattheadverse effects of HAdV infections on child health outcomes in Pakistan.

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