COVID 19 infection clinical features in pediatric patients in Southwestern Iran: a cross-sectional, multi-center study

This study assessed the presence of SARS-CoV-2 infection rate using Taq man real-time PCR assay and the epidemiological and clinical data of them, in the southwest of Iran during 17 months of post-pandemic period. The mean age of infected patients was 5.71 years that is consistent with Dong et al.’s study [8]. Global data shows mixed gender distribution of COVID 19, and in our study a slight male predominance was noted (56.2% vs. 44.8%).

13.5% of the suspected patients were confirmed COVID 19 cases, based on positive PCR. The SARS-CoV-2 positive rate in K.B province is higher than in Fars province (21.87% and 10.12%, respectively). The higher rate of COVID 19 infection in K.B province may be due to the particular cultural conditions; more social and interfamilial contacts and large funerals in this particular geographic area. On the other hand, unlike the Fars province, where 20% of the enrolled population was outpatient, K.B province enrolled patients were totally inpatients. Totally, our prevalence was very similar to Hosseininasab et al.’s study in Kerman province of Iran (13.4%). COVID 19 affected children (69%) were more prevalent on admission screening, in the hospital of Karachi in Pakistan [9], unlike our study. The prevalence of SARS-CoV-2 infection in males and females (14% vs. 13%, respectively) was similar and consistent with that of Min Jin’s study [10].

The highest numbers of SARS-CoV-2 suspected children were in the 1 month to 2 year age group, but the most affected children were between 10 and 18 years old (P = 0.003). This high rate of COVID 19 –like respiratory infections in the 1 month to 2 year age group is predictable due to lower efficacy of the immune system. The other factor may be high referral rate of this young children to the health care centers due to their susceptibility. The higher prevalence of COVID 19, in 10–18 years old age, may be due to a number of reasons including increased expression and affinity of ACE-2 receptors that facilitate viral entry [11], decreased pre-existing immunity [12], more social interactions, higher risk of CMV co-infection in older age [13] etc. [14] [15].

According to Dong et al. report more than 90% of COVID 19 affected children were asymptomatic or with mild to moderate symptoms [8]. Other studies in Egypt, China, and United States reported that symptomatic children showed mild symptoms and did not have severe disease or deaths [8, 16, 17].

In consistent with ours’ cough, respiratory complaints, headache, and myalgia were significantly more common in SARS-CoV-2 positive children, in other studies. [18].

In Zhang et al.’s study on Chinese SARS-CoV-2 infected children, the most common symptoms were fever (76%) and cough (62%) [19]. Fever (50%) was the most common clinical characteristic among children with COVID 19 in Karachi, Pakistan, too [9, 20].

Notably and fortunately, the symptoms of those testing negative (having COVID 19 like complaints), were recorded in our study, enabling to measure the sensitivity, specificity, PPV, and NPV of individual symptoms.

Gastrointestinal complaints such as diarrhea, nausea, and abdominal pain were observed in our patients like other studies [19, 21, 22].

The study performed by Parri et al. showed gastrointestinal symptoms in Italian children [23]. Diarrhea, nausea, and abdominal pain were present in children infected with SARS-CoV-2 in Northern Iran [18]. Gastrointestinal complaints were seen in 25% of children in Karachi, Pakistan [9]. Gholami et al. in a systematic review and meta-analysis reported that the percentage of vomiting (10%) and diarrhea (5%) was not very high [24]. A meta-analysis study by Akobeng reported the prevalence of vomiting was 10.3% and diarrhea 12.4%, and generally 22.8% of children had gastrointestinal symptoms [25].

Neurologic complaints including headaches and confusion were reported by some of the children in this study. Also, these neurologic complaints were present in the significant number of children in Northern Iran in the study of Shahbaznejad, et al. [18]. Hong, et al. and Zimmermann and Curtis reported neurologic complications in pediatric COVID 19. However, in Pakistan, neurological complications were low (5%). The common symptoms among children with neurologic complaints were seizures and neuromuscular weakness [9].

In the present study, 26.16% of the patients were transferred to the ICU. In Europe, the rate of PICU admission was 8% [26]. The PICU admission rate in New York City in 46 hospitals was 28% [27]. In another study in Northern Iran, the patients admitted to PICU were 20% [18]. Tagarro et al. reported that among confirmed cases only 16% were transferred to PICU in Spain [28]. However, in children with COVID 19, the exact rate of PICU admission is still unknown. Different PICU admission policies can be the reason of these different results [18]. Also, all articles reveal that, according to the existing knowledge, the severity of disease in children is much less than adults and its cause is unknown [29, 30].

Several studies have also reported an association between comorbidities and COVID 19 infection [26, 31]. Cardiac and circulatory congenital anomalies and type 1 diabetes were the strongest risk factors for severe COVID 19 [32, 33].In our study, pediatric comorbidities included malignancy, chronic neurological disease, cardiovascular disease, liver disease, chronic pulmonary diseases, diabetes, immunosuppressive disease, and kidney disease. SARS-CoV-2 infection is significantly higher in children with cancer and diabetes than in those with other underlying diseases. A study of Omigi et al. showed underlying diseases in younger age, particularly in pre-school aged children, are predictors of disease severity [34,35,36].

Different studies showed that most children with COVID 19 got infected through contact with infected patients or family cluster; 98.69% [29]. All children in Baki’s study had been infected by contact with confirmed COVID 19 family members [16]. Some studies in China reported similar results [37,38,39,40] but in our study only 25.3% of the infected children had positive contact.

Our research showed 5.8% of PCR positive children had a history of recent travel, while some studies revealed a lower rate (0.089%) [29].

In conclusion, 13% of suspected children to COVID 19, confirmed to be affected SARS-CoV-2 infection using real-time PCR assay and 26% of them were admitted to PICU. SARS-CoV-2 infection is significantly higher in children with cancer and diabetes than in those with other underlying diseases. Fever, cough, dyspnea and other respiratory symptoms, headache, and myalgia were significantly more common in SARS-CoV-2 positive children rather than negative children.