Evidence of Human Coronavirus-nl63 Infection in Jordanian Children

Objective: To detect and evaluate the role of the newly recognized human coronavirus (HCoV)-NL63 and HCoV-HKU1 as aetiologic agents of acute respiratory tract infections in hospitalized Jordanian children younger than 5 years of age. Methods: Between December 2003 and May 2004, a total of 326 nasopharyngeal aspirates were collected from Jordanian children hospitalized with acute respiratory tract infections. Total DNA and RNA were extracted using Qiagen commercial kits. HCoV-NL63 and HCoV-HKU1 were detected by random reverse transcription-polymerase chain reaction using random hexamer primer for the reverse transcription step, and specific primers that target the replicase and polymerase genes to produce 215-bp and 392-bp amplicons respectively. Other potential respiratory pathogens were detected according to previously published protocols. Results: HCoV-NL63 was detected in 4 (1.2%) out of 325 examined nasopharyngeal aspirates. HCoVNL63 was detected in two children with severe, and in two with mild to moderate acute respiratory tract infections. HCoV-NL63 was the only pathogen detected in three patients, and mixed with adenovirus in one patient. HCoV-HKU1 was not detected in the 325 nasopharyngeal aspirates examined. Conclusion: HCoV-NL63 is a significant causative agent of acute respiratory tract infections in hospitalized Jordanian children. HCoV-NL-63 can cause the respiratory disease either alone or in combination with other potential respiratory pathogens. Further studies are required to further characterize the clinical and epidemiological features of these newly recognized HCoVs in Jordan.