[A molecular epidemiological study of KI polyomavirus and WU polyomavirus in children with acute respiratory infection in Tianjin, China]

Survey of WU and KI polyomaviruses, coronaviruses, respiratory syncytial virus and parechovirus in children under 5 years of age in Tehran, Iran

BACKGROUND AND OBJECTIVES

Severe acute respiratory infections (SARI) remain an important cause for childhood morbidity worldwide. We designed a research with the objective of finding the frequency of respiratory viruses, particularly WU and KI polyomaviruses (WUPyV & KIPyV), human coronaviruses (HCoVs), human respiratory syncytial virus (HRSV) and human parechovirus (HPeV) in hospitalized children who were influenza negative.

MATERIALS AND METHODS

Throat swabs were collected from children younger than 5 years who have been hospitalized for SARI and screened for WUPyV, KIPyV, HCoVs, HRSV and HPeV using Real time PCR.

RESULTS

A viral pathogen was identified in 23 (11.16%) of 206 hospitalized children with SARI. The rate of virus detection was considerably greater in infants <12 months (78.2%) than in older children (21.8%). The most frequently detected viruses were HCoVs with 7.76% of positive cases followed by KIPyV (2%) and WUPyV (1.5%). No HPeV and HRSV were detected in this study.

CONCLUSION

This research shown respiratory viruses as causes of childhood acute respiratory infections, while as most of mentioned viruses usually causes mild respiratory diseases, their frequency might be higher in outpatient children. Meanwhile as HRSV is really sensitive to inactivation due to environmental situations and its genome maybe degraded, then for future studies, we need to use fresh samples for HRSV detection. These findings addressed a need for more studies on viral respiratory tract infections to help public health.

The occurrence of polyomaviruses WUPyV and KIPyV among patients with severe respiratory infections

In 2007, the new polyomaviruses WUPyV and KIPyV were identified in patients with acute respiratory infections. The aim of this study was to investigate these viruses in hospitalized patients with severe acute respiratory infection (SARI). A retrospective study was conducted with 251 patients, from April 2009 to November 2010, using nasopharyngeal aspirates, naso- and oropharyngeal swab samples from hospitalized patients (children < 12 years and adults) who had SARI within 7 days of the onset of symptoms, including fever (> 38.8 °C), dyspnea, and cough. Clinical and epidemiological information was obtained through standardized questionnaire. Enrolled patients were initially suspected to have influenza A(H1N1)pdm09 infections. WUPyV and KIPyV were detected by real-time PCR. Samples were also tested for influenza A and B viruses, human respiratory syncytial virus, rhinovirus, metapneumovirus, coronavirus, adenovirus, and parainfluenza viruses. WUPyV and KIPyV were detected in 6.77% (4.78% and 1.99%, respectively) of hospitalized patients with SARI. All samples from children showed coinfections (rhinovirus was the most commonly detected). Six adults had polyomavirus infection and four (1.6%) had monoinfection. Of them, 3 reported comorbidities including immunosuppression and 1 patient had worse outcome, requiring ICU admission. These preliminary data may suggest a possible role of polyomaviruses in SARI among immunocompromised adult patients.