Objective Respiratory viruses are the most important cause of lower respiratory tract infections (LRTI) in children. Meteorological factors can influence viral outbreaks. The objective of this study was to determine the association between climate variables and respiratory virus detection.

Methods Multicenter prospective 1-year surveillance was conducted among children hospitalized for LRTI in Tunisia. Nasopharyngeal aspirates were tested by direct immunofluorescence assay (DIFA) for the detection of respiratory syncytial virus (RSV); adenovirus (AdV); influenza virus (IFV) A and B; and parainfluenza virus 1, 2, and 3 (PIV1/2/3). Samples were further analyzed by reverse-transcription polymerase chain reaction for the detection of human metapneumovirus (hMPV). Monthly meteorological data were determined by consulting the National Institute of Meteorology and the World Weather Online Meteorological Company websites. Pearson's correlation tests were used to determine the statistical association between the detection of respiratory viruses and climatic characteristics.

Results Among 572 patients, 243 (42.5%) were positive for at least one virus. The most frequently detected viruses by DIFA were RSV (30.0%), followed by IFVA (3.8%), IFVB (3.5%), PIV (0.9%), and AdV (0.9%). HMPV was detected in 13 RSV-negative samples (3.3%). Dual infections were detected in seven cases (1.2%). Monthly global respiratory viruses and RSV detections correlated significantly with temperature, rainfall, cloud cover, wind speed, wind temperature, and duration of sunshine. Monthly IFV detection significantly correlated with rainfall, wind speed, wind temperature, and duration of sunshine. HMPV detection significantly correlated with temperature and wind temperature.

Conclusion Respiratory viral outbreaks are clearly related to meteorological factors in Tunisia.

目的 呼吸道病毒是儿童下呼吸道感染（LRTI）的最重要原因。气象因素会影响病毒的爆发。这项研究的目的是确定气候变量与呼吸道病毒检测之间的关联。

方法 对突尼斯LRTI住院儿童进行1年多中心前瞻性监测。鼻咽抽吸物通过直接免疫荧光测定法（DIFA）进行检测，以检测呼吸道合胞病毒（RSV）；腺病毒（AdV）；甲型和乙型流感病毒；和副流感病毒1、2和3（PIV1 / 2/3）。通过逆转录聚合酶链反应进一步分析样品，以检测人间质肺病毒（hMPV）。每月的气象数据是通过查询国家气象研究所和世界天气在线气象公司的网站确定的。皮尔逊相关检验用于确定呼吸道病毒的检测与气候特征之间的统计关联。

结果 在572例患者中，至少一种病毒为243例（42.5％）阳性。DIFA最常检测到的病毒是RSV（30.0％），其次是IFVA（3.8％），IFVB（3.5％），PIV（0.9％）和AdV（0.9％）。在13个RSV阴性样本中检出了HMPV（3.3％）。在七例病例中检测到双重感染（1.2％）。全球每月呼吸道病毒和RSV的检测与温度，降雨量，云量，风速，风温和日照时间显着相关。每月检测到的IFV与降雨，风速，风温和日照时间显着相关。HMPV检测与温度和风温显着相关。

结论 突尼斯的呼吸道病毒暴发显然与气象因素有关。