Otomaru Hirono, Kamigaki Taro, Tamaki Raita, Okamoto Michiko, Alday Portia Parian, Tan Alvin Gue, Manalo Joanna Ina, Segubre-Mercado Edelwisa, Inobaya Marianette Tawat, Tallo Veronica, Lupisan Socorro, Oshitani Hitoshi
Department of Virology, Tohoku University Graduate School of Medicine, Sendai, Japan.
Department of Life Creation, Nagasaki Women's Junior College, Japan.
Open Forum Infect Dis. 2019 Mar 11;6(3):ofz045. doi: 10.1093/ofid/ofz045. eCollection 2019 Mar.
To develop a more effective vaccination strategy for reducing the impact of respiratory syncytial virus (RSV) infection, especially in young infants (<6 months old), it is necessary to understand the transmission dynamics of RSV.
We conducted a community-based prospective cohort study from 2014 to 2016 in Biliran Province, the Philippines, on children <5 years old. We collected nasopharyngeal swabs from symptomatic children with acute respiratory infection (ARI) during household visits and at health facilities. In households (n = 181) with RSV-positive ARI cases (RSV-ARI), we also identified ARI episodes among other children <5 years old in the same household. In addition, we determined the serial interval to estimate the basic reproduction number ( ), the average number of secondary cases generated by a single primary case.
In the 181 households analyzed, we found 212 RSV-ARI in 152 households with a single case and 29 households with multiple cases, which included 29 1st RSV-ARI and 31 2nd RSV-ARI. We also found possible index cases among children <5 years old in the same household for 29.0% (18 of 62) of young infants with RSV-ARI. The estimated mean serial interval was 3.2 days, and was estimated to be 0.92-1.33 for RSV-A and 1.04-1.76 for RSV-B, which varied between different times (2014 and 2015) and places.
Young infants are likely to acquire RSV infection from older children in the same household. Therefore, vaccination targeting older children might protect infants from RSV infection.
为制定更有效的疫苗接种策略以减轻呼吸道合胞病毒（RSV）感染的影响，尤其是对6个月以下的小婴儿，有必要了解RSV的传播动态。
2014年至2016年，我们在菲律宾比里兰省对5岁以下儿童开展了一项基于社区的前瞻性队列研究。我们在家庭访视和医疗机构中，从患有急性呼吸道感染（ARI）的有症状儿童处采集鼻咽拭子。在有RSV阳性ARI病例（RSV-ARI）的家庭（n = 181）中，我们还确定了同一家庭中其他5岁以下儿童的ARI发作情况。此外，我们确定了传播间隔以估计基本再生数（ ），即单个原发病例产生的二代病例的平均数量。
在分析的181个家庭中，我们在152个单病例家庭和29个多病例家庭中发现了212例RSV-ARI，其中包括29例首例RSV-ARI和31例次例RSV-ARI。我们还在62例患有RSV-ARI的小婴儿中，发现同一家庭中5岁以下儿童中有29.0%（18例）可能为指示病例。估计的平均传播间隔为3.2天，RSV-A的 估计为0.92 - 1.33，RSV-B的 估计为1.04 - 1.76，在不同时间（2014年和2015年）和地点有所不同。
小婴儿很可能从同一家庭中的大龄儿童处感染RSV。因此，针对大龄儿童的疫苗接种可能会保护婴儿免受RSV感染。
