INFLUENZA-VIRUS INFECTIONS IN SEATTLE FAMILIES, 1975-1979 .1. STUDY DESIGN, METHODS AND THE OCCURRENCE OF INFECTIONS BY TIME AND AGE
INFLUENZA-VIRUS INFECTIONS IN SEATTLE FAMILIES, 1975-1979 .1. STUDY DESIGN, METHODS AND THE OCCURRENCE OF INFECTIONS BY TIME AND AGE
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DOI：
10.1093/oxfordjournals.aje.a113407
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发表时间：
1982-01-01
影响因子：
5
通讯作者：
FOY, HM
中科院分区：
文献类型：
--
作者：
FOX, JP;HALL, CE;FOY, HM
1975-1979年期间，对西雅图、华盛顿有学龄儿童的家庭进行流感病毒感染的强化监测，包括639个家庭和2732个人观察季节，涵盖4个流感病毒流行季节：B型（1975-1976年）、A/H3 N2型（1975-1976年和1977-1978年）和A/H1N1型（1978-1979年）。1977年（A/H3 N2）、1978年（A/H1N1）和1979年（B型）出现了晚春的感染先驱波，后者预示着1979-1980年的流行。仅通过血清学确认的反季节感染包括每年夏天的B型和A/H3 N2病毒以及1978年的A/H1N1病毒。在流行季节，5-9岁儿童（A/H3 N2）和青少年（A/H1N1和B型）感染率最高。A/H1N1病毒造成了最严重的流行病，在1978-1979年，31%的人口（但只有2%的成年人）感染，72%的家庭受到入侵。相比之下，在B型和2型A/H3 N2流行病中观察到的总体感染率为17-24%，成人感染率为6-13%，家庭入侵率为38-53%。对1965-1969年病毒观察家族的队列长达14年（包括13年的间隔）的扩展观察（主要是血清学的）表明，B型和A/H3 N2型病毒的总感染率分别为13.7和16.4/100人-年，以及第一次和第二次再感染率和第二次再感染率分别为13.7和16.4/100人-年。3和1/100人-年，分别与每种病毒。1975-1979年的密切监测显示，每种流行病毒都有第二次家庭感染，其中37例为A/H3 N2病毒，15例为B型病毒，13例为A/H1N1病毒。这些事件中的感染风险与当前的血凝抑制滴度相关，而不是与初始事件中的经历（感染或未感染）相关，当滴度较低时，67-100%的再感染。在年轻（< 20岁）的成员中，相关疾病与初次感染一样频繁。
Intensive surveillance of Seattle, Washington families with school-age children for influenzavirus infections during 1975-1979 encompassed 639 family- and 2732 person-seasons of observation, covering 4 influenza virus epidemic seasons: type B (1975-1976), type A/H3N2 (1975-1976 and 1977-1978) and type A/H1N1 (1978-1979). Late spring herald waves of infection occurred in 1977 (A/H3N2, 1978 (A/H1N1) and 1979 (type B), the latter presaging an epidemic in 1979-1980. Out-of-season infections, recognized by serology only, included type B and A/H3N2 viruses in each summer and A/H1N1 virus in 1978. In epidemic seasons, infection rates were highest in children aged 5-9 yr (A/H3N2) or in teenagers (A/H1N1 and type B). A/H1N1 virus caused the sharpest epidemic, with 31% of the population (but only 2% of adults) infected and 72% of households invaded in 1978-1979. These compare with infection rates of 17-24% overall and 6-13% of adults and the invasion of 38-53% of households observed in the type B and 2 A/H3N2 epidemics. Extended observation (largely serologic) of a cohort of 1965-1969 Virus Watch families for up to 14 yr (including 1 3-yr gap) indicated overall infection rates of 13.7 and 16.4/100 person-years with types B and A/H3N2 viruses, respectively, and rates of 1st and 2nd reinfections and .apprx. 3 and 1/100 person-years, respectively, with each virus. Close surveillance in 1975-1979 revealed 2nd family episodes of infection with each prevalent virus, 37 with A/H3N2, 15 with type B and 13 with A/H1N1 virus. Risk of infection in these episodes was related more to current hemagglutination-inhibiting titers than to experience (infected or not) in the initial episodes, with 67-100% reinfection when titers were low. Among younger (< 20 yr old) members, related illness was as frequent with reinfection as with initial infection.