INFLUENZA-VIRUS INFECTIONS IN SEATTLE FAMILIES, 1975-1979 .2. PATTERN OF INFECTION IN INVADED HOUSEHOLDS AND RELATION OF AGE AND PRIOR ANTIBODY TO OCCURRENCE OF INFECTION AND RELATED ILLNESS
INFLUENZA-VIRUS INFECTIONS IN SEATTLE FAMILIES, 1975-1979 .2. PATTERN OF INFECTION IN INVADED HOUSEHOLDS AND RELATION OF AGE AND PRIOR ANTIBODY TO OCCURRENCE OF INFECTION AND RELATED ILLNESS
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DOI：
10.1093/oxfordjournals.aje.a113408
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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;COONEY, MK;FOY, HM
本文分析了1975-1979年西雅图、华盛顿、1976 ~ 1979年的流感病毒家庭，发现在家庭发病中，感染率与年龄和发病前血凝抑制滴度的关系随入侵病毒的不同而不同。在甲型流感/H3 N2事件中，儿童和成人的发病率随着血凝抑制滴度的降低而降低;在相同滴度的情况下，儿童的发病率是成人的两倍;对于所有年龄段，明显的保护需要1：80的滴度。在甲型H1N1流感疫情中，少数滴度为1：>20的儿童和成人，无论滴度如何，通常都能逃脱感染。在B型发作中，没有滴度对儿童具有保护作用;对于成人，滴度1：>20具有57%的保护作用。感染者的患病率随病毒感染的不同而变化不大，在病毒阳性的易感人群中患病率为85%。在A/H3 N2感染中，频率和严重程度与年龄和血凝抑制滴度呈适度（反向）变化，在B型感染中仅与年龄有关，而在A/H1N1病毒中两者均不相关。只有A/H3 N2感染者的发病频率和严重程度与补体结合反应的程度呈负相关。季前水平的抗神经氨酸酶（研究仅与A/H3 N2感染）呈负相关，但弱相关的疾病严重程度，这表明疫苗诱导的抗神经氨酸酶将赋予很少的好处。特定人群的感染率和传入率表明，年幼的学龄儿童（5-9岁）更经常是A/H3 N2流行病的传入者;青少年更可能是B型（可能）和A/H1N1（肯定）病毒的传入者。表观二次发病率仅在成人中因病毒类型而异（A/H3 N2病毒最高，A/H1N1病毒最低）。随着年龄的增长（相反）和如何识别发作（病毒分离时更高），发现了其他变化。虽然父母和学龄前儿童是有效的介绍者，但在所有流行病中，家庭内最丰富的明显交流是在5-19岁之间。这些年龄段的继发性感染率可能由于将许多从社区获得的感染误分类为继发性感染而被夸大。
Influenza virus in Seattle, Washington, families during 1975-1979 were analyzed, and it was found that, in family episodes, the relation of infection rates to age and preepisode hemagglutination-inhibiting titer varied with the invading virus. In influenza A/H3N2 episodes, rates for both children and adults decreased with hemagglutination-inhibiting titers; with equal titers, rates for children were double those for adults; and, for all ages, appreciable protection required a titer of 1:80. In A/H1N1 episodes, the few children with titers of 1:>20 and adults, regardless of titer, generally escaped infection. In type B episodes, no titer was protective for children; for adults, a titer of 1:>20 was 57% protective. Illness frequency among those infected varied little with infecting virus and was 85% in susceptible persons in virus-positive episodes. Both frequency and severity varied modestly (and inversely) with age and hemagglutination-inhibiting titer in A/H3N2 infections, only with age with type B infections, and with neither in A/H1N1 virus. Only with A/H3N2 infections were illness frequency and severity inversely related to magnitude of complement-fixing response. Preseason levels of antineuraminidase (studied only in relation to A/H3N2 infections) were inversely but weakly related to illness severity, suggesting that vaccine-induced antineuraminidase would confer little benefit. Age-specific infection and introduction rates indicated that young school children (5-9 yr) were more often introducers in A/H3N2 epidemics; teenagers were more likely to serve as introducers with type B (probably) and A/H1N1 (definitely) viruses. Apparent secondary attack rates varied with virus type only among adults (highest with A/H3N2 virus and lowest with A/H1N1). Additional variation was found with age (inverse) and with how episodes were recognized (higher when virus was isolated). While parents and preschool children were effective introducers, the most abundant apparent exchange within famlies in all epidemics was among those 5-19 yr of age. Secondary attack rates of these ages probably are inflated by misclassification as secondary of many infections acquired from the community.