Musher D M, Groover J E, Rowland J M, Watson D A, Struewing J B, Baughn R E, Mufson M A
Infectious Disease Section, Veterans Affairs Medical Center, Houston, Texas 77030.
Clin Infect Dis. 1993 Jul;17(1):66-73. doi: 10.1093/clinids/17.1.66.
The prevalence of immunity to Streptococcus pneumoniae in the adult population of the United States is unknown. In the study described herein, military recruits had anticapsular IgG antibody to only 15% of common pneumococcal serotypes, whereas working men and elderly men had IgG antibody to 33% and 34% of the common serotypes, respectively (P < .001). Among eight elderly subjects, the prevalence of IgG antibody to capsular polysaccharides increased from 30% to 78% after pneumococcal vaccination; 6 years thereafter, the rate of positive reactions had declined to 58% and IgG levels had declined substantially. With revaccination, IgG levels returned to within (+/-) 40% of the original postvaccination levels. IgM and IgG antibody appeared or began to increase in titer 6 days after vaccination; the rate and degree of response were the same after the first and second exposures. Since most individuals rapidly develop IgG antibody after colonization by S. pneumoniae and since IgG confers immunity, these data suggest that pneumonia is infrequent among healthy adults not because preexisting immunity is widespread but because--with colonization--an immune response develops rapidly, preceding specific events that might lead to infection. Our findings support recommended vaccination procedures and suggest that wider application in subsets of healthy younger adults should be considered.
美国成年人群体中对肺炎链球菌的免疫流行情况尚不清楚。在本文所述的研究中，新兵对仅15%的常见肺炎球菌血清型具有抗荚膜IgG抗体，而在职男性和老年男性分别对33%和34%的常见血清型具有IgG抗体（P <.001）。在八名老年受试者中，肺炎球菌疫苗接种后，对荚膜多糖的IgG抗体流行率从30%升至78%；此后6年，阳性反应率降至58%，且IgG水平大幅下降。再次接种疫苗后，IgG水平恢复到初次接种疫苗后水平的（±）40%以内。接种疫苗6天后，IgM和IgG抗体出现或开始效价升高；首次和第二次接触后的反应速率和程度相同。由于大多数个体在被肺炎链球菌定植后会迅速产生IgG抗体，且IgG可提供免疫力，因此这些数据表明，健康成年人中肺炎罕见并非因为预先存在的免疫力广泛存在，而是因为在定植后会迅速产生免疫反应，先于可能导致感染的特定事件。我们的研究结果支持推荐的疫苗接种程序，并建议应考虑在健康年轻成年人亚组中更广泛地应用。
