Longini Ira M, Yunus Mohammed, Zaman K, Siddique A K, Sack R Bradley, Nizam Azhar
Department of Biostatistics, Rollins School of Public Health, Emory University, Atlanta, Georgia 30322, USA.
J Infect Dis. 2002 Jul 15;186(2):246-51. doi: 10.1086/341206. Epub 2002 Jun 17.
Despite nearly 200 years of study, the mechanisms contributing to the maintenance of endemic cholera and the causes of periodic epidemics remain poorly understood. To investigate these patterns, cholera data collected over 33 years (1966-1998) in Matlab, Bangladesh, were analyzed. Time-lagged autocorrelations were stratified by Vibrio cholerae serogroup, serotype, and biotype. Both classical and El Tor biotypes alternated and persisted between 1966 and 1988; the classical biotype disappeared by 1988, and the O139 serogroup first appeared in 1993. Both the Ogawa and Inaba serotypes circulated the entire time. The autocorrelations revealed that both Inaba and Ogawa epidemics were followed 12 months later by epidemics of the same serotype. Ogawa epidemics, however, were also followed by further Ogawa epidemics only 6 months later. Thus, epidemics of Inaba may selectively confer short-term population-level immunity for a longer period than those of Ogawa. These observations suggest that the Inaba antigen should be maximized in cholera vaccine designs.
尽管经过了近200年的研究，但对于霍乱地方流行的维持机制以及周期性流行的原因，我们仍然知之甚少。为了研究这些模式，我们分析了在孟加拉国马特莱收集的33年（1966 - 1998年）间的霍乱数据。时间滞后自相关按霍乱弧菌血清群、血清型和生物型进行分层。在1966年至1988年间，古典生物型和埃尔托生物型交替出现并持续存在；到1988年古典生物型消失，O139血清群于1993年首次出现。小川型和稻叶型血清型在此期间一直都有传播。自相关分析表明，稻叶型和小川型流行之后12个月，都会出现相同血清型的流行。然而，小川型流行之后仅6个月就会再次出现小川型流行。因此，相较于小川型，稻叶型流行可能会在更长时期内选择性地赋予群体短期免疫力。这些观察结果表明，在霍乱疫苗设计中应最大化稻叶型抗原。
