González J M, Olano V, Vergara J, Arévalo-Herrera M, Carrasquilla G, Herrera S, López J A
Instituto de Inmunología, Universidad del Valle, Cali, Colombia.
Ann Trop Med Parasitol. 1997 Jun;91(4):349-58.
The development of immune responses to malarial infection in inhabitants of endemic areas differs according to the level of exposure to the parasite. Adults living in a region where the level of malaria transmission is low (Colombia) have been shown to exhibit a similar response to each of the three regions of the circumsporozoite protein (the central repeated NANP region, and the flanking N- and C-termini). Conversely, donors exposed to a frequent sporozoite challenge in areas of high malaria transmission (Mali) exhibit antibodies predominantly to the NANP repeated domain. Malaria in the people of Zacarías, a community on the Pacific Coast of Colombia where malaria transmission is low and unstable, was the subject of the present study. Within a 9-year period, a negative correlation between rainfall and documented malaria cases was recorded for this area. Thick smears of blood samples of 319 individuals revealed that 8.5% had malarial infections. As most (67%) of the smear-positive cases were asymptomatic, it seems that, despite the low prevalence of malaria in this area, the establishment of clinical symptoms is attenuated, probably because of the acquisition of premunition. Within this region, the most commonly found Anopheles species (representing 61.1% of the mosquitoes caught) and that giving the highest monthly biting rate (4.0 bites/man) was An. neivai. Most (90%) of the human sera tested possessed antibodies to blood-stage forms of Plasmodium falciparum, and 18% had antibodies to sporozoites. More than half (58%) of the adults had been in contact with hepatitis B virus, 7.2% carried hepatitis B surface antigen, and syphilis was common but no subject was found to be seropositive for HIV. A better understanding of the dynamics of the different elements influencing malaria in areas of low, unstable transmission, such as the one described here, is essential for the design of new malaria-control strategies.
流行地区居民对疟疾感染的免疫反应发展因接触寄生虫的程度而异。生活在疟疾传播水平较低地区（哥伦比亚）的成年人对环子孢子蛋白的三个区域（中央重复的NANP区域以及侧翼的N端和C端）中的每一个都表现出相似的反应。相反，在疟疾高传播地区（马里）频繁受到子孢子攻击的献血者主要产生针对NANP重复结构域的抗体。本研究的对象是哥伦比亚太平洋沿岸疟疾传播低且不稳定的社区萨卡里亚斯居民中的疟疾情况。在9年期间，该地区记录到降雨量与有记录的疟疾病例之间呈负相关。对319人的血样进行厚涂片检查发现，8.5%的人有疟疾感染。由于大多数（67%）涂片阳性病例无症状，所以尽管该地区疟疾患病率较低，但临床症状的出现似乎有所减轻，这可能是由于获得了带虫免疫。在该地区，最常见的按蚊种类（占捕获蚊子的61.1%）且月叮咬率最高（4.0次叮咬/人）的是内瓦按蚊。大多数（90%）检测的人血清含有针对恶性疟原虫血液期形式的抗体，18%的人有针对子孢子的抗体。超过一半（58%）的成年人曾接触过乙肝病毒，7.2%携带乙肝表面抗原，梅毒很常见，但未发现有人HIV血清学呈阳性。更好地了解影响低传播、不稳定传播地区（如此处所述地区）疟疾的不同因素的动态变化，对于设计新的疟疾控制策略至关重要。
