Center for Global Health, CDC, 4770 Buford Highway N.E., MS F-22, Atlanta, GA 30341, USA.
MMWR Surveill Summ. 2011 Apr 8;60(2):1-11.
PROBLEM/CONDITION: Cyclosporiasis is an enteric disease caused by the parasite Cyclospora cayetanensis. Cyclosporiasis is reported most commonly in tropical and subtropical regions. In the United States, outbreaks of cyclosporiasis associated with various types of imported fresh produce have been documented and described since the mid-1990s. No molecular tools are available for linking C. cayetanensis cases. National data regarding laboratory-confirmed sporadic cases (i.e., cases not linked to documented outbreaks) have not been summarized previously.
This summary includes laboratory-confirmed sporadic cases that occurred during 1997-2008 and were reported to CDC by 2009.
In January 1999, cyclosporiasis became a nationally notifiable disease, and, as of 2008, it was a reportable condition in 37 states, New York City (NYC), and the District of Columbia. For 1997-2008, CDC was notified of laboratory-confirmed cases via two active surveillance systems (the Cyclospora Sentinel Surveillance Network and the Foodborne Diseases Active Surveillance Network), two passive systems (the National Notifiable Diseases Surveillance System and the Public Health Laboratory Information System), and informal mechanisms (e.g., electronic mail).
CDC was notified of 1,110 laboratory-confirmed sporadic cases of cyclosporiasis that occurred during 1997-2008. The overall population-adjusted incidence rates ranged from a low of 0.01 cases per 100,000 persons in 1997 to a high of 0.07 in 2002. Of the 1,110 cases, 849 (76.5%) were reported by seven states: 498 (44.9%) occurred in residents of Florida (228 cases), NYC (200 cases), and elsewhere in New York state (70 cases); and >50 cases were reported by each of five other states (Connecticut, Georgia, Massachusetts, New Jersey, and Pennsylvania). Overall, the case-patients' median age was 44 years (range: 3 months-96 years); 50.5% were female, 47.2% were male, and the sex was unknown for 2.3%. A total of 372 case-patients (33.5%) had a documented history of international travel during the 2-week period before symptom onset or diagnosis, 398 (35.9%) reported no international travel, and 340 (30.6%) had an unknown travel history. Some details about the travel were available for 317 (85.2%) of the case-patients with a known history of international travel; 142 (44.8%) had traveled to Mexico (60 persons), Guatemala (44 persons), or Peru (38 persons). Among the 398 case-patients classified as having domestically acquired cases, 124 persons (31.2%) lived in Florida, and 64 persons (16.1%) lived either in NYC (49 persons) or elsewhere in New York state (15 persons). The majority (278 [69.8%]) of onset or diagnosis dates for domestically acquired cases occurred during April-August.
Approximately one third of cases occurred in persons with a known history of international travel who might have become infected while traveling outside the continental United States. Domestically acquired cases were concentrated in time (spring and summer) and place (eastern and southeastern states): some of these cases probably were outbreak associated but were not linked to other cases, in part because of a lack of molecular tools.
Surveillance for cases of cyclosporiasis and research to develop molecular methods for linking seemingly sporadic cases should remain U.S. public health priorities, in part to facilitate identification and investigation of outbreaks and to increase understanding of the biology of Cyclospora and the epidemiology of cyclosporiasis. Unidentified, uninvestigated cases and outbreaks represent missed opportunities to identify vehicles of infection, modes of contamination, and preventive measures. Travelers to known areas of endemicity should be advised that food and water precautions for Cyclospora are similar to those for other enteric pathogens, except that this parasite is unlikely to be killed by routine chemical disinfection or sanitizing methods. The diagnosis of cyclosporiasis should be considered for persons with persistent or remitting-relapsing diarrheal illness, and testing for Cyclospora should be requested explicitly.
问题/情况： 腹泻是一种由寄生虫环孢子虫引起的肠道疾病。腹泻最常发生在热带和亚热带地区。在美国，自 20 世纪 90 年代中期以来，已经记录并描述了与各种类型的进口新鲜农产品有关的腹泻爆发事件。目前还没有可用于将环孢子虫病例联系起来的分子工具。关于实验室确诊的散发病例（即与记录的爆发无关的病例）的国家数据以前没有进行过总结。
本摘要包括 1997-2008 年发生的实验室确诊散发病例，并由 2009 年向疾病预防控制中心报告。
1999 年 1 月，腹泻成为全国法定报告疾病，截至 2008 年，37 个州、纽约市（NYC）和哥伦比亚特区已将其作为报告疾病。对于 1997-2008 年，疾病预防控制中心通过两个主动监测系统（环孢子虫监测网络和食源性疾病主动监测网络）、两个被动系统（国家法定传染病监测系统和公共卫生实验室信息系统）以及非正式机制（例如，电子邮件）收到实验室确诊病例的通知。
疾病预防控制中心接到 1110 例实验室确诊的腹泻散发病例报告，这些病例发生在 1997-2008 年期间。总的人口调整发病率范围从 1997 年的每 100000 人 0.01 例的低水平到 2002 年的 0.07 例的高水平。在这 1110 例病例中，有 849 例（76.5%）由七个州报告：佛罗里达州（228 例）、NYC（200 例）和纽约州其他地区（70 例）的居民报告了 498 例（44.9%）；其他五个州（康涅狄格州、佐治亚州、马萨诸塞州、新泽西州和宾夕法尼亚州）每州报告了超过 50 例病例。总的来说，病例患者的中位年龄为 44 岁（范围：3 个月-96 岁）；50.5%为女性，47.2%为男性，2.3%的性别未知。共有 372 例病例患者（33.5%）在症状出现或诊断前的两周内有记录的国际旅行史，398 例（35.9%）报告没有国际旅行，340 例（30.6%）旅行史未知。对于有已知国际旅行史的病例患者中，有 317 例（85.2%）提供了有关旅行的一些详细信息；142 例（44.8%）前往墨西哥（60 人）、危地马拉（44 人）或秘鲁（38 人）。在 398 例被归类为国内获得的病例患者中，有 124 人（31.2%）居住在佛罗里达州，有 64 人（16.1%）居住在纽约市（49 人）或纽约州其他地区（15 人）。大多数（278 例[69.8%]）国内获得的病例的发病或诊断日期发生在 4 月至 8 月。
大约三分之一的病例发生在有已知国际旅行史的病例患者中，这些患者可能在境外旅行时感染。国内获得的病例集中在时间（春季和夏季）和地点（东部和东南部各州）：其中一些病例可能与爆发有关，但由于缺乏分子工具，无法与其他病例联系起来。
对腹泻病例的监测和开发用于将看似散发性病例联系起来的分子方法应仍然是美国公共卫生的重点，部分原因是为了便于识别和调查爆发事件，并增加对环孢子虫生物学和腹泻流行病学的了解。未识别和未调查的病例和爆发是发现感染媒介、污染模式和预防措施的错失机会。应告知前往已知流行地区的旅行者，环孢子虫的食物和水预防措施与其他肠道病原体相似，只是这种寄生虫不太可能被常规化学消毒或消毒方法杀死。对于持续或缓解-复发腹泻性疾病的患者，应考虑诊断为腹泻，应明确要求进行环孢子虫检测。
