Estimating the Burden of Leptospirosis among Febrile Subjects Aged below 20 Years in Kampong Cham Communities, Cambodia, 2007-2009

BackgroundLeptospirosis is an emerging but neglected public health challenge in the Asia/Pacific Region with an annual incidence estimated at 10–100 per 100,000 population. No accurate data, however, are available for at-risk rural Cambodian communities.MethodWe conducted anonymous, unlinked testing for IgM antibodies to Leptospira spp. on paired sera of Cambodian patients ResultsA total of 630 samples are coming from a randomly selected subset of 2358 samples. IgM positive were found on the convalescent serum sample, among which 100 (15.8%) samples were IgM negative on an earlier sample. Seventeen of these 100 seroconversions were confirmed using a Microagglutination Test. We estimated the probability of having a fever due to leptospirosis at 1. 03% (95% Credible Interval CI: 0. 95%–1. 22%) per semester. In comparison, this probability was 2. 61% (95% CI: 2. 55%, 2. 83%) for dengue and 17. 65% (95% CI: 17. 49%, 18. 08%) for other causes.ConclusionOur data from febrile cases aged below 20 years suggest that the burden of leptospirosis is high in rural Cambodian communities. This is especially true during the rainy season, even in the absence of identified epidemics.研究背景：钩端螺旋体病（Leptospirosis）是亚太地区新兴却长期被忽视的公共卫生挑战，年发病率估计为每10万人10~100例。然而，柬埔寨高风险农村社区暂无准确的流行数据。 研究方法：我们针对柬埔寨患者的配对血清样本，开展了针对钩端螺旋体属（Leptospira spp.）IgM抗体的匿名非关联检测。 研究结果：本次研究共从2358份原始样本的随机抽样子集中纳入630份检测样本。在恢复期血清样本中检出IgM阳性的病例中，100份（占比15.8%）的早期血清样本IgM检测结果为阴性。该100例血清阳转病例中有17例经微量凝集试验（Microagglutination Test）确认。我们估算得出，每半年因钩端螺旋体病引发发热的概率为1.03%（95%可信区间CI：0.95%~1.22%）。相较之下，登革热的该概率为2.61%（95% CI：2.55%~2.83%），其他病因引发发热的概率则为17.65%（95% CI：17.49%~18.08%）。 研究结论：我们针对20岁以下发热病例的研究数据显示，柬埔寨农村社区的钩端螺旋体病疾病负担较高。这一情况在雨季尤为突出，即便未出现明确的暴发疫情。