Gorakhpur division consisting of Gorakhpur and neighboring districts Deoria, Kushinagar and Maharajganj in Uttar Pradesh, India, have been witnessing seasonal outbreaks of acute encephalitis syndrome (AES) among children for the last three decades. Investigations conducted during 2005 identified Japanese encephalitis (JE) virus as an aetiology of AES. With the introduction of JE vaccination and other control strategies, the incidence of JE in the region declined, however, outbreaks of acute febrile illness with neurological manifestations continued to occur. Subsequent investigations identified Orientia tsutsugamushi, as the major aetiology of AES outbreaks in the region. This review details clinical, epidemiological, animal and entomological investigations conducted for AES due to O. tsutsugamushi during 2015 and 2017 in Gorakhpur region. Surveillance of acute febrile illness among children attending peripheral health facilities identified scrub typhus as an important aetiology of febrile illness during monsoon and post-monsoon months. Population-based serosurveys indicated high endemicity of scrub typhus. Entomological studies demonstrated natural infection of O. tsutsugamushi in small animal hosts and vector mites. Children acquired this infection through recent exposure to outdoor environment, while playing, or visiting fields or defecating in open fields. A few of the children with scrub typhus progress to develop CNS manifestations. Hence, early administration of appropriate antibiotics is crucial in preventing progression of AFI due to scrub typhus to AES. The investigations conducted by the multi-disciplinary team helped understand the transmission dynamics of scrub typhus in Gorakhpur division and recommend strategies for its control.

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印度戈勒克布尔地区由恙虫病东方体引起的急性脑炎综合征季节性暴发调查：One Health 案例研究

戈勒克布尔地区由印度北方邦的戈勒克布尔和邻近地区德奥里亚、库什纳加尔和马哈拉吉甘吉组成，在过去三十年里，儿童中急性脑炎综合征 (AES) 发生了季节性爆发。2005 年进行的调查确定日本脑炎 (JE) 病毒是 AES 的病因。随着乙脑疫苗接种和其他控制策略的实施，该地区乙脑发病率有所下降，但伴有神经系统表现的急性发热性疾病疫情持续发生。随后的调查确定恙虫病东方体是该地区 AES 暴发的主要病因。本综述详细介绍了 2015 年和 2017 年在戈勒克布尔地区针对恙虫病引起的 AES 进行的临床、流行病学、动物和昆虫学调查。对周边卫生机构就诊的儿童急性发热性疾病的监测发现，恙虫病是季风期间和季风后月份发热性疾病的重要病因。基于人群的血清调查表明恙虫病高度流行。昆虫学研究表明恙虫病在小动物宿主和媒介螨中自然感染。儿童通过最近接触户外环境、玩耍、参观田野或在露天田地排便而感染这种感染。一些患有恙虫病的儿童会出现中枢神经系统症状。因此，早期施用适当的抗生素对于预防由恙虫病引起的 AFI 进展为 AES 至关重要。多学科团队进行的调查有助于了解戈勒克布尔地区恙虫病的传播动态，并提出控制策略。