Department of Public Health, Division of Infectious Diseases/Travel Clinic, Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Hirschengraben 84, Zurich 8001, Switzerland.
Department of Medicine and Diagnostics, Swiss Tropical and Public Health Institute, Socinstrasse 57, Basel 4051, Switzerland.
J Travel Med. 2016 Jun 13;23(5). doi: 10.1093/jtm/taw035. Print 2016 May.
Yellow fever (YF) is a mosquito-borne disease, which can be prevented by vaccination. While YF vaccination (YFV) is not generally recommended for travellers to Tanzania, proof of YFV may be required upon arrival. In April 2013, the World Health Organization concluded that one dose of YFV confers lifelong protection and countries have started to adapt their entry requirements. The traveller's consultant has to balance the risk of YFV and the risk of encountering problems when entering a country without a valid YFV, especially because countries are slowly implementing the requirements.
We performed a survey among 421 travellers to Tanzania with a pre-travel consultation at the Travel Clinic of the University of Zurich about their experiences with YFV certificate inspections upon arrival in Tanzania between January and November 2015.
There were three main findings: (i) most vaccine card checks were done while crossing the land border of Tanzania. Inspections were frequently conducted at Arusha airport, less often in Dar es Salaam and Zanzibar. In the latter a significantly larger percentage of individuals arriving by ferry/boat were checked than those arriving by plane. (ii) Checks appeared to be non-systematic. They were also performed in travellers who did not enter Tanzania from a YF-endemic country. No seasonal or daytime pattern could be identified; the thoroughness of checks varied widely. (iii) In the case of travel without valid YFV, an exemption certificate was always accepted. In travellers with neither a valid YFV nor an exemption certificate, travellers reported forced YF vaccination and fines before entry was granted.
We recommend YFV or a YF exemption certificate for all travellers to Tanzania until further notice. The decision of whether to vaccinate against YF or to issue an exemption should be based on exposure risk to YF infection in other countries during travel.
黄热病（YF）是一种通过蚊子传播的疾病，可以通过接种疫苗来预防。虽然坦桑尼亚通常不建议旅行者接种 YF 疫苗，但入境时可能需要提供 YFV 疫苗接种证明。2013 年 4 月，世界卫生组织得出结论，一剂 YFV 可提供终身保护，各国已开始调整入境要求。旅行顾问必须权衡 YFV 风险和在没有有效 YFV 的情况下进入一个国家遇到问题的风险，特别是因为各国正在逐步实施这些要求。
我们对在苏黎世大学旅行诊所进行坦桑尼亚旅行前咨询的 421 名旅行者进行了一项调查，了解他们在 2015 年 1 月至 11 月期间抵达坦桑尼亚时 YFV 证书检查的经历。
有三个主要发现：（i）大多数疫苗卡检查都是在跨越坦桑尼亚陆地边界时进行的。在阿鲁沙机场经常进行检查，在达累斯萨拉姆和桑给巴尔则较少进行检查。在后者，乘船/乘船抵达的人比乘飞机抵达的人更有可能接受检查。（ii）检查似乎没有系统性。它们也在没有从黄热病流行国家进入坦桑尼亚的旅行者中进行。没有发现季节性或日间模式；检查的彻底性差异很大。（iii）在没有有效 YFV 旅行的情况下，始终接受豁免证书。对于既没有有效 YFV 也没有豁免证书的旅行者，报告称在入境前被迫接种 YF 疫苗并被罚款。
我们建议所有前往坦桑尼亚的旅行者在另行通知之前接种 YFV 或获得 YF 豁免证书。是否接种 YF 疫苗或签发豁免证书的决定应基于旅行期间在其他国家感染 YF 的风险。
