In the recent years, dengue has been documented in travellers returning from several countries in West Africa, and particularly dengue type-3 virus.

近年来，有文件记载，从西非几个国家回国的旅行者感染了登革热，尤其是3型登革热病毒。

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All four dengue virus (DENV) serotypes were permanently in circulation, though the predominant serotype has alternated between DENV-3 and DENV-2 since 2000.

尽管2000年之后主导血清型在DENV - 3和DENV - 2之间交替，但是全部四种登革热病毒血清型一直在循环着。

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Three tests conducted on 10 May by the Cairo-based US Naval Medical Research Unit 3 (NAMRU-3) confirmed the child’s infection with the H5N1 virus.

设在开罗的美国海军第三医学研究处5月10日进行的3次检测确认了该名儿童感染H5N1病毒。

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Today, on the continent of Africa, nearly 30 million people have the AIDS virus, including 3 million children under the age of 15.

CNN: Transcript of State of the Union

Last year, however, Simonsen and Viggo Andreasen concluded that the true R-naught of the 1918 flu virus was probably somewhere between 3 and 4.

CNN: Scientists dig for lessons from past pandemics

Comparing the two rates of infection, patients taking antiretroviral drugs were 96.3% less likely to pass on the virus.

WSJ: AIDS Study Marks Prevention Breakthrough With Antiretroviral Drugs