Hughes A, Corrah T
Pathology Laboratories, Royal Victoria Hospital, Banjul.
Blood Rev. 1990 Sep;4(3):158-64. doi: 10.1016/0268-960x(90)90043-r.
In the mid 1980's a second human retrovirus, capable of causing the acquired immunodeficiency syndrome (AIDS), was isolated from patients of West African origin. This virus, now called human immunodeficiency virus type 2 (HIV2), was found to be distinct from human immunodeficiency virus type 1 (HIV1) but closely related to simian immunodeficiency viruses (SIV). Although the genomes of HIV1 and HIV2 are similar there are significant differences in nucleotide and amino acid sequences, most marked with the envelope genes and proteins. Both viruses, however, bind to the same CD4 cellular receptor. HIV2 is largely confined to West Africa where it is the dominant HIV, though patients infected with HIV2 have been described in Europe and America. Its transmission, clinical features and immunological effects are similar to those associated with HIV1 infection. However, there is some suggestion that the incubation period from infection to clinical disease may be longer than with HIV1 and that HIV2 may be less pathogenic. Patients with sera that react with both HIV1 and HIV2 antigens have been described, but it is unclear whether this represents serological cross reactivity or true double virus infection. Testing for HIV2 antibodies may become increasingly necessary in HIV2 non-endemic areas.
20世纪80年代中期，一种能够引发获得性免疫缺陷综合征（艾滋病）的第二种人类逆转录病毒，从西非裔患者中分离出来。这种病毒，现在被称为人类免疫缺陷病毒2型（HIV-2），被发现与人类免疫缺陷病毒1型（HIV-1）不同，但与猴免疫缺陷病毒（SIV）密切相关。尽管HIV-1和HIV-2的基因组相似，但在核苷酸和氨基酸序列上存在显著差异，在包膜基因和蛋白质方面最为明显。然而，两种病毒都与相同的CD4细胞受体结合。HIV-2主要局限于西非，在那里它是主要的HIV，但在欧洲和美洲也有感染HIV-2的患者被报道。它的传播、临床特征和免疫效应与HIV-1感染相关的情况相似。然而，有一些迹象表明，从感染到临床疾病的潜伏期可能比HIV-1更长，并且HIV-2的致病性可能较低。已经有血清与HIV-1和HIV-2抗原都发生反应的患者被描述，但尚不清楚这是代表血清学交叉反应还是真正的双重病毒感染。在非HIV-2流行地区，检测HIV-2抗体可能变得越来越必要。
