Epidemiology and pathogenicity of human retroviruses.
The human retroviruses can be divided into oncovirus (HTLV-I and HTLV-II) and lentivirus strains (HIV-1 and -2). The HTLVs are endemic in Central Africa, the Caribbean Islands and in southwest Japan, but now tend to spread through the i.v.-drug user population in the USA and in some countries in Western Europe. HTLV infection is associated with a malignant form of adult T-cell leukemia, tropical spastic paraparesis (TSP) and an associated myelopathy (HAM). The pathogenic mechanisms of HTLV are as yet poorly understood. HIV infection is spreading rapidly almost world-wide and has reached epidemic proportions in Central Africa, parts of South America and in certain populations in industrialized countries that have risk behaviour for contracting venereal or blood-borne infections. The mechanisms of HIV-induced immune suppression are still not entirely clear, as direct T-lymphocyte destruction after viral infection cannot account for the almost complete loss of CD4 T-cells in the final stages of disease. Various indirect mechanisms of HIV-induced immune cell destruction are outlined below.
Paul-Ehrlich-Institut, Langen/Frankfurt.
R
R
Kurth
M
M
Baier
D
D
Binninger
K
K
Cichutek
J
J
Löwer
S
S
Norley
D001688:Biological Products / Q000302:isolation & purification; D006800:Deltaretrovirus Infections / Q000453:epidemiology / Q000209:etiology; D004340:Drug Contamination; D015658:HIV Infections / Q000453:epidemiology / Q000209:etiology; D006801:Humans; D012190:Retroviridae / Q000145:classification / Q000472:pathogenicity*; D012192:Retroviridae Infections / Q000453:epidemiology* / Q000209:etiology / Q000635:transmission
D001688:Biological Products