Epidemiology

HTLV-1

Prevalence

HTLV-I Prevalece The HTLV-I infection is endemic in the Southeast Japan (10), the Caribbean Basin (11), Melanesia (12), and in parts of Africa (13-15). In some regions, where the HTLV-I infection is endemic, the prevalence rate is so high it reaches 15% of the general population. Seroprevalences tend to increase with age; in elderly groups the rates are generally higher among women. In the USA, the HTLV-I/II seroprevalence average rate among volunteer blood-donors is calculated at 0.016% (6).

For the HTLV-I infected donors it has been frequently reported a birth history in endemic countries for the HTLV-I or sexual contact with people from the Caribbean or Japan.

A lower number has been reported with a history of intravenal drug use or blood transfusion. The HTLV-I has also been observed among African-American groups in the Southeast USA (16) and immigrants from HTLV-I-endemic regions, who live in Brooklyn, New York, USA (17). Table 1 shows a brief description of the seroprevalence in some cities in Brazil, with blood-bank diagnosis.

You can verify that the city of Salvador has the higher prevalence of HTLV-I in Brazil, with approximately 4 times the prevalence found in Sao Paulo, for instance.