Familial transmission of human T-cell lymphotrophic virus: silent dissemination of an emerging but neglected infection.

BACKGROUND: HTLV-1 is a retrovirus that causes lymphoproliferative disorders and inflammatory and degenerative diseases of the central nervous system in humans. The prevalence of this infection is high in parts of Brazil and there is a general lack of public health care programs. As a consequence, official data on the transmission routes of this virus are scarce. OBJECTIVE: To demonstrate familial aggregation of HTLV infections in the metropolitan region of Belém, Pará, Brazil. METHOD: A cross-sectional study involving 85 HTLV carriers treated at an outpatient clinic and other family members. The subjects were tested by ELISA and molecular methods between February 2007 and December 2010. RESULTS: The prevalence of HTLV was 43.5% (37/85) for families and 25.6% (58/227) for the family members tested (95% CI: 1.33 to 3.79, P = 0.0033). Sexual and vertical transmission was likely in 38.3% (23/60) and 20.4% (29/142) of pairs, respectively (95% CI: 1.25 to 4.69, P = 0.0130). Positivity was 51.3% (20/39) and 14.3% (3/21) in wives and husbands, respectively (95% CI: 0.04 to 0.63, P = 0.0057). By age group, seropositivity was 8.0% (7/88) in subjects <30 years of age and 36.7% (51/139) in those of over 30 years (95% CI: 0.06 to 0.34, P<0.0001). Positivity was 24.1% (7/29) in the children of patients infected with HTLV-2, as against only 5.8% (4/69) of those infected with HTLV-1 (95% CI: 0.05 to 0.72, P = 0.0143). CONCLUSION: The results of this study indicate the existence of familial aggregations of HTLV characterized by a higher prevalence of infection among wives and subjects older than 30 years. Horizontal transmission between spouses was more frequent than vertical transmission. The higher rate of infection in children of HTLV-2 carriers suggests an increase in the prevalence of this virus type in the metropolitan region of Belém.

Occurrence of strongyloidiasis among patients with HTLV-1/2 seen at the outpatient clinic of the Núcleo de Medicina Tropical, Belém, State of Pará, Brazil.

INTRODUCTION: This study investigated the occurrence of Strongyloides stercoralis infestation and coinfection with HTLV-1/2 in Belém, Brazil. METHODS: S. stercoralis was investigated in stool samples obtained from individuals infected with HTLV-1/2 and their uninfected relatives. RESULTS: The frequency of S. stercoralis was 9% (9/100), including six patients infected with HTLV-1 (14.3%), two patients infected with HTLV-2 (11.1%), and one uninfected relative. Two cases of hyperinfestation by S. stercoralis were characterized as HTLV-1. CONCLUSIONS: These results support the need for the routine investigation of S. stercoralis in patients with HTLV-1, in an attempt to prevent the development of severe forms of strongyloidiasis.

Occurrence of strongyloidiasis among patients with HTLV-1/2 seen at the outpatient clinic of the Núcleo de Medicina Tropical, Belém, State of Pará, Brazil

Introduction This study investigated the occurrence of Strongyloides stercoralis infestation and coinfection with HTLV-1/2 in Belém, Brazil. Methods S. stercoralis was investigated in stool samples obtained from individuals infected with HTLV-1/2 and their uninfected relatives. Results The frequency of S. stercoralis was 9% (9/100), including six patients infected with HTLV-1 (14.3%), two patients infected with HTLV-2 (11.1%), and one uninfected relative. Two cases of hyperinfestation by S. stercoralis were characterized as HTLV-1. Conclusions These results support the need for the routine investigation of S. stercoralis in patients with HTLV-1, in an attempt to prevent the development of severe forms of strongyloidiasis. .