The first survey of human T-cell lymphotropic viruses (HTLV) in HIV/AIDS patients in Santa Catarina State, Brazil

Abstract

Santa Catarina is a Brazilian State that has reported the lowest prevalence of human T-cell lymphotropic viruses (HTLV-1/2) in blood donors (0.04%). Although it presents ports, airports and roads that facilitate the entrance and dissemination of new infectious agents, no information exists concerning the HTLV-1/2 infections in HIV/AIDS patients. This study searched for HTLV-1/2 antibodies in plasma samples of 625 HIV/AIDS patients from the municipality of Tubarao (Southern Santa Catarina), and disclosed 1.1% of positivity (0.48% HTLV-1, 0.48% HTLV-2 and 0.16% untypeable HTLV), and a positive correlation with the male sex (OR 4.16) and intravenous drug use (OR 35.18). Although the percentage of 1.1% appears to be low, it is 27.5 times higher than the percentage detected in blood donors. Since HTLV-1 and HTLV-2 are circulating in HIV-infected individuals in Southern Santa Catarina, and these retroviruses could cause a differently impact on the HIV/AIDS outcomes, the surveillance of HTLV-1/2 is necessary, and it could support public health policies in preventing the transmission and dissemination of these viruses in this State.

The challenge of describing the epidemiology of HTLV in the Amazon region of Brazil

“…The history of HTLV is a fascinating one regarding its possible origin in the African continent and its spread in different directions according to human migration routes [4], and the ARB is of paramount importance because of the presence of a specific strain of the virus that originated during human migration into the area and its further dissemination to other geographical areas in the country and abroad [36,51,[91][92][93][94][95][96][97].…”

Pooling of sera for human T-cell lymphotropic virus (HTLV) screening in a time of increasing health care expenditure and limited resources

“…Finally, the 625 positive serum samples of HIV/AIDS were grouped into 125 pools; eight were EIA positive; therefore, 125 reactions plus 40 reactions, total of 165 reactions instead of 625 reactions, with a cost minimization of 73.6% ( Figure 3C). Of note, in HIV/AIDS, one of the eight reactive pools was capable of detecting a borderline OD/CO sample identified previously in individual analysis, and this sample did not confirm HTLV-1/2 infection by Western Blot and INNO-LIA 19 .…”

“…After validating the five-sample pool using EIA Murex, the technique was employed for individual cost comparison in 2,625 serum samples previously screened, of which the final HTLV confirmatory results were published elsewhere: 1,300 from patients with hepatitis B, 700 with hepatitis C, and 625 with HIV/AIDS 19,20 . The results from individual and pooled samples confirmed the diagnostic sensitivity (100%) and specificity (100%) of the pooling (Cohen's Kappa = 1.0), and a cost minimization of 70.4%, 60.7% and 73.6% in these populations (Figure 3), depending on Murex and Gold ELISA assays according to the manufacturer's instructions; *Serum sample dilution in blood donor bags negative for all blood-borne infectious agents; OD/CO = optical density-to-cut off ratio; H = high reactive sample by EIA; L = low reactive sample by EIA.…”

“…In bold, the highest serum dilutions without loss of reactivity in low reactive samples. the prevalence of HTLV-1/2 (1.9% in HBV, 4.0% in HCV, and 1.1% in patients with HIV/AIDS) 19,20 . Briefly, the 1,330 HBV positive serum samples were grouped into 260 pools; HTLV-1/2 screening disclosed 25 HTLV-positive pools.…”

“…Finally, for calculating the diagnostic sensitivity and specificity and the cost minimization of the HTLV-1/2 screening using individual samples and pooled samples, 2,000 serum/plasma samples from patients with viral hepatitis B and C and 625 plasma samples from patients with HIV/AIDS that had been individually screened using the same EIA, of which the results had been published elsewhere 19,20 , were employed. The cost minimization in percentage was calculated considering the value in American dollars (U$ 1.5 per reaction) in the EIA acquired in 2019.…”