Seroprevalence of human T-cell lymphoma/leukemia virus type-1 (HTLV-1) antibodies among blood donors at Enugu, Nigeria

Seroprevalence of Human T-cell Lymphotropic Virus Types I/II Among Blood Donors in a Tertiary Hospital in Oman

Objectives

Routine blood donor screening of human T-cell lymphotropic virus (HTLV) has been practiced in Oman since 2017. Limited data exists on HTLV seroprevalence among Omanis. This study aims to determine the seroprevalence of HTLV-I/II among blood donors attending a hospital-based blood bank to assess the need for a universal versus targeted screening.

Methods

We conducted a retrospective review of blood donors' results attending a hospital blood bank between January 2017 and February 2020. Blood samples were screened for HTLV-I/II antibodies using ARCHITECT i2000SR. Reactive samples underwent further testing by immunoblot assay (MP Diagnostics HTLV Blot 2.4). Age, gender, and nationality were assessed. All components manufactured at the blood bank undergo leukoreduction before storage.

Results

A total of 24 469 first-time blood donors were screened for HTLV antibodies. Most participants were male (n = 22 186, 90.7%), and the majority were Omani (n = 22 711, 92.8%). The age range was 18 to 64 years, with a median of 32 years. The seroreactivity rate was 0.2% (43; 95% CI: 0.12-0.23). Confirmatory testing by immunoblot revealed three indeterminate results (7.9%), of which two were Omani and one non-Omani donor, and the remaining 40 seroreactive donors tested negative.

Conclusions

Our study revealed zero seroprevalence of confirmed HTLV among blood donors. The continuation of universal screening for first-time donors is a standard of care. With universal leukoreduction at Sultan Qaboos University Hospital and a very low risk of HTLV in Oman's population, the need for screening regular donors can be reconsidered if these findings are confirmed on a larger scale involving other blood banks in Oman.

Prevalence of human T-lymphotropic virus 1/2 in Nigeria's capital territory and meta-analysis of Nigerian studies

Objectives:

This study was aimed at determining human T-lymphotropic virus 1/2 prevalence among apparently healthy, immunocompromised and haematologic malignant individuals in Nigeria’s capital, as well as meta-analysis of all Nigerian studies until date.

Methods:

A total of 200 participants were recruited into a cross-sectional study. In total, 1 mL each of sera and plasma were obtained from 5 mL blood of each participant and analysed for antibodies to human T-lymphotropic virus 1/2 using enzyme-linked immunosorbent assay; positive samples confirmed with qualitative real-time polymerase chain reaction, followed by statistical and meta-analysis. Sociodemographic characteristics and possible risk factors were assessed via questionnaires.

Results:

Enzyme-linked immunosorbent assay yielded 1% prevalence which was confirmed to be zero via polymerase chain reaction. A total of 119 (59.5%) of the participants were male, while the mean age was 35.28 ± 13.61 years. Apart from sex and blood reception/donation, there was generally a low rate of exposure to human T-lymphotropic virus–associated risk factors. Meta-analysis revealed pooled prevalence of human T-lymphotropic virus 1 and 2 to be 3% and 0%, respectively, from Nigerian studies.

Conclusion:

This study discovered zero prevalence of human T-lymphotropic virus 1/2 from five major hospitals in Nigeria’s capital, exposing the importance of confirmatory assays after positive antibody detection assay results. Meta-analysis highlighted the existence of very few reliable Nigerian studies compared to the demography of the nation. Large-scale epidemiological studies and routine screening of risk populations are therefore needed since Nigeria lies in the region of endemicity.

Serological detection of human T-cell lymphotropic virus types I and II among pregnant women in Ilorin, Nigeria

Human T-cell lymphotropic virus types I/II (HTLV-I/II) is endemic in some parts of the world including Nigeria. Reported prevalence rates in Nigeria have largely focused on blood donors. This study aims at determining the prevalence of HTLV infection among pregnant women in Ilorin North-central Nigeria. Serum samples from 276 pregnant women who were antenatal clinic attendees at General and Civil Service Hospitals in Ilorin were tested for the presence of HTLV-I/II antibodies using Enzyme Linked Immunosorbent Assay test kits from Diagnostic Automation INC., USA. Out of the 276 women tested, 3 tested positive giving a prevalence rate of 1.1%. The result was analyzed on the basis of age, marital status, nature of family, educational status, occupation, religion, parity, and gestational stage of the women. There was no statistical association of HTLV positivity with any of the variables. Although relatively lower than prevalence rate recorded among similar study groups in other parts of the country, the 1.1% prevalence in this study underscores the need for proper education and creation of awareness among antenatal clinic attendees, so as to reduce viral transmission and incidence of HTLV-related diseases.

Molecular Detection and Clinical Implications of HTLV-1 Infections among Antiretroviral Therapy-Naïve HIV-1-Infected Individuals in Abuja, Nigeria

BACKGROUND

Individuals with human T-cell lymphotrophic virus type-1 (HTLV-1)/HIV-1 coinfection have been demonstrated to undergo CD4+ lymphocytosis even in the face of immunodeficiency and increased vulnerability to opportunistic pathogens that can lead to poor prognosis.

OBJECTIVE

This study investigated the prevalence as well as the effects of HIV-1/HTLV-1 coinfection on CD4+ cell counts, routine hematology, and biochemical parameters of study participants.

MATERIALS AND METHODS

This prospective cross-sectional study involved 184 blood samples collected from HIV-1-seropositive individuals attending HIV-special clinic of the University of Abuja Teaching Hospital, Gwagwalada, Nigeria. These samples were analyzed for anti-HTLV-1/2 IgM antibodies using enzyme-linked immunosorbent assay, CD4+ cell counts, and some routine hematological and biochemical parameters. All samples were also tested for HTLV-1 provirus DNA using real-time polymerase chain reaction (PCR) assay.

RESULTS

Of the 184 subjects studied, 9 (4.9%) were anti-HTLV-1/2 IgM seropositive; however, upon real-time PCR testing, 12 (6.5%) had detectable HTLV-1 provirus DNA. The CD4+ cell count was significantly high in HTLV-1-positive (742 ± 40.2) subjects compared to their HTLV-1-negative (380 ± 28.5) counterpart (P-value = 0.025). However, there was no significant association between HTLV-1 positivity with other hematology and biochemical parameters studied (P > 0.05).

CONCLUSION

All subjects (100%) who were HTLV-1/HIV-1-coinfected had normal CD4+ counts. This gives contrasting finding on the true extent of immunodeficiency of subjects. So it is suggested to be very careful in using only CD4+ counts to monitor disease progression and as indicators for antiretroviral therapy (ART) in resource-limited settings. In such conditions, there may be a need to test for HTLV-1 alongside HIV viral loads in order to begin appropriate ART regimens that contain both pathogens.