Frequency of human immunodeficiency virus type-2 in hiv infected patients in Maputo City, Mozambique

HIV-1/2 differentiation in a South African public laboratory

Background

The human immunodeficiency virus type-2 (HIV-2) prevalence in South Africa (SA) is unknown, however, sporadic cases have been reported. Human immunodeficiency virus -1 and 2 differentiation is not part of most South African public laboratories’ testing algorithm. Human immunodeficiency virus -2 diagnosis using serology assays may be complicated by HIV-1 and HIV-2 antibody cross-reactivity.

Objectives

To determine the proportion of HIV-2 infections in specimens that tested HIV-1/2 positive at a public laboratory in Tshwane.

Method

A total of 480 specimens that were previously tested with fourth generation ELISA platforms (Modular E170 [Roche, Switzerland] and Architect i2000 [Abbott, Germany]) were randomly selected. Human immunodeficiency virus -1 and 2 antibody differentiation testing was carried out using the Multispot HIV-1/2 rapid assay (Bio-Rad Laboratories, USA). An in-house nested HIV-2 PCR assay targeting the 5′-long terminal repeats (5′-LTR) region was evaluated and used as a confirmatory test.

Results

The study tested 480 HIV-1/2 seropositive patients and their mean age was 36.7 years (range 3–82 years). Of the 480 patients, 292 (60.8%) were female, 182 (37.9%) were male and 6 (1.3%) were not specified. Human immunodeficiency virus differentiation results were as follows: 466 (97.1%) were positive for only HIV-1 antibodies, 11 (2.3%) [95%CI: (0.98%; 3.74%)] were positive for both HIV-1 and HIV-2 antibodies, 3 (0.6%) were negative for both antibodies and none were positive for only HIV-2 antibodies. Of the 11 specimens with both HIV-1 and HIV-2 antibodies, seven had sufficient volume for confirmatory testing and were all negative on the in-house HIV-2 PCR assay.

Conclusion

The multispot HIV-1/2 rapid assay demonstrated cross-reactivity between HIV-1 and HIV-2 antibodies. Human immunodeficiency virus -2 infections were not detected.

The performance of a new point-of-care HIV virus load technology to identify patients failing antiretroviral treatment

BACKGROUND

A new point-of-care (POC) HIV virus load technology has been recently developed and designed to be utilized in decentralized settings. Alere Technologies GmbH*, Germany, developed the mPIMA HIV-1/2 VL plasma test which uses real time PCR technology with 50 μl and a turnaround time of one hour.

OBJECTIVE

Analyze the performance of mPIMA to detect and quantify HIV-1 and HIV-2 and compare with Abbott M2000 assay fooling patients HIV-1 failing ARV therapy.

STUDY DESIGN

In this study we evaluate the mPIMA HIV-1/2 VL plasma test using 413 specimens from 270 patients failing ARV therapy, and compared its performance with Abbott RealTime HIV-1 Viral Load assay on the m2000 system. In addition, were determined VL in plasma specimens obtained from HIV-2 infected patients.

RESULTS

The results strongly indicate that mPIMA HIV-1/2 VL plasma test can determine HIV-1 with concordance of 88.9 % (95 % CI 85.4-91.7) the reference test when 1000 HIV-1 VL threshold was used as WHO cutoff to identify therapy failure. The overall correlation between HIV-1 VL was 0928 (Pearson correlation coefficient of Linear regression) and the Bland-Altman showed a mean difference of -0.20 Log cp/mL between the two technology. mPIMA HIV-1/2 VL plasma test was also able to measure HIV-2 viral load in 16 specimens from Guinea-Bissau HIV-1/HIV-2 positive samples.

CONCLUSIONS

These data support the use of mPIMA HIV-1/2 VL plasma test to follow up patients and select patients failing ART, guiding immediate clinical decisions such as adherence counseling or ART regimen switch during the patient consultation.

Problems encountered in conventional HIV 1/2 Algorithms: lack of necessity for immunoblot assays to confirm repeated ELISA reactive results

BACKGROUND

The use of conventional (serologically based) HIV 1/2 diagnostic algorithms has become controversial in recent years.

OBJECTIVES

Sera from patients who underwent verification tests were evaluated because repeated ELISA-reactive results demonstrated a HIV1+HIV2 positive band pattern.

METHODS

The line immunoassay (LIA) test was used for repeated HIV enzyme immunoassays (EIA)-reactive sera in patients at three centers. The Bio-Rad Geenius™ HIV 1/2 and the HIV-1 RNA tests were used. HIV-1 and RNA HIV-2 were investigated using PCR.

RESULTS

LIA was used to evaluate 3,224 out of 10,591 samples with repeated ELISA reactivity (30%). We found that 32 (1%) of the sera, along with HIV1 bands and HIV2 gp36 bands, were positive. Only 28 of the 32 verified serum samples with gp36 bands were repeated, and no gp36 band positivity was detected using the Bio-Rad Geenius™ HIV-1/2 confirmatory assay in these serum samples. The HIV-2 proviral DNAs were also negative. Therefore, we excluded the possibility of HIV1+2 co-infection. All samples from the 32 patients were positive for HIV-1 RNA.

CONCLUSION

Our findings highlight the need to exclude confirmatory tests like the LIA test from the current diagnostic HIV algorithm and replace it with rapid HIV-1 and HIV-2 confirmatory immunochromotographic tests.

The challenge of discriminating between HIV-1, HIV-2 and HIV-1/2 dual infections

OBJECTIVES

Discrimination between HIV-1 and HIV-2 is important to ensure appropriate antiretroviral treatment (ART) and epidemiological surveillance. However, serological tests have shown frequent mistyping when applied in the field. We evaluated two confirmatory tests, INNO-LIA HIV I/II Score and ImmunoComb HIV 1/2 BiSpot, for HIV type discriminatory capacity.

METHODS

Samples from 239 ART-naïve HIV-infected patients from the Bissau HIV Cohort in Guinea-Bissau were selected retrospectively based on the initial HIV typing performed in Bissau, ensuring a broad representation of HIV types. INNO-LIA results were interpreted by the newest software algorithm, and three independent observers read the ImmunoComb results. HIV-1/HIV-2 RNA and DNA were measured for confirmation.

RESULTS

INNO-LIA results showed 123 HIV-1 positive samples, 69 HIV-2 positive and 47 HIV-1/2 dually reactive. There was agreement between INNO-LIA and HIV-1/HIV-2 RNA and DNA detection, although not all HIV-1/2 dually reactive samples could be confirmed by the nucleic acid results. Overall, the observers found that the ImmunoComb results differed from the INNO-LIA results, with agreements of 90.4, 91.2 and 92.5%, respectively, for HIV-1, HIV-2 and HIV-1/2. The combined kappa-score for agreement between the three observers was 0.955 (z-score 35.1; P < 0.01). Of the HIV-2 mono-reactive samples (INNO-LIA), the three observers interpreted 24.6-31.9% as HIV-1/2 dually infected by ImmunoComb. None of these samples had detectable HIV-1 RNA or DNA.

CONCLUSIONS

There was accordance between INNO-LIA calls and nucleic acid results, whereas ImmunoComb overestimated the number of HIV-1/2 dually infected patients. Confirmatory typing is needed for patients diagnosed with HIV-1/2 dual infection by ImmunoComb.

Hiv-2 molecular epidemiology

The Simian Immunodeficiency Virus of sooty mangabeys (SIVsmm) has been revealed to be at the origin of Human Immunodeficiency Virus type 2 (HIV-2) in humans, firstly detected from two Portuguese patients in 1986. HIV-2 is mainly restricted to West Africa where it infects up to 1 to 2 million people. HIV-2 is also present in Europe, mainly Portugal and France, India and United States of America. Two major HIV-2 groups, groups A and B, were generated by two independent transmission events involving infected sooty mangabeys from the Taï forest in Ivory Coast. Seven other HIV-2 groups have been described, but each has only been identified in one patient. To date, no subtypes have been formally described but some preliminary data suggest that HIV-2 group A may be divided in two distinct subtypes with distinct geographical origins. To date only two recombinant forms have been described: one circulating recombinant form (CRF01_AB) and one unique recombinant form. In this review, we focused mainly on molecular data available and their insights about HIV-2 origins, diversity, drug resistance and global epidemiology.

Infection with human retroviruses other than HIV-1: HIV-2, HTLV-1, HTLV-2, HTLV-3 and HTLV-4

HIV-1 is the most prevalent retrovirus, with over 30 million people infected worldwide. Nevertheless, infection caused by other human retroviruses like HIV-2, HTLV-1, HTLV-2, HTLV-3 and HTLV-4 is gaining importance. Initially confined to specific geographical areas, HIV-2, HTLV-1 and HTLV-2 are becoming a major concern in non-endemic countries due to international migration flows. Clinical manifestations of retroviruses range from asymptomatic carriers to life-threatening conditions, such as AIDS in HIV-2 infection or adult T-cell lymphoma/leukemia or tropical spastic paraparesis in HTLV-1 infection. HIV-2 is naturally resistant to some antiretrovirals frequently used to treat HIV-1 infection, but it does have effective antiretroviral therapy options. Unfortunately, HTLV still has limited therapeutic options. In this article, we will review the epidemiological, clinical, diagnostic, pathogenic and therapeutic aspects of infections caused by these human retroviruses.

Seroprevalence of Toxoplasma gondii IgG antibody in HIV/AIDS-infected individuals in Maputo, Mozambique

OBJECTIVE

To analyze the prevalence of IgG antibodies to Toxoplasma gondii in patients infected with HIV/AIDS and the association of demographic and social variables.

METHODS

Descriptive cross-sectional study that included the analysis of sociodemographic data and laboratory findings of 200 patients infected with HIV/AIDS treated in a laboratory unit in Maputo, Mozambique, in 2010. Individual data for all participants were collected with a self-administered questionnaire. Plasma samples were tested for IgG testing of anti- T. gondii using hemagglutination for the analysis of antibodies.

RESULTS

The seroprevalence of IgG anti- T. gondii was 46.0% (95%CI 39.2;52.9), 39.3% (95%CI 29.5;50.0) in men and 50.9% (95%CI 41.9;59.8) in women, with no difference between sex (OR 1.30; 95%CI 0.95;1.77; p = 0.12). Ages ranged from 10 to 60 years, with a higher prevalence of infection in older age groups, but with no significant difference between them. Regularly consuming cattle meat (OR 1.74; 95%CI 1.04;2.89, p = 0.05), breeding cats/dogs (OR 6.18; 95%CI 3.60;10.62, p < 0.000) and having regular contact with soil (OR 3.38; 95%CI 2.19;5.21; p < 0.000) were significantly associated with risk of latent infection.

CONCLUSIONS

Toxoplasmosis is an infection with high prevalence in Mozambique. Cultural and behavioral aspects increase the risk. Toxoplasmosis can be responsible in our environment by the great burden of morbidity and mortality associated with meningoencephalic injuries in patients with HIV/AIDS.

Profile of the HIV epidemic in Cape Verde: molecular epidemiology and drug resistance mutations among HIV-1 and HIV-2 infected patients from distinct islands of the archipelago

HIV-1 and HIV-2 have been detected in Cape Verde since 1987, but little is known regarding the genetic diversity of these viruses in this archipelago, located near the West African coast. In this study, we characterized the molecular epidemiology of HIV-1 and HIV-2 and described the occurrence of drug resistance mutations (DRM) among antiretroviral therapy naïve (ARTn) patients and patients under treatment (ARTexp) from different Cape Verde islands. Blood samples, socio-demographic and clinical-laboratory data were obtained from 221 HIV-positive individuals during 2010–2011. Phylogenetic and bootscan analyses of the pol region (1300 bp) were performed for viral subtyping. HIV-1 and HIV-2 DRM were evaluated for ARTn and ARTexp patients using the Stanford HIV Database and HIV-GRADE e.V. Algorithm Homepage, respectively. Among the 221 patients (169 [76.5%] HIV-1, 43 [19.5%] HIV-2 and 9 [4.1%] HIV-1/HIV-2 co-infections), 67% were female. The median ages were 34 (IQR = 1–75) and 47 (IQR = 12–84) for HIV-1 and HIV-2, respectively. HIV-1 infections were due to subtypes G (36.6%), CRF02_AG (30.6%), F1 (9.7%), URFs (10.4%), B (5.2%), CRF05_DF (3.0%), C (2.2%), CRF06_cpx (0.7%), CRF25_cpx (0.7%) and CRF49_cpx (0.7%), whereas all HIV-2 infections belonged to group A. Transmitted DRM (TDRM) was observed in 3.4% (2/58) of ARTn HIV-1-infected patients (1.7% NRTI, 1.7% NNRTI), but not among those with HIV-2. Among ARTexp patients, DRM was observed in 47.8% (33/69) of HIV-1 (37.7% NRTI, 37.7% NNRTI, 7.4% PI, 33.3% for two classes) and 17.6% (3/17) of HIV-2-infections (17.6% NRTI, 11.8% PI, 11.8% both). This study indicates that Cape Verde has a complex and unique HIV-1 molecular epidemiological scenario dominated by HIV-1 subtypes G, CRF02_AG and F1 and HIV-2 subtype A. The occurrence of TDRM and the relatively high level of DRM among treated patients are of concern. Continuous monitoring of patients on ART, including genotyping, are public policies to be implemented.

Performance of 3 rapid tests for discrimination between HIV-1 and HIV-2 in Guinea-Bissau, West Africa

As HIV-2 is intrinsically resistant to nonnucleoside reverse transcriptase inhibitors, it is mandatory to discriminate between HIV types before initiating antiretroviral treatment. Guinea-Bissau has the world's highest prevalence of HIV-2 and HIV-1/HIV-2 dually infected individuals. We evaluated 3 rapid tests for discrimination between HIV-1, HIV-2, and dual infections among 219 patients from Guinea-Bissau by comparing with the gold standard (INNO-LIA). Genie III HIV-1/HIV-2 was the best performer with regard to discriminatory capacity (agreement 91.8%), followed by Immunoflow HIV1-HIV2 (agreement 90.9%) and SD Bioline HIV-1/2 3.0 (agreement 84.5%). Our results underscore the need for evaluation of tests in relevant populations before implementation.