Background: Expanded access to HIV therapy in the developing world raises serious concerns regard... more Background: Expanded access to HIV therapy in the developing world raises serious concerns regarding the potential emergence and transmission of drug-resistant HIV strains. Although HIV drug resistance surveillance is recommended to track transmitted HIV drug resistance among newly infected individuals, the financial constraints in resource-limited countries prohibit such surveillance on a regular basis. The World Health Organization (WHO) recently introduced guidelines to address this issue. Methods: A survey was conducted in Ethiopia following the WHO guidelines to assess transmitted HIV drug resistance among recently HIV-infected individuals in Addis Ababa. Antiretroviral drug usage started 3 years earlier than commencement of the current expanded access to antiretroviral therapy in Ethiopia. Results: Of 75 eligible samples, 39 (52%) were successfully sequenced and genotyped in the protease and reverse transcriptase region, using both the ViroSeq® and TrueGene® genotyping systems, and analysed for drug resistance mutations using an algorithm from the Stanford HIV Reverse Transcriptase and Protease Database. The analysis revealed that transmitted HIV drug resistance in Addis Ababa is below the 5% threshold level for all three classes of antiretrovirals. Conclusions: The current first-line antiretroviral therapy strategy can be used with confidence in Ethiopia at this time; however, Ethiopia should conduct similar periodic surveys that include the capitals of Ethiopia's larger regional states to ensure early detection of any changes in the country's HIV drug resistance trend.
Both Leishmania and the human immunodeficiency virus (HIV) can infect and multiply in macrophages... more Both Leishmania and the human immunodeficiency virus (HIV) can infect and multiply in macrophages, and both can dysregulate the immune system. Recent studies indicate that Leishmania can induce the activation of HIV in latently infected monocytic and T cells. Moreover, HIV can enhance intracellular growth of Leishmania in macrophages. Here, Dawit Wolday and colleagues examine the mechanisms that might be involved in the immunopathogenesis of Leishmania- HIV co-infection.
Transactions of the Royal Society of Tropical Medicine and Hygiene, 1995
This communication reports 7 Ethiopian visceral leishmaniasis (VL) patients co-infected with huma... more This communication reports 7 Ethiopian visceral leishmaniasis (VL) patients co-infected with human immunodeficiency virus (HIV). The clinical and laboratory findings in 6 patients did not differ from classical VL. All patients had highly elevated anti-leishmanial antibody titres, determined by immunoglobulin G-based enzyme-linked immunosorbent assay; they most probably acquired the Leishmania infection before HIV. Amastigotes were identified in the splenic aspirates of 6 patients and in the lymph node aspirate of the 2 patients whose lymph nodes were examined. The CD4:CD8 lymphocyte ratio was depressed in those patients whose ratio was determined. Most patients showed some initial response to pentavalent antimonial therapy.
Transactions of the Royal Society of Tropical Medicine and Hygiene, 2006
The kinetics of potential surrogate markers in HIV-positive (HIV+) and HIV-negative (HIV-), smear... more The kinetics of potential surrogate markers in HIV-positive (HIV+) and HIV-negative (HIV-), smear-positive tuberculosis (Tb+) patients in Gondar, Ethiopia (n = 60) was investigated. Clinical symptoms, sputum conversion, sedimentation rate (SR), HIV viral load and serum levels of TNF-alpha were determined before and 8 weeks after treatment initiation. The co-infection rate of HIV was 45%. There were significantly higher initial levels of SR and TNF-alpha in HIV+/Tb+ patients (79 +/- 29 mm/h and 13.5 +/- 7.6 pg/ml), than in HIV-/Tb+ patients (60 +/- 23 mm/h and 6.8 +/- 5.9 pg/ml, P<0.001). In HIV-/Tb+ patients, there was a marked decrease in SR compared with co-infected patients (46% [33 +/- 24 mm/h at week 8] vs. 24% [61 +/- 27 mm/h at week 8]). The HIV viral load (4.99 [range 3.70-5.92] to 4.90 [range 3.96-5.78] log10 copies/ml from week 0 to 8) and TNF-alpha (13.5 +/- 7.6 to 12.0 +/- 6.0 pg/ml) remained high in HIV+/Tb+ patients. In Tb patients, SR was significantly increased in HIV+ compared with HIV- patients. Additionally, TNF-alpha and HIV viral load remained elevated in HIV+/Tb+ patients following treatment despite clinical improvement comparable to HIV-/Tb+ patients.
The present study monitored the changes in human immunodeficiency virus (HIV) viral load using a ... more The present study monitored the changes in human immunodeficiency virus (HIV) viral load using a reverse transcriptase (RT) assay and an HIV-1 RNA based assay, and relates these data to the dynamics of CD4 cell counts. The samples examined originate from a prospective study of HIV-1 subtype C infected, untreated Ethiopians followed twice yearly over a period of up to 5 years. The ExaVir Load test, version 1, was used for isolation and quantitation of HIV-1 RT in plasma. The RT activities recovered were compared to the HIV-1 RNA copy numbers, which had been determined previously by the NucliSens HIV-1 QT Test. There was a significant correlation between the data obtained in the two tests (r = 0.65, P < 0.0001). During follow-up, the median RT and RNA levels increased more or less in parallel up to approximately four times the values at admittance. CD4 cell counts, which had also been determined previously, decreased slowly but continuously from approximately 310 to 190 CD4 cells/ml. In the majority of individual patients, there was an inverse correlation between CD4 T-cell counts and RT activity, and with the RNA copy number, and the data obtained by either test could be used to predict CD4 T-cell counts. The ExaVir Load test thus provides data equivalent to the estimation of the number of HIV-1 RNA copies for the prediction of CD4 T-cell counts. It is based on a simple technique, can be run in any routine diagnostic laboratory, and is a competitive alternative for use in resource limited settings.
The herpes simplex virus type 2 (HSV-2) and human immunodeficiency virus (HIV) epidemics are beli... more The herpes simplex virus type 2 (HSV-2) and human immunodeficiency virus (HIV) epidemics are believed to fuel each other, especially in sub-Saharan countries. In Ethiopia during 1997-2002, a retrospective study was conducted to examine risk factors for infection and transmission of HSV-2, in a cohort of 1612 factory workers. Prevalence of HSV-2 seropositivity at enrollment was 40.9%, and incidence of seroconversion was 1.8 seroconversions/100 person-years (PY), which decreased over time. Independent risk factors for seropositivity were having an HSV-2-seropositive partner, female sex, HIV antibodies, positive Treponema pallidum particle agglutination assay result, older age, low education level, and orthodox religion. These same factors were independent risk factors for HSV-2 seroconversion, with the exception of the latter 3. Most HSV-2-infected persons did not report symptoms. Among 41 monogamous HSV-2-serodiscordant heterosexual couples, incidence of HSV-2 seroconversion was 20.75 seroconversions/100 PY for women and 4.93 seroconversions/100 PY for men. The high burden of both HSV-2 and HIV infection in Ethiopia warrants stringent control measures.
Background: Expanded access to HIV therapy in the developing world raises serious concerns regard... more Background: Expanded access to HIV therapy in the developing world raises serious concerns regarding the potential emergence and transmission of drug-resistant HIV strains. Although HIV drug resistance surveillance is recommended to track transmitted HIV drug resistance among newly infected individuals, the financial constraints in resource-limited countries prohibit such surveillance on a regular basis. The World Health Organization (WHO) recently introduced guidelines to address this issue. Methods: A survey was conducted in Ethiopia following the WHO guidelines to assess transmitted HIV drug resistance among recently HIV-infected individuals in Addis Ababa. Antiretroviral drug usage started 3 years earlier than commencement of the current expanded access to antiretroviral therapy in Ethiopia. Results: Of 75 eligible samples, 39 (52%) were successfully sequenced and genotyped in the protease and reverse transcriptase region, using both the ViroSeq® and TrueGene® genotyping systems, and analysed for drug resistance mutations using an algorithm from the Stanford HIV Reverse Transcriptase and Protease Database. The analysis revealed that transmitted HIV drug resistance in Addis Ababa is below the 5% threshold level for all three classes of antiretrovirals. Conclusions: The current first-line antiretroviral therapy strategy can be used with confidence in Ethiopia at this time; however, Ethiopia should conduct similar periodic surveys that include the capitals of Ethiopia's larger regional states to ensure early detection of any changes in the country's HIV drug resistance trend.
Both Leishmania and the human immunodeficiency virus (HIV) can infect and multiply in macrophages... more Both Leishmania and the human immunodeficiency virus (HIV) can infect and multiply in macrophages, and both can dysregulate the immune system. Recent studies indicate that Leishmania can induce the activation of HIV in latently infected monocytic and T cells. Moreover, HIV can enhance intracellular growth of Leishmania in macrophages. Here, Dawit Wolday and colleagues examine the mechanisms that might be involved in the immunopathogenesis of Leishmania- HIV co-infection.
Transactions of the Royal Society of Tropical Medicine and Hygiene, 1995
This communication reports 7 Ethiopian visceral leishmaniasis (VL) patients co-infected with huma... more This communication reports 7 Ethiopian visceral leishmaniasis (VL) patients co-infected with human immunodeficiency virus (HIV). The clinical and laboratory findings in 6 patients did not differ from classical VL. All patients had highly elevated anti-leishmanial antibody titres, determined by immunoglobulin G-based enzyme-linked immunosorbent assay; they most probably acquired the Leishmania infection before HIV. Amastigotes were identified in the splenic aspirates of 6 patients and in the lymph node aspirate of the 2 patients whose lymph nodes were examined. The CD4:CD8 lymphocyte ratio was depressed in those patients whose ratio was determined. Most patients showed some initial response to pentavalent antimonial therapy.
Transactions of the Royal Society of Tropical Medicine and Hygiene, 2006
The kinetics of potential surrogate markers in HIV-positive (HIV+) and HIV-negative (HIV-), smear... more The kinetics of potential surrogate markers in HIV-positive (HIV+) and HIV-negative (HIV-), smear-positive tuberculosis (Tb+) patients in Gondar, Ethiopia (n = 60) was investigated. Clinical symptoms, sputum conversion, sedimentation rate (SR), HIV viral load and serum levels of TNF-alpha were determined before and 8 weeks after treatment initiation. The co-infection rate of HIV was 45%. There were significantly higher initial levels of SR and TNF-alpha in HIV+/Tb+ patients (79 +/- 29 mm/h and 13.5 +/- 7.6 pg/ml), than in HIV-/Tb+ patients (60 +/- 23 mm/h and 6.8 +/- 5.9 pg/ml, P<0.001). In HIV-/Tb+ patients, there was a marked decrease in SR compared with co-infected patients (46% [33 +/- 24 mm/h at week 8] vs. 24% [61 +/- 27 mm/h at week 8]). The HIV viral load (4.99 [range 3.70-5.92] to 4.90 [range 3.96-5.78] log10 copies/ml from week 0 to 8) and TNF-alpha (13.5 +/- 7.6 to 12.0 +/- 6.0 pg/ml) remained high in HIV+/Tb+ patients. In Tb patients, SR was significantly increased in HIV+ compared with HIV- patients. Additionally, TNF-alpha and HIV viral load remained elevated in HIV+/Tb+ patients following treatment despite clinical improvement comparable to HIV-/Tb+ patients.
The present study monitored the changes in human immunodeficiency virus (HIV) viral load using a ... more The present study monitored the changes in human immunodeficiency virus (HIV) viral load using a reverse transcriptase (RT) assay and an HIV-1 RNA based assay, and relates these data to the dynamics of CD4 cell counts. The samples examined originate from a prospective study of HIV-1 subtype C infected, untreated Ethiopians followed twice yearly over a period of up to 5 years. The ExaVir Load test, version 1, was used for isolation and quantitation of HIV-1 RT in plasma. The RT activities recovered were compared to the HIV-1 RNA copy numbers, which had been determined previously by the NucliSens HIV-1 QT Test. There was a significant correlation between the data obtained in the two tests (r = 0.65, P < 0.0001). During follow-up, the median RT and RNA levels increased more or less in parallel up to approximately four times the values at admittance. CD4 cell counts, which had also been determined previously, decreased slowly but continuously from approximately 310 to 190 CD4 cells/ml. In the majority of individual patients, there was an inverse correlation between CD4 T-cell counts and RT activity, and with the RNA copy number, and the data obtained by either test could be used to predict CD4 T-cell counts. The ExaVir Load test thus provides data equivalent to the estimation of the number of HIV-1 RNA copies for the prediction of CD4 T-cell counts. It is based on a simple technique, can be run in any routine diagnostic laboratory, and is a competitive alternative for use in resource limited settings.
The herpes simplex virus type 2 (HSV-2) and human immunodeficiency virus (HIV) epidemics are beli... more The herpes simplex virus type 2 (HSV-2) and human immunodeficiency virus (HIV) epidemics are believed to fuel each other, especially in sub-Saharan countries. In Ethiopia during 1997-2002, a retrospective study was conducted to examine risk factors for infection and transmission of HSV-2, in a cohort of 1612 factory workers. Prevalence of HSV-2 seropositivity at enrollment was 40.9%, and incidence of seroconversion was 1.8 seroconversions/100 person-years (PY), which decreased over time. Independent risk factors for seropositivity were having an HSV-2-seropositive partner, female sex, HIV antibodies, positive Treponema pallidum particle agglutination assay result, older age, low education level, and orthodox religion. These same factors were independent risk factors for HSV-2 seroconversion, with the exception of the latter 3. Most HSV-2-infected persons did not report symptoms. Among 41 monogamous HSV-2-serodiscordant heterosexual couples, incidence of HSV-2 seroconversion was 20.75 seroconversions/100 PY for women and 4.93 seroconversions/100 PY for men. The high burden of both HSV-2 and HIV infection in Ethiopia warrants stringent control measures.
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