Brief Report: Self-Reported HIV-Positive Status but Subsequent HIV-Negative Test Results in Population-Based HIV Impact Assessment Survey Participants-11 Sub-Saharan African Countries, 2015-2018

BACKGROUND

HIV testing is a critical step to accessing antiretroviral therapy (ART) because early diagnosis can facilitate earlier initiation of ART. This study presents aggregated data of individuals who self-reported being HIV-positive but subsequently tested HIV-negative during nationally representative Population-Based HIV Impact Assessment surveys conducted in 11 countries from 2015 to 2018.

METHOD

Survey participants aged 15 years or older were interviewed by trained personnel using a standard questionnaire to determine HIV testing history and self-reported HIV status. Home-based HIV testing and counseling using rapid diagnostic tests with return of results were performed by survey staff according to the respective national HIV testing services algorithms on venous blood samples. Laboratory-based confirmatory HIV testing for all participants identified as HIV-positives and self-reported positives, irrespective of HIV testing results, was conducted and included Geenius HIV-1/2 and DNA polymerase chain reaction if Geenius was negative or indeterminate.

RESULTS

Of the 16,630 participants who self-reported as HIV-positive, 16,432 (98.6%) were confirmed as HIV-positive and 198 (1.4%) were HIV-negative by subsequent laboratory-based testing. Participants who self-reported as HIV-positive but tested HIV-negative were significantly younger than 30 years, less likely to have received ART, and less likely to have received a CD4 test compared with participants who self-reported as HIV-positive with laboratory-confirmed infection.

CONCLUSIONS

A small proportion of self-reported HIV-positive individuals could not be confirmed as positive, which could be due to initial misdiagnosis, deliberate wrong self-report, or misunderstanding of the questionnaire. As universal ART access is expanding, it is increasingly important to ensure quality of HIV testing and confirmation of HIV diagnosis before ART initiation.

Rapid antiretroviral therapy initiation in patients with advanced HIV disease: 6-month outcomes of an observational cohort evaluation in Lesotho

For adults and adolescents, the World Health Organization defines advanced HIV disease (AHD) as a CD4 (cluster of differentiation 4) count of <200 cells/mm3 or a clinical stage 3 or 4 event. We describe clinical outcomes in a cohort of AHD patients at two regional hospitals in Lesotho. From November 2018-June 2019, we prospectively enrolled eligible patients (≥15 years) not on antiretroviral therapy (ART) presenting with WHO-defined AHD into a differentiated model of care for AHD (including rapid ART initiation) and followed them for six months. All patients received Tuberculosis (TB) symptom screening with further diagnostic testing; serum cryptococcal antigen (CrAg) screening was done for CD4 <100 cells/mm3 or WHO clinical stage 3 or 4. Medical record data were abstracted using visit checklist forms. Categorical and continuous variables were summarized using frequencies, percentages, and means, respectively. Kaplan-Meier was used to estimate survival. Of 537 HIV-positive patients screened, 150 (27.9%) had AHD of which 109 were enrolled. Mean age was 38 years and 62 (56.9%) were men. At initial clinic visit, 8 (7.3%) were already on treatment and 33% (36/109) had presumptive TB per symptom screening. Among 39/109 (40.2%) patients screened for CrAg at initial visit, five (12.8%) were CrAg-positive. Among 109 enrolled, 77 (70.6%) initiated ART at their initial clinic visit, while 32 delayed ART initiation (median delay: 14 days). Of the 109 participants enrolled, 76 (69.7%) completed the 6-month follow-up, 17 (15.6%) were lost to follow-up, 5 (4.6%) transferred to other health facilities and 11 (10.1%) died. The 6-month survival was 87.4%; among 74 patients with a viral load result, 6-month viral suppression (<1,000 copies/ml) was 85.1%. Our study found that even after the implementation of Test and Treat of ART in 2016 in Lesotho, over 25% of patients screened had AHD. Patients with AHD had a high prevalence of TB and CrAg positivity, underscoring the need to assess for AHD and rapidly initiate ART within a package of AHD care for optimal patient outcomes.

The epidemiology of HIV population viral load in twelve sub-Saharan African countries

BACKGROUND

We examined the epidemiology and transmission potential of HIV population viral load (VL) in 12 sub-Saharan African countries.

METHODS

We analyzed data from Population-based HIV Impact Assessments (PHIAs), large national household-based surveys conducted between 2015 and 2019 in Cameroon, Cote d'Ivoire, Eswatini, Kenya, Lesotho, Malawi, Namibia, Rwanda, Tanzania, Uganda, Zambia, and Zimbabwe. Blood-based biomarkers included HIV serology, recency of HIV infection, and VL. We estimated the number of people living with HIV (PLHIV) with suppressed viral load (<1,000 HIV-1 RNA copies/mL) and with unsuppressed viral load (viremic), the prevalence of unsuppressed HIV (population viremia), sex-specific HIV transmission ratios (number female incident HIV-1 infections/number unsuppressed male PLHIV per 100 persons-years [PY] and vice versa) and examined correlations between a variety of VL metrics and incident HIV. Country sample sizes ranged from 10,016 (Eswatini) to 30,637 (Rwanda); estimates were weighted and restricted to participants 15 years and older.

RESULTS

The proportion of female PLHIV with viral suppression was higher than that among males in all countries, however, the number of unsuppressed females outnumbered that of unsuppressed males in all countries due to higher overall female HIV prevalence, with ratios ranging from 1.08 to 2.10 (median: 1.43). The spatial distribution of HIV seroprevalence, viremia prevalence, and number of unsuppressed adults often differed substantially within the same countries. The 1% and 5% of PLHIV with the highest VL on average accounted for 34% and 66%, respectively, of countries' total VL. HIV transmission ratios varied widely across countries and were higher for male-to-female (range: 2.3-28.3/100 PY) than for female-to-male transmission (range: 1.5-10.6/100 PY). In all countries mean log10 VL among unsuppressed males was higher than that among females. Correlations between VL measures and incident HIV varied, were weaker for VL metrics among females compared to males and were strongest for the number of unsuppressed PLHIV per 100 HIV-negative adults (R2 = 0.92).

CONCLUSIONS

Despite higher proportions of viral suppression, female unsuppressed PLHIV outnumbered males in all countries examined. Unsuppressed male PLHIV have consistently higher VL and a higher risk of transmitting HIV than females. Just 5% of PLHIV account for almost two-thirds of countries' total VL. Population-level VL metrics help monitor the epidemic and highlight key programmatic gaps in these African countries.

Contribution of PEPFAR-Supported HIV and TB Molecular Diagnostic Networks to COVID-19 Testing Preparedness in 16 Countries

The US President's Emergency Plan for AIDS Relief (PEPFAR) supports molecular HIV and tuberculosis diagnostic networks and information management systems in low- and middle-income countries. We describe how national programs leveraged these PEPFAR-supported laboratory resources for SARS-CoV-2 testing during the COVID-19 pandemic. We sent a spreadsheet template consisting of 46 indicators for assessing the use of PEPFAR-supported diagnostic networks for COVID-19 pandemic response activities during April 1, 2020, to March 31, 2021, to 27 PEPFAR-supported countries or regions. A total of 109 PEPFAR-supported centralized HIV viral load and early infant diagnosis laboratories and 138 decentralized HIV and TB sites reported performing SARS-CoV-2 testing in 16 countries. Together, these sites contributed to >3.4 million SARS-CoV-2 tests during the 1-year period. Our findings illustrate that PEPFAR-supported diagnostic networks provided a wide range of resources to respond to emergency COVID-19 diagnostic testing in 16 low- and middle-income countries.

HIV-1 Recent Infection Testing Algorithm With Antiretroviral Drug Detection to Improve Accuracy of Incidence Estimates

BACKGROUND

HIV-1 incidence calculation currently includes recency classification by HIV-1 incidence assay and unsuppressed viral load (VL ≥ 1000 copies/mL) in a recent infection testing algorithm (RITA). However, persons with recent classification not virally suppressed and taking antiretroviral (ARV) medication may be misclassified.

SETTING

We used data from 13 African household surveys to describe the impact of an ARV-adjusted RITA on HIV-1 incidence estimates.

METHODS

HIV-seropositive samples were tested for recency using the HIV-1 Limiting Antigen (LAg)-Avidity enzyme immunoassay, HIV-1 viral load, ARVs used in each country, and ARV drug resistance. LAg-recent result was defined as normalized optical density values ≤1.5. We compared HIV-1 incidence estimates using 2 RITA: RITA1: LAg-recent + VL ≥ 1000 copies/mL and RITA2: RITA1 + undetectable ARV. We explored RITA2 with self-reported ARV use and with clinical history.

RESULTS

Overall, 357 adult HIV-positive participants were classified as having recent infection with RITA1. RITA2 reclassified 55 (15.4%) persons with detectable ARV as having long-term infection. Those with detectable ARV were significantly more likely to be aware of their HIV-positive status (84% vs. 10%) and had higher levels of drug resistance (74% vs. 26%) than those without detectable ARV. RITA2 incidence was lower than RITA1 incidence (range, 0%-30% decrease), resulting in decreased estimated new infections from 390,000 to 341,000 across the 13 countries. Incidence estimates were similar using detectable or self-reported ARV (R2 > 0.995).

CONCLUSIONS

Including ARV in RITA2 improved the accuracy of HIV-1 incidence estimates by removing participants with likely long-term HIV infection.

FRI0064 SAFETY OF LOW DOSE METHOTREXATE (MTX) AND TUBERCULOSIS (TB)

Background:

Increased awareness of the importance of MTX in rheumatic disease is leading to more MTX use in patients from TB-endemic areas. Current management guidelines for rheumatic disease address TB in the context of biologics but not MTX use.

Objectives:

To systematically review the published literature on TB rates with MTX ≤30 mg per week.

Methods:

We searched CINAHL, Embase, Global, MEDLINE and World of Science databases (Jan 1990 to May 2018) for terms including ‘methotrexate’ and ‘tuberculosis’. We also searched citations from review articles. Titles, abstracts or full manuscripts of the 4707 reports identified were screened independently by 2 reviewers to identify studies reporting TB in patients taking MTX. Study quality was assessed using the McGill Mixed Methods Appraisal Tool (MMAT). Data was extracted on TB incidence (new TB diagnosis vs reactivation of latent TB), and outcomes (pulmonary, dissemination, death) and safety of isoniazid, INH. Descriptive summaries are presented on studies providing outcomes in patients taking MTX ≤30 mg per week.

Results:

After removing duplicates and studies not meeting criteria or providing sufficient information, 31 studies were included (8 cohort, 7 case-control, 1 clinical trial, 15 case reports/case series). Only 27% of articles reported data from low to moderate human development index countries. Studies were of moderate quality. Seven case control studies were heterogeneous but most demonstrated a modest increased risk of TB with MTX (Table). Five cohort studies reported TB incidence rates in rheumatic disease (treated with MTX +/- biologics) ranging from 102-367.9/100,000 patient-years. These rates were generally higher than comparator general population rates. Two cohort studies of MTX in RA (without biologic) reported cumulative TB incidence in Maldova (12 TB cases in 44 RA patients, 27%) and in China (9/114, 7.9%). Other cohort studies generated rates of overt infection (143/100,000 patient years in Spain, higher if co-prescribed with corticosteroids and other immunosuppressants in South Africa), and latent TB rates detection (16/922 RA screened, 1.7%, in Canada). When reported, rates of extra-pulmonary TB were higher than comparator general population rates. One clinical trial (China), 2 cohorts (Japan, USA) and 2 case-series (Belgium, USA) evaluated safety of INH and MTX. Isoniazid-related hepatotoxicity and neutropenia were generally more common when taken with MTX, but were usually reversible.

Conclusion:

Despite a paucity of high-quality data, this review confirms that TB screening and clinical surveillance are needed in patients from TB-endemic areas who are prescribed MTX, particularly with co-administration of corticosteroids or other immunosuppressants. Isoniazid, if monitored, appears safe and prevents TB reactivation.

References:

Table .

Case control studies

Region (Year)DiagnosisTB with MTXTB without MTXOdds RatioMexico(1999)Mixed (4 RA)1/65/752.76Japan(2004)RA3/4717/1540.56Canada(2009)RA29/48321/10463.12Brazil(2010)Lupus2/31/57112Taiwan(2012)Psoriasis33/144464/23411.2Taiwan(2015)JIA4/3574/10262.90South Africa (2017)RA0/1340/18NA

JIA=juvenile idiopathic arthritis

Acknowledgments:

Funded by the International League Against Rheumatism and McGill University Global Health Scholar Awards

Disclosure of Interests:

Anna Davidson: None declared, Alize Gunay: None declared, Ines Colmegna: None declared, Diane Lacaille: None declared, Hal Loewen: None declared, Michele Meltzer: None declared, Rosie Scuccimarri: None declared, Yewondwossen Mengistu: None declared, Sasha Bernatsky: None declared, Carol Hitchon Grant/research support from: UCB Canada; Pfizer Canada

SAT0078 SAFETY OF LOW DOSE METHOTREXATE (MTX) IN HUMAN IMMUNODEFICIENCY VIRUS (HIV) INFECTION

Background:

Increased awareness of the efficacy of MTX in rheumatic disease is leading to more MTX use in patients from HIV endemic areas. While HIV related immunosuppression may contribute to improvement of some rheumatic diseases, immune reconstitution from highly active antiretroviral therapy (HAART) may lead to exacerbation or presentation of autoimmune disorders for which MTX therapy may be warranted. Most management guidelines for rheumatic disease do not address MTX use in the context of HIV.

Objectives:

To systematically review the published literature on the safety of using MTX ≤30 mg per week in HIV.

Methods:

We searched CINAHL, Embase, Global, MEDLINE and World of Science databases (Jan 1990 to May 2018) for terms including ‘methotrexate’ and ‘human immunodeficiency virus’. We also searched citations from review articles. Titles, abstracts or full manuscripts were screened independently by 2 reviewers to identify studies reporting HIV in patients taking MTX. Study quality was assessed using the McGill Mixed Methods Appraisal Tool (MMAT). Data was extracted on MTX and HIV adverse events (MTX toxicity, HIV viral load, CD4 count). Descriptive summaries are presented for studies providing outcomes in patients taking MTX ≤30 mg per week.

Results:

After removing duplicates and studies not meeting criteria or not providing sufficient information, 42 of the 2714 identified reports were included (1 clinical trial, 2 cohort, 1 cross-sectional study, 38 case reports/case series). Most reports (81%) originated from USA or Europe. Study quality was generally good with most studies fulfilling 50-100% of MMAT criteria. The randomized controlled trial (USA) assessing MTX on atherosclerotic disease in HIV showed that adverse events were more common in MTX versus placebo (12.8% vs 5.6%, p non-inferiority <0.05) and included infection, transient CD4 and CD8 drop, pulmonary toxicity, and death (1 attributed to MTX/HIV, 1 unrelated). One cohort study (South Africa) reported 43 RA patients on MTX who acquired HIV. In this cohort, RA generally improved despite only 5 individuals continuing MTX. No data on MTX adverse event rates was reported. One cohort study (USA) reported 13 HIV patients with myositis. One received MTX (with other immunosuppression) without MTX adverse effects but died due to AIDS. A cross-sectional study (France) of 43 HIV pts with autoimmune disease reported one patient on MTX (and other immunosuppression) developed an adverse event (cytopenia) compared to 5/33 patients not on MTX (cytopenia). The 38 case reports/series described 54 individuals with HIV receiving MTX. Of these studies, 27 (describing 42 subjects) reported on MTX adverse events and 35 (describing 46 subjects) reported on HIV adverse events. MTX adverse events developed in 29 subjects (hematologic 13, renal/hepatic 1, opportunistic infections 10, other events 2). HIV adverse events were noted in 23 subjects (Kaposi’s sarcoma 4, CD4 decrease 16, HIV viral titer increase 4). Five deaths were reported (2 infection, 1 infection and wasting, 2 HIV related deaths). Most subjects also received corticosteroids or other immunosuppressants including biologics.

Conclusion:

There remains limited data on the safety of low dose MTX in HIV. Surveillance for HIV is warranted for individuals on MTX who are at risk for acquiring HIV. Caution and careful monitoring for MTX toxicity, opportunistic infections and HIV state is suggested if MTX is used in the setting of HIV particularly if combined with other immunosuppression.

References:

[1] Clin Infectious Disease 2019:68

[2] J Rheumatology 2014:41

[3] Arthritis and Rheumatism 2003:49

[4] Medicine 2017:96

Acknowledgments :

Funding from International League Against Rheumatism

McGill University Global Health Scholar Awards

Disclosure of Interests:

Alize Gunay: None declared, Anna Davidson: None declared, Ines Colmegna: None declared, Diane Lacaille: None declared, Hal Loewen: None declared, Michele Meltzer: None declared, Yewondwossen Mengistu: None declared, Rosie Scuccimarri: None declared, Zenebe Yirsaw: None declared, Sasha Bernatsky: None declared, Carol Hitchon Grant/research support from: UCB Canada; Pfizer Canada

Field expansion of DNA polymerase chain reaction for early infant diagnosis of HIV-1: The Ethiopian experience

Background

Early diagnosis of infants infected with HIV (EID) and early initiation of treatment significantly reduces the rate of disease progression and mortality. One of the challenges to identification of HIV-1-infected infants is availability and/or access to quality molecular laboratory facilities which perform molecular virologic assays suitable for accurate identification of the HIV status of infants.

Method

We conducted a joint site assessment and designed laboratories for the expansion of DNA polymerase chain reaction (PCR) testing based on dried blood spot (DBS) for EID in six regions of Ethiopia. Training of appropriate laboratory technologists and development of required documentation including standard operating procedures (SOPs) was carried out. The impact of the expansion of EID laboratories was assessed by the number of tests performed as well as the turn-around time.

Results

DNA PCR for EID was introduced in 2008 in six regions. From April 2006 to April 2008, a total of 2848 infants had been tested centrally at the Ethiopian Health and Nutrition Research Institute (EHNRI) in Addis Ababa, and which was then the only laboratory with the capability to perform EID; 546 (19.2%) of the samples were positive. By November 2010, EHNRI and the six laboratories had tested an additional 16 985 HIV-exposed infants, of which 1915 (11.3%) were positive. The median turn-around time for test results was 14 days (range 14–21 days).

Conclusion

Expansion of HIV DNA PCR testing facilities that can provide quality and reliable results is feasible in resource-limited settings. Regular supervision and monitoring for quality assurance of these laboratories is essential to maintain accuracy of testing.

Slower clearance of nevirapine resistant virus in infants failing extended nevirapine prophylaxis for prevention of mother-to-child HIV transmission

Nevirapine resistance mutations arise commonly following single or extended-dose nevirapine (ED-NVP) prophylaxis to prevent mother-to-child transmission (PMTCT) of human immunodeficiency virus (HIV), but decay within 6-12 months of single-dose exposure. Use of ED-NVP prophylaxis in infants is expected to rise, but data on decay of nevirapine resistance mutations in infants in whom ED-NVP failed remain limited. We assessed, in Ethiopian infants participating in the Six-Week Extended Nevirapine (SWEN) Trial, the prevalence and persistence of nevirapine resistance mutations at 6 and 12 months following single-dose or up to 6 weeks of ED-NVP, and correlated their presence with the timing of infection and the type of resistance mutations. Standard population genotyping followed by high-throughput cloning were done on dried blood spot samples collected during the trial. More infants who received ED-NVP had nevirapine resistance detected by standard population genotyping (high frequencies) at age 6 months compared with those who received single-dose nevirapine (SD-NVP) (58% of 24 vs. 26% of 19, respectively; p = 0.06). Moreover, 56% of ED-NVP-exposed infants with nevirapine resistance at age 6 months still had nevirapine resistance mutations present at high frequencies at age 1 year. Infants infected before 6 weeks of age who received either SD- or ED-NVP were more likely to have Y181C or K103N; these mutations were also more likely to persist at high frequencies through 1 year of age. HIV-infected infants in whom ED-NVP prophylaxis fails are likely to experience delayed clearance of nevirapine-resistant virus in the first year of life, which in turn places them at risk for early selection of multidrug-resistant HIV after initial therapy with nonnucleoside reverse transcriptase inhibitor-based regimens.

Timing of blood sampling for CD4 T-cell counting influences HAART decisions

BACKGROUND

Variability in CD4 T-cell counts has been described for both healthy and HIV-infected persons. It may influence decisions with respect to initiation and monitoring of antiretroviral treatment.

OBJECTIVE

to measure the effect of timing of blood sampling for blood cell count measurement.

METHOD

The study population consisted of 71 Ethiopian patients in an observational cohort, either being monitored prior to HAART (n = 40) or receiving HAART (n = 31) at an ART Clinic in Addis Ababa.

RESULT

The median CD4 count demonstrated significantly increasing trends from the morning (8 am) to the afternoon (4 pm), both for patients on HAART (increase of 137 CD4 cell/microl; p = 0.003) and for patients initiating HAART (increase of 56 CD4 cells/microl; p = 0.038). This trend was also observed for CD8+ and CD3+ T-lymphocytes, (initiating HAART p = 0.002 and p = 0.001; patients on HAART p = 0.015 and p = 0.004, respectively).

CONCLUSION

The implications of these findings are for the decision to start HAART or the decision to start prevention of opportunistic infections in Ethiopian patients on HAART.

Multidrug resistant Salmonella Concord is a major cause of salmonellosis in children in Ethiopia

INTRODUCTION

S. Concord in Ethiopia. The objective of this study was to determine the aetiology of febrile and diarrhoeic illness in Ethiopian children focussing on Salmonella.

METHODOLOGY

Paediatric patients (n = 1,225) presenting with diarrhoea or fever from the paediatric outpatient department of Tikur Anbessa University Hospital, Addis Ababa (n = 825), and Jimma University Hospital, South West Ethiopia (n = 400), were investigated for pathogens from January to August 2006.

RESULTS

Parasites were detected in 337 cases, Salmonella in 65, and Shigella in 61. Serotyping of Salmonella (including 48 stored isolates) demonstrated the dominance of S. Concord:  S. Concord (85), S. Typhimurium (7), S. Paratyphi B (2), S. Haifa (1), S. Typhi (2),  S. Enteritidis (4), S. Butantan (2), S. Infantis (1), S. Pomona (1), Salmonella group M (28:y:-)  (1), and S. Oskarshamn (1). Six isolates in serogroups B and D were untypeable. Of 81 S. Concord isolates, 30% were invasive, most (86.5%) were positive for ESBL production by E-test and 70% were multiply resistant to trimethoprim-sulphamethaxole, ceftriaxone, chloramphenicol and gentamicin, of which over one quarter (27%) also showed reduced susceptibility to ciprofloxacin.

CONCLUSION

Multi-drug resistant S. Concord was the major cause of salmonellosis in two regions of Ethiopia. The strain isolated was highly invasive, highly antibiotic-resistant, and represents a threat to heath care globally.

Differences in HIV type 1 RNA plasma load profile of closely related cocirculating Ethiopian subtype C strains: C and C'

Two HIV-1 subtype C subclusters have been identified in Ethiopia (C and C') with little knowledge regarding their biological or clinical differences. We longitudinally monitored HIV-1 viral loads and CD4(+) T cell counts for 130 subtype C-infected individuals from Ethiopia over 5 years. The genetic subclusters C and C' were determined and comparisons were made between the groups. None of the study individuals received antiretroviral therapy. Subcluster C' was found to be the more prevalent (72.3%) genotype circulating. Individuals infected with subcluster C' harbored higher viral loads in comparison to subcluster C-infected individuals when the CD4(+) T cell counts were high (500-900 cells/mm(3)), whereas at low CD4(+) T cell counts (0-150 cells/mm(3)) individuals infected with subcluster C viruses showed higher viral loads. We identified a greater number of deaths among individuals infected with subcluster C viruses in comparison to C'. Our results indicate that infection with subcluster C viruses leads to a more rapid onset of disease, despite the initial lower HIV-1 RNA plasma loads. Additionally, the higher viral loads seen for HIV-1 subcluster C' infections at higher CD4(+) T cell counts can help explain the higher prevalence of this subtype in Ethiopia.

Typhoid fever in Ethiopia

This review focuses on the reports of salmonellosis by investigators in different parts of Ethiopia, in particular focusing on the levels of typhoid fever. Many of the reports are published in local journals that are not available online. There have been seven studies which diagnosed typhoid fever by laboratory culture and there is no coordinated epidemiological surveillance. All conducted research and reports from different health institutions in Ethiopia indicate that typhoid fever was still a common problem up to the most recent study in 2000 and that the extensive use of first-line drugs has led to the development of multiple drug resistance. In the sites covered by this review, the total number of published cases of typhoid fever dropped over time reflecting the decline in research capacity in the country. Data on the proportion of patients infected by different serovars of Salmonella suggest that the non-Typhi serovars of Salmonella are increasing. The published evidence suggests that typhoid fever is a current public health problem in Ethiopia although population based surveys, based on good microbiological diagnosis, are urgently needed. Only then can the true burden of enteric fever be estimated and the benefit of public health control measures, such as health education, safe water provision, improved food hygienic practices and eventually vaccination, be properly assessed.

Extended-dose nevirapine to 6 weeks of age for infants to prevent HIV transmission via breastfeeding in Ethiopia, India, and Uganda: an analysis of three randomised controlled trials

BACKGROUND

UNICEF/WHO recommends that infants born to HIV-infected mothers who do not have access to acceptable, feasible, affordable, sustainable, and safe replacement feeding should be exclusively breastfed for at least 6 months. The aim of three trials in Ethiopia, India, and Uganda was to assess whether daily nevirapine given to breastfed infants through 6 weeks of age can decrease HIV transmission via breastfeeding.

METHODS

HIV-infected women breastfeeding their infants were eligible for participation. Participants were randomly assigned to receive either single-dose nevirapine (nevirapine 200 mg to women in labour and nevirapine 2 mg/kg to newborns after birth) or 6 week extended-dose nevirapine (nevirapine 200 mg to women in labour and nevirapine 2 mg/kg to newborn babies after birth plus nevirapine 5 mg daily from days 8-42 for the infant). The randomisation sequences were generated by computer at a central data coordinating centre. The primary endpoint was HIV infection at 6 months of age in infants who were HIV PCR negative at birth. Analyses were by modified intention to treat, excluding infants with missing specimens and those with indeterminate or confirmed HIV infection at birth. These studies are registered with ClinicalTrials.gov, numbers NCT00074399, NCT00061321, and NCT00639938.

FINDINGS

2024 liveborn infants randomised in the study had at least one specimen tested before 6 months of age (1047 infants in the single-dose group and 977 infants in the extended-dose group). The modified intention-to-treat population included 986 infants in the single-dose group and 901 in the extended-dose group. At 6 months, 87 children in the single-dose group and 62 in the extended-dose group were infected with HIV (relative risk 0.80, 95% CI 0.58-1.10; p=0.16). At 6 weeks of age, 54 children in the single-dose group and 25 in the extended-dose group were HIV positive (0.54, 0.34-0.85; p=0.009). 393 infants in the single-dose group and 346 in the extended-dose group experienced grade 3 or 4 serious adverse events during the study (p=0.54).

INTERPRETATION

Although a 6-week regimen of daily nevirapine might be associated with a reduction in the risk of HIV transmission at 6 weeks of age, the lack of a significant reduction in the primary endpoint-risk of HIV transmission at 6 months-suggests that a longer course of daily infant nevirapine to prevent HIV transmission via breast milk might be more effective where access to affordable and safe replacement feeding is not yet available and where the risks of replacement feeding are high.

FUNDING

US National Institutes of Health; US National Institute of Allergy and Infectious Diseases; Fogarty International Center.

Threshold survey evaluating transmitted HIV drug resistance among public antenatal clinic clients in Addis Ababa, Ethiopia

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.

Threshold survey evaluating transmitted HIV drug resistance among public antenatal clinic clients in Addis Ababa, Ethiopia

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.

Assessment of the implementation of HIV-rapid test kits at different levels of health institutions in Ethiopia

OBJECTIVE

Evaluation and monitoring of Human Immunodeficiency Virus (HIV) testing reagents at the point of service is helpful to prevent the occurrence of problems related to testing and interpretation. To evaluate the implementation of HIV rapid test kits at the point of services in voluntarily counseling and testing (VCT) and diagnostic centers in Ethiopia.

METHODS

The assessment was the third phase of evaluation of HIV rapid test kits in Ethiopia followed from phase-I and phase-II. Known proficiency testing panels, well-structured questionnaire (addressing type of tests, human resource and problems related to tests), onsite supervision and retesting of samples collected from sites were used to evaluate the performances of reagents and laboratories.

RESULTS

Forty-four health institutions were included. Thirty-six (90.0%) health institutions had trained human resource on HIV testing. In 27 (61.4%) three types of HIV rapid test kits (Determine, Capillus and Unigold) were available. Serial-algorithm was used in all the laboratories. In 31 (70.4%) of them external quality control specimens were not used. Twenty two (50.0%) of the laboratories reported frequent shortage of reagents. All (100%) were able to identify negative specimens distributed. Positive proficiency panel samples were identified in 37 (94.8%) of the 39 laboratories. There was 98.3% agreement at a screening level between the sites and the central laboratory. Rate of discrepancy between screening and confirmatory assays was found to be 3.0% and 2.1% at the sites and at central laboratory, respectively.

CONCLUSION

The test kits showed a good performance at the point of services in the field sites. However, continuous assessment of HIV test kits at the point of service and training of professionals on newly arrived techniques are recommended to have effective testing performance with acceptable sensitive and specific testing algorithm. Effective quality assurance program should be in place to support programs such as VCT, prevention of mother-to-child-transmission and antiretroviral therapy.

Diabetic infections: clinical and bacteriological study at Tikur Anbessa Specialized University Hospital, Addis Ababa, Ethiopia

INTRODUCTION

Infection is the most serious complication of diabetes and recognized as causing significant morbidity and mortality.

OBJECTIVES

To assess the prevalence and pattern of infection, determine the causative organisms.

METHODS

A cross sectional study involved 179 diabetic patients admitted to the Department of Internal Medicine of Tikur Anbessa Specialized University Hospital performed between Nov. 2000 - Nov 2002, clinical data were documented, a total of 114 clinical specimens (40 pus, 23 blood and 51 urine) were submitted to bacteriology laboratory for bacterial isolation and identification.

RESULTS

The mean +/- SD fasting blood sugar was 246.0 +/- 153.3 mg/dl. Fifty eight (32.4%) of patients were admitted in state of diabetic ketoacidosis. The prevalence of infection in diabetic patients was 44%. Diabetic foot infection (35%) was the commonest, followed by pulmonary tuberculosis 22%, urinary tract infection (14%), pneumonia (12.8%), skin and subcutaneous infection (12.8%). About 30% of bacterial isolates were Staphylococcus aureus followed by Klebsiella pnumeniae (23.4%), Escherichia coli (19%) and Pseduomonas spp (15%). The rest of the isolates were less frequent and ranged between 2 to 6.4%. More than one bacterial species were also isolated from 10% of the positive cultures. Main causes of deaths in hospitalized diabetic patients were cardiovascular diseases (6/15), end stage renal disease (3/15) and sepsis (2/15).

CONCLUSION

Infections were the leading cause of morbidity while cardiovascular diseases were the leading cause of mortality. Diabetic foot ulcers were the major cause of infection followed by tuberculosis, skin and subcutaneous infections and pneumonia. The prevalence of tuberculosis in diabetic patient is increasing; S. aureus from wound infection and E. colifrom urinary tract infection were the common pathogens.

Temporal trends in the incidence of HIV infection in antenatal clinic attendees in Addis Ababa, Ethiopia, 1995-2003

BACKGROUND

The HIV incidence data are relevant in depicting the current dynamics and trend of the epidemic. Using a new laboratory method for HIV-1 incidence, we aimed at estimating a 10-year trend in HIV-1 incidence in Addis Ababa, Ethiopia.

METHODS

We determined the temporal trends in HIV incidence based on a total of 7744 serum specimens from pregnant women who attended antenatal clinics in Addis Ababa between 1995 and 2003. HIV incidence was determined by IgG-capture HIV-1 BED incidence enzyme immunoassay following a validation using a well-characterized panel of serial serum specimens from subtype C-infected seroconverters.

FINDINGS

Of the 1350 HIV+ specimens tested as part of the annual sentinel survey between 1995 and 2003, a total of 1332 (98.7%) were tested by BED HIV-1 incidence assay. The incidence rate of HIV-1 infection declined significantly from 7.7% (95% CI, 3.9-11.5%) in 1995 to 2.0% (95% CI, 0.7-3.3%) in 2003. Although there was a trend, amongst the age group of 15-29 years, in age-specific decline in incidence, it was not statistically significant. No change in HIV incidence rate was observed for the group aged above 30 years.

INTERPRETATION

A corresponding decline in the incidence of HIV infection was observed with the decline in the prevalence of HIV infection between 1995 and 2003 in Addis Ababa City. Whether the declines were because of changes in sexual behaviours or other reasons needs to be explored. The BED HIV-1 incidence assay provides a valuable tool in obtaining information on recent HIV-1 infection.

Use of dried spots of whole blood, plasma, and mother's milk collected on filter paper for measurement of human immunodeficiency virus type 1 burden

We studied the use of dried spots of bodily fluids (plasma, whole blood, and mother's milk) on filter paper as a means of sample collection and storage for human immunodeficiency virus type 1 (HIV-1) viral load testing under stringent field conditions. Plasma placed directly in lysis buffer, which is customarily used for viral load assays, was used for comparison in all our experiments. Utilizing reconstruction experiments, we demonstrate no statistical differences between viral loads determined for plasma and mother's milk spotted on filter paper and those for the same fluids placed directly in lysis buffer. We found that the addition of whole blood directly to lysis buffer was unreliable and could not be considered a feasible option. However, viral load measurements for whole blood spotted onto filter paper correlated with plasma viral load values for both filter spots and lysis buffer (Pearson correlation coefficients, 0.7706 and 0.8155, respectively). In conclusion, dried spots of plasma, whole blood, or mother's milk provide a feasible means for the collection, storage, and shipment of samples for subsequent viral load measurement and monitoring. Virus material spotted and dried on filter paper is a good inexpensive alternative for collecting patient material to monitor the HIV-1 viral load. Measuring the HIV-1 burden from whole blood dried on filter paper provides a suitable alternative for low-technology settings with limited access to refrigeration, as can be found in sub-Saharan Africa.

Leishmania aethiopica: identification and characterization of cathepsin L-like cysteine protease genes

There is limited information on the biology and pathogenesis of Leishmania aethiopica, causative agent of cutaneous leishmaniasis (CL) in Ethiopia. In this study we have identified and characterized two cathepsin L-like cysteine protease genes, Laecpa and Laecpb, from L. aethiopica. The predicted amino acid sequence of Laecpa and Laecpb is more than 75% identical with homologous cathepsin L-like cysteine protease genes of other Leishmania species and less than 50% identical with human cathepsin L. Laecpa is expressed predominantly in the stationary, and to a lower level, during the amastigote stage while Laecpb is specifically expressed in the stationary stage of L. aethiopica development. Phylogenetic analysis showed that the two genes are grouped into separate clades which are the result of gene duplication. The isolation of these genes will be useful in developing Leishmania species specific diagnostics for molecular epidemiological studies and serves as a first step to study the role of cysteine proteases in L. aethiopica pathogenesis.

Clinico-mycological Profile of Dermatophytosis in a Reference Centre for Leprosy and Dermatological Diseases in Addis Ababa

To assess the clinical and fungal species spectrum of dermatophyte infection in a reference centre in Addis Ababa, 539 dermatological patients with signs of dermatophytosis were investigated. Seventy-one percent were female and 29% male, aged 2-66 years (median 9). Four hundred-fifteen (77%) had at least one skin lesion. Tinea capitis was diagnosed in 138/155 males (89%) as compared to 214/384 females (40%) (p < 0.05). T. capitis was diagnosed in 69% of the 374 children. Fingernails were affected in 132/145 (91%) of onychomycosis, 118 (90%) of these patients were females and 14 males (p < 0.05). Tinea corporis was observed in 45, and other types of tinea in 12 patients. Thirty-six percent of all patients had also other skin lesions, mostly impetigo. Of 490 cultured samples 364 (74%) grew dermatophytes: Trichophyton violaceum in 84%, Trichophyton verrucosum in 9.6%, Trichophyton tonsurans in 1.4% and T. rubrum in 0.5%. Additionally, 15 isolates were identified as white variants of T. violaceum, in 3 cases confirmed by sequencing of the rDNA ITS 2 region. T. capitis in young males and T. unguium of fingernails in females were the most common manifestations of dermatophytosis in Addis Ababa, usually caused by T.violaceum.

Surveillance technology for HIV-1 subtype C in Ethiopia: an env-based NASBA molecular beacon assay to discriminate between subcluster C and C'

Forty-nine samples with known C2V3 sequences were used for the evaluation of an env-based molecular beacon assay to distinguish between the two genetic subclusters C and C' which characterize the HIV-1 epidemic in Ethiopia. Two subcluster C and two subcluster C' beacons targeting two different loci in the C2V3 region were developed. Using a three beacon-based (2C and 1C'=C prime), isothermal amplification assay, concordance with DNA sequencing was achieved for 43 (87.8%) samples. Sensitivity was 81.8% and specificity 97.4% for subcluster C beacons. For the subcluster C' beacon, a sensitivity of 97% and a specificity of 87.5% was achieved. Five samples were ambiguous by sequencing of which two samples were subcluster C' by the beacon assay and one subcluster C. Two of the samples remained ambiguous with different beacon-pair combinations as well. From samples with a clear C or C' phylogeny by sequencing, three were undetected by the first-line beacon genotyping assay. Genotype ambiguity was resolved in the three samples using beacon pair combinations restricted to each targeted locus. The beacons were evaluated further in a panel including all HIV-1 subtypes. Four of five subtype C isolates were identified correctly, and no cross-reactivity was observed with other subtypes.

Potential for medical transmission of HIV in Ethiopia

The potential medical transmission of HIV through unsafe medical injections was evaluated in 16 rural health institutions in Ethiopia. Most institutions reported re-using disposable needle/syringes, and 12% of observed injections were given with used, disposable syringes prepared for re-use. Analysis of used needle flushes showed no HIV RNA; however, the sensitivity of our method was limited. Despite the re-use of disposable needles, medical injection practices are not likely to contribute significantly to HIV transmission in this region.

Dermatophytosis in Tulugudu Island, Ethiopia

The objective of this investigation was to assess the prevalence of dermatophytoses in children in a geographically restricted area in the Ethiopian countryside, and to determine the aetiological agents of these infections. Demographical and clinical-dermatological data were collected from all children 4-15 years of age on Tulugudu Island, Southern Ethiopia. Mycological specimens were taken and species identification determined through morphological observations and biochemical tests, complemented with sequencing of rDNA ITS2 region when necessary. Of 171 children, 96% shared combs, 85% shared beds and 97% had animal contact. Family size was > 5 persons in 50% of the test subjects and prevalence of tinea capitis was elevated in this group (P < 0.005). Dermatophytoses were clinically diagnosed in 136 cases (79.5%). Tinea capitis (T. capitis) was the most common manifestation with 104 cases (76.5%). T. capitis was combined with dermatophytic infections at other sites in 19 cases. Tinea faciae and Tinea corporis were found in four and two cases, respectively, and pediculosis capitis was diagnosed in 2.9% of the test subjects. Of 135 samples from hair (n = 112), skin (n = 19) and finger-nail (n = 4), 74.1% were microscopy-positive for dermatophytes, 73% were positive in culture, giving an overall prevalence of dermatophytoses in 57.3% of all children examined. Trichophyton violaceum was identified in 80.6% of cultures, Trichophyton verrucosum in 16.3% and Trichophyton tonsurans in 2.0%. One isolate was identified as a white variant of T. violaceum. Tinea capitis was highly prevalent in children on Tulugudu Island, Southern Ethiopia. The anthropophilic species T. violaceum dominated as an aetiological agent. Zoophilic dermatophytes were relatively rarely isolated from clinical specimens, despite the children's frequent contact with animals.

Prevalence of Helicobacter pylori vacA and cagA genotypes in Ethiopian dyspeptic patients

A total of 300 gastric biopsy samples and 50 Helicobacter pylori isolates were collected from Ethiopian adult dyspeptic patients. The vacA and cagA genes were detected in 90 and 79% of biopsy specimens, respectively, and in 100 and 87% of clinical isolates, respectively. Both genes were detected in 84% of the gastric biopsy samples and in 87% of the clinical isolates. Among vacA genotypes, the s1/m1 genotype was the most common in gastric biopsy samples (48%). The vacA and cagA positive H. pylori strains were detected to a higher degree in patients with chronic active gastritis (71%) than patients with other histopathological findings (29%) (P < 0.05).

Transmission of herpes simplex virus Type 2 among factory workers in Ethiopia

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.

Effect of rpoB mutations conferring rifampin resistance on fitness of Mycobacterium tuberculosis

Rifampin is a major drug used in the treatment of tuberculosis infections, and increasing rifampin resistance represents a worldwide clinical problem. Resistance to rifampin is caused by mutations in the rpoB gene, encoding the beta-subunit of RNA polymerase. We examined the effect of three different rpoB mutations on the fitness of Mycobacterium tuberculosis. Rifampin-resistant mutants were isolated from a virulent clinical isolate of M. tuberculosis (strain Harlingen) in vitro at a mutation frequency of 2.3 x 10(-8). Mutations in the rpoB gene were identified, and the growth rates of three defined mutants were measured by competition with the susceptible parent strain in laboratory medium and by single cultures in a macrophage cell line and in laboratory medium. All of the mutants showed a decreased growth rate in the three assays. The relative fitness of the mutants varied between 0.29 and 0.96 (that of the susceptible strain was set to 1.0) depending on the specific mutant and assay system. Unexpectedly, the relative fitness ranking of the mutants differed between the different assays. In conclusion, rifampin resistance is associated with a cost that is conditional.

Prevalence of Helicobacter pylori infection among adult dyspeptic patients in Ethiopia

In developing countries such as Ethiopia, where chronic gastritis and peptic-ulcer disease are the most common endoscopic findings, it is important to study the association between Helicobacter pylori infection and gastroduodenal diseases. Both invasive and non-invasive diagnostic methods were therefore used to investigate 300, consecutive, adult patients with dyspepsia, from the gastrointestinal clinic of Tikur Anbassa University Hospital, Addis Ababa. The apparent overall prevalence of H. pylori infection varied according to the detection method employed. Culture revealed H. pylori in only 69% of the patients but this pathogen appeared more common when rapid urease tests (71%), PCR-denaturating gradient gel electrophoresis (91%), histopathology (81%), silver staining (75%) or stool-antigen tests (81%) were employed. Antibodies to H. pylori were detected, both by enzyme immuno-assay (EIA) and immunoblotting, in approximately 80% of the patients, whether the antigens used were of a reference strain or from a local isolate of H. pylori. When some of the EIA-positive and EIA-negative sera were cross-absorbed with antigens of Campylobacter jejuni and re-tested by EIA, the H. pylori-positive sera remained positive and the negative sera remained negative. Dyspeptic patients in Ethiopia, like most of those previously observed elsewhere in Africa, are often infected with H. pylori. It is important that the management of these patients should not be hampered by the misinterpretation of the African epidemiology of this pathogen.

Phenotypic and genotypic comparisons of CCR5- and CXCR4-tropic human immunodeficiency virus type 1 biological clones isolated from subtype C-infected individuals

Individuals infected with human immunodeficiency virus type 1 (HIV-1) subtype C infrequently harbour X4 viruses. We studied R5 and X4 biological clones generated from HIV-1 subtype C-infected individuals. All subtype C R5 viruses demonstrated slower profiles of replication on CD4(+) lymphocytes in comparison to subtype B viruses, whereas subtype C X4 viruses replicated with comparable efficiency to subtype B X4 viruses. No differences were identified in CC or CXC chemokine inhibitions (RANTES and SDF-1alpha, respectively) between subtype C and subtype B viruses. Immature dendritic cells were shown in coculture experiments to similarly enhance the infection of subtype C and subtype B R5 as well as X4 viruses. By amino acid sequence analysis, we showed that the R5 and X4 subtype C gp120 envelope gene alterations were similar to those for a switching subtype B virus, specifically with respect to the V3 charge and envelope N-linked glycosylation patterns. By phylogenetic analysis, we showed that one patient was infected with HIV-1 C' and the other was infected with HIV-1 C" and that one of the patients harbored a virus that was a recombinant in the gp120 env gene between an R5 and an X4 virus, with the resultant virus being R5. No differences were identified between the long terminal repeat regions of the subtype C R5 and X4 biological clones. These results indicate that even though R5 subtype C viruses are restrictive for virus replication, the R5-to-X4 phenotype switch can occur and does so in a manner similar to that of subtype B viruses.

Antimicrobial susceptibility pattern of Helicobacter pylori strains isolated from adult dyspeptic patients in Tikur Anbassa University Hospital, Addis Ababa, Ethiopia

Presently, there is no published information on the antimicrobial susceptibility pattern of H. pylori strains in Ethiopia to guide the choice of drug for therapy. Therefore, it is becoming clinically relevant to test the in vitro susceptibility of H. pylori clinical isolates prior to treating patients. Susceptibility testing was performed on 50 clinical H. pylori isolates obtained from adult dyspeptic patients referred to the gastrointestinal (GI) Clinic of Tikur Anbassa University Hospital. Five antibiotics were evaluated, by using the Episolmeter test (E-test). The antibiogram of 50 H. pylori clinical isolates showed that all strains were sensitive to clarithromycin, erythromycin and tetracycline, while 38/50 (76%) and 3/50 (6%) of the strains were resistant to metronidazole and amoxicillin, respectively. Infection by metronidazole or amoxicillin resistant H. pylori is an important factor leading to treatment failure. Testing of all H. pylori clinical isolates to metronidazole and amoxicillin is recommended. If it is not possible to perform susceptibility tests on each clinical isolate, a program to survey the prevalence of resistance should be implemented in a given area or population. When treatment of H. pylori infection is indicated in dyspeptic patients, the potential availability, simplicity of use, safety and low cost of the antimicrobial agents have to be taken into account.

Development of a nucleic acid sequence-based amplification assay that uses gag-based molecular beacons to distinguish between human immunodeficiency virus type 1 subtype C and C' infections in Ethiopia

A gag-based molecular beacon assay utilizing real-time nucleic acid sequence-based amplification technology has been developed to differentiate between the two genetic subclusters of human immunodeficiency virus type 1 (HIV-1) subtype C (C and C') circulating in Ethiopia. Of 41 samples, 36 could be classified as C or C' by sequencing of the gag gene. All 36 isolates were correctly identified by the gag beacon test. Three isolates with genomes that were recombinant in gag were unambiguously typed as belonging to the C' subcluster. Further analysis revealed that these contained the most sequence homology with a reference subcluster C' sequence in the target region of the beacon and hence were correct for the analyzed region. For one sample, sequencing and gag molecular beacon results did not match, while another isolate could not be detected at all by the beacon assay. Overall, high levels of sensitivity and specificity were achieved for both beacons (90.5% sensitivity and 100% specificity for the C beacon and 100% sensitivity and 95.2% specificity for the C' beacon). The availability of a diagnostic test which can quickly and reliably discriminate between C and C' HIV-1 infections in Ethiopia is an important first step toward studying their respective biological characteristics. As the assay is specific to the Ethiopian HIV-1 subtype C epidemic, it will contribute to characterizing the circulating viruses in this population, thereby generating the information necessary for the development of a potential efficacious HIV-1 vaccine appropriate for the Ethiopian context.

Recombination of HIV type 1C (C'/C") in Ethiopia: possible link of EthHIV-1C' to subtype C sequences from the high-prevalence epidemics in India and Southern Africa

The magnitude and complexity of the HIV-1 genetic diversity are major challenges for vaccine development. Investigation of the genotypes circulating in areas of high incidence, as well as their interactions, will be a milestone in the development of an efficacious vaccine. Because HIV-1 subtype C (HIV-1C) is responsible for most of the 36 million infections worldwide we investigated the HIV-1C strains circulating in Ethiopia in a retrospective, cross-sectional study. Serum samples from HIV-1-positive individuals were collected in seven Ethiopian cities and towns. Nucleotide sequences of the gag, pol, and env genes were analyzed. We performed phylogenetic analysis by the neighbor-joining and maximum-likelihood methods with sequences from 30 isolates, and we determined recombination by the bootscanning method as implemented in the SIMPLOT program. Sequence analyses of a 2600-nucleotide fragment (including the gag gene, the protease, and the 5' half of reverse transcriptase of the pol gene) and the corresponding V1V2/C2V3 envelope regions confirmed that two distinct HIV-1C genotypes (C' and C") are cocirculating in Ethiopia, as shown previously by the analysis of the C2V3 envelope region. We have identified intrasubtype recombination between the two HIV-1C genotypes, C' and C", with 6 of the 30 (20%) analyzed viruses being recombinants. The C' sequences were phylogenetically linked to the fast spreading viruses in India and southern Africa. Furthermore, all the recombinant viruses shared the C' V1V3 region of the envelope, suggesting that the prevalence of viruses with the C' envelope is increasing compared to the C" envelope. The possibility that viruses with a C' envelope have a biological advantage over the viruses with a C" envelope should be further investigated in biological and epidemiological studies.

The E1E4 protein of human papillomavirus type 16 associates with a putative RNA helicase through sequences in its C terminus

Human papillomavirus type 16 (HPV16) infects cervical epithelium and is associated with the majority of cervical cancers. The E1E4 protein of HPV16 but not those of HPV1 or HPV6 was found to associate with a novel member of the DEAD box protein family of RNA helicases through sequences in its C terminus. This protein, termed E4-DBP (E4-DEAD box protein), has a molecular weight of 66,000 (66K) and can shuttle between the nucleus and the cytoplasm. It binds to RNA in vitro, including the major HPV16 late transcript (E1E4. L1), and has an RNA-independent ATPase activity which can be partially inhibited by E1E4. E4-DBP was detectable in the cytoplasm of cells expressing HPV16 E1E4 (in vivo and in vitro) and could be immunoprecipitated as an E1E4 complex from cervical epithelial cell lines. In cell lines lacking cytoplasmic intermediate filaments, loss of the leucine cluster-cytoplasmic anchor region of HPV16 E1wedgeE4 resulted in both proteins colocalizing exclusively to the nucleoli. Two additional HPV16 E1E4-binding proteins, of 80K and 50K, were identified in pull-down experiments but were not recognized by antibodies to E4-DBP or the conserved DEAD box motif. Sequence analysis of E4-DBP revealed homology in its E4-binding region with three Escherichia coli DEAD box proteins involved in the regulation of mRNA stability and degradation (RhlB, SrmB, and DeaD) and with the Rrp3 protein of Saccharomyces cerevisiae, which is involved in ribosome biogenesis. The synthesis of HPV16 coat proteins occurs after E1E4 expression and genome amplification and is regulated at the level of mRNA stability and translation. Identification of E4-DBP as an HPV16 E1E4-associated protein indicates a possible role for E1E4 in virus synthesis.

In vitro susceptibility of gram-negative bacterial isolates to chlorhexidine gluconate

OBJECTIVE

To investigate the susceptibility of clinical isolates of gram-negative bacteria to chlorhexidine gluconate.

DESIGN

Prospective laboratory study.

SETTING

Tikur Anbessa Hospital, Addis Ababa, Ethiopia.

SUBJECTS

Clinical specimens from 443 hospital patients.

MAIN OUTCOME MEASURES

Significant number of gram negative bacteria were not inhibited by chlorhexidine gluconate (0.02-0.05%) used for antisepsis.

RESULTS

Four hundred and forty three strains of gram-negative bacteria were isolated from Tikur Anbessa Hospital patients. Escherichia coli (31.6%) and Klebsiella pneumoniae (23%) were the most frequently isolated bacteria followed by Proteus species (13.3%), Pseudomonas species (9.2%), and Citrobacter species (6.1%). Each organism was tested to chlorhexidine gluconate (CHG), minimum inhibitory concentration (MIC) ranging from 0.0001% to 1%w/v. All Salmonella species and E. coli were inhibited by CHG, MIC < or = 0.01%. Twenty nine per cent of Acinetobacter, 28% of K. pneumoniae and Enterobacter species and 19-25% of Pseudomonas, Proteus and Providencia species were only inhibited at high concentrations of CHG (> or = 0.1%).

CONCLUSION

Our results showed that a significant number of the gram-negative bacterial isolates were not inhibited by CHG at the concentration used for disinfection of wounds or instruments (MIC 0.02-0.05% w/v). It is therefore important to select appropriate concentration of this disinfectant and rationally use it for disinfection and hospital hygiene. Continuing follow up and surveillance is also needed to detect resistant bacteria to chlorhexidine or other disinfectants in time.

Salmonella serogroups identified from adult diarrhoeal out-patients in Addis Ababa, Ethiopia: antibiotic resistance and plasmid profile analysis

Forty five Salmonella strains were isolated from 700 diarrhoeal samples collected from adult diarrhoeal out-patients in Addis Ababa. Among the isolates, serogroup C comprised 31.1%, B 24.4%, S.typhi 15.6%, D 13.3%, A 8.9% and E 6.7%. Among the isolates, 71.1% were resistant to tetracycline, 68.9% to ampicillin, 66.7% to cephalothin, 57.8% to trimethoprim-sulphamethoxazole, 53.9% to kanamycin, 46.7% to chloramphenicol and less than 31.8% of the isolates were resistant to other drugs. Among S.typhi isolates, 28.6% were resistant to chloramphenicol and this shows the emergence of chloramphenicol resistant S.typhi strains in Ethiopia. Gentamicin and polymyxin B were found to be the drugs of choice for cases of salmonellosis including S.typhi. All drug resistant isolates analysed for plasmids contained multiple plasmids ranging in sizes from 1.8 to greater than 21 Kilobases.

Shigella serogroups identified from adult diarrhoeal out-patients in Addis Ababa, Ethiopia: antibiotic resistance and plasmid profile analysis

Fifty shigella strains were isolated from 700 diarrhoeal samples collected from adult diarrhoeal out-patients in Addis Ababa. Among the isolates, serogroup A comprised 28%, B 44%, C 18% and D 10%. Among all shigella serogroups, highest resistance was encountered to tetracycline (74%), ampicillin (70%), cephalothin (64%), trimethoprim-sulfamethoxazole (52%) and chloramphenicol (50%) while least resistance was observed to gentamicin (0%), polymyxin B (10%) and nalidixic acid (14%). Gentamicin, polymyxin B and nalidixic acid were found to be the drugs of choice for cases of shigellosis. All drug resistant isolates analysed for plasmids contained multiple plasmids ranging from 1.8 to greater than 21 Kilobases.

Continuous culture studies on the synthesis of capsular polysaccharide by Klebsiella pneumoniae K1

The synthesis of capsular polysaccharide by Klebsiella pneumoniae K1 was investigated in a minimal salts medium by continuous culture. The organism produced larger amounts of polysaccharide under nitrogen-limited conditions than under carbon-limited conditions. The synthesis of polysaccharide was dependent not only on the availability of excess carbon, but also on growth rate. The rate of polysaccharide synthesis was greatest at low dilutions, low temperature (30 degrees C) and at neutral pH. Prolonged growth in nitrogen-limited culture resulted in the development of non-mucoid variants, possibly due to a selective growth advantage over mucoid cells. The non-mucoid isolate was more susceptible to some bacteriophages, possibly due to the reduction nor absence of capsular polysaccharide.

Aerobic gram-negative pharyngeal bacilli of adult Ethiopians: carrier rates and antibiograms

One thousand pharyngeal swab specimens were processed for aerobic culture to determine the carriage rate of Gram-negative bacilli (GNB). The isolates were identified and their sensitivity determined to 11 antibacterial drugs following standard techniques. Similar pharyngeal carriage rates of GNB were found among the various groups of healthy subjects. Patients had higher colonization rates (27%) than healthy subjects (16%). The increase in prevalence of GNB seemed to be associated with underlying diseases and duration of hospitalization. Klebsiella (36%) was the most frequent genus amongst the 215 isolates of GNB followed by pseudomonas (13%), enterobacter (13%) and acinetobacter (10%). Others were less frequently isolated. Over 70% of all isolates were resistant to ampicillin (79%) and carbenicillin (72%); 55, 45 and 43% were resistant to cephalothin, tetracycline and streptomycin, respectively. The great majority of the strains were sensitive to the remaining six drugs. The hospital isolates were more resistant than the non-hospital isolates to most drugs tested. The hospital strains were also more often multiply resistant (89%) than the non-hospital strains (60%). Sixty-five different resistance antibiograms of 1-10 drugs were observed among 191 strains. More varied types of antibiograms were observed among hospital strains. The high frequency of multiple drug resistance of the isolates is an indication of the extensive use of antibacterial drugs, indicating the need for a policy for judicious use of drugs.