Comparison of the performance of rapid HIV tests using samples collected for surveillance in Mozambique.

Mozambique had low HIV prevalence until the mid-1990s, but recent data indicate increasing rates. There is little information on HIV-2. Therefore, HIV seroprevalence was assessed among pregnant women and field-ready HIV diagnostic strategies were evaluated. A total of 6,930 samples collected by three health centers from 2002 to 2005 were tested on site by nurses with two simple/rapid tests, Determine HIV-1/2 (Abbott Laboratories; screening) and Uni-Gold HIV (Trinity Biotech; confirmation), which is the national HIV testing strategy. The prevalence of HIV was 14.0% (2002), 17.8% (2003), 16.5% (2004), and 20.2% (2005). A subset of 888 samples collected 2003 was sent to the Central Microbiology Laboratory, Maputo for evaluation of tests and testing strategies. The assays included for comparison were Capillus HIV-1/HIV-2 (Trinity Biotech), DoubleCheckGold HIV-1&2 (Orgenics) and Enzygnost Anti-HIV-1/2 Plus (Behringwerke, reference ELISA). Confirmation of reactive samples was done by Uni-Gold HIV and ImmunoComb II HIV-1&2 BiSpot (for HIV type differentiation). The Capillus HIV-1/ HIV-2 + ImmunoComb II HIV-1&2 BiSpot combination was the gold standard. The sensitivity of the rapid/simple screening assays (Determine HIV-1/2, DoubleCheckGold HIV-1&2) was 100% (N = 160) and their (initial) specificities were 99.6% and 99.7%, respectively. Repeated testing and combinations of assays increased the specificity. Four suspected cases of recent seroconversion were found. Together with the increasing prevalence rates, this may indicate that Mozambique is a high-incidence area, although further studies are needed to confirm this. Testing strategies for on-site screening and confirmation based on the combination of Determine HIV-1/2, Uni-Gold HIV and DoubleCheckGold HIV-1&2 are well suited for local field use.

HIV-1 genetic diversity and transmitted drug resistance in health care settings in Maputo, Mozambique.

OBJECTIVES: To characterize HIV-1 diversity and transmitted drug resistance in persons with access to care and treatment in Maputo, Mozambique. METHODS: Samples were collected in 2002-2004 from 144 drug-naive patients attending public hospitals and private clinics. Plasma viremia, CD4, and CD8 cell counts were determined for each patient. The Stanford Algorithm was used for resistance genotyping on pol sequences. Subtyping was done by phylogenetic analysis. RESULTS: Most patients had high viral load (mean, 5.0 log copies/mL) and low CD4 cell counts (median, 260 CD4 cells/microL). Protease and/or reverse transcriptase sequences were obtained from 104 (72%) samples. Patients harbored subtypes C (80.8%), G (3.8%), CRF37_cpx (6.7%), untypable (U) (1.0%), and recombinant strains (7.7%) comprising the A, C, D, F, and U clades. There were no major protease inhibitor resistance mutations. Mutations conferring resistance to the nucleoside/nucleotide reverse transcriptase inhibitors and/or nonnucleoside reverse transcriptase inhibitors were found in 4 (4/68; 5.9%) patients. Phylogenetic analysis suggested an imported origin for 2 resistant variants. CONCLUSIONS: The HIV-1 epidemic in Maputo is evolving rapidly in genetic complexity due to the recent introduction of all major subtypes and recombinant forms. Continued surveillance of drug resistance in treated and untreated populations is needed to prevent further transmission of HIV drug-resistant variants and maximize the efficacy of antiretroviral therapy in Maputo.

Use of replacement blood donors to study the epidemiology of major blood-borne viruses in the general population of Maputo, Mozambique.

The seroprevalence rates of human immunodeficiency virus (HIV), human T-cell leukemia/lymphoma virus (HTLV), hepatitis B virus (HBV), hepatitis D virus (HDV), and hepatitis C virus (HCV) in Mozambique are poorly documented. The epidemiology of these infections was studied in the Maputo region. All donors attending the blood bank during the study period were interviewed and underwent serological and molecular tests for markers of virus exposure. Thus, 1,578 consecutive replacement blood donors were investigated, as they undergo no selection (other than their relation with a patient needing a transfusion), and may thus provide reliable estimates of the prevalence rates in the general population. The age-standardized prevalence rates among 15- to 49-year-old men and women were, respectively, 12.3 and 15.4% for HIV and 0.9 and 1.2% for HTLV. Low educational status (P = 0.014) and tattooing/scarification (P = 0.023) were predictive of HIV infection in multivariate analysis. The age-adjusted prevalence rates of markers of hepatotropic virus among men and women were, respectively, 10.6 and 4.5% for hepatitis B surface antigen (HBsAg), 1.2 and 1.0% for anti-HCV, and 0 and 0% for anti-HDV. Two percent of donors had viral co-infections, involving most frequently the combination of HIV and HBsAg +. A significant association was found between anti-HIV and anti-HBc (P = 0.012). HBsAg was associated with the place of birth (P = 0.011) and a history of transfusion (P = 0.069). Smokers had higher seroprevalence rates than nonsmokers for HIV (P < 0.0001) and HBsAg (P = 0.045). Genotype A was the most frequent HBV genotype (86.3%) followed by E and D. HCV genotypes were 1a, 1b, 3a, and 5a. These results show that HBV vaccination and HIV-preventive measures need to be reinforced in Mozambique.

Sporadic methicillin resistance in community acquired Staphylococcus aureus in Mozambique.

This study reports the drug resistance and clonal relationship of 24 Staphylococcus aureus community acquired isolates from patients attending Maputo Central Hospital, Mozambique, during one year (2002-2003). All the isolates produced beta-lactamase, six strains were resistant to tetracycline alone, three were resistant to erythromycin alone and one was resistant to trimethoprim-sulfamethoxazole; 11 were susceptible to all other drugs tested. Only one strain showed a multiple resistance pattern, including methicillin resistance. To investigate the clonal relationships we applied the ERIC AP-PCR and the SmaI PFGE RFLP methods. Overlapping drug resistances with these two molecular profiles, no significant correlation was obtained. The emergence of methicillin resistance in a multiple resistant strain is of great concern for resistance spreading surveillance in Mozambique.