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Objectives In 2011, a consensus was reached defining 'late presenters' ( LPs) as individuals presenting for care with a CD4 count < 350 cells/μL or with an AIDS-defining event, regardless of CD4 count. However, a transient low CD4 count is not uncommon in recent infections. The objective of this study was to investigate how measurements of late presentation change if the clinical stage at the time of diagnosis is taken into account. Methods Case surveillance data for newly diagnosed patients in Belgium in 1998-2012 were analysed, including CD4 count at diagnosis, the presence of AIDS-defining events, and recent infections (< 6 months) as reported by clinicians in the case of acute illness or a recent negative test. First, proportions of LPs were calculated according to the consensus definition. Secondly, LPs were reclassified as 'nonlate' if infections were reported as recent. Results A total of 7949 HIV diagnoses were included in the study. Recent infections were increasingly reported over time, accounting for 8.2% of new infections in 1998 and 37.5% in 2012. The consideration of clinical stage significantly modified the proportion of LPs: 18.2% of men who have sex with men ( MSM) diagnosed in 2012 would be classified as LPs instead of 30.9% using the consensus definition ( P < 0.001). The proportion of patients misclassified as LPs increased significantly over time: 5% in MSM in 1998 vs. 41% in 2012. Conclusions This study suggests that low CD4 counts in recent infections may lead to overestimation of late presentation when applying the consensus definition. The impact of transient CD4 count on late presentation estimates should be assessed and, if relevant, the introduction of clinical stage in the definition of late presentation should be considered. [ABSTRACT FROM AUTHOR]

Background: The Belgian HIV epidemic is largely concentrated among men who have sex with men and Sub-Saharan Africans. We studied the continuum of HIV care of those diagnosed with HIV living in Belgium and its associated factors.Methods: Data on new HIV diagnoses 2007-2010 and HIV-infected patients in care in 2010-2011 were analysed. Proportions were estimated for each sequential stage of the continuum of HIV care and factors associated with attrition at each stage were studied.Results: Of all HIV diagnosed patients living in Belgium in 2011, an estimated 98.2% were linked to HIV care, 90.8% were retained in care, 83.3% received antiretroviral therapy and 69.5% had an undetectable viral load (<50 copies/ml). After adjustment for sex, age at diagnosis, nationality and mode of transmission, we found lower entry into care in non-Belgians and after preoperative HIV diagnoses; lower retention in non-Belgians and injecting drug users; higher retention in men who have sex with men and among those on ART. Younger patients had lower antiretroviral therapy uptake and less viral suppression; those with longer time from diagnosis had higher ART uptake and more viral suppression; Sub-Saharan Africans on ART had slightly less viral suppression.Conclusions: The continuum of HIV care in Belgium presents low attrition rates over all stages. The undiagnosed HIV-infected population, although not precisely estimated, but probably close to 20% based on available survey and surveillance results, could be the weakest stage of the continuum of HIV care. Its identification is a priority along with improving the HIV care continuum of migrants. [ABSTRACT FROM AUTHOR]

Objectives Transmitted HIV strains may harbour drug resistance mutations. HIV-1 drug resistance mutations are currently detected in plasma viral RNA. HIV-1 proviral DNA could be an alternative marker, as it persists in infected cells. Methods This was a prospective study assessing the prevalence and persistence of HIV-1 drug resistance mutations in DNA from CD4 cells before and after protease inhibitor (PI)- or nonnucleoside reverse transcriptase inhibitor (NNRTI)-based therapy initiation in 69 drug-naïve patients. Results Before therapy, 90 and 66% of detected mutations were present in CD4 cells and plasma, respectively. We detected seven key mutations, and four of these (M184M/V, M184M/I, K103K/N and M46M/I) were only found in the cells. When treatment was started, 40 patients were followed; the mutations detected at the naïve stage remained present for at least 1 year. Under successful treatment, new key mutations emerged in CD4 cells (M184I, M184M/I and Y188Y/H). Conclusions The proportion of mutations detected in the DNA was statistically significantly higher than that detected in standard RNA genotyping, and these mutations persisted for at least 1 year irrespective of therapy. The pre-existence of resistance mutations did not jeopardise treatment outcome when the drug concerned was not included in the regimen. Analysis of HIV-1 DNA could be useful in chronic infections or when switching therapy in patients with undetectable viraemia. [ABSTRACT FROM AUTHOR]

We hypothetized that in the African rainforest (Cameroon), one of the principal limiting factors for termite multiplication is the relative scarcity of nesting sites. As a consequence, termitaries of Cubitermes fungifaber, C. banksi and C. subarquatus with their alveolate structure might constitute good shelters for incipient societies. In the cavities of these termitaries we recorded 29 termite species (including conspecifics) belonging to 23 genera and 5 subfamilies. Active Cubitermes fungifaber and C. banksi termitaries shelter fewer incipient and adult societies than abandoned ones. Active C. subarquatus termitaries shelter more incipient societies than abandoned ones, while the difference is not significant with regards to termite societies at other stages of development. The frequency of sheltered Cubitermes spp. incipient societies was so large (72.3%) that we suggest that abandoned termitaries and unoccupied zones of active ones had an adaptative value at the generic level as they constitute good shelters (probably the best) for incipient societies and favour reproduction in Cubitermes spp. societies. [ABSTRACT FROM AUTHOR]

Various items are complicating the treatment of HIV-2 infected patients. Compared to HIV-1 there is much less treatment experience, no evidence from randomized control trials, a reduced number of effective drugs and no broadly available test for viral load monitoring. In case of treatment failure there is only limited guidance and presently no easy accessible tool for nucleic acid sequence interpretation available. To solve this problem, we initiated an expert workshop to address some of these problems. A panel of experts from four different European countries voted on a rule set for interpretation of mutations in the HIV-2 protease, reverse transcriptase and integrase. Rules were proposed by each member and were then modified during discussion by considering data gained from HIV-1 and accumulated experience of the follow up of HIV-2-infected patients. Based on the HIV-GRADE internet-tool an online tool was developed to make the rule set easily accessible and usable. Rules were laid down for the interpretation of HIV-2 drug resistance to NRTIs, PIs and INIs (integrase inhibitors). Due to natural resistance of HIV-2, usage of NNRTIs and T-20 was not recommended as part of an antiretroviral regimen for HIV-2. These rules were then translated in a machine interpretable format (algorithm specification interface, ASI) and the HIV-GRADE tool was extended for usage of HIV-2 sequences. Further consensus sequences were generated from the reference sequence data set provided by Los Alamos National Laboratories. In contrast to HIV-1, mutations were compared to a group specific consensus sequence (Group A or Group B) and not to a consensus sequence from the most predominant HIV-2 Group A. This change was necessary due to significant differences between the various HIV-2 strains. We developed a rule set and an automated tool for HIV-2 drug resistance analyses. This tool and the rules will be freely available on the internet. Access to the pre-publication versions can be granted by each of the group members. To keep the algorithm rules up-to-date it will be actualized on a yearly basis. [ABSTRACT FROM AUTHOR]

Background We analysed the distribution of an HIV-1 subtype B strain resistant to efavirenz and nevirapine among incident infections in the Belgian population. Method The Belgian AIDS reference laboratories searched their databases for HIV-1 subtype B sequences harbouring the K103N mutation in the reverse transcriptase (RT) or the C67S and V77I mutations in the protease (PR). We included the earliest RT sequence available of drug-naïve patients as well as sequences related to treatment failure. Fifty sequences were aligned omitting the codon 103 and submitted to phylogenetic analysis. Epidemiological data were collected through the Institute of Public Health national database. In addition, three sequences from the cluster were analysed by deep sequencing using the Roche GS Junior platform. Results Phylogenetic analysis revealed the presence of a 24 virus sequences cluster. All except one of those sequences resulted from patients who were ARV-naïve at the time of sampling, and 21 had the K103N mutation. Two thirds of the clustered patients were infected through homosexual or bisexual contacts while the others were heterosexuals. No case was related to migrants contaminated abroad. Fifteen of the clustered patients were diagnosed between January 2011 and June 2012; 87% of them were aged between 20 and 29 at the time of diagnosis. Interestingly, 60% of them reside in the province of Namur. Deep sequencing analysis of 3 individuals sampled near seroconversion revealed no other resistance mutations at a frequency>1% than those already picked up by Sanger sequencing (RT A98S, K103N; PR V77I), except the RT V90I. Conclusion We identified a transmission cluster of drug resistant HIV-1 variants mainly including homo- and heterosexual young adults. Most individuals are of Belgian origin and are living around the city of Namur (Belgium). The K103N mutation had no apparent impact on transmission fitness as its spread raised during the last years. These observations may impact on local prevention and ARV prophylaxis strategies. [ABSTRACT FROM AUTHOR]