Non-Surgical Periodontal Treatment Impact on Subgingival Microbiome and Intra-Oral Halitosis.

The purpose of this study was to characterize and compare subgingival microbiome before and after periodontal treatment to learn if any changes of the subgingival microbiome were reflected in intra-oral halitosis. We tested the hypothesis that intra-oral halitosis (Volatile sulfur compounds levels) correlates with corresponding subgingival bacterial levels before and after periodontal treatment. Twenty patients with generalized periodontitis completed the study. Subgingival plaque samples were collected at baseline and 6-8 weeks after nonsurgical periodontal therapy. Full-mouth periodontal status assessed probing depth (PD), clinical attachment loss (CAL), gingival recession (REC), bleeding on probing (BoP), PISA and PESA. Halitosis assessment was made using a volatile sulfur compounds (VSC) detector device. Periodontal measures were regressed across VSC values using adjusted multivariate linear analysis. The subgingival microbiome was characterized by sequencing on an Illumina platform. From a sample of 20 patients referred to periodontal treatment, 70% were females (n = 14), with a mean age of 56.6 (±10.3) years; full-mouth records of PD, CAL, BOP (%) allowed to classify the stage and grade of periodontitis, with 45% (n = 9) of the sample having Periodontitis Stage IV grade C and 95% (n = 19) had generalized periodontitis. The correlation of bacterial variation with VSCs measured in the periodontal diagnosis and in the reassessment after treatment were evaluated. Fusobacterium nucleatum, Capnocytophaga gingivalis and Campylobacter showaei showed correlation with the reduction of VSC after periodontal treatment (p-value = 0.044; 0.047 and 0.004, respectively). Capnocytophaga sputigena had a significant reverse correlation between VSCs variation from diagnosis (baseline) and after treatment. Microbial diversity was high in the subgingival plaque on periodontitis and intra-oral halitosis participants of the study. Furthermore, there were correlations between subgingival plaque composition and VSC counting after periodontal treatment. The subgingival microbiome can offer important clues in the investigation of the pathogenesis and treatment of halitosis.

An HIV-1/HIV-2 Chimeric Envelope Glycoprotein Generates Binding and Neutralising Antibodies against HIV-1 and HIV-2 Isolates.

The development of immunogens that elicit broadly reactive neutralising antibodies (bNAbs) is the highest priority for an HIV vaccine. We have shown that a prime-boost vaccination strategy with vaccinia virus expressing the envelope glycoprotein gp120 of HIV-2 and a polypeptide comprising the envelope regions C2, V3 and C3 elicits bNAbs against HIV-2. We hypothesised that a chimeric envelope gp120 containing the C2, V3 and C3 regions of HIV-2 and the remaining parts of HIV-1 would elicit a neutralising response against HIV-1 and HIV-2. This chimeric envelope was synthesised and expressed in vaccinia virus. Balb/c mice primed with the recombinant vaccinia virus and boosted with an HIV-2 C2V3C3 polypeptide or monomeric gp120 from a CRF01_AG HIV-1 isolate produced antibodies that neutralised >60% (serum dilution 1:40) of a primary HIV-2 isolate. Four out of nine mice also produced antibodies that neutralised at least one HIV-1 isolate. Neutralising epitope specificity was assessed using a panel of HIV-1 TRO.11 pseudoviruses with key neutralising epitopes disrupted by alanine substitution (N160A in V2; N278A in the CD4 binding site region; N332A in the high mannose patch). The neutralisation of the mutant pseudoviruses was reduced or abolished in one mouse, suggesting that neutralising antibodies target the three major neutralising epitopes in the HIV-1 envelope gp120. These results provide proof of concept for chimeric HIV-1/HIV-2 envelope glycoproteins as vaccine immunogens that can direct the antibody response against neutralising epitopes in the HIV-1 and HIV-2 surface glycoproteins.

Insights into Candida Colonization in Intensive Care Unit Patients: A Prospective Multicenter Study.

The skin mycobiota plays a significant role in infection risk, pathogen transmission, and personalized medicine approaches in intensive care settings. This prospective multicenter study aimed to enhance our understanding of intensive care units' (ICUs') Candida colonization dynamics, identify modifiable risk factors, and assess their impact on survival risk. Specimens were taken from 675, 203, and 110 patients at the admission (D1), 5th (D5), and 8th (D8) days of ICU stay, respectively. The patient's demographic and clinical data were collected. Candida isolates were identified by conventional culture-based microbiology combined with molecular approaches. Overall, colonization was 184/675 (27.3%), 87/203 (42.8%), and 58/110 (52.7%) on D1, D5, and D8, respectively. Candida colonization dynamics were significantly associated with ICU type (odds ratio (OR) = 2.03, 95% CI 1.22-3.39, p = 0.007), respiratory infection (OR = 1.74, 95% CI 1.17-2.58, p = 0.006), hemodialysis (OR = 2.19, 95% CI 1.17-4.10, p = 0.014), COVID-19 (OR = 0.37, 95% CI 0.14-0.99, p = 0.048), and with a poor 3-month outcome (p = 0.008). Skin Candida spp. colonization can be an early warning tool to generate valuable insights into the epidemiology, risk factors, and survival rates of critically ill patients, and should be considered for epidemiological surveillance.

Non-Surgical Periodontal Therapy's Influence on Alpha-Synuclein and Inflammatory Marker Levels: A Pilot Study.

Background: Microbial dysbiosis may contribute to alpha-synuclein (α-Syn) homeostasis disruption, yet the burden of inflammatory periodontal infection and its treatment have never been studied in this regard. We aimed to compare the cytokine and α-Syn levels in the saliva and blood of patients with periodontitis who underwent non-surgical periodontal therapy (NSPT) and those of their healthy counterparts. Methods: Periodontal examination and saliva and blood sample collection were carried out in incoming patients at a university clinic. The periodontitis group (PG) received NSPT. The sample collection and periodontal observation were repeated 30 days after. IL-6, IL1-ß and total α-Syn were quantified using immunoassay methods. The periodontal inflamed surface area (PISA) was calculated as a proxy for periodontal inflammation. Results: Eleven participants formed the PG, and there were fifteen healthy controls (HC). At baseline, no correlation between salivary and plasma α-Syn was found. The salivary α-Syn levels revealed a tendency to decrease 30 days after, particularly in the PD cases. The variation in PISA and α-Syn showed significant correlation. Salivary α-Syn correlated negatively with salivary IL-6 levels at both timepoints in the total sample (rho = -0.394 and rho = -0.451) and in the HC (rho = -0.632 and rho = -0.561). Variations in plasma IL-6 and α-Syn were negatively correlated (rho = -0.518) in the healthy participants. Baseline plasma IL1-ß negatively correlated with plasmatic α-Syn at 30 days in the HC (rho = -0.581). Conclusions: Salivary and plasma α-Syn bioavailability operate independently, and periodontal diagnosis was not a confounding factor. Salivary α-Syn levels were significantly affected by NSPT, contrary to plasma levels. These results should be confirmed in future larger and prospective studies.

Antibacterial Effect of Ozone on Cariogenic Bacteria and Its Potential Prejudicial Effect on Dentin Bond Strength-An In Vitro Study.

Ozone is increasingly utilized in dental caries treatment due to its antibacterial properties. In a context of limited studies and no consensus on protocols, this research aims to assess ozone's antibacterial efficacy on cariogenic bacteria and its potential adverse impact on dentin bond strength. Streptococcus mutans, Streptococcus sobrinus, Lactobacillus casei, and Actinomyces naeslundii suspensions were exposed to 40 µg/mL of ozone gas and 60 µg/mL of ozonated water (80 s) via a medical ozone generator. Negative and positive control groups (chlorhexidine 2%) were included, and UFC/mL counts were recorded. To examine microtensile bond strength (µTBS), 20 human molars were divided into four groups, and class I cavities were created. After ozone application, samples were restored using an etch-and-rinse and resin composite, then sectioned for testing. The SPSS v. 28 program was used with a significance level of 5%. The µTBS results were evaluated using one-way ANOVA, Tukey HSD, and Games-Howell. Bacterial counts reduced from 106 to 101, but dentin µTBS was significantly impacted by ozone (ANOVA, p < 0.001). Despite ozone's attractive antibacterial activity, this study emphasizes its detrimental effect on dentin adhesion, cautioning against its use before restorative treatments.

Evolution of the human immunodeficiency virus type 2 envelope in the first years of infection is associated with the dynamics of the neutralizing antibody response.

BACKGROUND: Differently from HIV-1, HIV-2 disease progression usually takes decades without antiretroviral therapy and the majority of HIV-2 infected individuals survive as elite controllers with normal CD4⁺ T cell counts and low or undetectable plasma viral load. Neutralizing antibodies (Nabs) are thought to play a central role in HIV-2 evolution and pathogenesis. However, the dynamic of the Nab response and resulting HIV-2 escape during acute infection and their impact in HIV-2 evolution and disease progression remain largely unknown. Our objective was to characterize the Nab response and the molecular and phenotypic evolution of HIV-2 in association with Nab escape in the first years of infection in two children infected at birth. RESULTS: CD4⁺ T cells decreased from about 50% to below 30% in both children in the first five years of infection and the infecting R5 viruses were replaced by X4 viruses within the same period. With antiretroviral therapy, viral load in child 1 decreased to undetectable levels and CD4+ T cells recovered to normal levels, which have been sustained at least until the age of 12. In contrast, viral load increased in child 2 and she progressed to AIDS and death at age 9. Beginning in the first year of life, child 1 raised high titers of antibodies that neutralized primary R5 isolates more effectively than X4 isolates, both autologous and heterologous. Child 2 raised a weak X4-specific Nab response that decreased sharply as disease progressed. Rate of evolution, nucleotide and amino acid diversity, and positive selection, were significantly higher in the envelope of child 1 compared to child 2. Rates of R5-to-X4 tropism switch, of V1 and V3 sequence diversification, and of convergence of V3 to a ß-hairpin structure were related with rate of escape from the neutralizing antibodies. CONCLUSION: Our data suggests that the molecular and phenotypic evolution of the human immunodeficiency virus type 2 envelope are related with the dynamics of the neutralizing antibody response providing further support for a model in which Nabs play an important role in HIV-2 pathogenesis.

Association of Herpesvirus and Periodontitis: A Clinical and Laboratorial Case-Control Study.

OBJECTIVES: A significant influence of the Herpesviridae family in the progression of periodontal disease has been suggested. The aim of this study was to investigate the potential association of four Herpesviruses (HSV-1, HSV-2, cytomegalovirus [CMV], and Epstein-Barr virus [EBV]) with periodontal disease using a qualitative test for evaluating the presence or absence of viral DNA in crevicular fluid samples of both healthy periodontal patients and periodontal compromised patients. MATERIALS AND METHODS: A case-control study was conducted in 100 participants at a university clinic. A qualitative test was used for evaluating the presence/absence of viral DNA in crevicular fluid samples of both healthy periodontal patients and periodontal compromised patients, and considering the periodontitis staging (stage II, stage III, and stage IV) and grading (grade A, grade B, and grade C). STATISTICAL ANALYSIS: The distribution of the same exposure variables to the periodontitis staging and grading was compared using Chi-square, Fisher's exact, and Gamma tests depending on the variable characteristics. The significance level was set at 5%. The association of the variables: age, sex, diabetes, smoking, alcohol, and oral hygiene was also considered. RESULTS: The prevalence of Herpesviridae family virus DNA was 6% for the periodontal healthy group and 60% for the periodontitis group (roughly 60% on periodontitis stages II, III, and IV, p <0.001; and twofold increase in moderate and rapid progression grades compared with the slow progression grade, p <0.001). HSV1 DNA was prevalent in all periodontitis stages and grades. HSV 2, EBV, and CMV DNA had increasing prevalence rates in more severe stages (stages III and IV, p <0.001); while considering periodontitis grade, HSV2 (p = 0.001), CMV (p = 0.019) and EBV (p <0.001) DNA were prevalent only in grades B and C, with EBV DNA registering a marked prevalence in grade C. CONCLUSION: A significant different distribution of Herpesviridae virus DNA per each stage of disease was registered.

Revisiting Oral Antiseptics, Microorganism Targets and Effectiveness.

A good oral health status is mostly dependent on good oral hygiene habits, which knowingly impacts systemic health. Although controversial, chemical oral antiseptics can be useful in adjunct use to mechanical dental plaque control techniques in the prevention and management of local and overall health and well-being. This review aims to revisit, gather and update evidence-based clinical indications for the use of the most popular oral antiseptics, considering different types, microorganism targets and effectiveness in order to establish updated clinical recommendations.

Data of Nebivolol on oxidative stress parameters in hypertensive patients.

Oxidative stress is a key feature in hypertension, since reactive oxygen species are involved in all stages of cardiovascular diseases. Saliva is a body fluid that can be used to investigate alterations in the oxidative system with several specific advantages over blood. Nebivolol is a third-generation selective ß1-adrenergic receptor antagonist that promotes vasodilation and has been shown to reduce oxidative stress in pre-clinical and clinical studies. The use of Nebivolol in different periods of treatment demonstrated that it is an efficient anti-hypertensive drug. We evaluated the oxidative stress biomarkers and the enzymatic and non-enzymatic antioxidant systems in saliva of hypertensive patients before and after the use of anti-hypertensive therapeutic doses of Nebivolol, since saliva can be used as an auxiliary tool to analyze parameters of oxidative stress.

Potent and broadly reactive HIV-2 neutralizing antibodies elicited by a vaccinia virus vector prime-C2V3C3 polypeptide boost immunization strategy.

Human immunodeficiency virus type 2 (HIV-2) infection affects about 1 to 2 million individuals, the majority living in West Africa, Europe, and India. As for HIV-1, new strategies for the prevention of HIV-2 infection are needed. Our aim was to produce new vaccine immunogens that elicit the production of broadly reactive HIV-2 neutralizing antibodies (NAbs). Native and truncated envelope proteins from the reference HIV-2ALI isolate were expressed in vaccinia virus or in bacteria. This source isolate was used due to its unique phenotype combining CD4 independence and CCR5 usage. NAbs were not elicited in BALB/c mice by single immunization with a truncated and fully glycosylated envelope gp125 (gp125t) or a recombinant polypeptide comprising the C2, V3, and C3 envelope regions (rpC2-C3). A strong and broad NAb response was, however, elicited in mice primed with gp125t expressed in vaccinia virus and boosted with rpC2-C3. Serum from these animals potently neutralized (median 50% neutralizing titer, 3,200) six of six highly divergent primary HIV-2 isolates. Coreceptor usage and the V3 sequence of NAb-sensitive isolates were similar to that of the vaccinating immunogen (HIV-2ALI). In contrast, NAbs were not reactive on three X4 isolates that displayed major changes in V3 loop sequence and structure. Collectively, our findings demonstrate that broadly reactive HIV-2 NAbs can be elicited by using a vaccinia virus vector-prime/rpC2-C3-boost immunization strategy and suggest a potential relationship between escape to neutralization and cell tropism.

HIV-2 genetic evolution in patients with advanced disease is faster than that in matched HIV-1 patients.

The objective of this study was to estimate and compare the evolutionary rates of HIV-2 and HIV-1. Two HIV-2 data sets from patients with advanced disease were compared to matched HIV-1 data sets. The estimated mean evolutionary rate of HIV-2 was significantly higher than the estimated rate of HIV-1, both in the gp125 and in the V3 region of the env gene. In addition, the rate of synonymous substitutions in gp125 was significantly higher for HIV-2 than for HIV-1, possibly indicating a shorter generation time or higher mutation rate of HIV-2. Thus, the lower virulence of HIV-2 does not appear to translate into a lower rate of evolution.

Spiro-ß-lactam BSS-730A Displays Potent Activity against HIV and Plasmodium.

The high burden of malaria and HIV/AIDS prevents economic and social progress in developing countries. A continuing need exists for development of novel drugs and treatment regimens for both diseases in order to address the tolerability and long-term safety concerns associated with current treatment options and the emergence of drug resistance. We describe new spiro-ß-lactam derivatives with potent (nM) activity against HIV and Plasmodium and no activity against bacteria and yeast. The best performing molecule of the series, BSS-730A, inhibited both HIV-1 and HIV-2 replication with an IC50 of 13 ± 9.59 nM and P. berghei hepatic infection with an IC50 of 0.55 ± 0.14 µM with a clear impact on parasite development. BSS-730A was also active against the erythrocytic stages of P. falciparum, with an estimated IC50 of 0.43 ± 0.04 µM. Time-of-addition studies showed that BSS-730A potentially affects all stages of the HIV replicative cycle, suggesting a complex mechanism of action. BSS-730A was active against multidrug-resistant HIV isolates, with a median 2.4-fold higher IC50 relative to control isolates. BSS-730A was equally active against R5 and X4 HIV isolates and displayed strong synergism with the entry inhibitor AMD3100. BSS-730A is a promising candidate for development as a potential therapeutic and/or prophylactic agent against HIV and Plasmodium.

High Hydrostatic Pressure as Sterilization Method for Drug-Loaded Intraocular Lenses.

Sterilization is a key step in the manufacturing of drug-loaded intraocular lenses (IOLs). Two of the most used methods to sterilize commercial IOLs are steam heat and gamma radiation. However, when the IOLs are loaded with drugs, the adequacy of those methods must be questioned because sterilization may affect the activity of the drugs and/or the drug release. Recently, high hydrostatic pressure (HHP), which is increasingly used in the food industry, has been applied in the sterilization of gels for medical applications. The objective of this work was to assess the performance of HHP in the sterilization of a commercial acrylic material used for the production of IOLs, both without and with loaded drugs. Bare samples and samples loaded with an antibiotic and two anti-inflammatories were tested, and the results were compared to those obtained with conventional sterilization methods. HHP not only sterilized highly contaminated samples but also enhanced drug loading and did not affect significantly the hydrogel properties. Gamma radiation degraded the drugs in solution; thus, it is adequate only for dry sample sterilization. Steam heat did not affect the release profiles but cannot be applied to temperature-sensitive drugs. We concluded that HHP may advantageously substitute steam heat and gamma radiation in the sterilization of drug-loaded IOLs.

The role of the humoral immune response in the molecular evolution of the envelope C2, V3 and C3 regions in chronically HIV-2 infected patients.

BACKGROUND: This study was designed to investigate, for the first time, the short-term molecular evolution of the HIV-2 C2, V3 and C3 envelope regions and its association with the immune response. Clonal sequences of the env C2V3C3 region were obtained from a cohort of eighteen HIV-2 chronically infected patients followed prospectively during 2-4 years. Genetic diversity, divergence, positive selection and glycosylation in the C2V3C3 region were analysed as a function of the number of CD4+ T cells and the anti-C2V3C3 IgG and IgA antibody reactivity RESULTS: The mean intra-host nucleotide diversity was 2.1% (SD, 1.1%), increasing along the course of infection in most patients. Diversity at the amino acid level was significantly lower for the V3 region and higher for the C2 region. The average divergence rate was 0.014 substitutions/site/year, which is similar to that reported in chronic HIV-1 infection. The number and position of positively selected sites was highly variable, except for codons 267 and 270 in C2 that were under strong and persistent positive selection in most patients. N-glycosylation sites located in C2 and V3 were conserved in all patients along the course of infection. Intra-host variation of C2V3C3-specific IgG response over time was inversely associated with the variation in nucleotide and amino acid diversity of the C2V3C3 region. Variation of the C2V3C3-specific IgA response was inversely associated with variation in the number of N-glycosylation sites. CONCLUSION: The evolutionary dynamics of HIV-2 envelope during chronic aviremic infection is similar to HIV-1 implying that the virus should be actively replicating in cellular compartments. Convergent evolution of N-glycosylation in C2 and V3, and the limited diversification of V3, indicates that there are important functional constraints to the potential diversity of the HIV-2 envelope. C2V3C3-specific IgG antibodies are effective at reducing viral population size limiting the number of virus escape mutants. The C3 region seems to be a target for IgA antibodies and increasing N-linked glycosylation may prevent HIV-2 envelope recognition by these antibodies. Our results provide new insights into the biology of HIV-2 and its relation with the human host and may have important implications for vaccine design.

Synonymous substitution rates predict HIV disease progression as a result of underlying replication dynamics.

Upon HIV transmission, some patients develop AIDS in only a few months, while others remain disease free for 20 or more years. This variation in the rate of disease progression is poorly understood and has been attributed to host genetics, host immune responses, co-infection, viral genetics, and adaptation. Here, we develop a new "relaxed-clock" phylogenetic method to estimate absolute rates of synonymous and nonsynonymous substitution through time. We identify an unexpected association between the synonymous substitution rate of HIV and disease progression parameters. Since immune activation is the major determinant of HIV disease progression, we propose that this process can also determine viral generation times, by creating favourable conditions for HIV replication. These conclusions may apply more generally to HIV evolution, since we also observed an overall low synonymous substitution rate for HIV-2, which is known to be less pathogenic than HIV-1 and capable of tempering the detrimental effects of immune activation. Humoral immune responses, on the other hand, are the major determinant of nonsynonymous rate changes through time in the envelope gene, and our relaxed-clock estimates support a decrease in selective pressure as a consequence of immune system collapse.

Inhibitory activity of a green and black tea blend on Streptococcus mutans.

Through the years, tea consumption has been associated with good health, and some publications are related to oral health. The bioactive components of green tea are thought to be able to influence the process of caries formation through inhibition of proliferation of the streptococcal agent, interference with the process of bacterial adhesion to tooth enamel, and inhibition of glucosyl transferase and amylase; however, little is known about black tea and oral health. The aim of the present in-vitro study was to determine the inhibitory activity of a novel, patent-pending and proprietary blend of green and black tea aqueous extracts on Streptococcus mutans, a bacterium widely associated with plaque development and tooth decay. A minimum inhibitory concentration (MIC) of 12.5 mg/mL and a minimum bactericidal concentration (MBC) of 12.5 mg/mL was established against S. mutans, meaning that at concentrations of 12.5 mg/mL and higher, the proprietary tea blend is effective against the growth of S. mutans. This MIC concentration is lower than the ones reported in the literature for alcoholic black tea and green tea extracts tested separately. As a promising natural ingredient for oral health, this finding is a good indicator for the use of this proprietary blend of black and green tea water extracts.

Correction: Evaluation of the fusion inhibitor P3 peptide as a potential microbicide to prevent HIV transmission in women.

[This corrects the article DOI: 10.1371/journal.pone.0195744.].

Evaluation of the fusion inhibitor P3 peptide as a potential microbicide to prevent HIV transmission in women.

Microbicides are an important strategy for preventing the sexual transmission of HIV but, so far, the most advanced tenofovir-based microbicides have had modest efficacy. This has been related to adherence problems and high prevalence of tenofovir-resistant HIV-1 strains. P3 is a new peptide with potent activity against HIV that may be a good microbicide candidate. In this work P3 was formulated in a gel of hydroxyethyl cellulose and its activity, stability and safety profile in Balb/c mice were evaluated. HIV infection was fully blocked by a 1.5% gel containing P3 at the IC90 (366.4 nM) concentration. The antiviral activity did not change at 4°C during 4 months and at 25, 37 and 65°C for 1 week. P3 was stable and fully functional at acidic pH up to 24h, under different concentrations of hydrogen peroxide and in the presence of genital fluids up to 48h. P3 had no antibacterial activity and did not affect sperm motility and vitality. Finally, P3 didn't cause significant alterations in the vaginal epithelium of Balb/c mice at 0.06 (456.8 µM) and 0.2 mg/day (1522.7 µM) doses. These findings indicate that P3 is an excellent candidate for further development as a microbicide gel for the prevention of HIV transmission in women.

Evidence for negative selective pressure in HIV-2 evolution in vivo.

HIV-2 sequence divergence and evolution in vivo has not been well characterized so far. To investigate the extent of HIV-2 genetic diversity and better understand how HIV-2 evolves in vivo, env C2-C3 nucleotide sequences were obtained from the plasma and PBMCs virus populations of four HIV-2 patients with different infection periods. Phylogenetic analysis showed that three patients were infected with subtype A HIV-2 and the remaining patient was infected with a divergent HIV-2 that could not be genotyped. Virus populations from the plasma and PBMCs clustered together in all patients suggesting that there is continuous and unrestricted virus flow between plasma and PBMCs. HIV-2 genetic diversity was not correlated with CD4+ cell counts and plasma viral load. There was a direct association between the period of infection and genetic divergence of virus populations both in the env C2-C3 and V3 regions such that higher genetic diversity was observed in long-term infected patients. In three patients, the average frequency of synonymous substitutions (dS) was significantly higher than the nonsynonymous substitutions (dN) whereas in the fourth patient the dN/dS ratio approached the unity. These data demonstrate that negative selective pressure determines the evolution of the HIV-2 env C2-C3 region in vivo. Our results suggest that throughout HIV-2 infection low virus adaptation to strong selective pressures (e.g. immune pressure) promotes the predominance of a few optimally adapted forms.

Phylogenetic demonstration of two cases of perinatal human immunodeficiency virus type 2 infection diagnosed in adulthood.

HIV-2 infection was diagnosed in two patients 15 and 24 years of age and, thereafter, in their mothers. Epidemiological data suggested that vertical transmission was the most probable mode of infection in both patients (Mota-Miranda A, et al.: AIDS 2001;15:2460-2461). Phylogenetic analysis of env C2-C3 sequences from the patients and their mothers was used in an attempt to confirm or exclude the events of perinatal HIV-2 transmission. Sequences from each putative transmission pair formed monophyletic clusters in phylogenetic analysis, a clear indication of common ancestry. Interpatient nucleotide distances increased with the period of infection being consistent with long-term infection. In conclusion, the results are consistent with an epidemiological linkage between the viruses infecting each mother-child pair and support the occurrence of perinatal HIV-2 infection in both cases. Application of similar phylogeny methods to other suspected transmission cases may permit a better understanding of the epidemiology and molecular evolution of HIV-2.