SARS-CoV-2 shedding, infectivity, and evolution in an immunocompromised adult patient.

This study aimed to provide further insight into the evolutionary dynamics of SARS-CoV-2 by analyzing the case of a 40-year-old man who had previously undergone autologous hematopoietic stem cell transplantation due to a diffuse large B-cell lymphoma. He developed a persistent SARS-CoV-2 infection lasting at least 218 days and did not manifest a humoral immune response to the virus during this follow-up period. Whole-genome sequencing and viral cultures confirmed a persistent infection with a replication-positive virus that had undergone genetic variation for at least 196 days after symptom onset.

SARS-CoV-2 shedding, infectivity, and evolution in an immunocompromised adult patient

ABSTRACT This study aimed to provide further insight into the evolutionary dynamics of SARS-CoV-2 by analyzing the case of a 40-year-old man who had previously undergone autologous hematopoietic stem cell transplantation due to a diffuse large B-cell lymphoma. He developed a persistent SARS-CoV-2 infection lasting at least 218 days and did not manifest a humoral immune response to the virus during this follow-up period. Whole-genome sequencing and viral cultures confirmed a persistent infection with a replication-positive virus that had undergone genetic variation for at least 196 days after symptom onset.

Characterization of Torquetenovirus in amniotic fluid at the time of in utero fetal surgery: correlation with early premature delivery and respiratory distress.

Torquetenovirus (TTV) is a commensal virus present in many healthy individuals. Although considered to be non-pathogenic, its presence and titer have been shown to be indicative of altered immune status in individuals with chronic infections or following allogeneic transplantations. We evaluated if TTV was present in amniotic fluid (AF) at the time of in utero surgery to correct a fetal neurological defect, and whether its detection was predictive of adverse post-surgical parameters. AF was collected from 27 women by needle aspiration prior to a uterine incision. TTV titer in the AF was measured by isolation of viral DNA followed by gene amplification and analysis. The TTV genomes were further characterized and sequenced by metagenomics. Pregnancy outcome parameters were subsequently obtained by chart review. Three of the AFs (11.1%) were positive for TTV at 3.36, 4.16, and 4.19 log10 copies/mL. Analysis of their genomes revealed DNA sequences similar to previously identified TTV isolates. Mean gestational age at delivery was >2 weeks earlier (32.5 vs. 34.6 weeks) and the prevalence of respiratory distress was greater (100% vs. 20.8%) in the TTV-positive pregnancies. TTV detection in AF prior to intrauterine surgery may indicate elevated post-surgical risk for earlier delivery and newborn respiratory distress.

SARS-CoV-2 Detection and Culture in Different Biological Specimens from Immunocompetent and Immunosuppressed COVID-19 Patients Infected with Two Different Viral Strains.

Introduction-The dynamics of SARS-CoV-2 shedding and replication in humans remain incompletely understood. Methods-We analyzed SARS-CoV-2 shedding from multiple sites in individuals with an acute COVID-19 infection by weekly sampling for five weeks in 98 immunocompetent and 25 immunosuppressed individuals. Samples and culture supernatants were tested via RT-PCR for SARS-CoV-2 to determine viral clearance rates and in vitro replication. Results-A total of 2447 clinical specimens were evaluated, including 557 nasopharyngeal swabs, 527 saliva samples, 464 urine specimens, 437 anal swabs and 462 blood samples. The SARS-CoV-2 genome sequences at each site were classified as belonging to the B.1.128 (ancestral strain) or Gamma lineage. SARS-CoV-2 detection was highest in nasopharyngeal swabs regardless of the virus strain involved or the immune status of infected individuals. The duration of viral shedding varied between clinical specimens and individual patients. Prolonged shedding of potentially infectious virus varied from 10 days up to 191 days, and primarily occurred in immunosuppressed individuals. Virus was isolated in culture from 18 nasal swab or saliva samples collected 10 or more days after onset of disease. Conclusions-Our findings indicate that persistent SARS-CoV-2 shedding may occur in both competent or immunosuppressed individuals, at multiple clinical sites and in a minority of subjects is capable of in vitro replication.

Torquetenovirus in saliva: A potential biomarker for SARS-CoV-2 infection?

Torquetenovirus (TTV) is present in biological fluids from healthy individuals and measurement of its titer is used to assess immune status in individuals with chronic infections and after transplants. We assessed if the titer of TTV in saliva varied with the presence of SARS-CoV-2 in the nasopharynx and could be a marker of COVID-19 status. Saliva from 91 individuals positive for SARS-CoV-2 in nasal-oropharyngeal samples, and from 126 individuals who were SARS-CoV-2-negative, all with mild respiratory symptoms, were analyzed. Both groups were similar in age, gender, symptom duration and time after symptom initiation when saliva was collected. Titers of TTV and SARS-CoV-2 were assessed by gene amplification. Loss of smell (p = 0.0001) and fever (p = 0.0186) were more prevalent in SARS-CoV-2-positive individuals, while sore throat (p = 0.0001), fatigue (p = 0.0037) and diarrhea (p = 0.0475) were more frequent in the SARS-CoV-2 negative group. The saliva TTV and nasal-oropharyngeal SARS-CoV-2 titers were correlated (p = 0.0085). The TTV level decreased as symptoms resolved in the SARS-CoV-2 infected group (p = 0.0285) but remained unchanged in the SARS-CoV-2 negative controls. In SARS-CoV-2 positive subjects who provided 2-4 saliva samples and in which TTV was initially present, the TTV titer always decreased over time as symptoms resolved. We propose that sequential TTV measurement in saliva is potentially useful to assess the likelihood of symptom resolution in SARS-CoV-2-positive individuals and to predict prognosis.

Torquetenovirus Titer in Vaginal Secretions from Pregnant and Postpartum Women: Association with Absence of Lactobacillus crispatus and Levels of Lactic Acid and Matrix Metalloproteinase-8.

Vaginal samples from women with term deliveries were tested for torquetenovirus (TTV) by gene amplification, matrix metalloproteinase (MMP)-8 and D- and L-lactic acid by ELISA, and microbiome composition by analysis of the bacterial 16S ribosomal RNA gene. TTV was detected in 43.2%, 31.5%, and 41.4% of first trimester, third trimester, and postpartum samples, respectively. The viral titer was higher in postpartum than in the first (p = 0.0018) or third (p = 0.0013) trimester. The mean gestational age at delivery was lower in women positive for TTV in their first trimester (p = 0.0358). In the first and third trimester, the MMP-8 level was higher if TTV was also present (p < 0.0091). The D-lactic acid level was lower in first trimester samples if TTV was present (p = 0.0334). Lactobacillus crispatus dominance in first and third trimester samples was higher when TTV was absent (p < 0.0033). We conclude that TTV is present in the vagina in many women with normal pregnancy outcomes and that its occurrence is associated with a lack of L. crispatus dominance, an increase in vaginal MMP-8 and a decrease in D-lactic acid.

Influenza A and B in a cohort of outpatient children and adolescent with influenza like-illness during two consecutive influenza seasons

ABSTRACT Introduction Influenza is an important cause of morbimortality worldwide. Although people at the extremes of age have a greater risk of complications, influenza has been more frequently investigated in the elderly than in children, and inpatients than outpatients. Yearly vaccination with trivalent or quadrivalent vaccines is the main strategy to control influenza. Objectives Determine the clinical and molecular characteristics of influenza A and B infections in children and adolescents with influenza-like illness (ILI). Methods: A cohort of outpatient children and adolescents with ILI was followed for 20 months. Influenza was diagnosed with commercial multiplex PCR platforms. Results: 179 patients had 277 episodes of ILI, being 79 episodes of influenza A and 20 episodes of influenza B. Influenza A and B cases were mild and had similar presentation. Phylogenetic tree of influenza B viruses showed that 91.6% belonged to the B/Yamagata lineage, which is not included in trivalent vaccines. Conclusions: Influenza A and B are often detected in children and adolescents with ILI episodes, with similar and mild presentation in outpatients. The mismatch between the circulating influenza viruses and the trivalent vaccine offered in Brazil may have contributed to the high frequency of influenza A and B in this population.

Influenza A and B in a cohort of outpatient children and adolescent with influenza like-illness during two consecutive influenza seasons.

INTRODUCTION: Influenza is an important cause of morbimortality worldwide. Although people at the extremes of age have a greater risk of complications, influenza has been more frequently investigated in the elderly than in children, and inpatients than outpatients. Yearly vaccination with trivalent or quadrivalent vaccines is the main strategy to control influenza. OBJECTIVES: Determine the clinical and molecular characteristics of influenza A and B infections in children and adolescents with influenza-like illness (ILI). METHODS: A cohort of outpatient children and adolescents with ILI was followed for 20 months. Influenza was diagnosed with commercial multiplex PCR platforms. RESULTS: 179 patients had 277 episodes of ILI, being 79 episodes of influenza A and 20 episodes of influenza B. Influenza A and B cases were mild and had similar presentation. Phylogenetic tree of influenza B viruses showed that 91.6% belonged to the B/Yamagata lineage, which is not included in trivalent vaccines. CONCLUSIONS: Influenza A and B are often detected in children and adolescents with ILI episodes, with similar and mild presentation in outpatients. The mismatch between the circulating influenza viruses and the trivalent vaccine offered in Brazil may have contributed to the high frequency of influenza A and B in this population.

Prospective study of human herpesvirus 8 oral shedding, viremia, and serological status among human immunodeficiency virus seropositive and seronegative individuals in Sao Paulo, Brazil.

Human herpesvirus 8 (HHV-8) is a gamma-herpesvirus and etiological agent of all forms of Kaposi sarcoma (KS). Saliva may play an important role in HHV-8 transmission in specific populations. Little is known about HHV-8 oral shedding pattern and the possible correlation with the HHV-8 serological profile and viremia. A prospective study was conducted of HHV-8 salivary excretion among human immunodeficiency virus HIV-seronegative (n = 47) and -seropositive (n = 44) homosexual men and HIV-seropositive women (n = 32) over a 6-month period with monthly HHV-8 serologies (immunofluorescence assays to identify antibodies to latent and lytic HHV-8 viral proteins, and a whole-virus HHV-8 enzyme-linked immunosorbent assay [ELISA]), monthly HHV-8 DNA serum/plasma detection, and daily self-collected oral rinses for HHV-8-DNA detection using real-time polymerase chain reaction. HHV-8 seropositivity was 51.1%, 63.6%, and 37.5%, in the three studied groups. There was no case of HHV-8 DNA detection in serum/plasma. Intermittent detection of oral HHV-8 DNA was observed during 5.1% (110/2,160) of visits among 28% (18/64) of HHV-8-seropositive individuals, all of whom were males and HHV-8 ELISA seropositive. In immunologically controlled populations of Brazil, HHV-8 oral shedding was limited to HHV-8-seropositive men, occurred infrequently and intermittently, and was not linked to HHV-8 viremia, suggesting a limited potential for oral or blood transmission.

Fatal Human herpesvirus 1 (HHV-1) infection in captive marmosets (Callithrix jacchus and Callithrix penicillata) in Brazil: clinical and pathological characterization / Infecção fatal por Herpesvirus simplex Tipo 1 (HHV-1) em saguis de cativeiro (Callithrix jacchus and Callithrix penicillata) no Brasil: caracterização clínica e patológica

Fatal Human herpesvirus 1 (HHV-1) was diagnosed in 12 captive marmosets (Callithrix jacchus and Callithrix penicillata) from metropolitan region of São Paulo, São Paulo State. Clinical signs were variable among the cases, but most affected marmosets presented signs associated with viral epithelial replication: oral, lingual and facial skin ulcers and hypersalivation, and viral replication in the central nervous system: prostration, seizure and aggressive behavior. Consistent microscopic findings were diffuse mild to severe nonsuppurative necrotizing meningoencephalitis with gliosis, vasculitis and neuronal necrosis. Additionally, in the brain, oral cavity, skin, adrenal gland and myoenteric plexus intranuclear inclusion bodies were present. Immunohistochemistry confirmed the presence of the HHV-1 antigen in association with lesions in the brain, oral and lingual mucosa, facial skin, adrenal gland and myoenteric plexus. HHV-1-specific polymerase chain reaction (PCR) analysis of the brain was carried out and the virus was detected in 7/8 infected marmosets. It is concluded that HHV-1 causes widespread fatal infection in marmosets.(AU)

Infecção fatal por Herpesvirus simplex Tipo 1 (HHV-1) foi diagnosticada em 12 saguis de cativeiro (Callithrix jacchus e Callithrix penicillata) provenientes da região metropolitana de São Paulo, Estado de São Paulo. Os sinais clínicos foram variáveis entres os casos, no entanto, a maioria dos saguis afetados apresentavam sinais associados à replicação viral em epitélios: úlceras na cavidade oral, língua e pele da face e hipersalivação; e no sistema nervoso central: prostração, convulsão e comportamento agressivo. Histologicamente, o principal achado foi meningoencefalite necrosante não supurativa difusa, leve a acentuada com gliose, vasculite e necrose neuronal. Inclusões intranucleares também foram observadas em encéfalo, cavidade oral, pele, glândula adrenal e plexo mioentérico. A imuno-histoquímica anti-HHV-1 confirmou a presença do antígeno viral em associação às lesões em encéfalo, mucosa oral e lingual, pele da face, glândula adrenal e plexo mioentérico. Em 7/8 saguis infectados foi detectada a presença de HHV-1 por reação em cadeia da polimerase (PCR) a partir de amostras de encéfalo. Conclui-se que HHV-1 causa uma infecção disseminada e fatal em saguis.(AU)

Transmission of human herpesvirus type 8 infection within families in american indigenous populations from the Brazilian Amazon.

BACKGROUND: The intrafamilial dynamics of endemic infection with human herpesvirus type 8 (HHV-8) in Amerindian populations is unknown. METHODS: Serum samples were obtained from 517 Amerindians and tested for HHV-8 anti-latent nuclear antigen (anti-LANA) and antilytic antibodies by immunofluorescence assays. Logistic regression and mixed logistic models were used to estimate the odds of being HHV-8 seropositive among intrafamilial pairs. RESULTS: HHV-8 seroprevalence by either assay was 75.4% (95% confidence interval [CI]: 71.5%-79.1%), and it was age-dependent (P(trend) < .001). Familial dependence in HHV-8 seroprevalence by either assay was found between mother-offspring (odds ratio [OR], 5.44; 95% CI: 1.62-18.28) and siblings aged ≥10 years (OR 4.42, 95% CI: 1.70-11.45) or siblings in close age range (<5 years difference) (OR 3.37, 95% CI: 1.21-9.40), or in families with large (>4) number of siblings (OR, 3.20, 95% CI: 1.33-7.67). In separate analyses by serological assay, there was strong dependence in mother-offspring (OR 8.94, 95% CI: 2.94-27.23) and sibling pairs aged ≥10 years (OR, 11.91, 95% CI: 2.23-63.64) measured by LANA but not lytic antibodies. CONCLUSIONS: This pattern of familial dependence suggests that, in this endemic population, HHV-8 transmission mainly occurs from mother to offspring and between close siblings during early childhood, probably via saliva. The mother to offspring dependence was derived chiefly from anti-LANA antibodies.

Non-detection of human herpesvirus 8 (HHV-8) DNA in HHV-8-seropositive blood donors from three Brazilian regions.

Human herpesvirus 8 (HHV-8), also known as Kaposi's sarcoma-associated herpesvirus (KSHV), is the etiologic agent of all forms of Kaposi's sarcoma, primary effusion lymphoma and the plasmablastic cell variant of multicentric Castleman disease. In endemic areas of sub-Saharan Africa, blood transfusions have been associated with a substantial risk of HHV-8 transmission. By contrast, several studies among healthy blood donors from North America have failed to detect HHV-8 DNA in samples of seropositive individuals. In this study, using a real-time PCR assay, we investigated the presence of HHV-8 DNA in whole-blood samples of 803 HHV-8 blood donors from three Brazilian states (São Paulo, Amazon, Bahia) who tested positive for HHV-8 antibodies, in a previous multicenter study. HHV-8 DNA was not detected in any sample. Our findings do not support the introduction of routine HHV-8 screening among healthy blood donors in Brazil. (WC = 140).

Prevalence of, and risk factors for Kaposi's sarcoma-associated herpesvirus infection among blood donors in Brazil: a multi-center serosurvey.

Kaposi's sarcoma-associated herpesvirus (KSHV) is endemic in the Amazon and rare in southern regions of Brazil. However, geographical distribution and epidemiological correlates of infection in this large country are still poorly defined. To estimate the seroprevalence of, and risk factors for, KSHV infection in Brazil, a multi-center study was conducted among 3,493 first-time voluntary unpaid blood donors from Salvador, Sao Paulo and Manaus. Antibodies against KSHV were detected using a whole-virus ELISA validated prior to the serosurvey. Antibodies against the latency-associated nuclear antigen (LANA) were detected by immuno-fluorescence assay (IFA) among ELISA-positive sera and a random sample of ELISA-negative sera. Overall, seroprevalence of KSHV by whole-virus ELISA was 21.7% (95% confidence interval (CI): 20-23.4%) in men and 31.7% (95% CI: 29-34.3%) in women (P<0.0001). KSHV antibodies were detected by IFA-LANA in 3% (95% CI: 2-4.3%) of 867 ELISA-positive samples and in none of 365 randomly selected ELISA-negative samples. In multivariate analysis, KSHV seroprevalence by whole-virus ELISA was independently associated with female sex (odds ratio [OR]=1.6, 95% CI: 1.4-1.9); residence in the Amazon (OR=1.4, 95% CI: 1.2-1.8; compared to Salvador); Caucasian ethnicity (OR=1.3, 95% CI: 1.1-1.6) and herpes simplex virus type 2 (HSV-2) infection (OR=1.3, 95% CI: 1.1-1.6). KSHV seroprevalence did not significantly increase with age, nor was it associated with self-reported sexual behavior. KSHV seroprevalence is high among Brazilian blood donors, particularly from the Amazon region. This study supports the co-existence of sexual and non-sexual routes of KSHV transmission in this population.

Seroreactivity to Kaposi's sarcoma-associated herpesvirus (human herpesvirus 8) latent nuclear antigen in AIDS-associated Kaposi's sarcoma patients depends on CD4+ T-cell count.

In AIDS/Kaposi's sarcoma (KS) patients, the sensitivity of immunofluorescence assays for detecting antibodies against latent nuclear antigen ranges from 52% to 93%. However, in classic and African KS, sensitivities above 90% have been reported systematically. This study evaluates whether CD4+ T-cell count affects seroreactivity to KSHV LANA and to lytic antigens in AIDS/KS patients. Kaposi's sarcoma-associated herpesvirus (KSHV) latent (IFA-LANA) and lytic (IFA-Lytic and ORF65/K8.1 EIA) antibodies were screened in 184 consecutive samples taken from 36 AIDS/KS patients grouped according to their CD4+ counts as follows: <100 (group A), 100-300 (group B), and >300 (group C) cells/mm(3). At enrollment, the immunofluorescence assay for the detection of antibodies against latent nuclear antigen (IFA-LANA) was positive in 3/11(27.2%) group A patients, in 10/11 (90.9%) group B patients, and in 14/14 (100%) group C patients (P < 0.01). Seropositivity to lytic antigens did not differ according to CD4+ T-cell count. Considering IFA-Lytic and ORF65/K8.1 EIA, seropositivity for lytic antigens was 100% in all three patient groups. In patients whose CD4+ count improved during follow-up, IFA-LANA seroconversion occurred; unstable counts resulted in a decrease in LANA antibody titers while the persistence of high counts resulted in unchanged, elevated antibody titers. In conclusion, LANA seroreactivity in AIDS/KS patients, as assessed by an immunofluorescence assay, depends on CD4+ T-cell count, rendering this evaluation important in the interpretation of seroepidemiological studies of KSHV infection in AIDS patients. To evaluate future serological tests based on latency-associated antigens, the selection of sera from KS patients with CD4+ cell count >300 cells/mm(3) as a positive gold standard is recommended.

Human herpesvirus-8 infection and oral shedding in Amerindian and non-Amerindian populations in the Brazilian Amazon region.

BACKGROUND: Human herpesvirus type 8 (HHV-8) is hyperendemic in Amerindian populations, but its modes of transmission are unknown. METHODS: Antibodies against either HHV-8 lytic antigen or HHV-8 latency-associated nuclear antigen (LANA) were detected, by immunofluorescence assays, in 339 Amerindians and 181 non-Amerindians from the Brazilian Amazon. Serological markers of oro-fecal (hepatitis A), parenteral (hepatitis B and C), and sexual (herpes simplex virus type 2 and syphilis) transmission were measured by specific ELISAs. Salivary HHV-8 DNA was detected by use of a nested polymerase chain reaction assay and was sequenced. RESULTS: Antibodies against either lytic antigen or LANA were detected in 79.1% of Amerindians and in 6.1% of non-Amerindians (adjusted seroprevalence ratio [SR], 12.63 [95% confidence interval {CI}, 7.1-22.4]; P<.0001). HHV-8 seroprevalence increased with age among Amerindians (P(Trend) < .001) and already had high prevalence in childhood but was not sex specific in either population. The 2 populations did not differ in seroprevalence of oro-fecal or parenteral markers, but seroprevalence of markers of sexual transmission was lower among Amerindians. HHV-8 DNA in saliva was detected in 47 (23.7%) of 198 HHV-8 seropositive Amerindians. Detection of HHV-8 DNA decreased with age (P(Trend) < .04) and was more common in men (SR, 2.14 [95% CI, 1.3-3.5]; P=.003). A total of 36 (76.6%) of the 47 saliva HHV-8 DNA samples were sequenced, and all clustered as subtype E. CONCLUSION: The data support the hypothesis of early acquisition and horizontal transmission, via saliva, of HHV-8 subtype E in Amerindian populations.

CCR5 genotypes and progression to HIV disease in perinatally infected children.

The CCR5 molecule, a chemokine receptor, is the most important co-receptor for macrophage-tropic HIV-1. A 32-bp deletion in the gene encoding CCR5 (CCR5-del32) confers nearly complete resistance to HIV-1 infection in homozygotes, and slows the rate of progression to AIDS in heterozygous adults. The aim of this study was to describe the CCR5 genotypes and the characteristics of HIV disease progression in perinatally infected children. From a total of 51 children analyzed for the CCR5-del32 mutation, 18 (35%) were considered to be rapid progressors, 28 (55%) were moderate progressors and 5 (10%) were slow progressors. A portion of the CCR5 gene was amplified by PCR from genomic DNA followed by agarose gel electrophoresis. Forty-nine children (96%) carried the homozygous wild type genotype for CCR5 while 2 (4%) carried the heterozygous wt/del32 genotype. In the population studied, the CCR5 genotype was unable to account for the differences in pattern of the disease progression among the three groups (rapid, moderate and slow progressors), and the allele frequency of CCR5-del32 was too low to allow statistical comparisons with adequate resolving power. Studies on larger populations may help to further elucidate the role of this allele and other host factors in the regulation of HIV-1 pathogenesis in children.

CCR5 genotypes and progression to HIV disease in perinatally infected children

The CCR5 molecule, a chemokine receptor, is the most important co-receptor for macrophage-tropic HIV-1. A 32-bp deletion in the gene encoding CCR5 (CCR5-del32) confers nearly complete resistance to HIV-1 infection in homozygotes, and slows the rate of progression to AIDS in heterozygous adults. The aim of this study was to describe the CCR5 genotypes and the characteristics of HIV disease progression in perinatally infected children. From a total of 51 children analyzed for the CCR5-del32 mutation, 18 (35 percent) were considered to be rapid progressors, 28 (55 percent) were moderate progressors and 5 (10 percent) were slow progressors. A portion of the CCR5 gene was amplified by PCR from genomic DNA followed by agarose gel electrophoresis. Forty-nine children (96 percent) carried the homozygous wild type genotype for CCR5 while 2 (4 percent) carried the heterozygous wt/del32 genotype. In the population studied, the CCR5 genotype was unable to account for the differences in pattern of the disease progression among the three groups (rapid, moderate and slow progressors), and the allele frequency of CCR5-del32 was too low to allow statistical comparisons with adequate resolving power. Studies on larger populations may help to further elucidate the role of this allele and other host factors in the regulation of HIV-1 pathogenesis in children.

Comparative study of Kaposi's sarcoma-associated herpesvirus serological assays using clinically and serologically defined reference standards and latent class analysis.

Accurate determination of infection with Kaposi's sarcoma-associated herpesvirus (KSHV) has been hindered by the lack of a "gold standard" for comparison of serological assays used to estimate KSHV prevalence in serosurveys conducted in different settings. We have evaluated the performance of five in-house (developed at University College London [UCL], United Kingdom, and at the virology laboratory of the Instituto de Medicine Tropical [IMT] in Sao Paulo, Brazil) and two commercial (ABI and DIAVIR) serological assays to detect antibodies to latency-associated nuclear antigen (LANA) and to lytic KSHV antigens. We used a variety of serum samples assembled to represent populations likely to be at high, intermediate, and low risk of KSHV infection in Brazil. Composite reference standard panels were prepared based on clinical and serological parameters, against which assay performances were assessed using conventional Bayesian statistics and latent class analysis (LCA). Against the clinical reference standard, in-house immunofluorescence assays to detect anti-LANA antibodies (IFA-LANA) produced at UCL and IMT had similar performances, with sensitivities of 61% (95% confidence interval [CI], 48% to 74%) and 72% (95% CI, 58% to 83%) and specificities of 99% (95% CI, 94% to 100%) and 100% (95% CI, 96% to 100%), respectively, and only the IMT IFA-LANA was included in LCA, together with the IMT IFA-lytic and four enzyme-linked immunosorbent assays (ELISAs). The LCA indicated that the IMT whole-virus ELISA performed best (sensitivity, 87% [95% CI, 81% to 91%]; and specificity, 100% [95% CI, 98% to 100%]), confirming the results obtained with the conventional statistical approach. Commercially available ELISA-based tests yielded the lowest specificities using a spectrum of serum samples. The evaluation of KSHV serological assays is warranted before planning serosurveys in various settings.

Analysis of HIV- type 1 protease and reverse transcriptase in Brazilian children failing highly active antiretroviral therapy (HAART).

The aim of this study was to evaluate the genotypic resistance profiles of HIV-1 in children failing highly active antiretroviral therapy (HAART). Forty-one children (median age = 67 months) receiving HAART were submitted to genotypic testing when virological failure was detected. cDNA was extracted from PBMCs and amplified by nested PCR for the reverse transcriptase and protease regions of the pol gene. Drug resistance genotypes were determined from DNA sequencing. According to the genotypic analysis, 12/36 (33.3%) and 6/36 (16.6%) children showed resistance and possible resistance, respectively, to ZDV; 5/36 (14%) and 4/36 (11.1%), respectively, showed resistance and possible resistance to ddI; 4/36 (11.1%) showed resistance to 3TC and D4T; and 3/36 (8.3%) showed resistance to Abacavir. A high percentage (54%) of children exhibited mutations conferring resistance to NNRTI class drugs. Respective rates of resistance and possible resistance to PIs were: RTV (12.2%, 7.3%); APV (2.4%, 12.1%); SQV(0%, 12.1%); IDV (14.6%, 4.9%), NFV (22%, 4.9%), LPV/RTV (2.4%, 12.1%). Overall, 37/41 (90%) children exhibited virus with mutations related to drug resistance, while 9% exhibited resistance to all three antiretroviral drug classes.

Analysis of HIV- type 1 protease and reverse transcriptase in Brazilian children failing highly active antiretroviral therapy (HAART)

O objetivo deste estudo foi avaliar o perfil de resistência genotípica do HIV-1 em crianças com falha terapêutica ao tratamento anti-retroviral (HAART). Quarenta e uma crianças (idade mediana = 67 meses) em uso de HAART foram submetidas ao teste de genotipagem no momento da detecção de falha ao tratamento. Foi realizada extração de cDNA de células periféricas mononucleares e amplificação do mesmo (regiões da transcriptase reversa e protease do gene pol) através de PCR-nested. O perfil genotípico foi determinado através do seqüenciamnto de nucleotídeos. De acordo com a análise genotípica, 12/36 (33,3%) e 6/36 (16,6%) crianças apresentaram, respectivamente, resistência e possível resistência ao AZT; 5/36 (14%) e 4/36 (11,1%), respectivamente, eram resistentes e possivelmente resistentes ao ddI; 4/36 %11,1%) apresentaram resistência ao 3TC e D4T, e 3/36 (8,3%) eram resistentes ao ABC. Uma alta porcentagem de crianças (54%) apresentou mutações relacionadas à resistência aos inibidores da trancriptase reversa não-análogos de nucleosídeos. As taxas de resistência e possível resistência aos inibidores da protease foram, respectivamente: RTV (12,2%; 7,3%); APV (2,4%; 12,1%); SQV (0%; 12,1%); IDV (14,6%; 4,9%); NFV (22%; 4,9%); LPV/RTV (2,4%; 12,1%). No total, 37/41 (90%) crianças apresentaram vírus com mutações relacionadas à resistência a alguma droga, sendo que 9% delas tinham vírus resistentes às três classes de drogas anti-retrovirais disponíveis.