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The city of Wuhan in China is the focus of global attention due to an outbreak of a febrile respiratory illness due to a coronavirus 2019-nCoV. In December 2019, there was an outbreak of pneumonia of unknown cause in Wuhan, Hubei province in China, with an epidemiological link to the Huanan Seafood Wholesale Market where there was also sale of live animals. Notification of the WHO on 31 Dec 2019 by the Chinese Health Authorities has prompted health authorities in Hong Kong, Macau, and Taiwan to step up border surveillance, and generated concern and fears that it could mark the emergence of a novel and serious threat to public health (WHO, 2020aWHO Emergencies preparedness, response. Pneumonia of unknown origin – China.Disease outbreak news. 2020https://www.who.int/csr/don/05-january-2020-pneumonia-of-unkown-cause-china/en/Google Scholar, Parr, 2020Parr J. Pneumonia in China: lack of information raises concerns among Hong Kong health workers.BMJ. 2020; 368 (Published 8 January 2020): m56https://doi.org/10.1136/bmj.m56Crossref PubMed Scopus (22) Google Scholar). The Chinese health authorities have taken prompt public health measures including intensive surveillance, epidemiological investigations, and closure of the market on 1 Jan 2020. SARS-CoV, MERS-CoV, avian influenza, influenza and other common respiratory viruses were ruled out. The Chinese scientists were able to isolate a 2019-nCoV from a patient within a short time on 7 Jan 2020 and perform genome sequencing of the 2019-nCoV. The genetic sequence of the 2019-nCoV has become available to the WHO on 12 Jan 2020 and this has facilitated the laboratories in different countries to produce specific diagnostic PCR tests for detecting the novel infection (WHO, 2020bWHO Emergencies preparedness, response. Pneumonia of unknown origin – China.Disease outbreak news. 2020https://www.who.int/csr/don/12-january-2020-novel-coronavirus-china/en/Google Scholar). The 2019-nCoV is a β CoV of group 2B with at least 70% similarity in genetic sequence to SARS-CoV and has been named 2019-nCoV by the WHO. SARS is a zoonosis caused by SARS-CoV, which first emerged in China in 2002 before spreading to 29 countries/regions in 2003 through a travel-related global outbreak with 8,098 cases with a case fatality rate of 9.6%. Nosocomial transmission of SARS-CoV was common while the primary reservoir was putatively bats, although unproven as the actual source and the intermediary source was civet cats in the wet markets in Guangdong (Hui and Zumla, 2019Hui D.S.C. Zumla A. Severe acute respiratory syndrome: historical, epidemiologic, and clinical features.Infect Dis Clin North Am. 2019; 33: 869-889Abstract Full Text Full Text PDF PubMed Scopus (357) Google Scholar). MERS is a novel lethal zoonotic disease of humans endemic to the Middle East, caused by MERS-CoV. Humans are thought to acquire MERS-CoV infection though contact with camels or camel products with a case fatality rate close to 35% while nosocomial transmission is also a hallmark (Azhar et al., 2019Azhar E.I. Hui D.S.C. Memish Z.A. Drosten C. Zumla A. The Middle East Respiratory Syndrome (MERS).Infect Dis Clin North Am. 2019; 33: 891-905Abstract Full Text Full Text PDF PubMed Scopus (176) Google Scholar). The recent outbreak of clusters of viral pneumonia due to a 2019-nCoV in the Wuhan market poses significant threats to international health and may be related to sale of bush meat derived from wild or captive sources at the seafood market. As of 10 Jan 2020, 41 patients have been diagnosed to have infection by the 2019-nCoV animals. The onset of illness of the 41 cases ranges from 8 December 2019 to 2 January 2020. Symptoms include fever (>90% cases), malaise, dry cough (80%), shortness of breath (20%) and respiratory distress (15%). The vital signs were stable in most of the cases while leucopenia and lymphopenia were common. Among the 41 cases, six patients have been discharged, seven patients are in critical care and one died, while the remaining patients are in stable condition. The fatal case involved a 61 year-old man with an abdominal tumour and cirrhosis who was admitted to a hospital due to respiratory failure and severe pneumonia. The diagnoses included severe pneumonia, acute respiratory distress syndrome, septic shock and multi-organ failure. The 2019-nCoV infection in Wuhan appears clinically milder than SARS or MERS overall in terms of severity, case fatality rate and transmissibility, which increases the risk of cases remaining undetected. There is currently no clear evidence of human to human transmission. At present, 739 close contacts including 419 healthcare workers are being quarantined and monitored for any development of symptoms (WHO, 2020bWHO Emergencies preparedness, response. Pneumonia of unknown origin – China.Disease outbreak news. 2020https://www.who.int/csr/don/12-january-2020-novel-coronavirus-china/en/Google Scholar, Center for Health Protection and HKSAR, 2020Center for Health Protection HKSAR Press Release.2020https://www.info.gov.hk/gia/general/202001/11/P2020011100233.htmGoogle Scholar). No new cases have been detected in Wuhan since 3 January 2020. However the first case outside China was reported on 13th January 2020 in a Chinese tourist in Thailand with no epidemiological linkage to the Huanan Seafood Wholesale Market. The Chinese Health Authorities have carried out very appropriate and prompt response measures including active case finding, and retrospective investigations of the current cluster of patients which have been completed; The Huanan Seafood Wholesale Market has been temporarily closed to carry out investigation, environmental sanitation and disinfection; Public risk communication activities have been carried out to improve public awareness and adoption of self-protection measures. Technical guidance on novel coronavirus has been developed and will continue to be updated as additional information becomes available. However, many questions about the new coronavirus remain. While it appears to be transmitted to humans via animals, the specific animals and other reservoirs need to be identified, the transmission route, the incubation period and characteristics of the susceptible population and survival rates. At present, there is however very limited clinical information of the 2019-nCoV infection and data are missing in regard to the age range, animal source of the virus, incubation period, epidemic curve, viral kinetics, transmission route, pathogenesis, autopsy findings and any treatment response to antivirals among the severe cases. Once there is any clue to the source of animals being responsible for this outbreak, global public health authorities should examine the trading route and source of movement of animals or products taken from the wild or captive conditions from other parts to Wuhan and consider appropriate trading restrictions or other control measures to limit. The rapid identification and containment of a novel coronavirus virus in a short period of time is a re-assuring and a commendable achievement by China’s public health authorities and reflects the increasing global capacity to detect, identify, define and contain new outbreaks. The latest analysis show that the Wuhan CoV cluster with the SARS CoV.10 (Novel coronavirus - China (01): (HU) WHO, phylogenetic tree ProMED, 2020ProMED “Novel coronavirus - China (01): (HU) WHO, phylogenetic tree”. Archive Number: 20200112.6885385. Accessed 13 Jan 2020. https://www.ecohealthalliance.org/2020/01/phylogenetic-analysis-shows-novel-wuhan-coronavirus-clusters-with-sars.Google Scholar). This outbreak brings back memories of the novel coronavirus outbreak in China, the severe acute respiratory syndrome (SARS) in China in 2003, caused by a novel SARS-CoV-coronavirus (World Health Organization, 2019aWorld Health Organization SARS (Severe Acute Respiratory Syndrome).2019https://www.who.int/ith/diseases/sars/en/Google Scholar). SARS-CoV rapidly spread from southern China in 2003 and infected more than 3000 people, killing 774 by 2004, and then disappeared – never to be seen again. However, The Middle East Respiratory Syndrome (MERS) Coronavirus (MERS-CoV) (World Health Organization, 2019bWorld Health Organization MERS situation update.2019http://applications.emro.who.int/docs/EMROPub_2019_MERA_apr_EN_23513.pdf?ua=1Google Scholar), a lethal zoonotic pathogen that was first identified in humans in the Kingdom of Saudi Arabia (KSA) in 2012 continues to emerge and re-emerge through intermittent sporadic cases, community clusters and nosocomial outbreaks. Between 2012 and December 2019, a total of 2465 laboratory-confirmed cases of MERS-CoV infection, including 850 deaths (34.4% mortality) were reported from 27 countries to WHO, the majority of which were reported by KSA (2073 cases, 772 deaths. Whilst several important aspects of MERS-CoV epidemiology, virology, mode of transmission, pathogenesis, diagnosis, clinical features, have been defined, there remain many unanswered questions, including source, transmission and epidemic potential. The Wuhan outbreak is a stark reminder of the continuing threat of zoonotic diseases to global health security. More significant and better targeted investments are required for a more concerted and collaborative global effort, learning from experiences from all geographical regions, through a ‘ONE-HUMAN-ENIVRONMENTAL-ANIMAL-HEALTH’ global consortium to reduce the global threat of zoonotic diseases (Zumla et al., 2016Zumla A. Dar O. Kock R. et al.Taking forward a’ One Health’ approach for turning the tide against the Middle East respiratory syndrome coronavirus and other zoonotic pathogens with epidemic potential.Int J Infect Dis. 2016; 47: 5-9Abstract Full Text Full Text PDF PubMed Scopus (68) Google Scholar). Sharing experience and learning from all geographical regions and across disciplines will be key to sustaining and further developing the progress being made. All authors have a specialist interest in emerging and re-emerging pathogens. FN, RK, OD, GI, TDMc, CD and AZ are members of the Pan-African Network on Emerging and Re-emerging Infections (PANDORA-ID-NET) funded by the European and Developing Countries Clinical Trials Partnership the EU Horizon 2020 Framework Programme for Research and Innovation. AZ is a National Institutes of Health Research senior investigator. All authors declare no conflicts of interest.
BACKGROUND: The impact of extended use of ART in developing countries has been enormous. A thorough understanding of all factors contributing to the success of antiretroviral therapy is required. The current study aims to investigate the value of cross-sectional drug resistance monitoring using DNA and RNA oligonucleotide ligation assays (OLA) in treatment cohorts in low-resource settings. The study was conducted in the first cohort of children gaining access to structured ART in Peru. METHODS: Between 2002-5, 46 eligible children started the standard regimen of AZT, 3TC and NFV Patients had a median age of 5.6 years (range: 0.7-14y), a median viral load of 1.7·105 RNA/ml (range: 2.1·10(3) - 1.2·10(6)), and a median CD4-count of 232 cells/μL (range: 1-1591). Of these, 20 patients were classified as CDC clinical category C and 31/46 as CDC immune category 3. At the time of cross-sectional analysis in 2005, adherence questionnaires were administered. DNA OLAs and RNA OLAs were performed from frozen PBMC and plasma, RNA genotyping from dried blood spots. RESULTS: During the first year of ART, 44% of children experienced virologic failure, with an additional 9% failing by the end of the second year. Virologic failure was significantly associated with the number of resistance mutations detected by DNA-OLA (p < 0.001) during cross-sectional analysis, but also with low immunologic CDC-scores at baseline (p < 0.001). Children who had been exposed to unsupervised short-term antiretrovirals before starting structured ART showed significantly higher numbers of resistance mutations by DNA-OLA (p = 0.01). Detection of M184V (3TC resistance) by RNA-OLA and DNA-OLA demonstrated a sensitivity of 0.93 and 0.86 and specificity of 0.67 and 0.7, respectively, for the identification of virologic failure. The RT mutations N88D and L90M (NFV resistance) detected by DNA-OLA correlated with virologic failure, whereas mutations at RT position 215 (AZT resistance) were not associated with virologic failure. CONCLUSIONS: Advanced immunosuppression at baseline and previous exposures to unsupervised brief cycles of ART significantly impaired treatment outcomes at a time when structured ART was finally introduced in his cohort. Brief maternal exposures to with AZT +/- NVP for the prevention of mother-to-child transmission did not affect treatment outcomes in this group of children. DNA-OLA from frozen PBMC provided a highly specific tool to detect archived drug resistance. RNA consensus genotyping from dried blood spots and RNA-OLA from plasma consistently detected drug resistance mutations, but merely in association with virologic failure.
African swine fever virus (ASFV) is one of the most threatening infectious diseases of pigs. There are not sufficient data to indicate the importance of the sylvatic cycle in the spread and maintenance of the disease locally and potentially, globally. To assess the capacity to maintain ASF in the environment, we investigated the presence of soft tickreservoirs of ASFV in Gorongosa National Park (GNP) and its surrounding villages. A total of 1,658 soft ticks were recovered from warthog burrows and pig pens at the wildlife/livestock interface of the GNP and viral DNA was confirmed by nested PCR in 19% of Ornithodoros porcinus porcinus and 15% of O. p. domesticus. However, isolation of ASFV was only achieved in approximately 50% of the PCR-positive samples with nineteen haemadsorbing virus isolates recovered. These were genotyped using a combination of partial sequencing of the B646L gene (p72) and analysis of the central variable region (CVR) of the B602L gene. Eleven isolates were classified as belonging to genotype II and homologous to contemporary isolates from southern Africa, the Indian Ocean and eastern Europe. Three isolates grouped within genotype V and were similar to previous isolates from Mozambique and Malawi. The remaining five isolates constituted a new, previously unidentified genotype, designated genotype XXIV. This work confirms for the first time that the virus currently circulating in eastern Europe is likely to have a wildlife origin, and that the large diversity of ASFV maintained in wildlife areas can act as a permanent sources of different strains for the domestic pig value chain in Mozambique and beyond its boundaries. Their genetic similarity to ASFV strains currently spreading across Europe justifies the need to continue studying the sylvatic cycle in this African country and other parts of southern Africa in order to identify potential hot spots of ASF emergence and target surveillance and control efforts.
Dolutegravir (DTG) is the latest integrase inhibitor (INI) to be approved for the treatment of HIV-1 infection, with a high antiviral effect, excellent efficacy and safety profile [1,2]. Although DTG seems to show a high genetic barrier, its resistance profile has not yet been established, particularly in patients with failure on an INI-based regimen [3]. The VIKING-3 study among patients with INI-resistant virus reported that the maximum reduction in DTG susceptibility occurred when Q148 was accompanied by at least two other major mutations. For these patients, the odds of achieving HIV-RNA less than 50 copies/ml were 96% lower than those of patients with no evidence of Q148 mutations, even when DTG was dosed twice a day (BID) [4,5]. Moreover, the role of archived integrase mutations is still unknown and generally the clinical significance of drug resistance mutations (DRMs) in proviral DNA remains controversial. Several studies showed that DRMs in proviral DNA may be implicated in therapy failure, whereas others reported that genotypic resistance tests on peripheral blood mononuclear cells (PBMCs) did not provide useful information for assessing the risk of virological failure [6–8]. Here, we describe the case of a successful treatment obtained with a DTG-containing regimen in a 55-year-old MSM, harboring mutations archived in PBMCs conferring high-level resistance to the newer INI in the presence of a multidrug class-resistant HIV-1 because of more than 20 years’ antiretroviral therapy (ART). The man has been living with HIV-1 (subtype B) since 1986, with a history of AIDS-defining events and prior failure to four antiretroviral classes [nucleos(t)ide and nonnucleoside reverse transcriptase inhibitors, protease inhibitors, and fusion inhibitors]. He started a raltegravir (RAL)-containing regimen in June 2013, but did not take it on regular basis and failed to achieve a fully suppressed viral load. One year later, resistance to INIs was detected in plasma (E138A, G140S, Q148H); RAL was stopped and since then his treatment has been modified several times according to drug resistance and intolerance. Because of persistent viremia, in February 2015, genotypic resistance typing (GRT) was performed on plasma and PBMCs, revealing the same mutations in both integrase (IN) gene compartments. On the basis of GRT, a therapeutic regimen containing rilpivirine and abacavir/lamivudine was started. Viral load (VL) decreased slightly thereafter, and in December 2015, another GRT performed on plasma disclosed no major DRM in the IN gene. Despite a previous INI failure, due to few therapeutic options, the patient received DTG (BID), emtricitabine and tenofovir disoproxil fumarate. A rapid virological response was observed, and after 3 months, HIV-RNA declined below 37 copies/ml. Viremia was monitored every 12 weeks thereafter and became undetectable after 9 months, whereas CD4+ T cells rose from 120 to 653 cells/μl. In addition, after 1 year of treatment, a GRT performed on HIV-DNA showed the same INI resistance mutations found in 2014. The patient currently maintains undetectable levels of VL. To the best of our knowledge, this is the first report describing virological success after 1 year of DTG treatment in a patient with archived DTG resistance mutations. Furthermore, this report shows that the concordance between viral compartments may differ profoundly under the selective pressures exerted by antiretroviral drugs. We found that the viral mutants had disappeared from the plasma over time, whereas they persisted in PBMCs after treatment interruption, perhaps due to the different rate of virus turnover in these compartments [9,10]. Although the rapid reappearance of DRMs has been hypothesized on treatment reinitiation in the case of archived mutations [8], after more than 1 year from DTG start, our patient is demonstrating excellent virological and immunological responses despite the archived integrase DRM. These findings may be due either to the fact that the HIV-1 genome is often defective in PBMCs after a long-term ART [11], or the current follow-up is too short. In conclusion, this case confirms that DTG is a potent drug that allows complete viral suppression in a brief time, even in ‘difficult patients’ with preexisting resistance to INIs. It also suggests that archived DRMs either in plasma and/or in DNA should not limit the use of DTG as a salvage-treatment option. Future studies are needed to better elucidate the mechanism of resistance to DTG, and to define guidelines for patients with archived mutations, to minimize the risk of DRM emergence under treatment pressure. Acknowledgements Conflicts of interest There are no conflicts of interest.
BACKGROUND: In 1982, the Annals of Virology published a paper showing how Liberia has a highly endemic potential of Ebola warning health authorities of the risk for potential outbreaks; this journal is only available by subscription. Limiting the accessibility of such knowledge may have reduced information propagation toward public health actors who were indeed surprised by and unprepared for the 2014 epidemic. Open access (OA) publication can allow for increased access to global health research (GHR). Our study aims to assess the use, cost and impact of OA diffusion in the context of GHR. METHOD: A total of 3366 research articles indexed under the Medical Heading Subject Heading "Global Health" published between 2010 and 2014 were retrieved using PubMed to (1) quantify the uptake of various types of OA, (2) estimate the article processing charges (APCs) of OA, and (3) analyse the relationship between different types of OA, their scholarly impact and gross national income per capita of citing countries. RESULTS: Most GHR publications are not available directly on the journal's website (69%). Further, 60.8% of researchers do not self-archive their work even when it is free and in keeping with journal policy. The total amount paid for APCs was estimated at US$1.7 million for 627 papers, with authors paying on average US$2732 per publication; 94% of APCs were paid to journals owned by the ten most prominent publication houses from high-income countries. Researchers from low- and middle-income countries are generally citing less expensive types of OA, while researchers in high-income countries are citing the most expensive OA. CONCLUSIONS: Although OA may help in building global research capacity in GHR, the majority of publications remain subscription only. It is logical and cost-efficient for institutions and researchers to promote OA by self-archiving publications of restricted access, as it not only allows research to be cited by a broader audience, it also augments citation rates. Although OA does not ensure full knowledge transfer from research to practice, limiting public access can negatively impact implementation and outcomes of health policy and reduce public understanding of health issues.
TT virus (TTV) is an unenveloped virus with a single-stranded, circular DNA genome of 3,818-3,853 nucleotides (nt) that infects humans and non-human primates. Recently, the existence of a novel human virus, TTV-like mini virus (TLMV), that shows a genetic organization similar to that of TTV, but with smaller virion particle and genome, was proposed [Takahashi et al. (2000) Archives of Virology 145:979-993]. To date, no information is available with respect to the prevalence and pathogenicity of TLMV. A sensitive PCR assay was developed by using two oligonucleotide primers (LS2 and LA2) designed from the conserved non-coding region of the TLMV genome. One hundred thirty-seven sera from volunteer Brazilian blood donors were tested and 99 (72%) were TLMV DNA positive. No significant differences were observed between the groups of TLMV positive and negative subjects in relation to sex ratio, seroprevalence of TTV DNA, prevalence of anti-hepatitis A virus antibodies, area of residence, occurrence of daily contact with animals, family income, education level, and level of alanine aminotransferase. The specificity of the PCR assay was demonstrated after cloning of amplification products and determination of the nucleotide sequences (200-228 nt) of clones derived from 23 individuals. When DNAs extracted from TLMV/TTV-coinfected sera were submitted to PCR with LS2 and LA2 primers, the amplification products were derived exclusively from the TLMV genome. A markedly wide range of sequence divergence, even higher than that existent among TTV strains, was noted among TLMV isolates, with a maximum evolutionary distance of 0.80.
Pandemic strains of influenza A virus arise by genetic reassortment between avian and human viruses. Pigs have been suggested to generate such reassortants as intermediate hosts. In order for pigs to serve as 'mixing vessels' in genetic reassortment events, they must be susceptible to both human and avian influenza viruses. The ability of avian influenza viruses to replicate in pigs, however, has not been examined comprehensively. In this study, we assessed the growth potential of 42 strains of influenza virus in pigs. Of these, 38 were avian strains, including 27 with non-human-type haemagglutinins (HA; H4 to H13). At least one strain of each HA subtype replicated in the respiratory tract of pigs for 5 to 7 days to a level equivalent to that of swine and human viruses. These results indicate that avian influenza viruses with or without non-human-type HAs can be transmitted to pigs, thus raising the possibility of introduction of their genes into humans. Sera from pigs infected with avian viruses showed high titres of antibodies in ELISA and neutralization tests, but did not inhibit haemagglutination of homologous viruses, cautioning against the use of haemagglutination-inhibition tests to identify pigs infected with avian influenza viruses. Co-infection of pigs with a swine virus and with an avian virus unable to replicate in this animal generated reassortant viruses, whose polymerase and HA genes were entirely of avian origin, that could be passaged in pigs. This finding indicates that even avian viruses that do not replicate in pigs can contribute genes in the generation of reassortants.
DNA restriction analysis was carried out on a sample of 73 adenovirus strains isolated in Buenos Aires from nasopharyngeal aspirates of children with lower acute respiratory infection between 1984 and 1988. Thirty-five isolates (47.9%) were classified as members of subgenus B. Of these, three were identified as a new genome type of Ad3p denominated Ad3p3; five strains corresponded to genome type 7b and two to genome type 7c. The other 25 isolates were identified as the recently recognized genome type 7h. All 6 fatalities recorded within this group of 73 children were associated with infection by Adenovirus genome type 7h. Thirty-seven isolates (50.7%) were classified within subgenus C that corresponded to 9 different genome types denominated 1p (n = 5); 1# (n = 2); 2p (n = 4); 2b (n = 6); 2# (n = 5); 5# (n = 4); 5* (n = 7) and 5+ (n = 2). All genome types of subgenus C were compared with the data reported by Adrian et al. (Archives of Virology 112:235-238, 1990). The Ad1p and Ad1# genome types could be allocated to AV1 genome types D1 and D10, respectively. Ad2b genome type could be allocated to AV2 genome type D25. No counterparts were found for the remaining 6 genomic variants. Only one isolate was identified as Ad4a of subgenus E. The comparison of the results of the present study with those of the molecular characterization of Chilean strains isolated between 1984 and 1987 suggests that the adenovirus strains associated with respiratory disease of children may be common in both countries.
Abstract The present outbreak of lower respiratory tract infections, including respiratory distress syndrome, is the third spillover, in only two decades, of an animal coronavirus to humans resulting in a major epidemic. Here, the Coronavirus Study Group (CSG) of the International Committee on Taxonomy of Viruses, which is responsible for developing the official classification of viruses and taxa naming (taxonomy) of the Coronaviridae family, assessed the novelty of the human pathogen tentatively named 2019-nCoV. Based on phylogeny, taxonomy and established practice, the CSG formally recognizes this virus as a sister to severe acute respiratory syndrome coronaviruses (SARS-CoVs) of the species Severe acute respiratory syndrome-related coronavirus and designates it as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To facilitate communication, the CSG further proposes to use the following naming convention for individual isolates: SARS-CoV-2/Isolate/Host/Date/Location. The spectrum of clinical manifestations associated with SARS-CoV-2 infections in humans remains to be determined. The independent zoonotic transmission of SARS-CoV and SARS-CoV-2 highlights the need for studying the entire (virus) species to complement research focused on individual pathogenic viruses of immediate significance. This research will improve our understanding of virus-host interactions in an ever-changing environment and enhance our preparedness for future outbreaks.
Phlebotomine sandflies transmit pathogens that affect humans and animals worldwide. We review the roles of phlebotomines in the spreading of leishmaniases, sandfly fever, summer meningitis, vesicular stomatitis, Chandipura virus encephalitis and Carrión's disease. Among over 800 species of sandfly recorded, 98 are proven or suspected vectors of human leishmaniases; these include 42 Phlebotomus species in the Old World and 56 Lutzomyia species in the New World (all: Diptera: Psychodidae). Based on incrimination criteria, we provide an updated list of proven or suspected vector species by endemic country where data are available. Increases in sandfly diffusion and density resulting from increases in breeding sites and blood sources, and the interruption of vector control activities contribute to the spreading of leishmaniasis in the settings of human migration, deforestation, urbanization and conflict. In addition, climatic changes can be expected to affect the density and dispersion of sandflies. Phlebovirus infections and diseases are present in large areas of the Old World, especially in the Mediterranean subregion, in which virus diversity has proven to be higher than initially suspected. Vesiculovirus diseases are important to livestock and humans in the southeastern U.S.A. and Latin America, and represent emerging human threats in parts of India. Carrión's disease, formerly restricted to regions of elevated altitude in Peru, Ecuador and Colombia, has shown recent expansion to non-endemic areas of the Amazon basin.
BACKGROUND: Currently, a lack of consensus exists on how best to perform and interpret quantitative real-time PCR (qPCR) experiments. The problem is exacerbated by a lack of sufficient experimental detail in many publications, which impedes a reader's ability to evaluate critically the quality of the results presented or to repeat the experiments. CONTENT: The Minimum Information for Publication of Quantitative Real-Time PCR Experiments (MIQE) guidelines target the reliability of results to help ensure the integrity of the scientific literature, promote consistency between laboratories, and increase experimental transparency. MIQE is a set of guidelines that describe the minimum information necessary for evaluating qPCR experiments. Included is a checklist to accompany the initial submission of a manuscript to the publisher. By providing all relevant experimental conditions and assay characteristics, reviewers can assess the validity of the protocols used. Full disclosure of all reagents, sequences, and analysis methods is necessary to enable other investigators to reproduce results. MIQE details should be published either in abbreviated form or as an online supplement. SUMMARY: Following these guidelines will encourage better experimental practice, allowing more reliable and unequivocal interpretation of qPCR results.
OBJECTIVES: To determine the frequency of symptomatic congenital cytomegalovirus (CMV) infection in the offspring of women with a recurrent maternal CMV infection and to characterize the demographic and newborn findings. METHODS: Study subjects consisted of infants with symptomatic congenital CMV infection identified by a newborn virologic screening program at the University of Alabama Hospital between 1991 and 1997 and were enrolled in a long-term follow-up study. Maternal infections were categorized by an analysis of archival serum specimens collected before pregnancy and at the time of delivery. Demographic data and clinical findings at birth were collected from maternal and newborn hospital records and from parents at the time of initial evaluation. RESULTS: Of the 47 infants with symptomatic congenital CMV infection identified during the study period, 8 were born to mothers with a confirmed nonprimary or recurrent CMV infection. The type of maternal infection could be ascertained in only approximately 43% (20/47) of the children with symptomatic congenital CMV infection born at the University of Alabama Hospital during the study period. There were no significant differences in demographic characteristics of the recurrent infection group and the infants who were born to mothers with either primary CMV infection during pregnancy or unclassified maternal infection. Similarly, the range of severity of clinical abnormalities during the newborn period did not differ in the two groups of children. Furthermore, there were no significant differences in the incidence of sequelae at long-term follow-up in the two groups of children. CONCLUSIONS: Symptomatic congenital CMV infection can occur after a nonprimary or recurrent maternal infection. However, the exact incidence of symptomatic congenital CMV infection among children born to women with preexisting immunity remains to be defined.
BACKGROUND: Human bocavirus (HBoV) and PARV4 are newly discovered human parvoviruses. HBoV, which was first detected in respiratory samples, has a potential role in the development of human respiratory disease. The present study compared the frequencies, epidemiological profiles, and clinical backgrounds of HBoV and PARV4 infections with those of other respiratory virus infections, by evaluating diagnostic samples referred to the Specialist Virology Laboratory (SVL) at the Royal Infirmary of Edinburgh (Edinburgh, United Kingdom). METHODS: Anonymized samples and study subject information were obtained from the respiratory sample archive of the SVL. Samples were screened for HBoV, PARV4, B19, respiratory syncytial virus (RSV), adenoviruses, influenza viruses, and parainfluenza viruses by use of nested polymerase chain reaction. RESULTS: HBoV infection was detected in 47 (8.2%) of 574 study subjects, ranking third in prevalence behind RSV infection (15.7%) and adenovirus infection (10.3%). Peak incidences of HBoV were noted among infants and young children (age, 6-24 months) during the midwinter months (December and January) and were specifically associated with lower respiratory tract infections. HBoV infections were frequently accompanied by other respiratory viruses (frequency, 43%), and they were more prevalent among individuals infected with other respiratory viruses (17%), frequently adenovirus or RSV. All respiratory samples were negative for PARV4. CONCLUSIONS: In the present study, HBoV was a frequently detected, potential respiratory pathogen, with a prevalence and an epidemiological profile comparable to those of RSV. Identification of HBoV infections may be clinically important in the future.
BACKGROUND: To clarify whether next-generation sequencing (NGS) can be useful for resistance assessment in virologically suppressed highly treatment-experienced (HTE) individuals with MDR HIV. METHODS: Ninety-one participants from the PRESTIGIO Registry were included. NGS was performed on HIV-DNA at 1%, 5% and 20% cut-offs; major drug resistance mutations (DRMs) were evaluated and compared with those detected in historical plasma genotypic resistance testing (h-GRT). APOBEC editing was also characterized. RESULTS: Participants had a complex and long treatment history [median 23 (IQR 21-25) years of ART exposure) and had been virologically suppressed since a median of 3 (IQR 2-5) years. Among all major DRMs detected by HIV-DNA NGS and/or h-GRT, 30% were exclusively found through NGS. The highest detection rate of historical major DRMs was reached with NGS set at 1%, but unusual substitutions and extensive APOBEC hypermutations suggest technical issues and poor clinical relevance in the 1%-5% interval. At NGS set at 5%, 67.2% of historical major DRMs were detected. The number of major DRMs detected exclusively by DNA-NGS as minority variants (frequency 5%-20%) was significantly higher in individuals who later experienced virological rebound compared with those who maintained virological control [median 2 (IQR 1-3) versus 1 (0-2), P = 0.030] and positively correlated with viraemia levels at rebound (rho = 0.474, P = 0.030). CONCLUSIONS: In non-viraemic people with an MDR virus, HIV-1 DNA NGS set at 5% is an acceptable technical cut-off that might help to reveal mutations with a potential clinical relevance. Moreover, the number of minority resistance mutations additionally detected by NGS might be associated with loss of virological control.
Despite its effectiveness in controlling plasma viremia, antiretroviral therapy (ART) cannot target proviral DNA, which remains an obstacle to HIV-1 eradication. When treatment is interrupted, the reservoirs can act as a source of viral rebound, highlighting the value of proviral DNA as an additional source of information on an individual's overall resistance burden. In cases where the viral load is too low for successful HIV-1 RNA genotyping, HIV-1 DNA can help identify resistance mutations in treated individuals. The absence of treatment history, the need to adjust ART despite undetectable viremia, or the presence of LLV further support the use of genotypic resistance tests (GRTs) on HIV-1 DNA. Conventionally, GRTs have been achieved through Sanger sequencing, but the advances in NGS are leading to an increase in its use, allowing the detection of minority variants present in less than 20% of the viral population. The clinical significance of these mutations remains under debate, with interpretations varying based on context. Additionally, proviral DNA is subject to APOBEC3-induced hypermutation, which can lead to defective, nonviable viral genomes, a factor that must be considered when performing GRTs on HIV-1 DNA.
The state of Georgia banned the use of QR codes for elections, based in part on the assertions of a man who’s boosted false claims about Israel and 9/11。 Now no one knows how ballots will be counted
Introduction: We assessed the kinetics of the clearance of integrase strand transfer inhibitors resistance mutations (INSTIs-RMs) and associated factors from people living with HIV (PWH) displaying suppressed viral replication after virological failure (VF) on an INSTI regimen. Patients and methods: We included PWH with HIV-RNA viral loads ≤20 copies/mL for at least 5 years in whom INSTIs-RM had been identified at least once in a prior RNA resistance genotyping test. HIV DNAs were sequenced by Sanger sequencing (SS) and ultra-deep sequencing (UDS; detection threshold: 5%) every year over the preceding 5 years. Results: = 0.017). Conclusions: We observed a clear trend towards the clearance of archived INSTIs-RM after a long period of virological control leading to changes in the resistance profile in cellular DNA, raising the possibility of studies assessing the recycling of INSTI classes even in the presence of a history of resistance.
Episodes of low-level viremia (LLV), with plasma human immunodeficiency virus type 1 (HIV-1) RNA levels ranging from 50 to 400 copies (c)/ml, occur commonly during highly active antiretroviral therapy (HAART). LLV has been associated with virologic failure of HAART in some studies, while in others LLV did not appear to affect the clinical outcome. To understand the processes leading to LLV, genetic analyses were used to determine whether plasma virions emanated from archived or from newly evolved viral genomes. Episodes of LLV (plasma HIV-1 RNA, 50 to 379 [median, 77] c/ml) were detected in 21/37 (57%) HIV-1-infected children with median plasma HIV-1 RNA levels of <50 c/ml during 79 patient years of HAART. Viral sequences were derived by direct sequencing of PCR products from 21 plasma specimens diluted to end point. In phylogenetic analysis, LLV viral sequences grouped with virus from early in the course of infection in 8/11 subjects. Six specimens had multiple identical viral sequences, suggesting origin from clonally expanded infected cells. LLV plasma virus evolved over time, indicating viral replication, in 3/11 subjects. Two of these had frequent LLV, including the selection of drug-resistant mutants. In summary, plasma virus from episodes of LLV during effective HAART appeared to originate from two distinct processes, (i) clonal outgrowth from long-lived HIV-1-infected cells, presumably following activation and proliferation of these cells, and (ii) ongoing viral replication that included the selection of new drug-resistant mutants. These observations provide a plausible explanation for the divergent clinical outcomes previously associated with LLV.
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