Oseltamivir resistance mutations. Medical search. Frequent questions

Initial testing of the 2009 pandemic influenza A (H1N1) virus found it susceptible to neuraminidase inhibitors (oseltamivir and zanamivir) and resistant to adamantanes (amantadine and rimantadine) ( 1 ). (cdc.gov)
The two girls stayed in the same cabin, and both received oseltamivir during a mass chemoprophylaxis program in which approximately 600 campers and staff members received oseltamivir or zanamivir. (cdc.gov)
All but one of the 61 ill campers and four ill staff members received treatment with either oseltamivir or zanamivir. (cdc.gov)
Also, beginning on June 18, medical staff members conducted a mass program of antiviral chemoprophylaxis in which prophylactic oseltamivir or zanamivir was administered to all persons who had an ill sibling at the camp and to all persons who lived in a cabin with an ill person. (cdc.gov)
Over the two sessions, a total of 418 campers and 189 staff members received 10 days of chemoprophylaxis with either oseltamivir (75 mg or appropriate weight-based dosing, once daily) or zanamivir (two 5 mg inhalations, once daily). (cdc.gov)
On July 12, a rapid influenza detection test was positive for influenza A. The family declined treatment with zanamivir because of concern over side effects, and the patient's oseltamivir dose was doubled to 75 mg, twice daily, an appropriate therapeutic treatment dose. (cdc.gov)
All tested isolates were susceptible to 4 neuraminidase inhibitors (oseltamivir, zanamivir, peramivir and laninamivir). (who.int)
Neuraminidase inhibitors (NAIs), such as oseltamivir and zanamivir, are the medicines of choice against influenza A or B. Oseltamivir resistance can be conferred by a single point missense mutation from histidine to tyrosine at position 275 (H275Y) of the neuraminidase gene. (eurekaselect.com)
of further concern, strains demonstrating low level resistance to both oseltamivir and zanamivir have been reported. (eurekaselect.com)
Zanamivir and oseltamivir, which are prodrugs processed in vivo to their active form, can inhibit both IAV and IBV replication, reducing the duration time of virus release. (pharmacytimes.com)
The neuraminidase inhibitors oseltamivir and zanamivir are the primary antiviral agents recommended for the treatment of influenza infections, 4,5 yet antiviral resistance to influenza A viruses is increasingly being reported. (who.int)
Of 3,372 samples tested for susceptibility to the neuraminidase inhibitors oseltamivir and zanamivir, two A(H1N1)pdm09 viruses showed highly reduced inhibition against oseltamivir. (bvsalud.org)
The most widely prescribed NAI is oral oseltamivir, while inhaled zanamivir is less commonly used. (bvsalud.org)
Using phenotypic neuraminidase (NA) enzymatic assays and molecular modeling approaches, we examined the ability of the investigational orally-dosed NAI AV5080 to inhibit viruses of the influenza A(H1N1)pdm09, A(H3N2), A(H5N1), and A(H7N9) subtypes and the influenza B/Victoria- and B/Yamagata-lineages containing NA substitutions conferring oseltamivir or zanamivir resistance including: NA-R292K, NA-E119G/V, NA-H274Y, NA-I122L/N, and NA-R150K. (bvsalud.org)
Broadly, AV5080 showed enhanced in vitro efficacy when compared with oseltamivir and/or zanamivir. (bvsalud.org)
The resistance profiles and predicted binding modes of AV5080 and zanamivir are most similar, but dissimilar to those of oseltamivir, in part because of a guanidine moiety compensatory binding effect. (bvsalud.org)
The result of offering zanamivir and oseltamivir prophylactically led to a relative reduced amount of 70-90% in the chances of developing flu, with regards to the technique adopted and the populace studied. (researchdataservice.com)
Conclusions Proof from randomised managed trials consistently works with the watch that both oseltamivir and zanamivir are medically effective for dealing with and stopping flu. (researchdataservice.com)
Limitations of the medicines include rapid introduction of level of resistance,2,3 insufficient antiviral activity against influenza B, and regular adverse central anxious system events, especially in seniors.4,5 The purpose of offering activity against influenza A and B with few adverse events was included with the introduction of the neuraminidase inhibitors for flu, zanamivir (Relenza, GlaxoSmithKline) and oseltamivir (Tamiflu, Roche). (researchdataservice.com)
With this organized review, commissioned from the Country wide Institute for Clinical Brilliance (Fine), we analyzed randomised controlled studies of zanamivir and oseltamivir, both for treatment and prophylaxis, in three populationschildren, risky adults, and usually healthy adultsto measure the proof for the scientific effectiveness of the two medications. (researchdataservice.com)
The results of the organized review were included into an financial decision model to create the NICE help with 69440-99-9 supplier zanamivir and oseltamivir, that was released in Feb 2003.6 Strategies Searching We researched Medline (1966 to Dec 2001), Embase (1980 to Dec 2001), Integrated Research Citation Index (1981 to Dec 2001), as well as the Country wide Library of Medication (PubMed). (researchdataservice.com)
Selection We chosen randomised controlled, dual blind studies that met all of the pursuing criteria: were released in English, acquired data obtainable before 31 Dec 2001, examined treatment or avoidance of naturally taking place influenza with zanamivir or oseltamivir (if we were holding provided using the formulation and medication dosage licensed for scientific make use of), and reported at least one end stage of relevance (find below). (researchdataservice.com)
Resistance phenotype of these recombinant viruses was determined by NA-inhibition (NAI) assays based on a fluorometric method using two NAIs (oseltamivir and zanamivir). (ophrp.org)
NA-inhibition assays showed that all the single and double mutants containing the Y275 except the single Y275-E119V mutant conferred important levels of resistance to oseltamivir, whereas all the single, double, and triple mutants containing the E119V mutation were associated with the resistance to zanamivir. (ophrp.org)
Influenza viruses are treated with two classes of drugs: M2 blockers (adamantanes) and neuraminidase inhibitors (NAIs), including oseltamivir and zanamivir. (medicaldesignandoutsourcing.com)
These findings suggest that oseltamivir may not be the frontline drug of choice in hematology patients, and zanamivir may prove to be more beneficial," the study authors wrote. (medicaldesignandoutsourcing.com)
Oseltamivir was given for a total of 7 d and zanamivir for 3 d. (blogspot.com)
NAIs were either oseltamivir, zanamivir (Relenza), or peramivir (Rapivab), based on local standard of care. (medpagetoday.com)
The Cochrane Collaboration published an evidence review of Tamiflu (the antiviral drug oseltamivir) and Relenza (zanamivir) trials, reporting that Tamiflu shortens symptoms of influenza but other claims made for the drugs were not well supported by evidence from clinical study reports. (sciencemediacentre.org)
The current therapeutic regimen for influenza A viruses is limited to two classes of drugs: the adamantanes (amantadine and rimantadine) and the neuraminidase inhibitors (oseltamivir and zanamivir). (distantreader.org)
The resistance to zanamivir is rare [17] , but its use is limited to patients who can actively inhale it, which often excludes young children, impaired older adults or patients with underlying airway disease [14] , that is the groups of patients most vulnerable to serious influenza infection complications. (distantreader.org)
Multidrug resistance of the pandemic H1N1-2009 strain of influenza has been reported due to widespread treatment using the neuraminidase ( NA) inhibitors, oseltamivir ( Tamiflu ), and zanamivir ( Relenza ). (pharmaceuticalintelligence.com)
From clinical data , the single I223R (IR (1) ) mutant of H1N1-2009 NA reduced efficacy of oseltamivir and zanamivir by 45 and 10 times, respectively. (pharmaceuticalintelligence.com)
The simulations, run using graphical processors ( GPUs ), were used to investigate the effect of conformational change upon binding of the NA inhibitors oseltamivir and zanamivir in the wild-type and the IR and IRHY mutant strains. (pharmaceuticalintelligence.com)
The antiviral drugs indicated for the treatment and chemoprophylaxis of influenza are the neuraminidase inhibitors (ie, oseltamivir and zanamivir). (medscape.com)

This is the first report of oseltamivir resistance in pandemic H1N1 cases with an epidemiologic link. (cdc.gov)
Enteric absorption and pharmacokinetics of oseltamivir in critically ill patients with pandemic (H1N1) influenza. (cdc.gov)
Two percent (17/811) H1N1 (2009) viruses tested in the U.K. have been found to carry the H275Y mutation which confers resistance to the antiviral drug oseltamivir. (flutrackers.com)
The WHO said it was investigating the extent of resistance worldwide to Tamiflu, known generically as oseltamivir, in some seasonal H1N1 flu viruses that have a mutation making them "highly resistant. (yourlawyer.com)
Â "The frequency of oseltamivir resistance in H1N1 viruses in the current influenza season is unexpected and the reason why a higher percentage of these viruses are resistant is currently unknown," the WHO said. (yourlawyer.com)
the mutated H1N1 is a sub-type of influenza A.Â Of 16 samples from Norway, 12 tested positive for Tamiflu resistance. (yourlawyer.com)
Oseltamivir resistance in seasonal influenza A/H1N1 strains rose markedly during the 2007-2008 season. (eurekaselect.com)
Furthermore, oseltamivir resistant (OsR) strains of pandemic influenza A/H1N1 2009 (influenza A(H1N1)pdm09) have been increasingly isolated, although the majority remain sensitive. (eurekaselect.com)
Jordanian H1N1 viruses had mutations that are characteristic of antigenic group 6 while H3N2 virus mutations belonged to group 3. (who.int)
Peu de renseignements sont disponibles sur les mutations des virus saisonniers de la grippe A(H1N1)pdm09 et H3N2 en Jordanie. (who.int)
Afin de remédier à ce problème et d'étudier les variations génétiques et antigéniques des virus A(H1N1)pdm09 et H3N2, nous avons procédé à des analyses génétiques et phylogénétiques des gènes de l'hémagglutinine (HA) et de la neuraminidase (NA) de ces virus, sur la période 2011-2013 en Jordanie. (who.int)
L'analyse a porté sur les séquences complètes des gènes de l'HA et de la NA de 16 échantillons positifs au virus H1N1 prélevés dans le cadre de cette étude, ainsi que sur 21 séquences publiées de l'HA et 20 séquences publiées de la NA, issues de virus jordaniens disponibles sur les bases de données de gènes en ligne. (who.int)
Les virus H1N1 jordaniens présentaient des mutations caractéristiques du groupe antigénique 6, tandis que les virus H3N2 appartenaient au groupe 3. (who.int)
In 2009, oseltamivir resistance was observed in 100% (19 of 19) of seasonal A(H1N1) isolates and 1.4% (3/215) of A(H1N1)pdm09 isolates. (who.int)
6,7 Oseltamivir is currently recommended as the first-line option by the Viet Nam Ministry of Health for treating suspected infections of A(H5N1) and A(H1N1)pdm09. (who.int)
8,9 In Viet Nam, oseltamivir-resistant strains harboring mutations at positions I117V, H275Y and N295S were reported for A(H5N1) in 2005, 6 A(H1N1) in 2007 10 and A(H1N1)pdm09 in 2009. (who.int)
This chalcone analog, containing a 2,6-dimethoxyphenyl moiety, exhibited significant inhibitory activity against oseltamivir-resistant strains (H1N1 pdm09), with an EC50 value of 1.34 µM. (bvsalud.org)
The results demonstrated that N30 inhibited the replication of H1N1, H3N2, influenza B viruses, including oseltamivir and amantadine resistant strains in vitro. (biomedcentral.com)
The objective of this work was to compare the fitness of two strains of OR (R6 and R7) containing the H275Y mutation, and a wild-type (F) pandemic influenza A (H1N1) 2009 (pdm09) virus both in vitro and in vivo in mice and to select one OR strain for a comparison with F in ferrets. (bris.ac.uk)
However, resistance to both antivirals has been observed in clinical isolates, and there was widespread resistance to oseltamivir (an NA inhibitor) among H1N1 viruses prior to 2009. (inrae.fr)
To examine the effect of neuraminidase (NA) mutations on the NA inhibitor (NAI) resistance phenotype, the recombinant influenza A/Chungbuk/4448/2008(H1N1) virus isolated in South Korea during the 2008-2009 season was generated by reverse genetics. (ophrp.org)
This correlates with the seeming disappearance of the previously circulating H1N1 strain (called "seasonal") that was resistant to oseltamivir. (chestervetclinic.com)
The study analyzed 28 seasonal H1N1 viruses with dual resistance from 2008 to 2010 from five countries, revealing that additional antiviral resistance could rapidly develop in a previously single-resistant strain as a result of mutation, drug response, or gene exchange with another virus. (medicaldesignandoutsourcing.com)
A second study, conducted by Catherine Moore and colleagues in the United Kingdom, examined an outbreak of oseltamivir resistant (OR) pandemic H1N1 infection in a hematology unit in the UK. (medicaldesignandoutsourcing.com)
The 2009 pandemic H1N1 virus was inherently resistant to adamantine, but was susceptible to and treated with oseltamivir. (medicaldesignandoutsourcing.com)
However, by October 2009, emergence of OR H1N1 had been documented in rare patients on oseltamivir therapy. (medicaldesignandoutsourcing.com)
In the hematology unit that Moore and colleagues studied, eight of the 11 pandemic H1N1 virus infections were resistant to oseltamivir, with half of those cases resulting from direct transmission of the resistant virus. (medicaldesignandoutsourcing.com)
Guidelines may need to be changed to include active screening for the [OR] mutation in hematology patients diagnosed with H1N1 and other patients who are immunocompromised when oseltamivir is used. (medicaldesignandoutsourcing.com)
If high risk groups are more actively monitored, early diagnosis will help prevent the spread of H1N1 viruses, and proper screening for infection and resistance will aid in making proper therapeutic decisions. (medicaldesignandoutsourcing.com)
To the Editor: We detail the development of oseltamivir-resistant pandemic (H1N1) 2009 in a chronically immunocompromised patient and the pitfalls encountered when treating such patients with neuraminidase inhibitors. (blogspot.com)
Oseltamivir-Resistant Pandemic (H1N1) 2009 in Pati. (blogspot.com)
Oseltamivir has been widely used for pandemic (H1N1) 2009 virus infection, and by April 30, 2010, a total of 285 resistant cases were reported worldwide, including 45 in the United Kingdom. (cdc.gov)

A new study showed that while the currently preferred method of using common antiviral medications (like Tamiflu ) is still the best treatment option, there is evidence of the virus developing resistance to these drugs in some cases. (medicap.com)
The patients received antiviral treatment in the form of oseltamivir (Tamiflu) or peramivir . (medicap.com)
Adding baloxavir marboxil (Xofluza) to neuraminidase inhibitors (NAIs), like oseltamivir (Tamiflu), was no better for preventing severe outcomes among patients hospitalized for flu compared with NAIs alone, researchers found. (medpagetoday.com)
Oseltamivir is an anti-viral neuraminidase inhibitor (Tamiflu) used to treat influenza infections. (herbs.news)
One form of the protein makes influenza virus resistant to Oseltamivir (Tamiflu®) Don't worry, these proteins aren't from H5N1, but they do come from a related influenza virus that also infects birds. (digitalworldbiology.com)

Strategies to reduce emergence of resistant strains, such as higher dose oseltamivir regimens, need further examination. (eurekaselect.com)
While monitoring influenza virus resistance as it develops, researchers are prioritizing further investigations to decrease the risk of resistant strains. (pharmacytimes.com)
In the present study, we developed the broad-spectrum antiviral activity of N30 in vitro, including oseltamivir-resistant strains and amantadine-resistant strains of influenza virus, coxsackie B virus, coronavirus, and respiratory syncytial virus. (biomedcentral.com)
Of course, occasional resistance can arise and patients who fail to improve after a week of therapy should be evaluated for drug resistant strains, as well as for other complications. (chestervetclinic.com)
While the spread of influenza strains with resistance to one class of drugs has been well documented in recent years, a new report from Larisa Gubareva, MD, PhD and colleagues at the Centers for Disease Control and Prevention (CDC) and at health agencies in West Virginia, Texas, and Canada, confirms that dual resistance can emerge in several ways and has been on the rise during the past three years. (medicaldesignandoutsourcing.com)
Due to its high mutation rate, the influenza virus has rapidly and continuously evolved and has now generated new strains that are resistant to anti-viral medications commonly used today. (herbs.news)
Some studies have also reported that certain herbal extracts can inhibit the replication of oseltamivir-resistant strains. (herbs.news)
Because all influenza viruses are capable of rapid genetic change, avian strains could possibly acquire the ability to spread more easily from person-to-person via direct mutation or via reassortment of genome subunits with human strains during replication in a human, animal or, avian host. (msdmanuals.com)

On August 14 and August 19, CDC detected the H275Y mutation (N1 numbering) in neuraminidase from both specimens by pyrosequencing ( 3,4 ). (cdc.gov)
This H275Y mutation was not found in influenza subtypes A(H5N1) or A(H3N2) isolates. (who.int)
Neuraminidase activity was measured using a phenotypic method for viral isolates of influenza A and B. Pyrosequencing assays were then applied to detect the common mutations related to reducing susceptibility or resistance of influenza A viruses to oseltamivir - I117V, E119V and H275Y. (who.int)
The acquisition of oseltamivir resistance (OR) mutations, such as H275Y, hampers viral fitness. (bris.ac.uk)
The sample from August 7 did not contain this mutation, suggesting a de novo H275Y substitution secondary to oseltamivir use. (blogspot.com)

Many viruses, especially RNA viruses, rapidly accumulate genetic variation because of short generation times and high mutation rates. (wikipedia.org)
View of Oseltamivir resistance among influenza viruses in northern Viet Nam, 2009-2012. (who.int)
Antiviral resistance has been reported in seasonal influenza A viruses and avian influenza A(H5N1) viruses in Viet Nam, raising concerns about the efficacy of treatment. (who.int)
The presence of oseltamivir-resistant viruses is therefore a concern. (who.int)
Active surveillance for oseltamivir resistance among influenza viruses circulating in Viet Nam should be continued. (who.int)
However, it is a last-resort medication to treat the novel or re-emerging influenza viruses that are resistant to certain antivirals, like oseltamivir [ 1 ]. (springer.com)
These mutations following favipiravir treatment have been observed in other viruses as well [ 1 ]. (springer.com)
Two new studies raise public health concerns about increasing antiviral resistance among certain influenza viruses, their ability to spread, and a lack of alternative antiviral treatment options. (medicaldesignandoutsourcing.com)
Because only two classes of antiviral agents are approved, the detection of viruses with resistance to drugs in both classes is concerning," said Dr. Gubareva. (medicaldesignandoutsourcing.com)
If circulation of viruses with dual resistance becomes more widespread among any of the predominant circulating influenza A viruses, treatment options will be extremely limited. (medicaldesignandoutsourcing.com)
However, the authors also stressed, "The emergence of antiviral resistance in A/H7N9 viruses, especially in patients receiving corticosteroid therapy, is concerning, needs to be closely monitored, and considered in pandemic preparedness planning. (medicap.com)
The danger of using live vaccines, which are usually more effective than killed vaccines, is the low but significant danger that these viruses will revert to their disease-causing form by back mutations . (lumenlearning.com)
Some vaccines are in continuous development because certain viruses, such as influenza and HIV, have a high mutation rate compared to other viruses and normal host cells. (lumenlearning.com)
Errors can easily occur with polymerase enzymes and RNA viruses, resulting in a high rate of mutation. (mometrix.com)
It is likely that avian influenza viruses of any antigenic specificity can cause influenza in humans whenever the virus acquires mutations, enabling it to attach to human-specific receptor sites in the respiratory tract. (msdmanuals.com)

Considering the effect of mutations in NA gene on the resistance to NAIs, it is important to monitor the possible emergence and dissemination of multidrug-resistant variants in the human population due to amino acid changes at NA gene as well as to develop novel NAIs. (ophrp.org)

In this study, we identified an antiviral compound, M85, that targets host kinases, epidermal growth factor receptor (EGFR), and phosphoinositide 3 class II β (PIK3C2β) and is not susceptible to resistance by viral mutations. (inrae.fr)
In the mouse model for influenza, treatment with the combination therapy was more protective against a lethal viral challenge than oseltamivir alone, indicating that development of M85 could lead to combination therapies for influenza. (inrae.fr)
Effective treatment depends partially on immune system destruction of the foci of infection (6), or potential persistent viral particles can be released as soon as oseltamivir therapy is stopped. (blogspot.com)
The authors wrote that since oseltamivir treatment was associated with a reduced viral load in most of the patients, they strongly recommended early treatment with these antiviral drugs in suspected or confirmed cases. (medicap.com)
Because [hospitalized] patients might have higher baseline viral loads and more prolonged viral replication, these patients could benefit from repeat dosing of baloxavir or combination therapy with baloxavir and oseltamivir," the researchers wrote. (medpagetoday.com)
The editorialists also addressed the issue of resistance, noting that giving multiple doses of baloxavir was "logical given the severity of infection and potentially higher viral loads predisposing to resistance after a single dose. (medpagetoday.com)
This increased resistance has compelled the scientific community to explore other compounds that have anti-viral effects against the influenza virus. (herbs.news)
Herbal extracts that contain compounds called pentacyclic triterpenes have exhibited higher anti-viral activity than oseltamivir. (herbs.news)

After completing the initial course of oseltamivir on July 5, she was exposed to an ill cabin mate (patient C) and administered a second 10-day course of chemoprophylaxis at the same dosage beginning on July 7. (cdc.gov)

From 2000 to 2004, amantadine resistance among the A/H3N2 subtype increased from 1.1% to 27% in Asia, and to 4.7%, 3.9%, and 4.3% in Europe, North America, and South America, respectively. (pharmacytimes.com)
We identified an influenza A(H3N2) genome encoding the oseltamivir resistance S331R mutation in neuraminidase, potentially associated with an emerging distinct intra-subtype reassortant. (ox.ac.uk)

Early administration of oral oseltamivir increases the benefits of influenza treatment. (cdc.gov)

Influenza A virus (IAV) is extremely prone to cause periodic epidemics and pandemics in the world through evolution by point mutations or swapping of gene segments, correspondingly [ 1 - 3 ]. (biomedcentral.com)
All three resistant mutants carried mutations in their polymerase gene. (springer.com)

Widespread utilization of directly antiviral drugs accelerates resistance problem, hence host cellular factors become attractive therapeutic targets to treat influenza virus infections. (biomedcentral.com)
Adamantanes (amantadine and rimantadine) were used in the past, but resistance against these agents has become widespread, and they are no longer recommended. (medscape.com)

The progress is sometimes fragile, threatened by factors ranging from drug resistance to uncertain funding for the future. (who.int)
Additionally, NA inhibitors and M2 ion-channel inhibitors have limited efficacies as drug resistance occurrence [ 7 , 8 ], and they only worked at the early phase of virus infection. (biomedcentral.com)
We investigated drug resistance, genetic diversity, and nosocomial transmission using influenza sequence data. (ox.ac.uk)
Conclusion Nanopore metagenomic sequencing can detect the emergence of novel variants and drug resistance, providing timely insights into antimicrobial stewardship and vaccine design. (ox.ac.uk)
This suggests that drug resistance could be overcome by increasing hydrogen bond interactions between NA inhibitors and residues in the 150-loop, with the aim of maintaining the closed conformation, or by designing inhibitors that can form a hydrogen bond to the mutant R223 residue, thereby preventing competition between R223 and R152. (pharmaceuticalintelligence.com)

7,11 The limitations of other antiviral drugs, as well as the risk of oseltamivir resistance, have raised concerns about the efficacy of oseltamivir for influenza infection treatment. (who.int)
This has led to the question of why the efficacy of the NA inhibitors is reduced by the occurrence of these mutations and, specifically, why the efficacy of oseltamivir against the double mutant IRHY was significantly reduced, to the point where oseltamivir has become an ineffective treatment. (pharmaceuticalintelligence.com)
The results suggest that the efficacy of oseltamivir is reduced significantly because of conformational changes that lead to the open form of the 150-loop. (pharmaceuticalintelligence.com)
The efficacy of oseltamivir against avian influenza is not well established. (medscape.com)

Actualización sobre el virus la influenza aviar A (H5N1) en los seres humanos. (cdc.gov)
As an initial step in establishing a surveillance programme for antiviral resistance in northern Viet Nam, genetic analysis was conducted for both clinical specimens and isolates collected through sentinel sites and isolates of influenza A(H5N1). (who.int)

In vitro, we found that combinations of M85 and oseltamivir have strong synergism. (inrae.fr)

Concerning the emergence of resistance to current anti-influenza drugs, our previous phenotypic-based screening study identified the compound A9 as a promising lead compound. (bvsalud.org)
In the case of antiviral drugs, one of the most significant questions is the emergence of resistance. (springer.com)
The emergence of resistance to antiviral drugs in recent years further limits the options available for the control of influenza. (distantreader.org)

Nick's post on Amantadine resistance in swine flu was so interesting, I had to look at the protein structures myself. (digitalworldbiology.com)
I couldn't find any structures with the S31N mutation that Nick discussed, but I did find some structures with the M2 protein and Amantadine. (digitalworldbiology.com)

A second-line alternative is to use a combination of oseltamivir and rimantadine rather than oseltamivir alone. (medscape.com)

The emergence of oseltamivir resistance of clinical isolates of influenza A virus has been associated with substitution at residue V116, I117, E119, Q136, K150, D151, D199, I223, H275 and N295 in the neuraminidase active site.8 For influenza B there have been two main substitutions: residues R152 and D198. (who.int)

Studies have shown that the NA R292K muta- of the mixture a ratio of 50:50 was used as the assay-specif- tion can cause a high level of resistance to oseltamivir in ic normalization value in determination of the percentage influenza A(H7N9) virus ( 4,5 ). (cdc.gov)
A Nature Communications paper showed a mutation in newly emerged H7N9 influenza can render it resistant to the only class of drugs active against the virus, without affecting its ability to spread in animals. (sciencemediacentre.org)

The low genetic barrier to oseltamivir means that resistance is a likely consequence of monotherapy in immunocompromised patients. (blogspot.com)

Patient A. One of the campers, a previously healthy adolescent girl, received oseltamivir prophylaxis at an appropriate prophylactic dose of 75 mg daily during June 26--July 5, despite having no reported exposure to an ill person. (cdc.gov)
Despite these symptoms, her oseltamivir dose was not increased to a therapeutic treatment dose. (cdc.gov)
Initial tests showed a neutrophil count of 2.02 × 109/L, a lymphocyte count of 0.87 × 109/L, and a C-reactive protein level of 33 mg/L. He was started on piperacillin-tazobactam and gentamicin, and oseltamivir was increased to the treatment dose of 75 mg 2×/d. (blogspot.com)

The camp physician observed that the camper became ill while taking prophylaxis and became concerned that antiviral resistance might have occurred. (cdc.gov)

On July 14, CDC was contacted by a physician at a summer camp in North Carolina regarding two cases of influenza-like illness (ILI) in adolescent girls receiving oseltamivir chemoprophylaxis during an ILI outbreak that had begun June 18. (cdc.gov)
Health-care providers should be aware that antiviral resistance can develop during chemoprophylaxis or treatment with subtherapeutic dosages and should follow published recommendations for antiviral medications ( 5 ). (cdc.gov)

Oseltamivir inhibits neuraminidase, an enzyme that breaks the bond between newly produced virions and the host cell membrane. (medscape.com)

6 ). The assay detected the 292K mutant in the mixture rus with this mutation to monitor its circulation and trans- at a proportion of 2% of the 104 copies/reaction, and cor- mission and guide antiviral treatment. (cdc.gov)
A minority of these mutations were detected in treatment-naive patients. (blogspot.com)
Oseltamivir is effective for the treatment of influenza A or B. It must be administered within 48 hours of symptom onset. (medscape.com)

This potential for resistance and lack of diversity for antiviral targets highlights the need for new influenza antivirals with a higher barrier to resistance. (inrae.fr)

While adding baloxavir did not result in improved clinical outcomes, Sridhar and Wang To noted that combination antiviral therapy may lead to "a reduction in antiviral resistance. (medpagetoday.com)

Mutation in plasmids that contained R292 wild-type virus or 292K mu- tant virus, respectively. (cdc.gov)
Oseltamivir is a common therapy against influenza A virus (IAV) infections. (bris.ac.uk)
The authors also found a virus mutation in two patients that is associated with resistance to antiviral drugs. (medicap.com)
Preventive vaccination has historically been the most efficient measure of influenza control, but this approach presents important limitations due to the accumulation of antigenic mutations in the virus, known as antigenic drift. (distantreader.org)
Adaptations to these new cells or temperatures induce mutations in the genomes of the virus, allowing it to grow better in the laboratory while inhibiting its ability to cause disease when reintroduced into conditions found in the host. (lumenlearning.com)
With influenza, mutations in the surface molecules of the virus help the organism evade the protective immunity that may have been obtained in a previous influenza season, making it necessary for individuals to get vaccinated every year. (lumenlearning.com)

Emergence of E484K Mutation Following Bamlanivimab Monotherapy among High-Risk Patients Infected with the Alpha Variant of SARS-CoV-2. (iame-research.center)

Antibiotic resistance: How do antibiotics kill bacteria? (digitalworldbiology.com)
This is a multi-part series on antibiotic resistance in bacteria. (digitalworldbiology.com)
Eventually, we'll reach the ways in which bacteria develop antibiotic resistance, but before we get there, we'll spend a little more time on antibiotics themselves. (digitalworldbiology.com)

We report here on a pilot study for the establishment of a routine antiviral resistance surveillance programme in northern Viet Nam. (who.int)

Organisms3

Diseases2

Chemicals and Drugs13

Analytical, Diagnostic and Therapeutic Techniques and Equipment3

Phenomena and Processes11

Information Science1

Health Care1

Zanamivir35

H1N132

Tamiflu5

Strains8

H275Y5

Viruses15

NAIs1

Viral8

Course of oseltamivir1

H3N22

Oral oseltamivir1

Gene2

Widespread2

Drug resistance5

Efficacy4

H5N12

Vitro1

Emergence of resistance3

Amantadine2

Rimantadine1

Isolates1

H7N92

Genetic1

Dose3

Prophylaxis1

Chemoprophylaxis2

Inhibits1

Treatment3

Antivirals1

Clinical1

Virus6

Monotherapy1

Antibiotic resistance3

Surveillance1