- News archive 2009
30 December 2009 - Oseltamivir- and Amantadine-resistant seasonal influenza A(H1N1)
Researchers in Hong Kong describe an increase in the number of seasonal influenza A(H1N1) virus detections that are doubly resistant to oseltamivir and amantadine. Of 1,509 isolates tested between April and July 2009, 50 (3.3%) were resistant to both oseltamivir and amantadine but remained susceptible to zanamivir. The resistant viruses were not associated with more severe infection. The full report can be found at: http://www.cdc.gov/eid/content/16/1/155.htm
24 December 2009 - New antiviral drug 'favipiravir' shows promise for treatment of H5N1 infection
A report published in the journal 'Proceedings of the National Academy of Sciences' suggests that the antiviral drug, T-705 (favipiravir) shows promise in treating highly pathogenic H5N1 infection. The drug, which is about to enter phase 3 clinical trial in Japan, exhibited marked efficacy even when dosing was delayed for up to 72hr post-infection. The full paper can be found at: http://www.pnas.org/content/early/2009/12/10/0909603107.full.pdf+html
02 December 2009 - WHO statement on oseltamivir resistance in immunocompromised hospital patients
The WHO has issued a briefing note regarding two clusters of oseltamivir resistant influenza A(H1N1) in the UK and USA. Both clusters occurred in single hospital wards amongst patients who were immunocompromsed. All of the influenza viruses contained the same H275Y mutation conferring resistance to oseltamivir and susceptibility to zanamivir. The full statement can be found at: http://www.who.int/csr/disease/swineflu/notes/briefing_20091202/en/index.html
20 November 2009 - Person-to-person spread of oseltamivir resistant H1N1, Wales, UK
The National Public Health Service for Wales (NPHS) has found person-to-person spread of oseltamivir-resistant influenza A(H1N1) in a hospital in South Wales (UK). Five patients, all of who have serious underlying health conditions and immunosuppression, appear to have acquired the infection in hospital. Two patients have recovered and been discharged from hospital, one remains in critical care and two others continue to be treated on the ward with alternative antiviral treatment. The full statement can be found at: http://www.wales.nhs.uk/sites3/news.cfm?orgid=719&contentid=13713
19 November 2009 - WHO review of oseltamivir-resistant pandemic H1N1 cases
A review of 32 oseltamivir resistant pandemic influenza A(H1N1) cases has shown that they are geographically dispersed, not linked and the viruses are all resistant to oseltamivir but susceptible to the other neuraminidase inhibitor drug, Zanamivir. Two factors, reduced immunity and prophylactic antiviral therapy, may have played a role. The full report can be found at: http://www.who.int/wer/2009/wer8444.pdf
23 October 2009 - WHO pandemic (H1N1)2009 update
The World Health Organisation (WHO) Pandemic (H1N1) 2009 - update 71 published today reports that 39 oseltamivir resistant influenza viruses have been detected and characterised worldwide to date. All of the viruses show the H275Y mutation that confers resistance to oseltamivir, but not to zanamivir. The full WHO briefing can be found at: http://www.who.int/csr/disease/swineflu/laboratory23_10_2009/en/index.html
23 October 2009 - FDA issue peramivir 'emergency use authorisation'
The Food and Drug Administration (FDA) in the USA today issued an emergency use authorisation (EUA) to permit the use of the antiviral drug peramivir in hospitalised H1N1 flu patients. Peramivir is administered intravenously which may make it more feasible for critically ill patients, especially those on ventilators. Further information on peramivir can be found at: http://www.cdc.gov/h1n1flu/eua/peramivir.htm
25 September 2009 - WHO briefing note on antiviral resistance
The World Health Organisation (WHO) today published a briefing note on pandemic H1N1 antiviral resistance. To date, 28 oseltamivir-resistant viruses have been detected. Twelve of these were linked to use of the drug for post-exposure prophylaxis, and 6 were in patients with severe immunosuppression. Four more cases involved other patients being treated with the drug and two patients were not on the drug.
In light of these findings the WHO urges clinicians to be alert to two situations which carry a high risk for the emergence of viruses resistant to oseltamivir: i) in patients with severely compromised or suppressed immune systems who have prolonged H1N1 illness and have received oseltamivir (especially if for a long time) but still have evidence of viral replication; ii) in people who receive preventive oseltamivir after exposure to another infected person but then get sick anyway. The full WHO briefing can be found at: http://www.who.int/csr/disease/swineflu/notes/h1n1_antiviral_use_20090925/en/index.html
14 September 2009 - WHO update on oseltamivir-resistant pandemic influenza
The World Health Organisation (WHO) has published an update on the number of cases of oseltamivir-resistant pandemic influenza A (H1N1) identified to date. As of 30 August, 21 virus isolates have been identified which all carry the H275Y mutation which confers oseltamivir resistance. Of these sporadic isolates, 12 have been associated with post-exposure prophylaxis and four with long term oseltamivir treatment in patients with immunosuppression. To date, more than 10,000 isolates have been tested and found to be sensitive to oseltamivir. The full statement can be found at: http://www.who.int/csr/don/2009_09_11/en/index.html
11 September 2009 - Oseltamivir-resistance in patients with known epidemiological links
A paper published today in MMWR (Morbidity and Mortality Weekly Report) describes the first known instance of oseltamivir-resistant H1N1 infection in patients with known epidmiological links. The virus was found in two girls who shared a cabin at a summer camp and had received prophylactic oseltamivir. Respiratory specimens revealed two mutations, including I223V, which has not been reported previously in pandemic influenza A (H1N1) 2009. The paper can be found at: http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5835a1.htm?s_cid=mm5835a1_x
14 August 2009 - Oseltamivir-resistant H1N1 infection in two immunosuppressed patients
A paper published in MMWR (Morbidity and Mortality Weekly Report) describes detection of oseltamivir resistant influenza A (H1N1) in two severely immunosuppressed patients. Initially both patients were infected with oseltamivir-susceptible viruses; oseltamivir resistance developed later during antiviral treatment. The patients were not epidemiologically linked and were treated at different hospitals. No evidence was found that health care practitioners or other patient contacts developed ILI caused by oseltamivir-resistant pandemic influenza virus. The paper can be found at: http://www.cdc.gov/mmwr/preview/mmwrhtml/mm58d0814a1.htm
11 August 2009 - Trial of long-acting antiviral 'laninamivir' shows promise
The Australian drug company Biota today reported positive phase 3 study results from Asian countries of its new antiviral medication laninamivir, a long-acting neuraminidase inhibitor. In adults, a single inhaled dose of the new drug was as effective as oseltamivir taken twice a day for 5 days. Similar trials in children showed the drug was safe and effective. Preclinical studies suggested that the new antiviral is effective against seasonal H5N1 and pandemic H1N1 viruses. The press release can be found at: http://www.biota.com.au/uploaded/154/1021542_25laniphaseiiiclinicaltri.pdf
05 August 2009 - Zanamivir resistant seasonal influenza A (H1N1) viruses
Researchers in Melbourne Australia have identified isolates of seasonal influenza A(H1N1) that are resistant to the neuraminidase inhibitor zanamivir (Relenza). The resistant viruses were found in vitro, and have not been recovered from clinical specimens from patients. The paper can be found at: http://jvi.asm.org/cgi/reprint/JVI.01200-09v1?view=long&pmid=19641000
27 July 2009 - Oseltamivir resistant viruses reported from Canada, Japan and China
Canada has reported its first case of oseltamivir resistant pandemic influenza A (H1N1). The 60-year old man from Quebec recovered quickly and did not require hospitalisation: http://www.ctv.ca/servlet/ArticleNews/story/CTVNews/20090722/h1n1_090722/20090722?hub=TopStories
In a separate report, Japan has announced two more cases of oseltamivir resistant pandemic H1N1. China also announced during a World Health Organization conference call that they may have one more resistant case. Limited information was reported via CIDRAP on 29 July 2009: http://www.cidrap.umn.edu/
08 July 2009 - Viruses resistant to oseltamivir identified
The WHO has reported three sporadic cases of infection with oseltamivir resistant H1N1v. The viruses were identified in patients with mild disease; all three have recovered. Approximately 1000 viruses have been tested for antiviral resistance, and all except these three remain sensitive to oseltamivir. The full statement can be read at: http://www.who.int/csr/disease/swineflu/newsbriefs/h1n1_antiviral_resistance_20090708/en/index.html
06 July 2009 - Oseltamivir resistant virus reported from Hong Kong
Public health authorities in Hong Kong have announced that oseltamivir resistant virus has been identified in a patient who has not taken the drug. There is currently no evidence that oseltamivir-resistant viruses are spreading widely. The World Health Organization is drafting guidance for countries on the use of antivirals. The full report on the resistant virus can be read at: http://www.promedmail.org/pls/otn/f?p=2400:1001:2340850330097616::NO::F2400_P1001_BACK_PAGE,F2400_P1001_PUB_MAIL_ID:1000,78236
11 June 2009 - WHO raises pandemic alert level to phase 6
The World Health Organisation has raised the pandemic alert level from phase 5 to phase 6 indicating that the criteria for a pandemic have now been met. At this early stage, the pandemic can be characterized globally as being moderate in severity. The full statment is available at: http://www.who.int/csr/disease/swineflu/4th_meeting_ihr/en/index.html
15 May 2009 - Swine influenza A H1N1: global surveillance summary published
The Weekly Epidemiological Record, published today, provides an summary of the global surveillance of swine influenza A H1N1. The publication can be found on the WHO website at: http://www.who.int/wer/2009/wer8420/en/index.html
05 May 2009 - Use of antiviral drugs against swine influenza A H1N1
The WHO has today issued some 'Frequently asked questions' on the use of antiviral drugs against swine influenza A H1N1. The information can be found on the WHO website at: http://www.who.int/csr/disease/swineflu/frequently_asked_questions/swineflu_faq_antivirals/en/index.html
29 April 2009 - WHO raises pandemic alert level from phase 4 to phase 5.
On the basis of evidence of sustained human-to-human transmission of swine influenza A H1N1 in at least 2 countries in 1 region, WHO has today raised the pandemic alert level from phase 4 to phase 5. All countries are advised to be on high alert for unusual outbreaks of influenza-like illness and severe pneumonia and to enhance their surveillance activities for the early detection of suspected cases; to implement appropriate case management strategies and to strengthen infection control measures in health facilities.
Detailed information can be found on the WHO website at: http://www.who.int/csr/disease/swineflu/en/index.html
27 April 2009 - WHO raises pandemic alert level from phase 3 to phase 4.
On the basis of available data of confirmed outbreaks of influenza A H1N1 in Canada, the USA and Mexico the WHO has raised the pandemic alert level from phase 3 to phase 4. Given the widespread circulation of the virus, WHO report that containment of the outbreak is no longer possible and recommended that countries focus on mitigation measures.
Detailed information can be found on the WHO website at: http://www.who.int/csr/disease/swineflu/en/index.html
26 April 2009 - Update on swine influenza A H1N1 in the USA and Mexico
As of 26 April, 20 confirmed human cases of influenza A H1N1 have been reported in the USA (New York, California, Teaxas, Kansas and Ohio). Investigation is ongoing in Mexico to clarify the spread and severity of disease which has been reported in 19 of the country's 32 states.
As a result, on the 25th April, the WHO declared the event a Public Health Emergency of International Concern). The full report can be found at: http://www.who.int/csr/don/2009_04_26/en/index.html
24 April 2009 - The WHO reports cases of human infection with swine influenza A H1N1
The WHO has today reported seven confirmed human cases of influenza A H1N1 in the USA (California and Teaxas). In addition, the Govenment of Mexico has reported three separate events following identification of cases of influenza-like illness beginning on 18 March 2009. Eighteen of the cases in Mexico have been confirmed as swine influenza H1N1.
The full report can be found at: http://www.who.int/csr/don/2009_04_24/en/index.html
04 April 2009 - Oseltamivir resistant influenza virus A(H1N1) Europe, 2007-08
A paper describing the circulation of oseltamivir-resistant influenza A(H1N1) in Europe during the 2007-08 season has been published online in the journal Emerging Infectious Diseases. The paper highlights how the prevalence of oseltamivir-resistant viruses varied considerably between countries that participate in EISS during the season, and provides antiviral susceptibility testing data.
The paper can be found at: http://www.cdc.gov/eid/content/15/4/552.htm
18 March 2009 - Drug resistance found in African H5N1 avian influenza viruses
Scientist have reported the results of analysis of 67 avian influenza A(H5N1) viruses from across Africa. The authors report that some of the viruses, which fall into three distinct lineages, have genetic markers that are characteristic of human rather than avian influenza viruses.
Whilst evaluating antiviral resistance, four avian viruses from Egypt were found to carry a mutation conferring resistance to the adamantane class of drugs, and two viruses from human cases in Egypt had the N294S mutation conferring resistance to oseltamivir and reduced sensitivity to zanamivir. No resistance to the neuraminidase inhibitor class of drugs was found amongst the avian African viruses.The paper can be found at: http://www.plosone.org/article/info:doi/10.1371/journal.pone.0004842
04 March 2009 - Oseltamivir resistant influenza A viruses circulating in Japan
Results of surveillance undertaken in Japan during the 2007-08 influenza season have been published online in the Journal of Clinical Microbiology. The authors report that 202 specimens were analysed from patients infected with influenza A H1N1 and three of these were found to be oseltamivir resistant. Phylogenetic analysis showed that one of the viruses was from the lineage circulating in Europe and North America, and that the other two viruses had emerged independently in Japan.
The abstract and link to the full text paper can be found at: http://jcm.asm.org/cgi/content/abstract/JCM.02396-08v1
02 March 2009 - Studies show that oseltamivir resistant influenza A(H1N1) viruses do not lose fitness
Two studies published online in the Journal of the American Medical Association (JAMA) today show that oseltamivir resistant influenza A(H1N1) viruses are not compromised in their virulence.
In the first study, authors at the Centers for Disease Control (CDC) compared people infected with oseltamivir-resistant and oseltamivir-susceptible strains of H1N1 last season and found no differences in patient characteristics, symptoms, or severity of illness. They report that four patients infected with resistant strains died. The second study describes an outbreak of resistant H1N1 infections in four patients in a Dutch hospital in February 2008. Three immunocompromised patients became ill after exposure to a patient who was sick with a resistant H1N1 strain. Genetic analysis showed that the viruses all matched, indicating that there was person-to-person spread in the hospital.The studies, along with an accompanying editorial, can be found at: http://jama.ama-assn.org/cgi/content/full/2009.294 ; http://jama.ama-assn.org/cgi/content/full/2009.297 and http://jama.ama-assn.org/cgi/content/full/2009.324
05 February 2009 - Use of oseltamivir in 12 European countries: lack of association with the appearance of oseltamivir resistant influenza A(H1N1)
The results of a study looking at the association between oseltamivir use and the emergence of oseltamivir resistant influenza A(H1N1) has been published in 'Eurosurveillance'. Details of the study, which found no association between oseltamivir prescription rates and the proportion of resistant viruses in 12 European countries, can be found at: http://www.eurosurveillance.org/ViewArticle.aspx?ArticleId=19112
02 February 2009 - Oseltamivir-Resistant Influenza Viruses A (H1N1), Norway, 2007/08
A paper reporting the findings of enhanced surveillance for oseltamivir-resistant influenza A (H1N1) viruses in Norway during 2007-08 has been published in the journal 'Emerging Infectious Diseases'. In total, 183 (67.3%) of 272 available H1N1 viruses analysed from the 2007-08 influenza season were found to be osletamivir resistant. Epidemiological and clinical follow-up demonstrated that resistant viruses were not associated with prior antiviral use, and that symptoms and hospitalisation rates did not differ amongst those infected with either a susceptible or resistant virus. The viruses did not show diminshed capability to spread in the absence of selective pressure.
Further information is available at: http://www.cdc.gov/eid/content/15/2/155.htm?s_cid=eid155_e
29 January 2009 - Antiviral resistance of influenza A (H3N2) strains isolated in northern Greece between 2004 and 2007
The results of surveillance for antiviral resistance amongst influenza A (H3N2) viruses in Greece from 2004-2008 has been published in 'Eurosurveillance'. The study examined the sensitivity to the M2 inhibitors (amantidine and rimantidine) and neuraminidase (NA) inhibitors. All strains were susceptible to the adamantanes in 2004-05 compared to 88% of the strains isolated in 2005-6 and 75% of the strains isolated in 2006-7; no known mutations implicated in the resistance to NA inhibitors were found in any of the viruses analysed.
Further information is available at: http://www.eurosurveillance.org/ViewArticle.aspx?ArticleId=19104
29 January 2009 - UK pandemic influenza antiviral stockpile set to double
The UK has awarded contracts to double the emergency stockpile of antiviral drugs. The contracts with GlaxoSmithKline and Roche are expected to be in place by the end of April 2009. The contracts will deliver an additional 7.6 million treatment courses of Tamiflu (Roche) and 10.6 million treatment courses of Relenza (GlaxoSmithKline). Once the extra capacity is in place, there will be 33.5 million treatment courses of antivirals in the UK.
Further details can be found at: http://nds.coi.gov.uk/environment/fullDetail.asp?ReleaseID=391247&NewsAreaID=2&NavigatedFromDepartment=True
22 January 2009 - Start of the influenza season 2008/09 in Europe, and update on antiviral resistance testing
Surveillance data describing the epidemiological and virological characteristics of seasonal influenza at the start of the influenza season 2008-9 in Europe have been published in 'Eurosurveillance'. Antiviral susceptibility data from five countries experiencing early influenza activity are provided.
Further information is available at: http://www.eurosurveillance.org/ViewArticle.aspx?ArticleId=19097
08 January 2009 - United States CDC hosts teleconference on interim recommendations for the use of influenza antiviral medication
Following publication of interim recommendations on the use influenza antiviral medications (24 Dec 2008), CDC today hosted a Clinician Outreach and Communication Activity (COCA) teleconference. Participants were updated on the current status of antiviral resistance in the US, and recieved clinical guidance on the management of oseltamivir-resistant influenza virus infection.
The teleconference audio file, transcript and PowerPoint slides are available at: http://www.emergency.cdc.gov/coca/confcall_archive.asp
