New militarized flu spreading like wildfire in Mexico City

Flamed Diving wrote: »

Fair enough, but I was really referring to that post. The fact that he was somehow (?) right about a case in Ireland is besides the point. It's his nonsensical, sensationalist posting that baffles me.

Subsequently, the Expert Group reviewed recommendations with regard to stockpiling of zanamivir (Relenza) in addition to oseltamivir. This was in light of a case report of suspected resistance to oseltamivir (Tamiflu), detailed earlier in this chapter. The Expert Group advised that it would be prudent to stockpile a second antiviral agent that would allow for treatment of 20% of the population. The Minister for Health and Children accepted this advice.

The most common side effects of Tamiflu are nausea, vomiting, diarrhoea, stomach ache and headache.
These side effects mostly occur only after the first dose of the medicine and will usually stop as treatment continues. The frequency of these effects is reduced if the medicinal product is taken with food.

Less common side effects of Tamiflu

Adults and adolescents (children aged 13 years and older)
Other less common side effects, which may also be caused by influenza, are upper abdominal fullness, bleeding in the gastrointestinal tract, bronchitis, upper respiratory tract infections, dizziness, tiredness, sleeping difficulties, skin reactions, mild to severe liver function disorders, visual disturbances and heart rhythm abnormalities.
Influenza can be associated with a variety of neurologic and behavioural symptoms which can include events such as hallucinations, delirium, and abnormal behaviour, in some cases resulting in fatal outcomes. These events may occur in the setting of encephalitis or encephalopathy but can occur without obvious severe disease.
During Tamiflu treatment, events like convulsions and delirium (including symptoms such as altered level of consciousness, confusion, abnormal behaviour, delusions, hallucinations, agitation, anxiety, nightmares) have been reported, in a very few cases resulting in accidental injury, in some instances with fatal outcome. These events were reported primarily among children and adolescents and often had an abrupt onset and rapid resolution. The contribution of Tamiflu to those events is unknown.

Such neuropsychiatric events have also been reported in patients with influenza who were not taking Tamiflu.

Children (aged 1 to 12 years)
Other less common side effects, which may also be caused by influenza, are ear inflammation, inflammation of the lungs, sinusitis, bronchitis, aggravation of pre-existing asthma, nose bleeding, ear disorders, inflammation of the skin, swelling of the lymph nodes, conjunctivitis, visual disturbances and heart rhythm abnormalities.

In late January 2008 antiviral drug susceptibility surveillance of seasonal influenza viruses in Europe (the EU-EEA-EFTA countries) revealed that some of the A (H1N1) viruses circulating this season (winter 2007-8) were resistant to the antiviral drug oseltamivir [Tamiflu] through mutation at position 274 in the viral neuraminidase gene.(16)

Analysis of 2499 A/H1N1 viruses from 24 European (European Union, EEA/EFTA) countries isolated between November 2007 and early April (data archived on April 23rd) showed that 577 were resistant to oseltamivir, but retained sensitivity to zanamivir and amantadine. The proportion of A(H1N1) viruses that are oseltamivir resistant varied significantly across Europe. The highest proportion of resistant viruses to date have been in Norway where 168 (67%) of the 252 samples are resistant to oseltamivir, whereas no resistant viruses have been detected in five of the 24 countries. In Ireland, 9.1% are resistant. There is also evidence of similarly resistant viruses in North America and the Far East.

In 2005, Mai Le et al reported isolation of drug resistant H5N1 virus from a Vietnamese girl.(17)

This 15-year-old girl was treated with a prophylactic dose for three days, and then subsequently was given a therapeutic dose for seven days. She recovered. She had not had any direct contact with poultry, but had cared for her brother who had documented H5N1 infection. Although the virus was resistant to oseltamivir, it was sensitive to zanamivir. Since that report, there have been two additional cases reported where H5N1 virus, which is resistant to oseltamivir, was isolated.(18)

In these patients, the viruses were isolated during or shortly after a course of oseltamivir at therapeutic doses.
Both of these patients died. The authors stated that at least in some patients with A(H5N1) infection, treatment with recommended doses of oseltamivir incompletely suppresses viral replication, and that this can allow the infection to proceed, but also provides opportunities for drug resistance to develop.

Ferguson et al have modelled the potential spread of drug resistant influenza infections during community-based use of antivirals.(19)
Looking at different scenarios of usage of oseltamivir, ranging from treatment of 6% of symptomatic infections, to treatment of 40% of symptomatic infections and PEP following 5% of exposure events, they found that the currently isolated strains of influenza exhibiting resistance are unlikely to be transmitted in a frequency that would significantly interfere with the efficacy of even high levels of drug usage. However, this work pre-dated the emergence of resistance of A(H5N1) to oseltamivir in the 2007/2008 season.

The potential human-to-human transmissibility of these variants is a major public health concern. If the A(H1N1) resistance to oseltamivir seen in the 2007/2008 season persists, it could affect our ability to use antiviral drugs during a pandemic, if this resistance were present also in the pandemic strain.

M2 inhibitors (amantadines) in treatment

In 2004, a Cochrane review of the effectiveness and safety of amantadine and rimantadine in healthy adults was carried out. All controlled trials registered up to September 2003 were included. Amantadine prevented 25% of influenza like illness (ILI) cases (95% confidence interval (CI) 13% to 36%), and 61% of influenza A cases (95% CI 35% to 76%). Amantadine reduced duration of fever by one day (95% CI 0.7 to 1.3). Rimantadine demonstrated comparable effectiveness, but there were fewer trials and the results for prevention were not statistically significant. Both amantadine and rimantadine induced significant gastrointestinal adverse effects. Adverse effects of the central nervous system and study withdrawals were significantly more common with amantadine than rimantadine. They concluded that amantadine and rimantadine have comparable effectiveness in the prevention and treatment of influenza A in healthy adults, although rimantadine causes fewer adverse effects than amantadine.

Several placebo controlled prospective studies, during the 1968 H3N2 pandemic and 1977 H1N1 pandemic reappearance, showed that amantadine and rimantadine provided therapeutic benefit in uncomplicated illness in previously healthy adults with reductions in fever, symptom severity and time to resuming normal activities.(20; 21)

No prospective trials to date have documented reductions in complications, antibiotic use or hospitalisations.(22)


Oseltamivir

---

side effects

There have been reports mostly from Japan of neuropsychiatric events including delirium, convulsions, and encephalitis mainly in children and adolescents who were taking oseltamivir. Japan has the highest usage of oseltamivir worldwide.
(25)

In March 2007, Tokyo’s Ministry of Health and Welfare instructed the Japanese distributor of oseltamivir to include a warning not to give the drug to patients aged between 10 and 19, after reports that at least 18 Japanese children taking Tamiflu have died as a result of irrational behaviour. The US Food and Drug Administration (FDA) and the European Medicines Agency (EMEA) reviewed these reports. The relative contribution of the drug to these events is unknown. EMEA has required that doctors be warned that patients should be closely monitored for signs of abnormal behaviour and the summary of product characteristics (available at www.medicines.ie) now states “convulsions, depressed level of consciousness, abnormal behavior, hallucinations and delirium have been reported during Tamiflu administration, leading in rare cases to accidental injury. Patients, especially children and adolescents, should be closely monitored and their healthcare professional should be contacted immediately if the patient shows any signs of unusual behavior”.

tallaght01 wrote: »

Sure.

So, the only proper scientific paper testing masks and their usefullness in a REAL influenza outbreak is:

MacIntyre CR, Epid MA, Cauchemez S, Dwyer DE, Seale H, Cheung P, et al. Face mask use and control of respiratory virus transmission in households. Emerging Infectious Diseases 2009.

There's very litle other actual evidence out there.

There's also no good scientific evidence that this virus is too small for the N95 mask.

You'll see that a big finding in this study is that compliance is a big issue in the success of masks. That's one of the reasons N95 masks are probably better. They are easier to breath through. But there's no good evidence at all for N99 masks.

That's why the WHO recommends the N95:

http://www.who.int/csr/resources/publications/20090429_infection_control_en.pdf

No one is trying to kill you!!! I, and the guys in the WHO and CDC, work silly hours when diseases spread! It's saturday night on a bank holiday weekend. I was in work at 8am today because of this thing. I'll be back in tomorrow morning,

Also, there are no cases of human swine flu in Ireland yet.

In our study, fit testing for P2 masks was not conducted because this is unlikely to be feasible in the general community during a pandemic. As such, we felt it was more appropriate to determine the efficacy of non–fit-tested masks. We found no difference in adherence between P2 and surgical masks, an important finding, as there is a common belief among healthcare workers that P2 masks are less comfortable. The size of the study did not permit conclusive comparison of the relative efficacy of P2 masks and surgical masks. Given the 5- to 10-fold cost difference between the 2 mask types, quantifying any difference in efficacy between surgical masks and particulate respirators remains a priority that needs to be addressed by a larger trial.

Conversely, the low rate of confirmed influenza A or B infection (18.4%) in the study could mean that our findings are not directly applicable to a scenario in which influenza predominates. If influenza is more likely than the other viruses in our study to be transmitted by the respiratory route, the prevalence of mixed infections would tend to bias our results toward the null. However, it is possible that a pandemic strain may have different transmission characteristics than seasonal strains as demonstrated by attack rates in different age groups in pandemics compared with seasonal outbreaks and by the detection of influenza virus in different clinical samples in human influenza virus A (H5N1) cases.