Drug Resistance
Influenza viruses can show resistance to anti-viral drugs. Like the development of bacterial antibiotic resistance, this can result from over-use of these drugs. For example, a recent study published in the June Issue of Nature Biotechnology emphasized the urgent need for augmentation of oseltamivir (Tamiflu) stockpiles with additional antiviral drugs including zanamivir (Relenza) based on an evaluation of the performance of these drugs in the scenario that the 2009 H1N1 'Swine Flu' neuraminidase (NA) were to acquire the tamiflu-resistance (His274Tyr) mutation which is currently widespread in seasonal H1N1 strains. Yet another example is in the case of the amantadines treatment may lead to the rapid production of resistant viruses, and over-use of these drugs has probably contributed to the spread of resistance. In particular, this high-level of resistance may be due to the easy availability of amantadines as part of over-the-counter cold remedies in countries such as China and Russia, and their use to prevent outbreaks of influenza in farmed poultry.
On the other hand, a few strains resistant to neuraminidase inhibitors have emerged and circulated in the absence of much use of the drugs involved, and the frequency with which drug resistant strains appears shows little correlation with the level of use of these drugs. However, laboratory studies have shown that it is possible for the use of sub-optimal doses of these drugs as a prophylactic measure might contribute to the development of drug resistance.
During the United States 2005–2006 influenza season, increasing incidence of drug resistance by strain H3N2 to amantadine and rimantadine led the CDC to recommend oseltamivir as a prophylactic drug, and the use of either oseltamivir or zanamivir as treatment.
Read more about this topic: Influenza Treatment
Famous quotes containing the words drug and/or resistance:
“Behind the steering wheel
The boy took out his own forehead.
His girlfriend’s head was a green bag
Of narcissus stems. “OK you win
But meet me anyway at Cohen’s Drug Store
In 22 minutes.””
—John Ashbery (b. 1927)
“Even the most subjected person has moments of rage and resentment so intense that they respond, they act against. There is an inner uprising that leads to rebellion, however short- lived. It may be only momentary but it takes place. That space within oneself where resistance is possible remains.”
—bell hooks (b. c. 1955)