Concern over case of drug resistant swine flu

Jul 2 2009

The influenza A H1N1 (swine flu) outbreak has now spread to almost all corners of the world - the last update, # 56, from the World Health Organisation (WHO) says there are now a grand total of 77,201 confirmed cases including 311 deaths.

That update, issued on the 1st of July, is of course already out of date as more cases are being reported on a daily basis.

According to the WHO the U.S. leads with 27,717 cases including 127 deaths, Mexico has had 8,680 cases including 116 deaths, Canada 7,983 cases including 25 deaths, Chile 6,211 cases including 12 deaths, the UK 6,538 cases including 3 death and Australia 4,090 cases including 7 deaths.

The WHO says the first H1N1 infection found to be resistant to the antiviral drug Tamiflu has occurred but is an isolated case and at present has no implications for public health.

The global pandemic of swine flu has to date been treatable with the drug Tamiflu and the WHO says the discovery of a patient in Denmark whose infection did not respond to the drug, does not mean the severity of the virus has increased.

Danish officials say the patient was found to be infected with a virus strain that had mutated to a form resistant to Tamiflu, but the alternative drug Relenza was effective - flu viruses are known to mutate regularly and can develop resistance to drugs at any time.

The WHO does say however that health authorities must remain alert and not become complacent as the virus can change at any time but that resistance to Tamiflu has been previously documented in the deadly bird flu virus H5N1 and seasonal H1N1 flu.

The WHO says the H1N1 virus must be monitored continuously - the WHO's global influenza surveillance network linking laboratories in 97 countries will see to that but the WHO says current recommendations for the use of antivirals will not be changed at present.

The pandemic flu alert has been raised by the WHO to its highest level of 6, signifying that the first influenza pandemic since 1968 is under way and some experts have expressed concern that Tamiflu might be less effective than Relenza following widespread reports of resistance to Tamiflu by seasonal H1N1 flu, a distant relative of the new swine flu virus.

The U.S. Centers for Disease Control and Prevention (CDC) also says that the isolated case in Denmark did not merit a change in the recommended use of Tamiflu as it remains a relatively mild influenza.

It is estimated that at least 20 companies are currently making flu vaccines some of which are expected to be available in the coming months.