The mutated strain was announced by WHO last week, which said it had been discovered in northern Egypt after tests came back from a 16-year-old girl and her uncle living with their family in the area, and who succumbed to the disease in late December. The mortality rate for the virus in Egypt was about 50 percent in the first half of 2006, but none of the patients treated with Tamiflu in recent weeks have survived. However, in a statement from the organization assured people that there was no evidence of the strain spreading.
"At this time there is no indication that tamiflu resistance is widespread in Egypt or elsewhere," the statement said.
The doctors have gained some hope from treating the two Egyptians. The virus seemed to be slightly weakened by other antiviral drugs, so a cocktail of drugs could end up becoming the primary weapon of health caregivers. According to a spokesperson for the Egyptian health ministry, additional Amantadine antivirals are now being given to bird flu patients to complement Tamiflu.
Eleven people have died from H5N1 since it first appeared in the country a little less than a year ago, making Egypt the hardest-hit country outside of Asia. In response, the Egyptian government has mounted an awareness and education campaign to help lessen the spread of infection to those raising domestic poultry.
Some patients in Vietnam also showed a Tamiflu-resistant strain of bird flu, the New England Journal of Medicine reported in 2005, but the strain did not spread. The H5N1 strain of bird flu is the only strain that has resulted in human fatalities -- 163 worldwide, according to WHO -- but scientists are worried that the strain may eventually mutate into a form easily transmittable between humans.
According to WHO, there are no plans to change the June 2006 recommendations for treating H5N1 patients, because the level of resistance of the mutations have not been determined, and the strain is only moderately resistant. A department of health spokesperson said WHO had noted the level of preparedness and antiviral stockpiling program in Egypt did not require changing, and said the government is attempting to obtain at least 20 million Tamiflu vaccines by the middle of the year. This would enable authorities to treat 15 to 20 percent of the population if H5N1 becomes pandemic, he said.
A professor of microbiology at Hong Kong University was less optimistic, however. Leo Poon Lit-man said that the latest announcement from WHO could mean that the virus is mutating rapidly, which would mean that people should not use Tamiflu too much if they wish to benefit from it. He added that the public should remain vigilant.