Mar 10, 2011
Egypt reports more H5N1 cases, two fatal
Egypt's health ministry has announced two new H5N1 avian influenza cases, one of them fatal, and that a woman whose infection was previously reported has died, the World Health Organization (WHO) said today. The newest case-patients are both 17-year-old girls, one from Beheira governorate and one from Dakahlia governorate. Both were treated with oseltamivir (Tamiflu). The girl from Beheira got sick on Feb 27 and was hospitalized on Mar 1, where she is in stable condition. The girl from Dakahlia started having flu-like symptoms on Feb 24 and was hospitalized 2 days later. She died on Feb 28. The second death is a 32-year-old woman from Sharkia governorate whose illness was reported by the WHO on Mar 7. She had been hospitalized since Feb 14 and was in critical condition. Investigations into all three cases revealed exposure to sick and dead poultry. The two new cases and deaths raise Egypt's H5N1 total to 129 cases, including 43 deaths. They also push the world's H5N1 count to 530 cases, 313 of them fatal.
Mar 10 WHO statement
Researchers identify possible H5N1 China-Tibet migration route
Using GPS tracking, a team of US, Chinese, and UN researchers identified a new migratory pathway that may serve as a transmission route for H5N1 avian flu between China and Tibet, and genetic analysis seems to confirm the hypothesis. The researchers fitted 29 bar-headed geese with GPS satellite transmitters at Qinghai Lake, China's largest lake, which sits along several major migratory flyways. In 2005, H5N1 killed 6,000 birds at the lake, including 3,000 bar-headed geese. In tracking the marked geese's movements, the team discovered a previously unidentified migratory pathway from Qinghai Lake to the Lhasa Valley of Tibet, where all but one of the geese wintered. From 2003 through 2009, 16 H5N1 outbreaks in poultry or wild birds were confirmed on the Qinghai-Tibet Plateau, and most were within this newly identified pathway. The scientists wrote, "Ample opportunities existed for virus spillover and infection of migratory geese on the wintering grounds" and that this pathway as a transmission route "was supported by rapid migration movements of some geese and genetic relatedness of H5N1 virus isolated from geese in Tibet and Qinghai Lake."
Mar 9 PLoS ONE study
Australian study finds trivalent flu vaccine effective against H1N1
A study of patients seen by sentinel physicians in Australia found the 2010 trivalent seasonal influenza vaccine was 79% effective against 2009 H1N1 flu. The study, a test-negative case-control approach, included 139 case-patients who tested positive for 2009 H1N1 by polymerase chain reaction and 180 controls, who had negative flu test results. The researchers found the trivalent vaccine to be 79% effective against 2009 H1N1 flu, with rates higher in adults than in children. By comparison, the monovalent 2009 H1N1 vaccine had a 47% effectiveness rate, a finding that was not statistically significant compared with no vaccine. The authors conclude, "Despite some limitations, this study indicates that the first seasonal trivalent influenza vaccine to include the pandemic (H1N1) 2009 virus strain provided significant protection against laboratory-confirmed pandemic (H1N1) 2009 infection."
Mar 9 Emerg Infect Dis study
Delaware reports Tamiflu-resistant H1N1 case
Delaware health officials yesterday said they have identified an oseltamivir-resistant 2009 H1N1 case, a 6-year-old boy from Kent County who was not hospitalized and has fully recovered. The patient is the state's first known case of oseltamivir resistance this flu season, Delaware Health and Social Services (DHSS) said in a press release. Health officials are following up on the case, which was identified during the first week of March. The respiratory specimen was part of a random sample submitted for routine antiviral testing. The boy had tested positive for the 2009 H1N1 virus in mid February. Reports of oseltamivir resistance in US patients with flu have been extremely rare this season. The US Centers for Disease Control and Prevention (CDC) said in its most recent flu surveillance update on Mar 4 that only one case had been reported at that point.
Mar 9 DHSS press release
Mar 4 CDC flu surveillance update