NEWS SCAN: Plague and climate change, airport scare, Tamiflu and toddlers, flu conference, H1N1 vaccine uptake

Sep 7, 2010

Climate change may lower US cases of plague
A study of 56 years' worth of climate data and plague incidence in 13 western US states (from 1950 through 2005) caused scientists to conclude that climate change may lead to fewer cases of the disease. The study, in the American Journal of Tropical Medicine and Hygiene, looked at how temperatures and precipitation patterns affected rodents and fleas, which are key carriers of the disease. It revealed that the incidence of plague in those states decreases as regional temperatures rise and snowfall decreases, a possible positive effect of climate change. The researchers, who looked at data for all 105 counties that reported a case of plague during the study period, suggested that global warming will likely result in less snowfall in western states, which lowers summer soil moisture, making survival more difficult for fleas and rodents. "We are encouraged that prevalence of the plague is decreasing, likely due to environmental factors," said one of the authors in a press release, while cautioning that "plague is still a modern healthcare concern. People should be more vigilant and monitor it."
September Am J Trop Med Hyg abstract
Sep 7 press release on the study

Plague researcher's canister triggers airport scare
A suspicious canister that a plague researcher had while going through customs upon a return trip from the Middle East triggered a bioterrorism scare at Miami International Airport on Sep 2, according to a Sep 4 Associated Press (AP) story. Airport screeners grew concerned about the metal canister, which they said looked like a pipe bomb, when they determined that the man who had it was Dr Thomas Butler, a well-known plague researcher who was the target of a federal investigation in 2003, when he reported that plague samples might have been stolen from his Texas Tech University lab. Authorities closed most of the airport overnight and awoke guests at a nearby hotel. Butler was released the next morning without charges after tests on the canister found nothing dangerous, the AP reported. In the 2003 episode, Butler was acquitted of most charges, but jurors found him guilty of mislabeling and unauthorized export of plague samples to Tanzania. He was also convicted of fraud and theft charges that stemmed from clinical study contracts with pharmaceutical companies.
Sep 4 AP story

Study shows early Tamiflu effective against flu in toddlers
Finnish researchers reporting in Clinical Infectious Diseases found that oseltamivir (Tamiflu) administered within 24 hours of seasonal influenza symptoms provided "substantial benefits" to children 1 to 3 years old. The scientists studied 408 children randomly assigned to oseltamivir (203 children) and placebo (205) groups. Of those, 79 contracted lab-confirmed influenza A and 19 had influenza B. Among those with influenza A, oseltamivir treatment started within 24 hours shortened the course of illness by 3.5 days (3.0 vs 6.5 days) in all children and by almost 4 days (3.4 vs 7.3) in unvaccinated children. It also reduced parental work absenteeism by 3.0 days but had no effect for those with influenza B. Also, when oseltamivir was started within 12 hours of symptom onset, it decreased the incidence of otitis media by 85%, but no significant reduction was seen with treatment started within 24 hours.
Sep 3 Clin Infect Dis abstract

Flu experts weigh in on vaccine production, H5N1 threat
The vaccine against the 2009 H1N1 virus helped curb the spread of influenza, but the world needs quicker and better methods of producing vaccines against future pandemic strains, a World Health Organization (WHO) official said yesterday at an international meeting of flu experts in Hong Kong, the Associated Press (AP) reported. David Wood, a coordinator with the WHO's immunization and vaccines department, told reporters that about 350 million doses were administered worldwide and that studies suggest the vaccine was protective in 95% of people who received it. He said that though the vaccine was available about 6 months after the new virus was detected, it arrived too late in some countries, such as the United States, to greatly reduce the second wave of the pandemic. Also at the meeting, flu researcher Robert Webster on Sep 5 warned against complacency amid low levels of 2009 H1N1 flu activity in most parts of the world. Webster, a virologist at St Jude's Children's Research Hospital in Memphis, Tenn., pointed out that the number of H5N1 avian flu cases rose in 2009, led by cases in Egypt, after years of declines. He said so far the virus hasn't gained the capacity to spread efficiently among humans, but viruses can change quickly. Wood and Webster made the comments in conjunction with the 12th annual Options for the Control of Influenza meeting.
Sep 5 AP story

Australian studies find low pandemic vaccination rates
Two new reviews of 2009 H1N1 vaccine uptake in Australian populations showed lower than expected rates, especially in pregnant women. The studies, conducted in Western Australia state, appeared yesterday in an early online edition of Medical Journal of Australia (MJA). The first study used a vaccination database and a surveillance system to assess pandemic vaccine uptake in Western Australians ages 10 and older from Sep 30, 2009, though Jan 31. Coverage ranged from 10.3% in pregnant women to 52.8% in healthcare workers. Rates for ages 10 and older were 14.5%, and the rates for those 18 and older were 15.3%. The authors concluded that coverage levels were similar to the national rate of 19% but didn't reach the 50% uptake needed to stop community transmission. Coverage in vulnerable groups, except for pregnant women, was higher than the general population. Researchers said public perceptions that the pandemic virus was mild and safety concerns about the vaccine could have contributed to low vaccination rates. In the second study, researchers looked at pandemic vaccine uptake in Western Australian pregnant women who sought prenatal care at a public clinic in Joondalup in January 2010. Of 476 women who were eligible to receive the 2009 H1N1 vaccine, only 33 (6.9%) had been immunized. Of the women who were not vaccinated, most (63.9%) said physicians had not offered the vaccine, and nearly 20% said their physician had advised against it. Many (61.6%) said they would have declined the vaccine because of safety concerns. The authors wrote that offering safety education about the vaccine through obstetricians and other providers could improve vaccine uptake in pregnant women.
Sep 6 MJA vaccine uptake study abstract
Sep 6 MJA vaccine in pregnant women abstract

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