Jun 2, 2011
Adjuvanted pandemic vaccines produce strong immune response in study
An oil-in-water adjuvant appears to make 2009 pandemic H1N1 and H5N1 avian flu vaccines produce a better antibody response, according to a study by US government and Novartis researchers in Science Translational Medicine. Researchers measured the strength of antibody responses in toddlers, children, and adults vaccinated with the H1N1 vaccine, as well as in adults vaccinated with an H5N1 vaccine. Both vaccines contained Novartis's proprietary MF59 oil-in-water adjuvant. The adjuvant increased the magnitude, diversity, and affinity, or binding strength, of antibodies compared with unadjuvanted vaccines. The authors wrote, "Antibody affinity . . . was significantly increased in toddlers and children who received the MF59-adjuvanted vaccine. Moreover, MF59 also improved antibody affinity maturation after each sequential vaccination against avian H5N1 in adults. For both pandemic influenza vaccines, there was a close correlation between serum antibody affinity and virus-neutralizing capacity."
Jun 1 Sci Transl Med abstract
School vaccine survey sheds light on exemptions, coverage rates
A survey of vaccination coverage among US kindergarten students found that some areas were below the US Center for Disease Control and Prevention's (CDC's) Healthy People 2020 immunization targets, and for the first time reported exemption data, which the CDC said was reassuringly low. Survey findings appear today in Morbidity and Mortality Weekly Report (MMWR). The survey includes school data from 48 states and the District of Columbia that receive federal immunization grants. The survey found that the general coverage rates for most recommended vaccines was 90% or more, but some jurisdictions were below the 95% or greater Healthy People 2020 goal. Though high levels of measles, mumps, and rubella vaccination is needed to maintain the elimination of measles, the CDC said only half of the states reported more than 95% of kindergarteners had received two doses. The CDC said monitoring vaccine exemptions is a useful tool for assessing the measles threat. Most areas reported vaccination exemptions below 1% for medical reasons and below 3% for nonmedical reasons. However, the agency cautioned that interpreting the survey's vaccine exemption findings can be difficult, because the data are aggregated, making it hard to identify geographic clusters where exemptions levels are high.
Jun 3 MMWR report
Study: Certain odor molecules evade disease-spreading mosquitoes
A research group has identified three odor molecule classes that can disrupt mosquitoes' ability to use their carbon dioxide detection system of finding human hosts, which they say could lead to new disease-fighting tools. The investigators, from the University of California (UC), Riverside, published their findings yesterday in a letter to Nature. In lab and greenhouse field tests in Kenya the group included mosquito species that have been implicated in the spread of diseases such as dengue, malaria, and West Nile virus: Anopheles gambiae, Aedes aegypti, and Culex quinquefasciatus. The three odor molecules that disrupted the insects' carbon dioxide receptors were inhibitors, imitators that can be use to lure the bugs away from humans, and blinders, which temporarily disable the receptors. Dr Anandasankar Ray, a molecular biologist at UC Riverside who led the study, said in a press release that the carbon dioxide devices currently used to trap mosquitoes are expensive and bulky. "Odor molecules that mimic carbon dioxide activity, on the other hand, can lead to the development of small and inexpensive lures to trap mosquitoes – a great benefit, especially to developing countries," he said. The study was supported by grants from the Bill & Melinda Gates Foundation and the National Institute of Allergy and Infectious Diseases.
Jun 1 Nature letter
Jun 1 UC Riverside press release
MRSA found in fire stations
Environmental sampling revealed methicillin-resistant Staphylococcus aureus (MRSA) in 4% of samples at fire stations, according to a new study. University of Washington researchers swabbed medic trucks, fire trucks, and various living spaces at two fire stations. They also collected nasal samples from 40 healthy firefighters from 13 stations to assess MRSA carriage. They isolated both hospital-based and community-based MRSA from 44 of 1,064 samples (4.1%). Sites most likely to harbor the pathogen were medic trucks and kitchens. In addition, 30% of the nasal cultures were positive for MRSA (9 samples) or other S aureus strains (3 samples). Of these, 58% were genetically linked to environmental samples, suggesting surface-to-human transmission. The authors conclude, "Fire personnel interact with both hospital and community population as part of their job and thus have the potential for exposure to MRSA from both sources."
June Am J Infect Control abstract
Jun 1 Elsevier press release on the study