Mar 19, 2012
Study: Pertussis immunity not long-lived in vaccinated adolescents
The current schedule for immunization with acellular pertussis vaccine is insufficient for prevention of pertussis outbreaks in adolescents, say the authors of a study in Clinical Infectious Diseases. The authors, from Kaiser Permanente Medical Center, San Rafael, California, identified 171 patients, 132 of them children, with polymerase chain reaction tests positive for Bordetella pertussis from Mar 1 through Oct 21, 2010, during a large pertussis outbreak in their state. Patient records were analyzed for demographic and vaccination status. Pertussis vaccination rates were found to be about equal in the study group and in controls. The rate of pertussis testing was found to be highest in infants and to then stay constant till age 12. Positive test results were lowest in children aged 0 to 6, with a notable increase in those 8 to 12. Overall, vaccine effectiveness for ages 2 to 7, 8 to 12, and 13 to 18 was 41%, 24%, and 79%, respectively. The authors suggest that earlier or more numerous booster doses of acellular pertussis vaccine be considered as part of routine immunization or for outbreak control.
Mar 15 Clin Infect Dis abstract
Massachusetts eider ducks harbor new virus
Eider ducks, a fairly common seabird, have been dying by the hundreds or even thousands during the past six falls on Cape Cod, Massachusetts, according to the Cape Cod Times. The dead animals do not appear ill or emaciated. An investigation carried out by researchers from Tufts Cummings School of Veterinary Medicine, Bosto; the University of Georgia–based Southeast Cooperative Wildlife Disease Study Group, Athens; and the National Wildlife Health Center, Madison, Wisconsin, found evidence of a new virus during necropsies of the birds. The virus, named the Wellfleet Bay virus after the Cape Cod area where the die-offs are occurring, attacks the liver and gallbladder and runs a fast course. The disease so far appears to be confined to eider ducks that summer in Maine and winter in or near Wellfleet Bay. The researchers believe the virus to be related to viruses in the little-understood Quarjavirus family, which are spread by ticks to nesting birds.
Mar 10 Cape Cod Times article