Dec 26, 2012
Canadian outbreak showed measles vulnerability even with vaccination
Despite very high measles immunization coverage in Quebec, the province was the site in 2011 of the largest measles outbreak in North America in the past decade. A study of the outbreak, published online Dec 21 in the Journal of Infectious Diseases, found an unexpected vulnerability to illness even in recipients of a two-dose vaccination regimen. Confirmed cases in the outbreak numbered 725, with 678 of them resulting from one super-spreading importation. The index case-patient in this importation was an adult who had traveled to the Caribbean in the spring, spending several hours at the Montreal airport. This person, who had received one dose of vaccine, worked in a high school; secondary infections spread over a period of 26 weeks. Overall, adolescents aged 12 to 17 years made up 56% of the cases in Quebec. Among patients in this age-group, 22% had received two doses of vaccine; illness was milder and was associated with a significantly lower risk of hospitalization in these patients compared with unvaccinated patients and those who had received just one dose. The authors state that the Quebec epidemic "provides an opportunity for jurisdictions with a stated goal of measles elimination to reflect both on the very tight levels of population immunity required and how tenuous these levels may be."
Dec 21 J Infect Dis study abstract
UK faces typhoid vaccine shortage
International travelers in the United Kingdom are facing shortages of typhoid vaccine related to an October recall of a product made by Sanofi Pasteur, the London-based Guardian reported yesterday. The immunization is typically given to travelers free by the National Health Service, but many doctor's offices and some private travel medicine clinics have run out of doses. A Sanofi spokesman told the Guardian that its stocks of Typhim Vi are still running low and that the shortage many last through early 2013. The Guardian reported that the shortage has been exacerbated by a decision by GlaxoSmithKline, another typhoid vaccine maker, to focus on other vaccines for childhood immunization programs. So far there is no indication that the shortage is affecting patients from the United States. In October the CDC posted an announcement about the Sanofi recall on its travelers' health page noting that the six recalled vaccine lots may have lower antigen content than intended, though the company wasn't recommending that people who had received vaccine from the recalled lots be revaccinated.
Dec 25 Guardian story