25. June 2010 00:48
"A large polio outbreak in Tajikistan - Europe's first in years - has the potential to further spread the dangerous virus to other regions of the world, the [editors of] the Canadian Medical Association Journal [CMAJ] warned Wednesday" in an editorial appearing in the journal, the Canadian Press reports.
The CMAJ editors "suggested the outbreak, the largest since 2005 in a country where polio is not endemic, serves as a reminder that until polio is eradicated, the risk of renewed spread remains," the news service adds (Branswell, 6/23).
"There is no cure for polio, which can cause paralysis in a small percentage of infected children and adults," the Globe and Mail writes. "But the disease is entirely preventable through vaccination, which has helped eliminate it from many countries around the world," the newspaper reports (Weeks, 6/23).
CBC News, also reporting on the CMAJ editorial, notes the progression of the polio outbreak in Tajikistan, which grew from seven polio cases confirmed in children in April to more than 560 cases, including "183 that were lab confirmed" (6/23).
"'In all countries certified as polio-free, including Canada, the Tajikistan outbreak should be clanging alarm bells,' Dr. Noni MacDonald, the journal's public health editor, and editor-in-chief Dr. Paul Hebert wrote with the journal's advisory team," the news service writes (6/23).
The outbreak reflects "growing complacency over the need to vaccinate against the highly contagious disease, Hebert said in an interview," the Globe and Mail reports in a piece that examines how dips in vaccination rates can lead diseases to become reintroduced to a population (Weeks, 6/23)."To minimize risks worldwide, we must first control the outbreak in Tajikistan and its surrounding area. With help from WHO, sequential mass polio vaccine campaigns are already under way in Tajikistan," the authors of the editorial (.pdf) write. "Other countries need to step up their vaccination rates so the overall rates exceed 90% in all communities. Worldwide surveillance for acute flaccid paralysis should be enhanced to ensure rapid early detection of spread from Tajikistan" (MacDonald/Hebert, 6/23).
"The Tajikistan outbreak is the latest in a string of setbacks for the global polio eradication initiative, the 22-year-old campaign aimed at permanently stopping the spread of the disease," the Canadian Press continues. "The campaign, jointly run by the World Health Organization, Rotary International, the U.S. Centers for Disease Control and UNICEF, has to date spent $8 billion trying to achieve the goal." The article notes that Afghanistan, India, Nigeria and Pakistan are the "[o]nly four countries remain on the list of nations that have never interrupted spread of polio."
The article includes comments from John Spika, director general of the Public Health Agency of Canada's Centre for Immunization and Respiratory Infectious Diseases, and Bruce Aylward, head of the WHO's polio eradication team.
Meanwhile, the Russian Health and Social Affairs Ministry recently confirmed seven cases of polio that "it says likely originate from an outbreak in Tajikistan more than one month ago," Radio Free Europe/Radio Liberty reports. "They are the first cases of polio in Russia in 15 years," according to the news service (6/23).
Low-Dose Polio Injectable Polio Vaccine As Effective As Full Dose, Study Finds
"Giving just one-fifth the usual dose of the polio vaccine may protect babies against the virus nearly as well as a full dose, as long as it is injected just beneath the skin," according to a study published Thursday in the New England Journal of Medicine, Reuters reports. "The findings could bring down the cost of immunization, an important consideration in developing countries, some of which have had trouble containing the paralytic disease," according to the news service.
For the study, which involved 373 children from Oman, researchers used a needle-free jet injector device "to deliver the vaccine beneath the skin at ages 2, 4 and 6 months. Blood tests showed more than 95 percent of the infants mounted an effective immune response against polio," the news service writes. Though infants who received the lower dose of the vaccine produced fewer antibodies against polio, the response was sufficient to offer infants protection against the disease (Emery, 6/23)."Our study shows that intradermal administration of a fractional-dose inactivated poliovirus vaccine could serve as a dose-sparing strategy
when used in a primary routine vaccination schedule in which doses are administered at 2, 4, and 6 months of age," the authors of the NEJM study write (Mohammed et al., 6/24).
"The injectable vaccine costs about $3 per dose," Reuters continues. Though "[t]he oral polio vaccine is much cheaper, at about 15 cents, … it contains a weakened virus that can mutate and sometimes cause polio in patients or when it gets into sewage," which has led health experts to "favor the injectable vaccine," according to the news service.
"With this study, we know we can use this means to lower the price," study co-author Roland Sutter of the WHO said. "If we can do one-fifth the dose, we can at least get it down to one dollar, so we are getting into the neighborhood of a price that may be affordable for developing countries in the future."
The article includes information about the global challenges to eradicating polio and the WHO's polio eradication program, a topic touched upon in an accompanying commentary piece also featured in the New England Journal of Medicine (6/23).