Slight rise in risk of intussusception seen with rotavirus vaccine
Rotavirus vaccination in infants slightly raises the risk of a specific intestinal disorder, researchers reported today in The New England Journal of Medicine.
US investigators assessed the effect of both the pentavalent (five-strain) RotaTeq vaccine and Rotarix, a monovalent formulation, on the risk intussusception in infants 5 to 37 weeks old. Intussusception is an inversion or "telescoping" of one segment of the intestine within another segment, which can block the passage of food or fluid and cut off blood supply. It has been noted in other countries as a risk with both vaccines.
Their analyses included 507,874 first doses and 1,277,556 total doses of RotaTeq and 53,638 first doses and 103,098 total doses of Rotarix.
For RotaTeq, they found the risk of the disorder to be slightly elevated after the first dose, with an attributable risk of 1.1 excess cases per 100,000 vaccinees within 7 days and of 1.5 excess cases within 21 days in their primary analysis, and an attributable risk of 1.2 excess cases within 21 days in a secondary analysis. The primary analysis included only vaccinated children, while the secondary analysis included exposed and unexposed infants.
The secondary analysis of Rotarix suggested a potential risk, but the authors said the study of that vaccine was underpowered.
An accompanying editorial calls the risk low and says the harm prevented by the vaccine outweighs the risk: "In the US cohort of 4.5 million babies born each year, vaccination is estimated to prevent approximately 53,000 hospitalizations and 170,000 emergency department visits for diarrhea, at the expense of causing 45 to 213 cases of intussusception nationwide."
The study was funded by the US Food and Drug Administration.
Jan 14 N Engl J Med study
Jan 14 N Engl J Med editorial
More chikungunya cases confirmed in Caribbean
Three cases of Chikungunya have been confirmed in the Virgin Islands in the midst of an ongoing and widespread outbreak on nearby St. Martin and other Caribbean islands, according to a story yesterday in the Virgin Islands Platinum News.
The infected patients, all on Jost Van Dyke island, have no history of travel, meaning the illnesses were locally acquired and the virus is in the mosquito population there, an official with the Ministry of Health and Social Development said.
Surveillance in the area was stepped up after reports of the St. Martin cases. Preventive efforts are also being enhanced, including fogging in mosquito-breeding areas by the Environmental Health Division and educational efforts for residents.
People are being urged to inspect their premises for potential mosquito-breeding areas such as uncovered water containers. Other measures include minimizing personal exposure by using insect repellent and covering baby cribs with netting and contacting a physician if symptoms such as fever, headache, and joint pain occur.
Jan 13 Platinum News story
Jan 10 CIDRAP News scan on St. Martin outbreak