ldoadmin

A group of researchers, (Swei, Ostfeld, Lane, and Briggs), did a study on the western fence lizard recently that produced some interesting results. The life cycle of the tick involves three stages and three blood meals. Ticks are born without the Lyme disease bacteria. However, they may acquire it during their first blood meal (as larval ticks), their second blood meal (as nymphal ticks) or their third blood meal (as adult ticks). Lizards host up to 90% of larval and nymphal I. pacificus ticks. Western fence lizards (as well as the southern alligator lizard) are not competent hosts for Lyme disease bacteria. This means they cannot transmit Lyme disease to feeding ticks. But even better, their immune system actively kills the Lyme spirochete in ticks that feed on them. So a tick that feeds on one of these lizards will take its next blood meal without the bacteria that transmits Lyme disease. This eliminates the risk of people contracting Lyme disease from the ticks that have previously fed on the lizard and reduces the infection rate of the ticks generally in the area. You would think that the number of infected ticks would go up in the absence of the lizard that kills the Lyme bacteria. Not so. . . Find out why after the leap.

David Leiby, of the Red Cross, has declared the risk of blood transfusion for Babesia microti to be unacceptably high. Babesia microti is a coinfection of Lyme disease that is transmitted primarily by ticks. Over the past 30 years, between 70-100 cases of transfusion transmitted Babesia have been reported, with at least 12 fatalities. Although the need to screen for the parasite which lives in red blood cells is now recognized as urgent, the method of screening blood has yet to be determined and several obstacles remain before screening practices are adopted. However, according the Leiby, failure to screen is "no longer a viable alternative". The abstract to the article follows the jump. . .