Malaria and the Inner Armies

On ERV, Abbie Smith writes “Malaria kills 1.24 million people a year. Mostly babies under 5 years old.” Malaria, although carried by mosquitoes, is caused by a single-celled protist which infects the liver and goes on to parasitize red blood cells. Now, a little genetic engineering could put a stop to this scourge. Smith says “Mosquitoes have a symbiotic relationship with their bacteria the same way we do—they need their ‘good’ bacteria to get all the nutrients they need to survive.” By tweaking the protein output of one such bacteria, scientists have made mosquito guts inhospitable to malaria. The test result? An 84% decrease in the number of mosquitoes carrying malaria, and a 98% reduction in malarial replication among carriers. Of course, mosquitoes aren’t the only animals that support friendly bacteria—and researchers at the Weizmann Institute are discovering that our friendly bacteria support a number of viruses. They identified hundreds of different bacteriophages “thanks to the fact that bacteria keep ‘files’ within their genome of every virus that has ever tried to attack them.” Some of these phages may confer benefits to our internal ecosystem. And humanity has 80% of them in common.


Vaccine Varieties

On The Pump Handle, Liz Borkowski examines the ethical dilemma of testing the anthrax vaccine in children. If a widespread attack were to occur, we would want to know the safety and efficacy of the vaccine beforehand. But is an attack likely enough to warrant testing the vaccine on children? On ERV, Abbie Smith explains how vaccines are made: “Sometimes we use dead viruses. Sometimes we use crippled viruses. Sometimes we dont need to use whole viruses at all—little chunks of the virus are fine. Sometimes we just need chunks of the virus, but we keep them dressed up in hollow membranes.” Sometimes none of these approaches work (against diseases such as HIV, TB, and malaria). However a new vaccine against malaria may prevent about half of infections. Other vaccines can be nearly 100% effective. Such is the case with the HPV vaccine, which the CDC is now recommending for boys as well as girls. The vaccine protects against several variants of human papillomavirus, which can cause changes in a cell’s DNA that lead to cancer. In fact, from 2001 to 2004, HPV caused 71.7% of oral cancers. Finally, on Respectful insolence, Orac considers the efficacy of the flu vaccine, which reduces the infection rate from 2.7 out of 100 adults to 1.2 out of 100. Orac writes, “our current generation of vaccines are far from perfect, but they do pretty well and, given how safe they are, currently represent the best defense we have against influenza.”