For students, the start of the school year means new classes, new friends, homework and sports. It also brings the threat of head lice. The itch-inducing pests lead to missed school days and frustrated parents, who could have even more reason to be wary of the bug this year. Scientists report that lice populations in at least 25 states have developed resistance to over-the-counter treatments still widely recommended by doctors and schools.

The researchers are presenting their work today at the 250th National Meeting&Exposition of the American Chemical Society (ACS), the world's largest scientific society. The meeting features more than 9,000 presentations on a wide range of science topics and is being held here through Thursday.

Since the chickenpox vaccine became available in the U.S. in 1995, there has been a large reduction in chickenpox cases. Hospitalizations and outpatient visits for chickenpox have continued their decline after a second dose of the vaccine was recommended to improve protection against the disease, according to a new study.

We humans have an innate tendency to recognize patterns. This ability has helped us survive by learning important skills such as how to distinguish danger (predators and poisonous plants, for instance) from important resources (food sources and safe shelter) and knowing the right time of year to plant crops.

But the same ability can sometimes convince us we’re seeing a meaningful pattern when it isn’t there. Gamblers detect “patterns” in lottery numbers and roulette wheels, fortune tellers detect “meaning” in chance events and weave a story. As a society we carry all kinds of similar superstitions, such as “bad things happen in threes.”

Rabbits have long been considered immune to prion disease, but recently scientists have shown that they can--under certain circumstances--get transmissible spongiform encephalopathy (or TSE, the scientific term for the fatal brain disease caused by prions). Two studies address what makes rabbits hard to infect with prions and how their resistance can be overcome.

A research group has made a breakthrough discovery which could help thousands of young girls worldwide who are suffering from a rare yet debilitating form of epilepsy. The United States pharmaceutical company Marinus Pharmaceuticals is now recruiting affected girls as part of the world's first clinical trial to test the therapy. 

Professor Jozef Gecz, from the University of Adelaide's Robinson Research Institute, was a key player in identifying the responsible gene and mutations in this female-only epileptic syndrome, in 2008 and has now found a treatment for this disorder.

Flu vaccines can be a shot in the dark - they must they be given yearly and there's no guarantee the strains against which they protect will be the ones circulating once the season arrives. 

New research suggests it may be possible to harness a previously unknown mechanism within the immune system to create more effective and efficient vaccines against this ever-mutating virus.

Every time you put on bug spray this summer, you're another front in the ongoing war between humans and mosquitoes - and being a citizen scientist in a complex evolutionary experiment.

Scientists have found that between 5 and 20 percent of a mosquito population's genome is subject to evolutionary pressures at any given time, creating a strong signature of local adaptation to environment and humans. This means that individual populations are likely to have evolved resistance to whatever local selection pressures are typical in their area, and that understanding the genomes of those populations could one day help inform agencies about which pesticides are likely to be most effective against them.

The 2014-2015 flu vaccine didn't work as well compared to previous years because the H3N2 virus recently acquired a mutation that concealed the infection from the immune system. A study published on June 25 in Cell Reports reveals the major viral mutation responsible for the mismatch between the vaccine strain and circulating strains. The research will help guide the selection of viral strains for future seasonal flu vaccines.

Although we know influenza viruses circulate in temperate, populated parts of Australia every winter, predicting the precise timing and relative intensity of flu seasons is a fraught undertaking.

Children are more likely to have a repeat, delayed anaphylactic reaction from the same allergic cause, depending on the severity of the initial reaction. 

Anaphylaxis is a severe, allergic reaction that is rapid in onset and can result in death. Some children are at risk of delayed ('biphasic') anaphylactic reactions. Delayed reactions occur when the initial symptoms of allergic reaction go away but then return hours or days later without exposure to the initial substance that caused the reaction.