25 US States have mutant lice immune to common treatments

Researchers have come to know that mutated lice resistant to all common treatments are prevalent in most parts of the United States. However, experts are saying that there’s nothing to panic about at this moment as these findings are preliminary.

This Tuesday, Professor John Marshall Clark of the University of Massachusetts and Professor Kyong Yoon of the Southern Illinois University presented preliminary results from their research on mutant lice at an American Chemical Society meeting held in Boston.

The team conducting the study collected lice samples from a total of 30 states and discovered that as many as 25 states are home to lice boasting genetic mutations known as a knock down resistance mutations. For those who don’t know: this particular mutation type is known for helping certain insects such as house flies in surviving insecticides.

Yoon said that when the chemical is used over and over again, lice tend to develop resistance. He added that this makes it extremely important to think before using any treatment. The good news here is that head lice are not disease carriers; they are more irritating than harmful.

This particular mutation type is observed in several other insects, which can protect themselves from a range of common insecticides including the ones used for formulating the common OTC medications for lice.

Lice populations in the states in pink have developed a high level of resistance to some of the most common treatments.

The team conducting the above-mentioned research, however, didn’t study whether lice with knock down resistance mutations could actually survive common OTC treatments. What they did study was whether there has been an increase in the number of reports on drug-resistant lice in the 25 affected states.

As mentioned above, the team has only analyzed samples from 30 states. However, it has plans of looking at samples from a minimum of 18 more states before publishing the findings in the form of a paper.


Reports suggest that most experts believe that these findings are too preliminary for confidently announcing that mutant lice are resistant to all common drugs. According to Dr. Joseph Gigante of the Vanderbilt University Medical Center, more studies must be conducted for finding out whether these lice are really resistant to the common OTC drugs.

Gigante added that often when testing antibiotic resistance researchers find that although lab results indicate drug resistance, patients show response when treated with those medications. He believes the same might happen even with these small creatures.