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Lyme disease is a bacterial infection that is transmitted through a tick bite. It causes a round rash and can cause flu-like symptoms, but usually improves with antibiotics within weeks or months. In the picture: tick population
Lyme disease could be a thing of the past as scientists believe they will soon be able to stop ticks that transmit the bacterial infection.
US experts have found a way to manipulate the genes of the spider-like creatures that feed on blood.
It opens up the possibility for researchers to alter parts of a tick's DNA that helps them carry and transmit the disease-causing bacteria.
And the discovery could pave the way for releasing genetically modified ticks that cannot transmit disease into the wild.
A similar tactic has already been used in experiments against mosquitoes to curb the spread of malaria and dengue fever.
The approach involves using CRISPR/Cas9, which works like DNA scissors that are typically injected to edit genes.
It was thought impossible to use this technology on ticks because their eggs are coated in a hard wax that injections cannot penetrate.
But now a team at the University of Nevada has found a way around it by removing the maternal organs that make the wax without rendering the eggs useless.
They were therefore able to inject tick eggs and the gene editing tool was able to change the DNA in two places.
The results, published in the journal iScience, showed that it worked in about one in seven cases.
Another method – in which mothers were injected directly with CRISPR/Cas9 – was slightly less successful. But the team said the world-first results proved it was possible to genetically manipulate ticks, and not just by sticking to one method.
Professor Jason Rasgon, an epidemiologist at Penn State University and developer of the technology, said: “Ticks are a formidable enemy of public health.
“We urgently need new tools to combat ticks and the pathogens they spread.
“The (two gene editing) methods can be used to develop new disease control methods and also to better understand the biology of ticks.”
Lyme disease is a bacterial infection that is transmitted through a tick bite. Although not all ticks - which lurk in forests and grassy areas - are carriers of the bacteria.
It causes a round rash and can cause flu-like symptoms, but usually improves with antibiotics within weeks or months.
However, some people develop symptoms such as fatigue, pain and loss of energy that can last for years.
There is currently no vaccine and existing antibiotic treatments are not always effective.
Around 900 cases of Lyme disease are reported in the UK each year, but the true number is estimated to be around 3,000. In the USA the numbers are up to 30 times higher.
Dr. Monika Gulia-Nuss, co-author of the study, said: “Despite their ability to capture and transmit a range of debilitating pathogens, research on ticks lags behind other arthropod vectors such as mosquitoes, largely due to challenges in applying available genetic and molecular tools.
"To date, no laboratory has shown that genome modification in ticks is possible. Some have considered this to be too technically difficult to achieve.
“This is the first study to show that genetic transformation in ticks is possible using not just one, but two different methods.”
Other tick-borne diseases include babesiosis, which infects and destroys red blood cells, and the tick-borne encephalitis virus, which attacks the central nervous system.
Only a handful of cases of each have been detected in the UK so far.
Both cause flu-like symptoms, but immunocompromised people can become more seriously ill and die.
Ticks can also transmit bacteria to wild and domestic animals.
Experts warn that climate change is allowing tickets to spread to new areas, putting more people and animals at risk of infection.