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Yahoo
3 days ago
- General
- Yahoo
Rare tick-borne illness moving south to Maryland, study says
A tick-borne illness typically found in the Northeast is moving farther south, and the Baltimore region is one of Maryland's hot spots, according to a study released last month. Cases of babesiosis, a rare disease most commonly spread by bites from deer ticks, are growing in Maryland and the mid-Atlantic region, according to a study published in the Journal of Medical Entomology, and so is the range of ticks infected with the parasite that causes the disease. While the idea of a new tick-borne disease to watch out for can be worrisome, researchers are aiming to ensure that residents and health care providers are informed about the illness and its growing threat in the area, especially as summer approaches. 'It's not a freak-out issue because we can diagnose it and we have a cure,' said Ellen Stromdahl, an entomologist who worked at the Defense Centers for Public Health's vector-borne disease laboratory in Aberdeen. 'It's an awareness issue.' Stromdahl was one of nearly two dozen researchers who collected and tested ticks in Maryland, Delaware and Virginia, looking for ones that carried the parasite that causes babesiosis. Less than 3% of the deer ticks researchers tested were found to be infected with the parasite, according to the study. Maryland's Eastern Shore and the Baltimore region are hot spots for ticks carrying babesiosis, the study says. Many people with babesiosis don't feel sick or have symptoms, according to the Centers for Disease Control and Prevention, but some may experience flu-like symptoms such as a fever, chills, sweating, body aches, appetite loss, nausea or fatigue. Symptoms may start a week after being infected, but typically develop over the course of a few weeks or months. The illness can be worse — even life-threatening — for older people or for those who have weakened immune systems. 'It's rare, but if it's overlooked, the consequences can be really bad,' Stromdahl said. The number of reported cases of babesiosis in Maryland remains low, though data from the Maryland Department of Health show an increase over the past decade. In 2023, for instance, there were 29 reported babesiosis cases in Maryland — a jump from seven cases in 2022 and 13 cases in 2021. Lyme disease, Maryland's most common tick-borne illness, is far more prevalent, with 2,463 probable cases reported in 2023. Some symptoms of Lyme disease can be similar to babesiosis, but the two illnesses are treated differently, Stromdahl said. Doctors generally prescribe antibiotics for Lyme disease. But if you're still sick even after taking antibiotics, it may be time to return to the doctor and ask about babesiosis, Stromdahl said. If you spend time outside in grassy, bushy or wooded areas, wear long pants and a long-sleeved shirt. When you come inside, check your clothing and body for any ticks. And if you find a tick, remove it quickly using tweezers. You can dispose of the tick by putting it in a sealed bag or submersing it in alcohol. If you're bitten by a tick, you can save it to show to a doctor, too, Stromdahl said. Have a news tip? Contact Natalie Jones at najones@
Yahoo
30-04-2025
- Health
- Yahoo
Study finds bed bugs may be genetically re-wiring to resist insecticides
Bed bugs appear to have developed a genetic resistance to some insecticides designed to kill them, according to a recent study published in the Journal of Medical Entomology. It's an evolution that may have been decades in the making, triggered by early attempts to curb bed bug population booms. In the 1950s, increasing international travel and immigration helped fuel a global bed bug infestation. In the U.S. alone, as many as 30 per cent of houses were infested. The problem was successfully controlled with dichloro-diphenyl-trichloroethane, or DDT. However, by the 1970s, manufacturers phased out DDT usage due to associated environmental and health concerns. Today, DDT is banned for most uses worldwide. In the recent paper, the authors argue that since DDT has been banned, bed bugs have steadily re-gained ground globally and display 'resistance to an array of insecticides used for their control.' The study, led by Virginia Tech urban entomologist Warren Booth and graduate student Camille Block, identifies a gene mutation in bed bugs that mirrors one known to cause insecticide resistance in German cockroaches and whiteflies. Using data from North American pest control collections from 2008 to 2022, Block analyzed a bed bug from each of 134 distinct populations. Two samples from different locations presented the nerve cell mutation observed in other insecticide-resistant insects. Because bed bug populations are typically highly inbred, one individual is generally a fair representation of its entire infestation. But to be sure, the team screened all specimens from the two affected populations. 'When we went back and screened multiple individuals from the two populations, every one of them had the mutations,' Booth said in a statement. 'So they were fixed for these mutations, and it's the same mutation that we find in German cockroaches.' The mutated gene is known as Rdl, and it has been documented in several pest species. It is associated with dieldrin, a chemical belonging to the same group of organochlorines as DDT. Dieldrin was banned in the 1990s, but Fipronil—an insecticide with the same mechanism of action—is still in use today. According to the study's authors, because Fipronil shares this mechanism, the gene mutation should, in theory, allow bed bugs to gain resistance to both pesticides. Fipronil is typically used as a flea treatment for cats and dogs and has been proven effective against bed bugs in lab tests, alongside the now-banned dieldrin. Booth suspects the way some pet owners interact with their animals may be driving this mutation. 'Many pet owners let their dogs or cats sleep in bed with them,' he said. 'If those animals have been treated with Fipronil, it could leave residue in the bedding, inadvertently exposing any bed bugs present and selecting for this mutation.' Booth says the next step is to expand upon the findings and search for the gene mutation in bed bugs in other parts of the world, as well as in different eras. That includes museum specimens—because bed bugs have scurried about Earth for millions of years. Sandy Smith, a forestry professor at the University of Toronto, told The Weather Network in 2023 bed bugs will always be near humans because they need our blood to survive. "Like all organisms, in all insects, they have an optimal range. Our household temperatures are about right for them," she said. Adult bedbugs usually live around ten months, though they can extend their longevity to a year or even more inside a hospitable home with temperatures between 21°C and 28°C. Bed bugs can tolerate the cold, but if exposed to below-freezing temperatures for several days, they will die. "We're blessed in Canada with a really cold winter," Sandy said, adding that putting your mattress outside for five days during a cold spell will kill them. They don't do well in warmer temperatures, which can cause them to become dehydrated. How do bed bugs get into my home? Bed bugs are master hitchhikers. They can enter your home through clothing or backpacks, luggage, or purses placed on upholstered surfaces. They can also come into the home through infected furniture, according to the New York Department of Health. How do I reduce the risk of bringing bedbugs home? Keep your bags or suitcases on stands when at hotels. When you return home, wash your clothes and place them in a hot dryer. How do I confirm a bed bug infestation? You can see the bugs. You may also visit their droppings, eggs, or shed skin on your living spaces. What do I do if I have bed bugs? Contact a reputable specialist with a proven track record of successful bedbug removal. Bed bug infestations can be challenging to eradicate, and professional assistance is often necessary for adequate control. *Header image credit: Piotr Naskrecki. File photo via Wikimedia, public domain. *
