Latest news with #LancetMicrobe
NBC News
09-07-2025
- Health
- NBC News
Fungal infections are getting harder to treat
Fungal infections are getting harder to treat as they grow more resistant to available drugs, according to research published Wednesday in The Lancet Microbe. The study focused on infections caused by Aspergillus fumigatus, a fungus that is ubiquitous in soil and decaying matter around the world. Aspergillus spores are inhaled all the time, usually without causing any problems. But in people who are immunocompromised or who have underlying lung conditions, Aspergillus can be dangerous. The fungus is one of the World Health Organization's top concerns on its list of priority fungi, which notes that death rates for people with drug-resistant Aspergillus infections range from 47%-88%. The new study found that the fungus's drug resistance is increasing. On top of that, patients are typically infected with multiple strains of the fungus, sometimes with different resistance genes. 'This presents treatment issues,' said the study's co-author, Jochem Buil, a microbiologist at Radboud University Medical Centre in the Netherlands. Buil and his team analyzed more than 12,600 samples of Aspergillus fumigatus taken from the lungs of patients in Dutch hospitals over the last 30 years. Of these, about 2,000 harbored mutations associated with resistance to azoles, the class of antifungals used to treat the infections. Most of them had one of two well-known mutations, but 17% had variations of these mutations. Nearly 60 people had invasive infections — meaning the fungi spread from the lungs to other parts of the body — 13 of which were azole-resistant. In these people, nearly 86% were infected with multiple strains of the fungi, making treatment even more complicated. 'It is an increasingly complicated story and physicians may have trouble identifying whether or not they are dealing with a drug-resistant fungal infection,' said Dr. Arturo Casadevall, chair of molecular microbiology and immunology at the Johns Hopkins Bloomberg School of Public Health who wasn't involved with the research. Before treating an Aspergillus fungal infection, doctors look for resistance genes that can give them clues about which drugs will work best. If someone is infected with multiple strains of the same type of fungus, this becomes much less clear-cut. Oftentimes, different strains will respond to different drugs. 'Azoles are the first line of treatment for azole-susceptible strains, but they do not work when a strain is resistant. For those, we need to use different drugs that don't work as well and have worse side effects,' Buil said, adding that some people will require treatment with multiple antifungal drugs at the same time. The findings illustrate a larger trend of growing pressure on the few drugs available to treat fungal infections — there are only three major classes of antifungal drugs, including azoles, that treat invasive infections, compared with several dozen classes of antibiotics. Resistance to these drugs is growing, and new ones are uniquely difficult to develop. Humans and fungi share about half of their DNA, meaning we're much more closely related to fungi than we are to bacteria and viruses. Many of the proteins that are essential for fungi to survive are also essential for human cells, leaving fewer safe targets for antifungal drugs to attack. 'The big problem for all of these fungal species is that we don't have a lot of antifungals,' said Jarrod Fortwendel, a professor of clinical pharmacy at the University of Tennessee Health Science Center, who was not involved with the research. 'Typically the genetic mutations that cause resistance don't cause resistance to one of the drugs, it's all of them, so you lose the entire class of drugs.' Further complicating matters, the vast majority of azole resistance in Aspergillus fumigatus stems from agriculture, where fungicides are widely used. These fungicides typically have the same molecular targets as antifungal drugs. Farmers spray them on crops, including wheat and barley in the U.S., to prevent or treat fungal disease. (The first instance of azole resistance was documented in the Netherlands, where antifungals are widely used on tulips.) Aspergillus fungi aren't the target, but exposure to these fungicides gives them a head start developing genes that are resistant to these targets, sometimes before an antifungal drug with the same target even hits the market. This was the source of the vast majority of the drug resistance analyzed in the study. Fortwendel noted that fungal resistance is increasingly found around the world. 'Basically everywhere we look for drug-resistant isotopes, we find them,' he said. 'We are seeing this azole drug-resistance happening throughout the U.S. Those rates will likely climb.' Any individual person's risk of having an azole-resistant Aspergillus fumigatus is low, Casadevall said. Infections typically affect people who are immunocompromised and amount to around a few thousand cases per year in the U.S., Casadevall estimated. While relatively uncommon, the bigger risk is the broader trend of drug-resistant fungal infections. 'The organisms that cause disease are getting more resistant to drugs,' he said. 'Even though it's not like Covid, we don't wake up to a fungal pandemic, this is a problem that is worse today than it was five, 10 or 20 years ago.'
CBC
14-04-2025
- Health
- CBC
Thinking about getting a tattoo? Here's what you should know
Tattooing services are regulated and largely considered safe, but there's a growing group of experts concerned over links between tattoo ink and allergic reactions, as well as potential associations between tattoos and certain kinds of cancer. Current evidence largely shows associations — not causation — with cancer, but experts say people should be aware that tattoos do come with a small amount of risk, even if more research is needed to determine the severity of that risk. What are the risks of getting a tattoo? Tattoos are permanent because they're formed when a needle containing ink pierces skin and deposits the pigment in the dermis — the skin's middle layer — according to Dalhousie University dermatologist Dr. Kerri Purdy. The needle being dipped into ink and then penetrating the skin increases the risk of certain infections — like mycobacterial infections — as well as introduces the possibility of spreading diseases like hepatitis and HIV. "That said, the risk is exceedingly low, with people and tattoo parlours being very careful about that," said Purdy, division head of clinical dermatology and cutaneous science at Dalhousie's school of medicine. A 2025 two-part series on tattoo-associated infections published in the Lancet Microbe found that the risk of infection ranged from study to study. In general, roughly one to six per cent of tattooed people experienced a microbial infection after receiving a tattoo, though it's not uncommon for people to experience minor skin elevation or itchiness after a fresh tattoo. Tattoo infections are often mild to moderate, with the second paper in the two-part series explaining that tattooing can lead to life-threatening infections in "rare and extreme cases." Purdy says people can develop allergic reactions to compounds present in the ink itself, once the ink makes it into our skin. Western University chemist Yolanda Hedberg's 2021 study analyzed more than 70 tattoo ink samples, finding traces of potentially harmful metals like nickel and chromium in almost all of the samples tested. Arsenic, mercury and lead all turned up in one sample each. The study samples were collected both in-person and online from vendors in Sweden, but many of the ink samples were fabricated in the U.S. and are commonly available in many countries, including Canada. The study found that 93 per cent of the inks tested violated European labelling requirements. Researchers concluded that 61 per cent of inks contained "pigments of concern," but found that the level of metal exceeded restriction limits in "only a few cases." Hedberg added that the ingredients listed on an ink bottle didn't always match up with the actual ingredients in the ink itself. Different tattoo inks also present different levels of risk, she says. For example, certain red inks contain azo dyes, increasing the allergic risk. Azo dyes are synthetic and do not occur naturally. Many are non-toxic, though some azo dyes are mutagens and carcinogens. While tattoo allergies can develop within days of inking, Hedberg says it's not uncommon for tattoo allergies to develop after several weeks or even months, rather than immediately after inking. The delay likely occurs because it takes time for the body to identify the tattoo as foreign material that needs to be removed. "Generally, you would notice an allergic reaction within three months," she said. Mild cases of tattoo allergies can be treated using topical steroid creams. More significant or swollen allergic reactions can be treated using corticosteroidal injections, while very severe reactions can require medications like prednisone, according to Purdy. What does the research show about cancer? A small number of studies have tracked a potential association between tattoos and the development of certain cancers, including melanoma and lymphoma. A 2025 study of Danish twins found that the risk of skin cancer was 1.62 times higher among people with tattoos. The study looked at twins where one sibling had a tattoo and the other didn't, comparing the health of each twin. The study sampled 2,367 randomly selected twins and a control group of 316 twins, all born between 1960 and 1996. The risk was determined for tattoos that were larger than the palm of a hand. The study identified the lack of information on sun exposure as a possible limitation. Additionally, the study didn't look at factors like how many cigarettes were smoked by study participants. Another study published in the Lancet in 2024 compared almost 1,400 people who had lymphoma to almost 4,200 people who didn't, finding that 21 per cent of the people with lymphoma had tattoos. Nonetheless, the 2024 study found an association, not direct causation. The authors concluded that more research is needed to establish causality. McGill University dermatologist Dr. Elena Netchiporouk says the core compound required to produce black ink — a compound known as carbon black — is a possible carcinogen derived in part from the incomplete combustion of petroleum products. "We know that [carbon black] has very strong proof that it can cause cancer in humans," said Netchiporouk, speaking with The Dose 's Dr. Brian Goldman. Netchiporouk — who wasn't involved in the 2025 Danish study or the 2024 Lancet study — cautioned that current carcinogenic evidence comes from research on ingesting carbon black, not from injecting it into our skin. She also said darker tattoos can also make it difficult to monitor for signs of skin cancer — especially if tattoos cover up moles. It's not clear whether the size of someone's tattoos increase their cancer risk. Netchiporouk says more research is necessary to determine the true cancer risk associated with tattoo inks. What should I do if I'm worried? Purdy recommends that anyone interested in getting a tattoo visit a reputable tattoo shop. Tattoo parlours are regulated by provincial and territorial governments in Canada, while tattoo inks are subject to cosmetic regulations under the federal Food and Drugs Act. "It is the responsibility of the manufacturer or importer to meet the requirements of the Food and Drugs Act and Cosmetic Regulations and ensure that the product they are selling is safe," Health Canada wrote in an email statement. Still, Hedberg says Canada's tattoo regulations are less stringent than Europe's rules. WATCH | Why doesn't New Brunswick have regulations for tattoo shops? Why doesn't New Brunswick have regulations for tattoo shops? 1 year ago Duration 3:16 With the popularity of tattoos growing, one New Brunswick tattoo artist is sounding the alarm over the lack of provincial regulations governing the practice. The EU banned in 2022 thousands of chemicals used in tattoo inks, which has affected certain blue and green pigments. "In Canada, you can still tattoo all colours and they are not restricted here just yet," said Hedberg. Netchiporouk says laser tattoo removal is usually a safe option. However, she notes that the azo dyes typically present in red inks can undergo transformation because they're sensitive to ultraviolet radiation, as well as laser removal. "They can transform into other chemicals in the skin, which can become more likely allergenic," said Netchiporouk. Due to the questions surrounding tattoos, Netchiporouk isn't interested in getting one any time soon.
