The gene encodes for an enzyme named EstT and is capable of “turning off” or inactivating macrolides, a class of antibiotic drugs commonly used to treat disease in cattle and other livestock.
Tylosin, tilmicosin and tildipirosin are some antibiotics classed as macrolides. Veterinarians rely on these drugs to treat illnesses in cattle such as bovine respiratory disease and liver abscesses as well as other diseases in livestock and companion animals.
With this discovery, veterinarians will know “there’s a possibility that the drug will not work because of the presence of the gene,” said Dr. Poonam Dhindwal (PhD) the paper’s lead author and a post-doctoral fellow at the Western College of Veterinary Medicine (WCVM).
Antibiotics are becoming less effective due to the global spread of antimicrobial resistance. Based on 2019 estimates, more than 1.2 million human deaths were caused by drug-resistant infections. Antimicrobial resistance genes (ARGs)—mobile genetic elements that can pass between micro-organisms—help to accelerate resistance.
The USask research team, led by WCVM assistant professor Dr. Tony Ruzzini (PhD) and in collaboration with Dr. Murray Jelinski (DVM), made the discovery after analyzing bacteria collected from watering bowls at a western Canadian beef cattle feedlot.
“[Our discovery] adds one more piece to the puzzle,” said Jelinski, a professor of large animal clinical sciences and the Alberta Chair in Beef Cattle Health at the veterinary college.
Ruzzini said scientists have previously identified the existence of this gene that’s commonly found in many animal pathogens and their microbiomes, but its purpose remained a mystery. What the USask research team discovered is that this gene can break the ring structure of the antibiotic through hydrolysis (chemical reaction caused by water).
“If you break the ring or you open the ring with water, then you disrupt the active shape of the antibiotic. So, it no longer has a high affinity for the target,” said Ruzzini.
He added that once the gene destroys the antibiotic’s structure, the drug is no longer able to work as effectively in treating an illness: “Inactivation is concerning because it reduces the effective amount of antibiotics that are being delivered during an infection.”
Ruzzini said his team found the gene in a cluster with three other ARGs—the first clue that it could be involved in antimicrobial resistance. Once the team identified the gene, team members worked to clone it and test it against a panel of many antibiotic drugs from different classes.
“This gene, even though we found it in an environmental organism, it is also present in pathogens that are responsible for causing bovine respiratory disease (BRD),” said Ruzzini. His lab has conducted numerous studies investigating BRD, which is commonly known as shipping fever.
The Saskatchewan Health Research Fund, Saskatchewan’s Agriculture Development Fund, the Beef Cattle Research Council, and the Mitacs Globalink Internship program supported the research.
Jelinski said the team’s work should be of interest to all researchers in both human and animal health fields who are studying antimicrobial resistance.
“Our finding adds to the considerable database of ARGs, which can be crossmatched to a bacteria’s DNA to determine if the bacterium has the potential to be resistant to a particular antimicrobial,” said Jelinski.
Ruzzini added that his research team is continuing to learn more about how EstT works.
“As AMR surveillance systems rely more on molecular tools for detection, our knowledge of this specific gene and its integration into those systems will help to better inform antimicrobial use,” said Ruzzini.
Some Ontario doctors have started offering a free shot that can protect babies from respiratory syncytial virus while Quebec will begin its immunization program next month.
The new shot called Nirsevimab gives babies antibodies that provide passive immunity to RSV, a major cause of serious lower respiratory tract infections for infants and seniors, which can cause bronchiolitis or pneumonia.
Ontario’s ministry of health says the shot is already available at some doctor’s offices in Ontario with the province’s remaining supply set to arrive by the end of the month.
Quebec will begin administering the shots on Nov. 4 to babies born in hospitals and delivery centers.
Parents in Quebec with babies under six months or those who are older but more vulnerable to infection can also book immunization appointments online.
The injection will be available in Nunavut and Yukon this fall and winter, though administration start dates have not yet been announced.
This report by The Canadian Press was first published Oct. 21, 2024.
-With files from Nicole Ireland
Canadian Press health coverage receives support through a partnership with the Canadian Medical Association. CP is solely responsible for this content.
ISLAMABAD (AP) — Polio cases are rising ahead of a new vaccination campaign in Pakistan, where violence targeting health workers and the police protecting them has hampered years of efforts toward making the country polio-free.
Since January, health officials have confirmed 39 new polio cases in Pakistan, compared to only six last year, said Anwarul Haq of the National Emergency Operation Center for Polio Eradication.
The new nationwide drive starts Oct. 28 with the aim to vaccinate at least 32 million children. “The whole purpose of these campaigns is to achieve the target of making Pakistan a polio-free state,” he said.
Pakistan regularly launches campaigns against polio despite attacks on the workers and police assigned to the inoculation drives. Militants falsely claim the vaccination campaigns are a Western conspiracy to sterilize children.
Most of the new polio cases were reported in the southwestern Balochistan and southern Sindh province, following by Khyber Pakhtunkhwa province and eastern Punjab province.
The locations are worrying authorities since previous cases were from the restive northwest bordering Afghanistan, where the Taliban government in September suddenly stopped a door-to-door vaccination campaign.
Afghanistan and Pakistan are the two countries in which the spread of the potentially fatal, paralyzing disease has never been stopped. Authorities in Pakistan have said that the Taliban’s decision will have major repercussions beyond the Afghan border, as people from both sides frequently travel to each other’s country.
The World Health Organization has confirmed 18 polio cases in Afghanistan this year, all but two in the south of the country. That’s up from six cases in 2023. Afghanistan used a house-to-house vaccination strategy this June for the first time in five years, a tactic that helped to reach the majority of children targeted, according to WHO.
Health officials in Pakistan say they want the both sides to conduct anti-polio drives simultaneously.
WASHINGTON (AP) — Millions of people with private health insurance would be able to pick up over-the-counter methods like condoms, the “morning after” pill and birth control pills for free under a new rule the White House proposed on Monday.
Right now, health insurers must cover the cost of prescribed contraception, including prescription birth control or even condoms that doctors have issued a prescription for. But the new rule would expand that coverage, allowing millions of people on private health insurance to pick up free condoms, birth control pills, or “morning after” pills from local storefronts without a prescription.
The proposal comes days before Election Day, as Vice President Kamala Harris affixes her presidential campaign to a promise of expanding women’s health care access in the wake of the U.S. Supreme Court’s decision to undo nationwide abortion rights two years ago. Harris has sought to craft a distinct contrast from her Republican challenger, Donald Trump, who appointed some of the judges who issued that ruling.
“The proposed rule we announce today would expand access to birth control at no additional cost for millions of consumers,” Health and Human Services Secretary Xavier Becerra said in a statement. “Bottom line: women should have control over their personal health care decisions. And issuers and providers have an obligation to comply with the law.”
The emergency contraceptives that people on private insurance would be able to access without costs include levonorgestrel, a pill that needs to be taken immediately after sex to prevent pregnancy and is more commonly known by the brand name “Plan B.”
Without a doctor’s prescription, women may pay as much as $50 for a pack of the pills. And women who delay buying the medication in order to get a doctor’s prescription could jeopardize the pill’s effectiveness, since it is most likely to prevent a pregnancy within 72 hours after sex.
If implemented, the new rule would also require insurers to fully bear the cost of the once-a-day Opill, a new over-the-counter birth control pill that the U.S. Food and Drug Administration approved last year. A one-month supply of the pills costs $20.
Federal mandates for private health insurance to cover contraceptive care were first introduced with the Affordable Care Act, which required plans to pick up the cost of FDA-approved birth control that had been prescribed by a doctor as a preventative service.
The proposed rule would not impact those on Medicaid, the insurance program for the poorest Americans. States are largely left to design their own rules around Medicaid coverage for contraception, and few cover over-the-counter methods like Plan B or condoms.
