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MELBOURNE, Australia (AP) — A regulator has approved a world-first vaccine to protect koalas from chlamydia infections, which are causing infertility and death in the iconic native species that is listed as endangered in parts of Australia.

The single-dose vaccine was developed by the University of the Sunshine Coast in Queensland state after more than a decade of research led by professor of microbiology Peter Timms.

The research showed the vaccine reduced the likelihood of koalas developing symptoms of chlamydia during breeding age and decreased mortality from the disease in wild populations by at least 65%.

The recent approval by Australia’s veterinary medicine regulator means the vaccine can now be used in wildlife hospitals, veterinary clinics and in the field to protect the nation’s most at-risk koalas, Timms said on Wednesday.

“We knew a single-dose vaccine — with no need for a booster — was the answer to reducing the rapid, devastating spread of this disease, which accounts for as much as half of koala deaths across all wild populations in Australia,” Timms said in a statement.

“Some individual colonies are edging closer to local extinction every day, particularly in southeast Queensland and New South Wales, where infection rates within populations are often around 50% and in some cases can reach as high as 70%,” Timms added.

Deborah Tabart, chair of the conservation charity Australian Koala Foundation, said resources being spent on vaccinating koalas should be redirected at saving koala habitat.

“At the risk of sounding flippant, how can anyone be so delusional as to think that you can vaccinate 100,000 animals? It’s just ridiculous,” Tabart said on Friday.

Tabart’s foundation estimates there are fewer than 100,000 koalas in the wild. The government-backed National Koala Monitoring Program estimated last year there were between 224,000 and 524,000 koalas.

“I accept that chlamydia is an issue for koalas, but I also want people to understand that they’re sick because they haven’t got any habitat,” Tabart said.

The Queensland Conservation Council, an umbrella organization for more than 50 environmental groups across the state, welcomed the vaccine. But the council’s director, Dave Copeman, echoed Tabart’s focus on preserving koala habitat.

“It’s really good news. Chlamydia is one of the key stresses that has been putting pressure on koala populations,” Copeman said.

“Koalas were at risk before chlamydia outbreaks, and they will remain at risk even if we manage chlamydia perfectly, because we keep on destroying their habitat,” he added.

Koalas are listed as endangered species in the states of Queensland and New South Wales and in the Australian Capital Territory, with habitat loss due to wildfires and urban expansion as the major threats. Chlamydia can cause urinary tract infections, infertility, blindness and death.

Treatment with antibiotics can disrupt an infected koala’s ability to digest eucalyptus leaves — its sole food source — leading to starvation, the university said in a statement.

The research has been supported by the federal, New South Wales and Queensland governments.

Federal Environment Minister Murray Watt said his government had contributed to the vaccine’s development through a 76 million Australian dollar ($50 million) Saving Koalas Fund.

“We know that koalas need help to fight diseases like chlamydia. It’s a widespread threat impacting their reproductive health and causing infertility,” Watt said in a statement.

Koalas are iconic Australian marsupials, like wombats and kangaroos. They spend most of their time eating and sleeping in eucalyptus trees, and their paws have two opposing thumbs to help them grasp and climb up tree trunks.

Australia’s wild koala populations have declined steeply in the past two decades.

Facing compounded threats from disease, habitat loss, climate change and road collisions, koalas could become extinct by 2050, according to a 2020 assessment from the New South Wales government.

Rod Mcguirk, The Associated Press

A simple fitness tracker might hold the key to revolutionizing maternal healthcare. Scientists at Scripps Research have found preliminary evidence suggesting that common wearable devices such as the Apple Watch, Garmin and Fitbit could remotely monitor pregnancy-related health changes by tracking physiological patterns-like heart rate-that correlate with hormonal fluctuations.

Wearable devices offer a unique opportunity to develop innovative solutions that address the high number of adverse pregnancy outcomes in the U.S. Our results show that signals collected via wearable sensors follow the expected changes in hormone levels and can detect unique patterns specific to live birth pregnancies, potentially allowing the monitoring of maternal health throughout the pregnancy and postpartum.”

Giorgio Quer, co-senior author, director of artificial intelligence and assistant professor of Digital Medicine at Scripps Research

The findings, released in the Lancet eBioMedicine on August 28, 2025, come at a crucial time for maternal health in the U.S. More than 2 million women of childbearing age live in maternal care deserts, or areas with severely limited access to obstetric care. Pregnancy complications, including miscarriage and preterm birth, continue to pose significant risks to maternal and child health, demanding more effective ways to monitor and address these outcomes.

Aligning heart rates and hormones

To gather the data, the team used PowerMom, a bilingual digital research platform, which allowed participants to voluntarily report real-world data from their personal wearable devices after providing informed consent-capturing valuable information beyond the traditional prenatal clinic visits. The researchers enrolled over 5,600 participants who explicitly agreed to share their data and selected 108 individuals who had consented to provide data from three months before their pregnancy through six months after delivery. Using sophisticated statistical methods to identify population-level patterns, the team could account for individual differences and device variations.

From this data, the scientists were able to identify physiological patterns that aligned with the fluctuation of key pregnancy hormones such as estrogen, progesterone and human chorionic gonadotropin (hCG). The fluctuations of these hormones are critical to healthy pregnancy outcomes and provide insight into the pregnancy’s progression.

The heart rate data was particularly compelling. During early pregnancy, researchers found that the individual’s heart rate initially decreased around weeks five to nine, then steadily increased until about eight or nine weeks before delivery, reaching peaks up to 9.4 beats per minute above pre-pregnancy levels. After birth, the heart rate dropped below baseline levels before stabilizing around six months postpartum. The researchers also tracked sleep and activity patterns throughout pregnancy.

To validate this correlation, the team compared wearable sensor patterns with published hormone-level data from previous pregnancy studies, creating detailed models that predicted heart rate changes based on expected hormonal fluctuations throughout pregnancy. While these findings are still early, they demonstrate that wearables could potentially enhance prenatal care, particularly for women living in maternal care deserts.

“Hormones play a key role in pregnancy outcomes,” explains co-senior author Tolúwalàṣẹ Àjàyí, co-senior author and principal investigator of PowerMom. “Discovering the association between heart rate and hormone changes could unlock new ways to predict the beginning of pregnancy or identify signs of adverse outcomes such as gestational diabetes or preeclampsia.”

In an exploratory analysis of a small number of cases, pregnancies ending in adverse outcomes like miscarriage or stillbirth showed different heart rate patterns compared to healthy pregnancies, though more research with larger sample sizes is needed to validate these observations.

The future of health monitoring

This research represents a significant step toward making pregnancy monitoring more accessible through technology that many individuals already own and use. By transforming consumer devices into medical monitoring tools, the approach could help bridge healthcare gaps and provide continuous oversight for high-risk pregnancies.

The digital approach builds on growing evidence that wearable devices can detect meaningful health changes much earlier. Previous work has shown their role in identifying COVID-19 infections and other health conditions through physiological pattern recognition.

The researchers plan to expand their analysis with a focus on understanding how patterns may vary across different demographic groups, geographic regions and socioeconomic backgrounds. They hope to eventually develop models that could identify birthing individuals who might benefit from additional monitoring or support.

“We want to understand if these patterns are consistent across subgroups based on age and access to care,” says first author and UC San Diego graduate student, Giulia Milan, who conducted this study in collaboration with Scripps Research. “Our goal is to determine whether this approach could eventually contribute to more personalized pregnancy care.”

Future studies will need to investigate whether physiological changes captured by wearables could potentially support clinical decision-making and patient care. The team also plans to collect both wearable data and blood samples from the same participants to directly validate the hormone-heart rate associations observed in this preliminary analysis.

Hepatitis C, a bloodborne virus that damages the liver, can cause cirrhosis, liver cancer, liver failure and death if left untreated. Despite the availability of highly effective treatments, the prevalence of hepatitis C infection remains high, particularly among women of childbearing age, who account for more than one-fifth of chronic hepatitis C infections globally. Within this group, new mothers are especially vulnerable because treatment has traditionally required outpatient follow-up appointments during the challenging postpartum period.

Now, a new study on an innovative clinical program developed by researchers at Washington University School of Medicine in St. Louis suggests that giving postpartum mothers with hepatitis C the opportunity to start antiviral treatment while they are still in the hospital after giving birth, and bringing treatment to bedside prior to discharge, significantly increases their odds of completing the therapy and being cured. The authors found that new mothers who saw an infectious disease specialist and received medication for hepatitis C during their hospital stay were twice as likely to be cured compared with mothers who got a referral to an outpatient follow-up appointment.

The findings appear Sept. 11 in Obstetrics & Gynecology Open.

We were seeing too many patients fall through the cracks simply because of traditional divisions between what was treated inpatient – labor and delivery – versus outpatient – hepatitis C. We partnered across departments to make sure that when pregnant patients come to Barnes-Jewish Hospital to deliver their babies, they have the option to also get care for a disease that, if left untreated, can lead to cancer.”

Laura Marks, MD, PhD, senior author on the study and assistant professor in the Division of Infectious Diseases in the John T. Milliken Department of Medicine

Breaking the cycle

Patients are often diagnosed with hepatitis C as part of routine screenings during pregnancy, but treatment has historically been deferred to the postpartum period. However, once women give birth, they don’t always return for follow-up care to start the medication.

To break the cycle, Marks, in collaboration with Jeannie Kelly, MD, an associate professor in the Department of Obstetrics & Gynecology and director of the Division of Maternal-Fetal Medicine & Ultrasound, implemented a “Meds to Beds” approach: Instead of referring patients with hepatitis C to outpatient follow-up care after discharge, the obstetrics and maternal-fetal medicine care team would begin the process required for an infectious disease specialist to initiate treatment before the patient was discharged.

To evaluate the effectiveness of this collaborative approach, Marks and first author Madeline McCrary, MD, an assistant professor in the Division of Infectious Diseases, reviewed medical records of 149 mothers who delivered babies at Barnes-Jewish Hospital between January 2020 and September 2023 and had tested positive for hepatitis C. Depending on the timing and availability of infectious disease specialists, the women either received immediate hepatitis C treatment while still in the hospital after giving birth or got a referral for an appointment at an outpatient infectious disease clinic or hepatology clinic after their discharge.

Overall, two-thirds of the patients who began treatment in the hospital successfully completed the full course of treatment – 2-3 months of antiviral medication – compared with about one-third of the outpatient referral group. The researchers found that over half of postpartum mothers in the outpatient referral group did not attend the follow-up appointment. The researchers measured successful treatment completion with a lab test confirming that the patient was no longer positive for hepatitis C or with a patient’s report that they had taken the full course of antiviral medication.

“Curing hepatitis C in these mothers has a huge ripple effect – it protects their health, their families and their future pregnancies,” Kelly said. “That’s why we partnered with our infectious disease colleagues to rethink how we could close the gaps in treatment. This new study shows that simply bringing the medication to the patient’s bedside right after delivery dramatically reduces the number of patients lost along the way.”

WashU Medicine’s Division of Infectious Diseases and Division of Maternal-Fetal Medicine have also partnered to integrate infectious diseases care into obstetrics clinics, including implementing new guidelines endorsing shared decision-making around treating hepatitis C during pregnancy.

Exporting the ‘Meds to Beds’ program

Marks, Kelly and colleagues are working to train doctors at WashU Medicine to deploy this interdepartmental “Meds to Beds” program, not only for postpartum mothers but for all patients with untreated hepatitis C. Since 2023, WashU Medicine doctors led by Marks have built up a hepatitis C virus care navigation and treatment program at Barnes-Jewish that incorporates the “Meds to Beds” model and arranges for expedited post-treatment follow-up in local communities to ensure patients are cured. The program has delivered medications to bedside for more than 200 patients, representing an important advance in hepatitis C care.

Beyond WashU Medicine and Barnes-Jewish, Marks points to the future exportability of the new approach, which could also be applied to other infectious diseases.

“We can’t be afraid to try a new model of care when what we stand to gain is better health for the whole community,” Marks said. “We’re teaching our trainees to treat what’s in front of them, especially communicable diseases. As they’re completing the program here, we’re seeing them get recruited to bring this successful model elsewhere. It’s a gradual process, but based on the success we’re already seeing, this momentum will continue to build over time.”

McCrary LM, Leydh Z, Curtis MR, Elrod-Gallegos J, Kojima P, Karpman L, Cain J, Vora K, Bongu J, Habrock-Bach T, Durkin MJ, Trammel C, Kelly JC, Marks L. Association between postpartum inpatient consultation versus outpatient referral with hepatitis C treatment completion. Obstetrics & Gynecology Open. September 11, 2025.

This work was supported by the Washington University Institute of Clinical and Translational Sciences grant UL1TR002345 from the National Center for Advancing Translational Sciences (NCATS) of the National Institutes of Health (NIH). The content is solely the responsibility of the authors and does not necessarily represent the official view of the NIH.

Dr. Kelly receives funding from NIDA (5R21DA057493-02, 1R61DA062321-01); NICHD (1R01HD113199-01). The funders had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

Drs. McCrary and Marks report funding from Gilead’s Frontlines of Communities in the United States (FOCUS) program. FOCUS funding supports HIV, HCV, and HBV screening and linkage to the first medical appointment after diagnosis; FOCUS funding does not support any activities beyond the first medical appointment and is agnostic to how FOCUS partners handle subsequent patient care and treatment.