A rapid spike in cases of a potentially deadly, drug-resistant fungus has concerned public health officials across the country. But a team of researchers from southern Nevada hope their new study applying sewage monitoring can help health officials get a head start on this emerging global public health threat.
The problem of pathogens
White ears is a fungus that can cause serious infections, especially in patients who are immunocompromised, who have pre-existing medical conditions, who are in long-term care facilities, or undergoing treatment with invasive medical devices such as a catheter. Infection prevention and control is difficult because the fungus can grow on dry and damp surfaces such as furniture, doorknobs, clothing, and medical equipment in healthcare settings. It has also shown resistance to many commonly used surface disinfectants and all three types of antifungal drugs. More than 1 in 3 patients with C. ear infections – which can affect the blood, heart or brain – die.
Additionally, Nevada, one of six states that have recently suffered heavy C. ear – last year, outbreaks broke out in multiple healthcare facilities and saw the highest number of fungal infection cases in the United States. The Silver State has seen a 16-fold increase, from just 24 cases in 2021 to 384 cases in 2022, according to the Centers for Disease Control and Prevention (CDC). Cases have also been reported in dozens of other countries.
what they found
A research team led by Casey Barber, a doctoral candidate at UNLV’s School of Public Health and a graduate intern at the Southern Nevada Water Authority (SNWA), recently published a study in the journal Environmental science and technology which analyzed 10 weeks of sewage samples from seven sewage ponds in southern Nevada.
Scientists have detected the genetic material of C. ear in at least one untreated wastewater sample from every wastewater treatment facility in southern Nevada and nearly 80% of all untreated wastewater samples in the study. Sewers serving healthcare facilities involved in the outbreak also showed higher detection frequencies for the fungus. The researchers noted that no fungi were detected in samples of untreated sewage from a sewage treatment facility in Utah, a region without C. ear case at the time. The fungus has not been detected in the Las Vegas Wash, which contains treated sewage effluent, or in Lake Mead, indicating that there are no signs that C. ear poses a risk to drinking water.
“These results show that wastewater monitoring can help monitor the spread of C. ear and might serve as an early warning system for public health action,” Barber said.
Other takeaways
The first human case of C. ear was reported in 2009, but has become more common in recent years. The fungus is often spread via contaminated surfaces or skin-to-skin contact with infected people, including those who are asymptomatic.
Scientists have called the Southern Nevada mushroom outbreak — which erupted in August 2021 and has now affected more than 30 healthcare facilities — one of the largest recent outbreaks of C. auris associated with state healthcare. -United. The research team officially launched C. ear-specific monitoring and data collection at the end of June 2022, as part of a larger ongoing collaboration on monitoring UNLV wastewater with SNWA.
In addition to the large-scale implications C. ear detection and prevention, the researchers said the study is groundbreaking in its progress toward establishing new procedures for the treatment, preparation and analysis of wastewater samples for research C. ear.
According to them, wastewater monitoring might provide a more accurate estimate of C. ear prevalence than traditional methods of public health surveillance, in part because traditional methods may not accurately identify C. ear leading to delays in targeted response measures. The team also anticipates that their previously established approach to monitoring levels of COVID-19 in wastewater might be applied to monitoring mutations and new strains of C. ear.
“Detection of White ears through sewage monitoring has already prompted expanded screenings in southern Nevada healthcare facilities in an effort to prevent larger outbreaks,” said SNWA Senior Research Microbiologist Daniel Gerrity. “This demonstrates how wastewater monitoring can be applied to emerging public health threats beyond COVID-19.
