Alberta Taps Wastewater for Measles Detection Amidst Growing Outbreak

Scientists Monitor Sewage for Early Virus Warning Signals

As Alberta grapples with a surge in measles cases, researchers are now turning to the province’s wastewater systems as a potential early warning tool for the highly contagious disease.

Wastewater Surveillance Expanded

The current measles outbreak, which began in March, has seen 1,323 confirmed cases by Tuesday midday. Building upon the provincial COVID-19 wastewater surveillance program, a dedicated test has been developed to detect both wild measles virus and vaccine-related shedding in sewage samples. This initiative aims to provide a population-level understanding of measles activity.

“Wastewater surveillance was shown to be very useful globally — internationally — during COVID-19,”

—Dr. Bonita Lee, Co-lead, pan-Alberta Network for Wastewater Monitoring

Weekly samples are collected from 12 treatment plants across Alberta and sent for analysis. Researchers began testing for measles in early April, shortly after the first Edmonton cases were reported, utilizing existing infrastructure and without additional funding. These initial findings indicate significant and increasing measles activity throughout the province.

Potential for Earlier Detection

Experts widely believe the official case count for measles in Alberta underestimates the true spread. The provincial government acknowledges that cases may go undetected, particularly in heavily impacted areas. Wastewater monitoring could prove most valuable in these regions, offering public health officials a clearer picture of the outbreak’s scope.

“It’s never useful by itself. It will always be useful as a supplementary surveillance tool,”

—Dr. Bonita Lee, Professor of infectious diseases, University of Alberta

The incubation period for measles can extend up to two weeks. This timeframe raises hopes that wastewater monitoring, proven effective for SARS-CoV-2 in identifying peaks one to two weeks before case numbers rose, could provide an earlier detection method for measles. Such early insights could enable public health officials to implement timely interventions.

“I believe measles is going to continue — probably getting worse and worse,” stated Dr. Xiaoli Pang, a retired virologist instrumental in developing the provincial lab’s SARS-CoV-2 wastewater monitoring technology and the measles test. “Our wastewater plays a very important role. So we really need to continue.”

To establish a robust correlation between wastewater signals and confirmed cases, further research requiring access to clinical data is necessary. More frequent sampling, moving beyond the current weekly schedule, would also be essential for effective real-time monitoring.

Measles is a serious illness, capable of causing severe complications such as pneumonia, brain inflammation, premature birth, and death. The majority of Alberta’s current cases involve unvaccinated individuals, with over 100 Albertans hospitalized this year due to the disease. Researchers have shared their preliminary findings with provincial health officials, who are reviewing the data’s relevance to the ongoing outbreak.

Looking ahead, Dr. Pang emphasizes the vital role wastewater surveillance can play in identifying and combating emerging pathogens, potentially flagging the next pandemic threat. “Something may be new coming. If something really causes a huge problem in the near future, I think wastewater [will] play some kind of important role,” she commented. “Wastewater we see as a really important complementary tool, especially for pandemic preparation.”