Decline of testing, sequencing could hinder search for future COVID-19 variants, experts warn

Reported testing levels are now at their lowest point in eight months, with reported test numbers dropping by nearly 75% since the beginning of the year.

Throughout the COVID-19 pandemic, disease surveillance efforts that rely on testing and variant sequencing have been critical tools in the global efforts to fight the virus.

Without these tools, experts said, the spread of COVID-19 could have been exponentially greater, potentially resulting in many more deaths.

"Testing and sequencing have been critical to understanding where the virus is and how it is evolving. This is critical information for response and mitigation efforts," Dr. Rebecca Katz, professor and director of the Center for Global Health Science and Security at Georgetown University, told ABC News.

Surveillance tools have helped health officials make important recommendations throughout the pandemic -- including the decision to green light booster doses for extra protection, and decision to pull back on some monoclonal antibody treatments authorized for COVID-19, following concerns that it was not effective against certain variants.