Speed matters in public health. When China reopened its borders in January 2023 and European governments scrambled for surveillance capacity, the question was not just whether airport wastewater surveillance was a good idea — it was whether it could be stood up fast enough to matter.

Berlin Brandenburg Airport (BER) provided a direct answer. In a 13-week operational period in early 2023, researchers there built and ran a functional wastewater surveillance system at an active international airport — from initial protocol development to quantified, sequenced results [1]. The experience revealed both what can be accomplished quickly and what requires sustained, long-term investment.

What they built

The BER system targeted airport wastewater rather than individual aircraft — sampling from the airport's main collection infrastructure rather than the lavatory holding tanks of specific flights. This is a simpler and faster approach to implement than aircraft-specific sampling, and it produces an ambient signal from the entire airport's passenger load rather than flight-by-flight data.

Within the 13-week study period, researchers:

  • Developed airport-specific sample collection and preservation protocols
  • Validated RNA concentration and extraction workflows on the airport matrix
  • Established RT-qPCR detection and quantification for SARS-CoV-2
  • Achieved whole-genome sequencing quality sufficient for variant identification

The system worked. SARS-CoV-2 RNA was successfully quantified and sequenced from BER airport wastewater. And critically, the sequencing revealed mutations not yet observed in Germany's clinical surveillance data [1] — the early-warning potential was real, not theoretical.

The honest challenges

The researchers were candid about the difficulties. Airport wastewater presents several operational challenges that differ from municipal WBE:

Irregular flow patterns. Unlike municipal sewage systems, which receive relatively continuous waste flows, airports have highly variable throughput — surge periods around international departures and arrivals, quiet periods overnight. Sampling strategies need to account for this variability.

Variable matrix composition. The concentration of toilet disinfectants in airport wastewater varies based on how recently lavatory service vehicles have discharged, what chemical formulations are in use at any given time, and which aircraft have been serviced recently. This chemical variability affects RNA stability and PCR performance unpredictably.

Distinguishing aircraft wastewater from terminal wastewater. Airport wastewater is a mix of waste from aircraft lavatory service discharges and waste from the airport building itself — terminals, restaurants, offices. Disentangling the two signals is methodologically challenging, especially when aircraft-specific sampling is not practical.

Protocol validation time. The 13 weeks included the time needed to validate new protocols on an unfamiliar matrix. In a crisis, this timeline compresses — but it cannot be eliminated. Protocol validation is not optional.

The funding lesson

The BER researchers make an argument that every health ministry should hear: short-term programs undermine the very purpose of surveillance [1].

A wastewater programme that runs for 13 weeks generates a snapshot. A wastewater programme that runs for three years generates a trend. Trends are what allow surveillance to distinguish between a new variant arriving and existing variants fluctuating. Trends are what allow the system to detect slow-moving threats before they become acute. Trends are what allow the data to mean something beyond the moment.

The authors recommend sustained, multi-year funding commitments as a prerequisite for any national airport wastewater programme, alongside standardized protocols that allow data to be compared across sites and over time.

The 13-week model as a launch template

Despite the challenges, 13 weeks from standing start to operational results is a significant achievement. For Thailand, it suggests that a fully operational aircraft wastewater surveillance system at Suvarnabhumi is not a multi-year infrastructure project before it can produce data — it is a matter of months, given the right institutional commitment, laboratory partnership, and protocol preparation.

AWSS brings pre-validated aircraft-specific protocols, not the airport wastewater approach of the BER study, but the timeline principle holds: a well-prepared program with experienced partners can move from agreement to first results in weeks.