COVID-19 outbreaks have proven difficult to contain throughout the pandemic, but especially so in healthcare settings.

Since healthcare workers are constantly in close contact with one another during procedures, making rounds, or even when on break, avoiding infections among medical staff is critical.

In March 2020, a large urology department in Mainz, Germany, grappled with nearly 10 percent of its employees testing positive for the novel coronavirus. The outbreak is believed to have stemmed entirely from a single infected staff member.

The experience was chronicled last month in the American Journal of Infection Control. The report traces COVID-19’s spread throughout the urology department from start to finish, looks at the effectiveness of prevention measures and surmises ways it could have been prevented.  

The Outbreak

The department’s first positive test occurred March 14, 2020. All staff members who had come into contact with the infected employee were identified and classified into three categories, from high (Category I) down to low (Category III). The seven staffers identified as Category I contacts entered a 14-day quarantine, and none developed COVID-19. Other staffers reporting symptoms also entered a quarantine period until they produced consecutive negative tests.

Masks became mandatory in the urology department two days later. Because this occurred during a national shortage of FFP2 masks in Germany, surgical masks were used when treating patients not suspected to be infected. For patients known or suspected to be infected with COVID-19, healthcare workers donned full PPE.

Four staff members tested positive in a six-day span, one of whom was later found to have had close contact with the first coworker reportedly infected. The two had performed a 30-minute procedure together three days prior to the initial positive test, with neither wearing a mask.

This employee should have been deemed a Category I contact and been made to quarantine, according to a subsequent analysis.

Five staff members tested positive for COVID-19 over the next four days. One positive test came on Day 21 and the final two on Day 24.

Every staff member was tested on Days 26 and 27. The urology department had no further positive tests until mid-November, the end of the study period.

The Fallout

The most common symptoms among staff were loss of taste and smell, with one individual yet to regain it six months after infection. Two more employees have dealt with long-term symptoms or complications.

A survey conducted later found the urology staff members infected at least seven people outside of the department, either at home or within their circle of friends.

The authors write that the study conducted shows how difficult COVID-19 is to contain within a healthcare setting. They believe the one missed close contact created the snowball effect.

The authors additionally noted a tendency of staff to remove masks during what they considered “social” settings such as breaks — which might explain the rapid viral spread.

“The fact that the lunch or break rooms on the wards were not supplied with any ventilation system other than opening windows may have contributed to the transmission," they write.