After more than two years of baseline research, construction and planting, the 0.65-acre Founders Square, located at Fifth Street and Muhammad Ali Boulevard, is now an inviting public space for everyone to enjoy. However, the Trager MicroForest is more than a refreshed urban park. It is a space for scientific inquiry into the impact of intense urban greening on human health and the wider urban environment.

“The vitality of downtown Louisville is inextricably linked to the vitality of the University of Louisville and the entire metropolitan community,” said UofL President Gerry Bradley. “This beautifully renewed green space will benefit not only residents and visitors to the downtown area, it also will serve as a research site for groundbreaking investigations into the connection between trees and health by UofL researchers.”

A 30-year lease with Louisville Metro Government allows the Envirome Institute to use Founders Square as an outdoor public laboratory. In the park, UofL researchers test the physiological effects of dense planting on human health and to what extent the forest  affects temperature and humidity in the area. For Phase One of the project, the central area of the park has been densely planted with trees, shrubs and ground cover to optimize cooling and reduce urban heat.

The Trager MicroForest Project builds on the Envirome Institute’s groundbreaking Green Heart Project, which found that adding trees to a neighborhood lowered residents’ inflammation levels.

Prior to planting and construction, UofL researchers collected baseline data on how spending time in the space affects stress levels and physiological responses compared with spending time in nearby downtown areas that lack greening. In addition to human studies, the researchers are monitoring air and surface temperatures, air quality and other measures to assess the impact of densely planted trees on the environment in and around the park.

“The Trager MicroForest is part of the wider mission of the Envirome Institute to pursue knowledge about health,” said Aruni Bhatnagar, director of the Christina Lee Brown Institute. “This little forest will not only provide a pleasant space to spend time in downtown Louisville, but it will also help us test how dense urban planting can improve human health. The results of this experiment could inspire and inform the planting of microforests in cities worldwide.”

The microforest is considered part of UofL’s New Vision of Health Campus, located just across Fifth Street, which will include specially designed laboratory space to study sleep, nutrition and exercise, as well as offices and public spaces to investigate how environmental factors impact human health. The development of this innovative campus affirms UofL’s commitment to the vitality of Louisville’s urban core.

“We are excited for this project and hope to see further growth in the greening of downtown Louisville,” Michael Trager-Kusman said. “We believe having public spaces like these will only contribute to the growth of downtown Louisville.”

The park’s opening marks the completion of Phase One of the project. Planning and design for Phase Two of the Trager MicroForest will begin in late 2025. Learn more about .��

• 0.65-acre site
• 119 new trees
• 242 new shrubs
• 750 tons of new top soil
• 220 linear feet of new pathways
• 178 linear feet of retaining wall

of the official opening on May 13, 2025. View the .��

For testing, 1,100 health care workers collected their own blood and nasal swab samples and delivered them to researchers at . The samples were tested for both the presence of the coronavirus and antibodies against the virus, which indicate previous exposure. The samples were analyzed by the Center for Predictive Medicine for Biodefense and Emerging Infectious Disease (CPM) in (RBL), one of only 12 such NIH-funded laboratories in the nation and the only one in Kentucky.

In the new survey, the overall positivity rate for active infection was 0.45%, which is three times higher than the rate of 0.14% seen in 1,372 health care workers tested for the project in April and May.

“Although the overall number of positive cases among health care workers remains low, it has more than doubled from what we saw between April and May,” said UofL Assistant Professor in the Division of Environmental Medicine in the Department of Medicine Rachel Keith, who conducted the study. “The almost threefold increase in the number of infected individuals reflects a similar increase in the number of infections reported in Jefferson County over the same time period (100-200 cases in May to 500-700 in July).

A similar uptick was seen in the number of health care workers with antibodies against the coronavirus. About 2.2% of individuals tested positive for antibodies in this round, compared with 1% in April.

“Although we saw that the number of health care workers who tested positive for coronavirus antibody increased from May to July, it seems that coronavirus infection among health care workers has been lower than in the general population,” said Aruni Bhatnagar, director of the UofL Christina Lee Brown Envirome Institute. “In June, we conducted a random survey of 2,237 participants living across Jefferson County and found that nearly 4% of the general population had antibodies against the virus. In comparison, it appears that the number of health care workers infected by the virus may be half that of the general population.”

“The lower rates of exposure to coronavirus among our health care workers may be because they are more likely to wear masks, personal protective equipment (PPE) and maintain social distancing,” Keith said. “Many of those who tested positive work in areas that increase their exposure to coronavirus, such as emergency departments and intensive care units, although we cannot account for where they contracted the infection. For those that reported no known contact with COVID-positive patients or consistent use of PPE, it shows the impact that community transmission can have on essential workers.

“Strikingly, our male study population had 2.4% positivity and our female population had 1.6% positivity for antibodies. The sex-dependent positivity rates follow national trends,” Keith said.

Results from this round of testing also reveal what changes occur in the levels of antibodies in those who showed a positive antibody response in Round 1 testing.

“Of the individuals who tested positive for antibodies in Round 1 and who returned for testing in Round 2, 78.5% maintained a high level of SARS-CoV-2 antibodies,” said Krystal Hamorsky, assistant professor of medicine with the CPM at UofL, who conducted the antibody testing.

Kenneth Palmer, director of the CPM, added, “The high percentage of participants who retained antibodies suggests that there is little or no decline in the level of immunity acquired by those infected by the virus within three months and that any potential immunity imparted by the antibodies may be maintained at least for a few months.”

The Co-Immunity Project is a collaboration between the Louisville Healthcare CEO Council and the Christina Lee Brown Envirome Institute at the University of Louisville. The purpose of Phase I of the project is to test health care workers to identify those who have been exposed to the coronavirus and to determine how their body responds to the infection by making antibodies. If someone tests positive for antibodies to the virus, they may be able to donate plasma to help the sickest COVID-19 patients should they wish to do so.

Co-Immunity Project researchers plan a third round of testing for health care workers in October.

For , Round 2 testing begins in September of an additional 3,000 residents in different parts of Jefferson County to determine the existing prevalence of COVID-19 infection and antibodies in the general population. were announced in July.

This project has been made possible by the generous support of Christina Lee Brown, the James Graham Brown Foundation, the Jewish Heritage Fund for Excellence and many more.

Photo of health care workers wearing PPE .