November and December 2024

Have you ever wondered how scientists and doctors can test for dangerous diseases without getting sick?

Tarrant County Public Health operates a bio-laboratory that tests for some of the most hazardous microbes and substances on the planet. It’s official name is the North Texas Regional Laboratory (NTRL).

Our NTRL Director, Dr. R.P. Nilsson, operates what is called a BSL-3 lab. BSL means “bio safety lab.” The safety levels run from one, which is the lowest, to four, which is the highest.

NTRL’s safety measures allow it to confidently – but carefully - handle diseases as dangerous as tuberculosis, yellow, fever, and West Nile virus. The scientists provide accurate information about testing samples without getting sick themselves or allowing the organism to escape the laboratory.

BSL-4 lab scientists utilize positive pressure suits to handle the most dangerous microorganism such as the Ebola virus. There are 13 BSL-4 labs in the United States. Two are in Texas.

Tarrant County's BSL-3 lab tests all of the public water systems that service Tarrant County residents. It also tests the dairy farms in 36 counties, including Tarrant County, to ensure safe drinking milk.

During the summer months, we process mosquito traps to test for the presence of West Nile Virus in our mosquito population. Our entomologists separate female from male mosquitoes using a microscope and very fine instruments. Female mosquitoes are then processed in our DNA extractor, which can detect West Nile or other viruses such as St. Louis Encephalitis Virus. Both can be deadly.

The NTRL checks samples for HIV and other sexually transmitted diseases such as syphilis. The lab is an important piece of the healthcare machinery that puts downward pressure on the spread of these very serious diseases.

Sleep well tonight, knowing that Dr. Nilsson and his intrepid team of microbiologists are keeping us healthy.

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