Achoo! Counting the Culprits

The signs of the season, the Spring Allergy Season that is, have been painting the town yellow for weeks. Pollen, pollen and more pollen have been coating everything from cars to shoes. There are tree pollen, weed pollen, grass pollen and as many different types of them as there are blooming plants and trees, which in our climate is a lot. Trees, grasses and low-growing weeds produce small, light, dry pollen grains that can easily be spread by wind currents, which keep them airborne and can carry them over long distances. These are the pollen that trigger allergy symptoms.

If you suffer from allergies, and metropolitan New Orleans is in the top tier of cities where people are most affected by seasonal allergy symptoms, LSU Health New Orleans thinks it is important that you know what is actually in the air you breathe. If you know what pollen are out there, you can better prepare. So, every day the pollen counters at LSU Health New Orleans Pollen Counting Station, housed in the School of Medicine’s Section of Pulmonary/Critical Care & Allergy/Immunology, report what pollen and in what concentrations are present here.

It is serious business. First, the pollen counting team had to learn about pollen – all the different kinds and how to recognize them – and then demonstrate their expertise. They completed rigorous education and training and then passed a national qualifying exam to become certified. The LSU Health New Orleans Pollen Counting Station is the only one certified by the National Allergy Bureau of the American Academy of Allergy, Asthma & Immunology in Louisiana. In fact, it is the only certified station between Houston and Birmingham.

So how do they get the counts? Every morning, a member of the team prepares a slide with a special coating to which pollen grains will stick and then swaps it with the one from the day before in a piece of very sophisticated pollen collecting equipment. Its centrifuge pulls in a constant volume of air – 10 liters a minute through a slit. The slide moves across a slit in the housing at 2 mm per hour.

“After 24 hours, the slide has gone 48 mm, so the pollen grains are distributed, covering practically the whole slide,” notes Research Associate Elizabeth Porretta, team leader.

In the lab, the counters, who also include research associates Olga Nichols, Karen Eberle and Nick Lanson, stain and fix the slide. They melt gelatin glycerol and combine it with a red stain to dye the grains, keep them in place and preserve them. Under the microscope, they find, identify and count the grains, clicking a mechanical counter for each one.

At their fingertips is also a binder filled with pictures and other identifying information. They have reference slides as well. The LSU Health team of counters is even building their own reference library of pollen specific to our area like bald cypress, sweet gum, magnolia and palm.

“We plug the results of our counts into a formula that calculates how many pollen grains per cubic meter there are over the 24-hour period, and that’s the number we report,” Porretta says.

A scale determines the level of outdoor exposure – very high, high, moderate or low.

“We share our levels with LSU Health New Orleans allergists/immunologists who are treating patients, and they are also available to our researchers,” says Nichols. “We have built a pollen database that houses years of detailed information.”

The daily counts are a real help to the physicians who are treating patients, in ever-increasing numbers.

“We are seeing a lot more allergy patients than what we used to see in the past,” notes board-certified allergist/immunologist Dr. Sanjay Kamboj, LSU Health New Orleans Associate Professor of Clinical Medicine. “Up to 5-10% more.”

There is an important distinction that sets the LSU Health New Orleans counts apart.

“Having a local day-to-day pollen count based on real data is really great because it’s an accurate assessment rather than an estimated predictor,” says Dr. Michelle Korah-Sedgwick, LSU Health New Orleans Assistant Professor of Clinical Medicine. “This year, we had a really mild winter, so we actually saw pollen earlier than we would have other years.”

There’s another benefit to a real pollen count – quicker diagnoses. “Knowing what’s in or not in the air and if that doesn’t correlate with symptoms, this could indicate that a patient’s condition is something other than allergies,” adds Korah-Sedgwick, also a board-certified allergist/immunologist.

The LSU Health New Orleans pollen counting team works 7 days a week, 365 days a year. While some pollen are more numerous at certain times of the year, pollen season is pretty much year- round in our area.

In addition to sending the levels to the National Allergy Bureau, local television stations, WWL-TV, WVUE-TV - Fox 8, WGNO-TV and WDSU-TV, report them in their daily weathercasts. The Weather Channel also uses LSU Health New Orleans’ counts.

“We are providing a unique service to our community and providing valuable data to the most trusted source of accurate pollen levels nationally,” concludes Dr. Carol Mason, Chief of Pulmonary/Critical Care & Allergy/Immunology at LSU Health New Orleans School of Medicine.