Open-loop vs Closed-loop as it applies to tick-borne diseases

There is currently a very strong bias in favor of "closed-loop" feedback system and a strong bias against "open-loop" systems.

The case in favor of closed-loop feedback control systems is seductive. Computational power is so cheap it is almost free. Sensors are inexpensive and robust. A closed-loop system can be very economical to run because corrective actions are only activated when needed.

But there are some situations where an open-loop system is the proper tool and I will try to give an example and explain why.

Ticks

Ticks are vectors for many diseases.

Ticks can make you allergic to red-meat. Can you imagine life without steak???

Ticks are not very efficient at injecting disease organisms into human bloodstreams compared to mosquitoes, for instance. According to "experts" a tick must be embedded for 36 hours for transfer to be likely.

A fully engorged, adult, female tick is approximately three times the size of a raisin. People tend to notice them and deal with them before a day-and-a-half has gone by.

The nymphs, or the juvenile stages are a much greater concern and the nymphs are approximately the size of a particle of ground, black pepper or a tiny flake of dandruff. They are tiny!!!

Attempts to use smart-phone photos and QR codes to track tick-related risk has not worked very well. The nymphs are so very tiny that even phones with super-macro modes have a difficult time finding the proper plane-of-focus and creating a photo with enough detail to be useful.

The entire premise of a closed-loop control system is that the "state" and "change-in-state" can be quickly and accurately ascertained and appropriate countermeasures activated in a timely way. Having a half-dozen nymphs embedded in the skin around your ankle is not something that grabs your attention nor are you likely to notice an increase from three-to-six-to-fifteen.

That leaves "open-loop" control as the only viable option.

What might that look like?

Tick egg masses tend to be in low vegetation like grass and ground-cover.

Mice like tall grass as it provides them with cover from raptors (hawks and owls), fox, cats and other predators.

One simple strategy would be to BURN the tall grass in fence rows, ditches and around your yard in late-winter/early-spring to kill tick egg-masses, ticks waiting to latch and to destroy prime mouse habitat.

Burning used to be very common but ecological thinking is a bit like "fashion", it is subject to change. Tick-borne diseases used to not be nearly the problem they are now. I wonder why.

So, you might ask "Why can't I just mow?"

The answer would be that mowing is just hell on snake populations. And guess what most large snakes eat? Yep; rodents. Burning off the dead grass at the end of winter when the snakes are hibernating in stone-piles is reptile-neutral.

Another open-loop strategy is to be aggressive in treating your pets with tick-killing pesticides. Zeus, our German Shepherd is going to get his three-month Bravecto tablet tomorrow. That will take him through the highest risk portion of tick season and will eliminate him as a link in the ticks' life-cycle.

If the material of the gaiter is not absorbent, a headband or "scrunchie" can be added and sprayed with suitable insecticides.

Since humans are also potential food sources, a simple, open-loop action would be to wear insecticide-treated gaiters during peak tick season. The good news is that nymphs have a very high surface to volume ratio so they absorb lethal doses of insecticides very quickly.

While gaiters might look very nerdish, you will be ahead of the curve. According to Professor Jean Tsao of the Michigan State University Department of Fisheries and Wildlife, it is very common to see bird-watchers at prime sites wearing gaiters. Bird-watchers tend to be WAY ahead of the curve. They are very observant and tend to have fairly high discretionary incomes.

Professor Tsao was tasked with spearheading outreach to Michigan's outdoors people and making us more aware of the risk of tick-borne diseases.

Finally, we have too many deer in Michigan. If you are a hunter, please do not hesitate to harvest a mature doe.