One of the most uncomfortable of the Greek myths is that of Io, the maiden who was loved by Zeus until either he or is wife, Hera (depending upon which version you pick), turned her into a cow and sent her off to Asia Minor accompanied by a fly that spent most of its time biting her about the flanks.

He bugged her, you might say.

This might get you ready for summertime life among the trees and bushes of America, where the gentle and sweet rewards include roses and honeysuckle and the not-so-benign include mosquitoes, gnats, hornets, ants, ticks and the kind of flies that made Io's travels so difficult.

There are two main kinds of insect trouble in the Washington area: annoyances and threats.

The annoyances include mosquitoes, biting flies, gnats and garden-variety ants. The threats include bees, yellowjackets, wasps and ticks.

Mosquitoes are mainly an annoyance and rarely a threat to life in this area, says Patricia Randall of the National Institute of Allergies and Infectious Diseases. Sure, exotic mosquitoes carry malaria, but not in this country, and some kinds carry forms of encephalitis, but that hasn't been a big problem here.

In the case of the annoyances, you can do a lot to make life a little easier. For one thing, mosquitoes don't require a swamp for their breeding grounds. They can, and do, lay their little eggs in, say, a garbage can lid that was left upturned in the rain days ago and has less than an inch of water in it. So making sure you don't provide this kind of lying-in nest for the hummers could eliminate a source of irritation for your entire neighborhood.

Besides watching out that you don't contribute to mosquito reproduction, you can protect yourself from them -- and from other annoying bugs -- with a good insect repellent. That's one of the major breakthroughs in consumer technology (after vacuum-packed peanuts) of the postwar period. The active ingredient in the good ones today is DEET, or diethyltoluamide, which confuses the bugs and keeps them away.

Repellents range from a lotion made of 100 percent DEET to sprays of around 35 percent, and a mountain hiker with close-fitting shirt and trouser cuffs and good shoes and socks (no sandals, please), with lotion lightly applied at wrists, throat and ankles and a hat sprayed with Cutter's or Ben's 100 or the newest 100-percent repellent, Jungle Juice, is fairly safe from the irritating variety of bugs.

One summer hiker who spent a lot of time on the Great North Mountain in Hardy County, W.Va., reported using Cutter's spray and walking across a pasture/meadow with the feeling of being inside -- at a safe distance -- a bubble of gnats.

The repellents also work against wood ticks, carrier of the dreaded Rocky Mountain spotted fever and recently identified Lyme disease, but not against the order of insects called Hymenoptera, including honey bees, which get mad sometimes, like all of us, and will kill you if you aren't careful.

Any reaction to any insect sting is characterized by local pain, redness, swelling, itching and warmth at the site of the sting, all lasting up to a few hours, according to NIAID. If there are multiple stings, a toxic reaction can result, causing muscle cramps, headache, fever and drowsiness, and 500 stings within a short time are considered enough to kill. That's the kind of stings you get when you bumble into a hornets' nest or beehive.

Another kind of sting reaction, the allergic reaction, is often dangerous and often sometimes fatal. It produces some of the same symptoms as the lesser reactions, but can be triggered by a single sting, since the human involved has been sensitized -- perhaps by a sting received so long ago that it had been forgotten.

Every sting, the NIAID says, should be treated as potentially fatal and watched closely for several hours.

The allergic reaction may involve local swelling, with itching and a few hives. A systemic allergic reaction will involve spread of hives far from the sting, a feeling of being "under par" and anxious, plus edema far from the sting, sneezing, chest constiction, stomach pain, dizziness and nausea. The most severe cases may include labored breathing, difficulty in swallowing, hoarseness and thickened speech, weakness, confusion and feelings of impending doom.

Shock, coma and death can ensue. And the onset of all this can be several hours to two weeks after a sting. Rescue squads, firefighters and paramedics know how to deal with this, and do, and anybody with feelings described above after a bee sting should get to a hospital emergency room immediately.

Those with a known allergy should wear a Medic Alert piece of jewelry, in case of unconsciousness, and carry a bee sting kit. One sold locally (they are available by prescription only) is the Anakit, which contains a syringe with two single doses of Epinephrine (adrenalin), four tablets of chio-amine antihistimine, two alcohol swabs and a tourniquet. The syringe is for intramuscular or subcutaneous injection, is intended for emergency use only and should never take the place of proper medical care at the hands of a professional. The kit retails for about $18 and is can be stored for two years.

The only defense you have against the hard stingers, the bees, is to avoid them.

About wood ticks: they carry Rocky Mountain spotted fever and Lyme disease. The former is more prevalent on the Eastern Seaboard than in the Rockies, and today kills about 5 percent of those who contract it, mostly because those people didn't know about the disease or how it is carried.

Last year there were 847 cases of Rocky Mountain spotted fever reported in the United States. This year 221 cases had been reported by the end of June, according to the federal Centers for Disease Control in Atlanta, compared with 315 by the same time last year.

Lyme disease, isolated by an NIH researcher in Lyme, Conn., several years ago, was reported in 1,498 persons last year, and in 599 in 1983. The disease, which produces arthritis-like symptoms, is so new that it is a reportable disease in only a few states, the CDC says. In 1984 there were 12 cases in Maryland, one in Virginia, and none in the District.

Insect repellent works well against ticks, and seasoned hikers and campers have tick inspection two or three times a day while in the woods, particularly in the District and surrounding states, where infestation can be high.

A tick must work at getting you infected, so just because you find one of the little eight-legged beasts dining on you doesn't mean you have a disease. What it means is you have a tick, and you might have a disease. So, using your fingernails or a tweezer, gently remove the tick, making sure you get his head too, and mash him, and then clean the spot where he was feeding on your blood with alcohol or, at least, soap and water.

Watch for such symptoms as fever, headache or rash, muscle ache and other flu-like symptoms. If they occur, consult a doctor. Don't worry about little things, because, in the words of the CDC's Dr. Joseph McDade, Rocky Mountain spotted fever "is a very frank illness," with very harsh and specific symptoms.

Both Rocky Mountain spotted fever and Lyme disease can be treated with antibiotics, McDade said, adding that in the bad old days the morbidity rate was 50 percent or higher.