How to deal with the perils of summer

Dirty swimming pools. Disease-bearing bugs. Harmful rays of sun. Summer activities bring perils — but you can learn to avoid them.

Harmful germs may be lurking in your local public pool.
Harmful germs may be lurking in your local public pool. (istock)

Bad bug bites. Sunburn. Dirty pools. Heatstroke. The hazy, lazy days of summer, eagerly anticipated by New Englanders, can harbor a dark side, too. Illnesses from disease-bearing insects are on the rise. Public swimming pools may be teeming with bacteria, a recent study concluded. And long-awaited new labels for sunscreen products don’t tell consumers all they need to know to sufficiently protect themselves, say critics. Here’s a primer on common health concerns as the first official day of summer approaches.

Public pools

Harmful germs may be lurking in your local public pool. A survey of pool filters by researchers at the federal Centers for Disease Control and Prevention found that 58 percent had E. coli, a bacteria normally found in the gut and in feces.


The researchers said their findings likely indicates that swimmers did not shower thoroughly before diving in, or that children might have had an episode of diarrhea while swimming.

The type of E. coli found was not the serious strain that can cause significant illness, however it may cause mild stomach distress. Other germs were also discovered in the tests, including Pseudomonas aeruginosa, which was present in 59 percent of the samples. The bacteria can cause skin rashes and ear infections.

“It’s us swimmers who are bringing the germs into the water,” said study co-author Michele Hlavsa, chief of CDC’s Health Swimming Program.

Hlavsa’s team tested 161 public pools in Atlanta last summer, but said similar contamination is probably widespread because swimmer hygiene is unlikely to significantly differ around the country.

Chlorine and other pool disinfectants kill germs, but they do not work instantly, Hlavsa said, and they often aren’t used in sufficient levels. Swimmers typically blame high chlorine levels for their red, burning eyes, but Hlavsa said chlorine isn’t the culprit — it’s the contaminants that seep into the pool from swimmers who don’t adequately shower before jumping in.


“It’s chlorine mixed with sweat, and urine, and personal care products, anything that contains nitrogen, like your hair conditioner for example, that makes the eye irritant,” known as chloramines, Hlavsa said.

Nitrogen, from personal care products such as moisturizers, also saps the effectiveness of the chlorine, she said.

Smart swimming

Tips to prevent and avoid dirty water:

Don’t swim when you have diarrhea.

Shower with soap before you start swimming.

Rinse before you get back into the water.

Don’t swallow the water you swim in.

Wash your hands after using the toilet or changing diapers.

Take children on bathroom breaks every 60 minutes or check diapers every 30–60 minutes.

Change diapers in the bathroom or diaper-changing area and not poolside where germs can get into the water.

Test the cleanliness before diving in: Most superstores, hardware stores, and pool-supply stores sell pool test strips.

SOURCE: Centers for Disease Control and Prevention


Simply put, heat stroke is when your body’s ability to tolerate the heat is surpassed.

The elderly are typically most at risk because aging bodies aren’t as able to efficiently produce sweat to cool off, and certain medications taken for chronic conditions, including heart medicines, make it harder for the body to regulate temperature, said Dr. Andrew Ulrich, executive vice chair of emergency medicine at Boston Medical Center.

But plenty of others, including those exercising in extreme heat, and the homeless run into problems, too, Ulrich said.


“The warning sign we look for is a change in mental status,” Ulrich said. “People are confused and disoriented.”

In serious cases, when a person’s body temperature rises above 103 degrees, heart and brain damage can occur.

“When the brain is warmer than it likes . . . people can have seizures,” he said.

Early signs of heatstroke include feeling thirsty, hot, woozy, dizzy, and nauseous.

Staying well-hydrated helps prevent heatstroke, but drinking alcohol in the heat can dehydrate you, Ulrich said.

“Although you think you are hydrating, you lose fluid because it makes you pee a lot,” he said. “It [also] alters our common sense skills and we ignore the warning signs.”

Heat exhaustion and stroke

Heat exhaustion symptoms:

Heavy sweating

Cold, pale, clammy skin

Fast, weak pulse


Nausea or vomiting

Heat stroke symptoms:

Hot, red, or dry skin

Rapid and strong pulse

Possible unconsciousness

Body temperature above 103 degrees

What to do:

Move to a cooler location and lie down.

Apply cool, wet cloths to as much of your body as possible.

Sip water and get medical attention if vomiting.

CALL 911: This is a medical emergency. Move to a cooler environment. Reduce the person’s body temperature with cool cloths or a bath. Do NOT give fluids.


Sunscreen labels

This will be the first summer that new federal rules require more information on sunscreen labels. Products that claim a “broad spectrum” of protection must include protection against two types of harmful ultraviolet sunlight, UVA and UVB.


Manufacturers must include a Sun Protection Factor (known as SPF) of at least 15 in their products to claim broad spectrum protection under the new US Food and Drug Administration requirements.

But products that boast high SPF levels — claims critics contend are misleading and dangerous — will still be allowed. The FDA says it has no evidence that sunscreens with an SPF above 50 provide any greater protection than those with a lower SPF, but declined to ban the higher ratings, saying more study is needed.

Consumers are more likely to misuse a high-SPF product — not reapplying them often enough or staying in the sun too long — mistakenly believing they can safely handle more ultraviolet exposure than with a lower one said Sonya Lunder, senior research analyst at the Environmental Working Group, a Washington-based health research and advocacy organization.

Lunder said sunscreens sold in Europe offer superior protection against UVA rays because companies are allowed to use chemicals not approved for sale in the US. She said the FDA, which has been reviewing the chemicals for use in the US since 2005, is dragging its heels.

FDA spokeswoman Andrea Fischer said in a statement that the agency is “working diligently” to review the safety and effectiveness of the chemicals, but offered no timetable for when it may decide.

The agency’s new rules for sunscreen labeling prohibit manufacturers from claiming sunscreens are waterproof or sweatproof — claims not backed by science.


The ABCs of SPF

Sunburn Protection Factor can be tricky, despite new federal regulations aimed at demystifying the amount of protection sunscreens truly provide. We try to shed some (safe) light:

No sunscreen completely blocks the sun’s harmful rays.

Limit your sun exposure, especially between 10 a.m. and 2 p.m. when rays are strongest.

Apply sunscreen at least 15 minutes before sun exposure.

Reapply sunscreen at least every two hours; more often if swimming or sweating.

Use a sunscreen that is labeled “broad spectrum,” which offers some protection against UVA and UVB rays, which both contribute to skin cancer.

SOURCE: US Food and Drug Administration

Bad bugs

Massachusetts disease trackers are uneasy. Bugs — mosquitoes and deer ticks, in particular — proliferated last summer, spreading misery across the state.

More residents were infected last year with West Nile Virus, a mosquito-borne illness, than ever recorded in one season in Massachusetts. Confirmed cases of Lyme disease and babesiosis, both diseases spread by ticks, jumped sharply.

Babesiosis, not as well-known as Lyme disease, typically produces mild symptoms, such as fever, chills, headache, achy joints and muscles, fatigue and nausea, and can be treated with medications.

Health officials who track mosquitoes said that the number of mosquito samples that tested positive for Eastern equine encephalitis soared last year. Seven residents were infected, the most in a single season in Massachusetts in decades. Three died.

“Our concern is that we may see this every year now,” said Dr. Alfred DeMaria, the state health department’s top disease tracker.

Massachusetts used to see a spike in Eastern equine infections about once every 13 years, and the cases were typically confined to the Southeastern section of the state, with its large marshes — prime breeding grounds for the types of mosquitoes that spread the disease.

Last season, five of the seven infections were outside that region, striking in North, Central and Western Massachusetts.

Health officials say the best protection against mosquitoes is to use insect repellant, cover up exposed skin, and avoid outdoor activities from dusk to dawn, when mosquitoes are most active.

To protect against ticks, which live in brushy, wooded or grassy places, health officials recommend when out hiking in these areas to use a repellent with the chemical DEET or permethrin, walking on cleared trails, and wearing a long-sleeved shirt, and long, light-colored pants tucked into your socks or boots.

Disease-bearing bugs

Disease-bearing bugs wreaked misery last summer. A snapshot from the Mass. Department of Public Health:

233 confirmed cases of babesiosis, spread by the bite of an infected deer tick, a 22% increase from 2011.

3,386 confirmed Lyme disease cases, spread by infected deer ticks, a 27 percent increase from 2011.

33 people infected with mosquito-borne West Nile virus, the most recorded in Massachusetts in a season.

7 people infected with Eastern equine encephalitis, also spread by mosquitoes.

Kay Lazar can be reached at Follow her on Twitter @GlobeKayLazar.