Your Body Almanac

Hawaii

Tropical sun, volcanic smog on the Big Island and leptospirosis in streams.

Hawaii's sun is among the most intense anywhere in the US. On Hawaii Island, volcanic gas can drift over communities as vog. And Hawaii reports more leptospirosis than any state, from bacteria in fresh water and wet soil.

01

Tropical UV

Near the tropics the midday sun is almost straight overhead, so UV is strong all year. The UV Index can reach 15 or 16 in the tropics at high elevation, such as Haleakala and Mauna Kea. Water and sand reflect still more onto your skin.

SourcesUV Index — What Is It? (NOAA Climate Prediction Center)Sun Safety (CDC)
Wear sunscreen every dayDailyPut broad-spectrum SPF 30+ on exposed skin each morning and reapply every two hours outdoors. Wear sun-protective clothingAs neededCover up with a wide-brimmed hat, UV-blocking sunglasses and tightly woven long sleeves when you are out in the sun. Check your skin for changesAs neededLook over your whole body on a regular schedule for new spots or moles that change, itch or bleed.
02

Vog from Kilauea

When Kilauea is active, sulfur dioxide and fine particles form volcanic smog, or vog. It can irritate eyes, nose and throat and trigger asthma; people with asthma, heart or lung disease, children, older adults and outdoor exercisers are most affected. Ordinary masks, even N95s, do not filter out the sulfur dioxide gas, so staying indoors and easing off outdoor exertion on bad days is the main defense.

SourcesFrequently Asked Questions About Volcanic Smog (USGS Hawaiian Volcano Observatory)DOH Urges Caution With Elevated Volcanic Gas Emissions (Hawaii Department of Health)
Check the air qualityAs neededLook up your local Air Quality Index before outdoor work or exercise, and scale back when it is high.
03

Leptospirosis in fresh water

Leptospirosis bacteria from rats, mongooses and other animals live in Hawaii's streams, ponds and wet soil. Within the US, Hawaii reports the most cases after Puerto Rico. The bacteria get in through cuts and through the eyes, nose and mouth, so hiking through streams, swimming in ponds and farm or yard work in mud are the main exposures.

SourcesLeptospirosis (Hawaii Department of Health)
Keep cuts out of fresh water and mudAs neededWhere leptospirosis is common, stay out of streams, ponds and floodwater with open cuts, and keep your head above fresh water.

When to see a professional

See a doctor for fever, headache, muscle aches or red eyes in the weeks after stream, pond or mud exposure, and mention it. Get care for wheezing or chest tightness on vog days.