Rwanda is a blessed country with lush greenery and a moderate climate. But still, during the dry season, the sun becomes very strong. Sun is very useful for the human body. But, in excess it is harmful. A sunburn is a form of radiation injury that occurs due to overexposure to hot sun, affecting the skin and eyes. Mild exposure to the sun results in tanning. However, excess exposure results in red skin, which feels hot to the touch. Blisters may form in severe cases, with or without peeling of the skin. Some persons experience fever. There may be associated pain, fatigue, and dizziness. The effects of exposure to the sun may be visible, two to six hours after the exposure. In case of very strong sun, it may be visible in 30 minutes. Apart from exposure to the sun, sunburn can also occur due to exposure to artificial sources of ultraviolet light like welding arcs, tanning lamps, or ultraviolet germicidal irradiation. Several factors influence the occurrence and severity of sunburn. Light-skinned people are more vulnerable because their skins have less melanin (pigment imparting colour to the skin and protecting against sunburn). Little children and elderly people are more likely to develop sunburn after exposure to strong sunlight as the protective mechanisms of their body are not so strong. It also depends on the climate and time of the day. The risk is higher in the dry season as there is more sunlight. Sunburn can occur with cloudy weather too, though the risk is less because the ultraviolet light of the sun passes through clouds as well. The time of the day when one moves out or works outside also influences the occurrence of sunburn and its severity. Usually, there is strong sun from 10 in the morning to late afternoon. Someone out at that time carries the risk of developing sunburn. Clothing worn can also protect against strong sunlight or expose one to it. Proximity to the equator, proximity to reflecting surfaces such as water, sand, and snow, and high altitude are other factors. In recent decades, the incidence and severity of sunburn has increased all over the world due to chemical damage to the atmosphere’s ozone layer. Certain medicines like some antibiotics, antiacne drugs, oral contraceptives, and tranquilizers make the skin more sensitive to ultraviolet radiation, thus causing sunburn easily. Persistent severe exposure to sunlight is a risk factor for malignant melanoma (cancer of the skin) and other skin cancers. As such it subsides within minutes to hours after the exposure stops. But if exposure is repetitive, it can be troublesome. Prevention lies in avoiding direct exposure to strong sunlight. People wear short dresses in hot climates to feel cool, but it also exposes them to the risk of sunburn, particularly if they remain in direct sunlight for a long time, without any shade. Full dresses are better in this regard. As the eyes are also affected, wearing suitable sunglasses also offers protection against sunburn. This also prevents premature wrinkling. Using hats, and cotton gloves, are other protective measures. Use of a sunscreen lotion, 15-20 minutes before moving out in the sun, and a second application, 15-30 minutes after exposure, helps in protecting the skin from sunburn. Mild tanning of the skin protects against sunburn by augmenting the amount of melanin in the skin. As the DNA of skin cells is damaged in sunburn, a diet rich in anti-oxidants is very beneficial in reducing the risk. Supplements of vitamins C and E are also useful in this regard. Water should be consumed in good quantity. No active immediate treatment is needed for a sunburn. Cool compresses can be applied over the affected area. In case of severe pain and redness, anti-inflammatory drugs can help. Dr Rachna Pande is a specialist in internal medicine.
