## Infectious diseases Due to global warming, mosquitoes, ticks, and other carriers of infectious diseases are reproducing faster and expanding into new territories. Frequent droughts and floods (such as those caused by rapid snow melt) contribute to the spread of waterborne [infections](https://ul.orna.me/KOge/librarydisease?id=7) like cholera. Algae blooms in bodies of water release toxins that can cause poisoning. ## Respiratory illnesses Rising temperatures contribute to methane emissions and ozone formation—the main component of smog. These factors lead to an increase in respiratory illnesses such as chronic obstructive [pulmonary](https://ul.orna.me/KOge/librarydisease?id=2) disease (COPD), bronchial asthma, bronchitis, and pneumonia. In addition, droughts increasingly lead to wildfires, which pollute the air and trigger respiratory conditions. ## Allergies Climate change causes=== more frequent and intense rainfall, fewer frost days, and a rise in atmospheric carbon dioxide. The more CO₂ in the air, the more pollen plants produce—making life harder for [allergy](https://ul.orna.me/KOge/librarydisease?id=21) sufferers. Warmer temperatures also encourage the growth of mold and fungi indoors, which can trigger allergic reactions. ## Cardiovascular diseases People with cardiovascular conditions are more sensitive to heat. For them, climate warming increases the risk of heart attacks, strokes, angina attacks, and other heart-related problems. > On average, for every 1 °C increase in body temperature, the heart rate rises by about 10 beats per minute. ## Mental health Stressful situations triggered by climate change—such as natural disasters and forced migration—negatively affect mental health. People who experience natural catastrophes often suffer from post-traumatic [stress](https://ul.orna.me/KOge/librarydisease?id=19) disorder (PTSD) and depression. Hot weather also poses a risk to individuals with severe mental illnesses such as schizophrenia, since medications may impair thermoregulation or cause hyperthermia. Dementia is also a risk factor during extreme heat. > Since the early 20th century, the planet's average annual temperature has risen by about 1.5 °C.