Human health can be affected by a large number of weather events associated with climate change. Climate change in Bulgaria manifests itself through an increase in average annual air and water temperatures, an increase in heat and cold waves, a change in annual precipitation patterns, an increase in intense precipitation events, an increase in extreme weather events (winds, cyclones, floods and droughts) and changes in the intensity of ultraviolet radiation. All these changes affect health.

Health effects can be differentiated as primary and secondary:
- Primary effects directly affect human health, for example through heat and cold waves, ultraviolet radiation and flooding

- Secondary effects affect human health indirectly through other climate-influenced factors such as pollen, vector-borne diseases, fires, contaminated food, water and air, and damaged crops

The primary and secondary health effects of climate change can be differentiated into the following groups:
- Heat-related morbidity and mortality
- Morbidity and mortality associated with extreme weather conditions
- Cardiovascular diseases including strokes, asthma, respiratory allergies and respiratory diseases
- Diseases caused by food and nutritional factors
- Water-related diseases
- Mental health and stress-related disorders, neurological diseases and disorders

The key future vulnerabilities for Bulgaria are:

- Effects of temperature and humidity on health. These include the expected increase in: The number of deaths from cardiovascular disease and strokes in large cities in summer due to heat waves and the urban heat island effect; vector-borne diseases; campylobacter infections; respiratory diseases due to the greater influence of CO2, dust and PMF in warmer air; and allergic diseases due to earlier blooms and increased concentrations of pollen, spores and other allergens in the air

- Emergency health effects associated with weather conditions. These include the expected increase in: mortality due to extreme weather events and fires, with this increase greater in vulnerable groups; water and foodborne morbidity due to damaged infrastructure; and post-traumatic stress disorder (PTSD).

- Change in health effects associated with precipitation. It includes the expected increase in enterocolitis, an infectious inflammatory disease of the small intestine or colon, due to a combination of more frequent rainfall and higher annual average temperatures allowing the development of its causative microorganisms. Also, enteritis caused by non-cholera vibrio due to more abundant rainfall and higher humidity levels as well as the higher water temperature in the Black Sea

It is important to note that climate-related health impacts disproportionately affect more vulnerable populations, in particular children and the elderly, people with chronic diseases, people of low socio-economic status, those living in poverty and those with harmful habits (alcohol, drug and tobacco use).