As temperatures continue to rise, so will the incidence and transmission of infectious diseases (CDC, 2022a). This may happen through proximal causes, such as bacteria directly causing diarrhea, or distal causes, which are connected by a string of different events, eventually leading to disease. Proximal causes are easier to address, as you can directly identify the link between the cause and effect. However, to address distal causes, as there are many links, it can be more complex as changing one thing may impact the rest of the chain in an unknown way. Today, we will look at some diseases, transmission, and climate change.
Certain pests, such as mosquitoes and ticks, prefer warmer temperatures (CDC, 2022a). This allows them more time to reproduce, spread diseases, and migrate to other areas (CDC, 2022a). Vector-borne diseases are transmitted by living organisms known as vectors and have almost doubled and will continue to increase. Some types of diseases caused by mosquitoes include malaria and dengue, while ticks cause Lyme disease. If you wish to learn more about these diseases, click here!
Although this all sounds very severe, there are some easy ways you can protect yourself from mosquitoes and ticks:
- Use bug spray (Missouri Department of Health & Senior Services, n.d.).
- Wear long sleeves and long pants if possible when spending time outdoors (Missouri Department of Health & Senior Services, n.d.).
- Check standing water in your yard for mosquito breeding grounds or, better yet, get rid of them altogether (Missouri Department of Health & Senior Services, n.d.)!
- Check yourself for ticks (Missouri Department of Health & Senior Services, n.d.).
Diseases can also be spread through contact with animals. As animals are forced to move due to urbanization, pollution, and climate change, there is a greater chance for contact between humans and animals (CDC, 2022a). Zoonotic diseases can be transmitted through direct contact with fluids of an infected animal, such as blood, saliva, and urine. They can also be transmitted indirectly through contact with areas where the animals live, for example, if someone works on a farm. Of course, there is also the possibility of being transmitted through vectors or even through food such as milk, meat, and fruits contaminated by an infected animal. A well-known example of a zoonotic disease is Ebola, transmitted from fruit bats to humans through contact with a bat, a sick person, or a deceased person infected with the disease (CDC, (2023).
Here are a few things you can do to protect yourself from zoonotic diseases:
- Avoid contact with items that may have come into contact with infected people/animals (CDC, 2023).
- Avoid contact with fluids that may have come into contact with infected people/animals (CDC, 2023).
- Avoid contact with fluids or raw meat from animals such as bats that may be infected (CDC, 2023).
Did you know that fungi can also cause diseases? With temperature increases, fungi are now spreading to areas they could not survive in previously (CDC, 2022a). Valley fever is a disease caused by fungi spread through dust containing the fungus (CDPH, 2023). This disease affects the lungs and respiratory system of the infected person, causing symptoms like cough, chest pain, and fatigue (CDPH, 2023). There is also concern that there will be an increase in mould growth, following an increase in extreme weather events like flooding (CDC, 2022a). Certain moulds can even cause deadly brain and lung infections (CDC, 2022a). For example, aspergillosis is caused by Aspergillus mould, which affects the lungs when tiny bits of the mould are inhaled (NHS, 2021).
Here’s what you can do to protect yourself:
- Avoid areas with a lot of dust (CDC, 2022c).
- Wear a mask if exposed to dust (CDC, 2022c).
- Stay indoors during storms and keep windows and doors closed (CDC, 2022c).
- Clean skin to prevent skin infection if exposed to dirt and dust (CDC, 2022c).
Water as a distal cause
There are several ways that water might be a distal cause of disease. Changes in the flow of water and of water systems may be caused by heavier rainfall, which may also cause an increase in surface water turbidity, stirring up pathogens that are usually below the surface. With more rain, there may also be an increase in flooding events, which again might promote the growth of pathogens and stir more up to water surfaces. Furthermore, algal blooms are harmful to humans, animals and can make them sick and even cause death (CDC, 2022a). These algal blooms may spread more frequently into lakes, rivers, oceans, and bays, creating toxic blooms that look like foam or paint on the water’s surface (CDC, 2022a).
To prevent the growth of algal blooms, here’s what you can do:
- Avoid using too many fertilizers as the nutrients may end up in nearby bodies of water and encourage algae growth (CDC, 2022b).
- Stay out of water that looks like it has a layer of foam or paint on the surface (CDC, 2022b).
- Do not let your pets drink from water that looks infected (CDC, 2022b).
- If you or your pets get into the water, rinse immediately and do not let pets ingest the water (CDC, 2022b).
CDC. (2023). Ebola Disease. CDC. Retrieved Jun 28, 2023, from: https://www.cdc.gov/vhf/ebola/index.html
CDC. (2022a). Climate change and infectious diseases. CDC. Retrieved Jun 28, 2023, from: https://www.cdc.gov/ncezid/what-we-do/climate-change-and-infectious-diseases/index.html#:~:text=As%20the%20difference%20between%20environmental,to%20grow%20in%20people%27s%20homes.
CDC. (2022b). Protect Yourself and Your Pets. CDC. Retrieved Jun 28, 2023, from: https://www.cdc.gov/habs/prevention-control.html#:~:text=Top%20of%20Page-,Prevent%20harmful%20algal%20and%20cyanobacterial%20blooms%20from%20forming,grow%20more%20quickly%20than%20usual.
CDC. (2022c). Valley Fever (Coccidioidomycosis) Risk & Prevention. CDC. Retrieved Jun 28, 2023, from: https://www.cdc.gov/fungal/diseases/coccidioidomycosis/risk-prevention.html
CDPH. (2023). What is Valley fever? CDPH. Retrieved Jun 28, 2023, from: https://www.cdph.ca.gov/Programs/CID/DCDC/Pages/Coccidioidomycosis.aspx#:~:text=What%20is%20Valley%20fever%3F,contains%20the%20Valley%20fever%20fungus.
Missouri Department of Health & Senior Services. (n.d.). 2 Minute Drill for Vector-Borne Diseases. MO.gov. Retrieved Jun 28, 2023, from: https://health.mo.gov/living/healthcondiseases/communicable/2minutedrill/index.php
NHS. (2021). Aspergillosis. NHS. Retrieved Jun 28, 2023, from: https://www.nhs.uk/conditions/aspergillosis/#:~:text=Aspergillosis%20is%20a%20condition%20caused,lungs%20and%20cause%20breathing%20difficulties.