14.2 Climate Change and Emerging Parasitic Diseases

Climate change is shaking up the world of parasites. Rising temperatures and weird weather are helping parasites and their carriers spread to new places. This means more people and animals could get sick from parasitic diseases.

Scientists are racing to understand how climate change affects parasites. They're developing new ways to track and fight these diseases. It's crucial to prepare for the changing landscape of parasitic threats in our warming world.

Climate Change and Parasitic Diseases

Relationship between Climate Change and Parasitic Disease Emergence

Top images from around the web for Relationship between Climate Change and Parasitic Disease Emergence

• 

  Frontiers | Emerging Zoonotic Diseases: Should We Rethink the Animal–Human Interface? View original

  Is this image relevant?

• 

  Frontiers | Outbreaks of Vector-Borne and Zoonotic Diseases Are Associated With Changes in ... View original

  Is this image relevant?

• 

  Climate change and infectious diseases 2019 - Canada.ca View original

  Is this image relevant?

• 

  Frontiers | Emerging Zoonotic Diseases: Should We Rethink the Animal–Human Interface? View original

  Is this image relevant?

• 

  Frontiers | Outbreaks of Vector-Borne and Zoonotic Diseases Are Associated With Changes in ... View original

  Is this image relevant?

1 of 3

Top images from around the web for Relationship between Climate Change and Parasitic Disease Emergence

• 

  Frontiers | Emerging Zoonotic Diseases: Should We Rethink the Animal–Human Interface? View original

  Is this image relevant?

• 

  Frontiers | Outbreaks of Vector-Borne and Zoonotic Diseases Are Associated With Changes in ... View original

  Is this image relevant?

• 

  Climate change and infectious diseases 2019 - Canada.ca View original

  Is this image relevant?

• 

  Frontiers | Emerging Zoonotic Diseases: Should We Rethink the Animal–Human Interface? View original

  Is this image relevant?

• 

  Frontiers | Outbreaks of Vector-Borne and Zoonotic Diseases Are Associated With Changes in ... View original

  Is this image relevant?

1 of 3

• Climate change, including rising temperatures, altered precipitation patterns, and extreme weather events, can significantly influence the emergence and spread of parasitic diseases
• Changes in temperature and humidity affect the survival, development, and reproduction of parasites and their vectors, potentially expanding their geographic range and increasing their abundance
• Climate change alters the distribution and behavior of host species (wildlife, livestock), creating new opportunities for parasites to infect new hosts and establish in new areas
• Shifts in vegetation and land use patterns driven by climate change create new habitats suitable for parasites and their vectors, facilitating their spread and establishment in previously unaffected regions
• Climate change disrupts the delicate balance of ecosystems, leading to changes in predator-prey relationships and host-parasite dynamics
  • May contribute to the emergence of new parasitic diseases or the resurgence of previously controlled ones
  • Example: Increased rodent populations due to milder winters can lead to a higher prevalence of rodent-borne parasites

Impact of Climate Change on Parasitic Disease Distribution and Prevalence

• Climate change expands the geographic range of parasites and their vectors, allowing them to establish in areas where they were previously absent or rare
  • Exposes new populations to infection
  • Example: The spread of the tick-borne parasite Babesia to northern latitudes as temperatures warm
• Warmer temperatures and altered precipitation patterns lengthen the transmission seasons of parasitic diseases, increasing the risk of infection for humans and animals
• Climate change affects the abundance and distribution of host species (wildlife reservoirs, livestock), influencing the prevalence and transmission dynamics of parasitic diseases
• Changes in human behavior and land use patterns in response to climate change (increased outdoor activities, agricultural practices) increase exposure to parasites and their vectors
• The impact of climate change on parasitic diseases varies depending on the specific parasite, its transmission mode, and the local environmental conditions, requiring targeted assessments and adaptation strategies

Factors in Parasitic Disease Spread

Temperature and Precipitation

• Temperature plays a crucial role in the development and survival of parasites and their vectors, with warmer temperatures often accelerating their life cycles and increasing their reproductive rates
  • Example: Higher temperatures can shorten the development time of mosquito larvae, leading to larger mosquito populations and increased transmission of mosquito-borne parasites like malaria
• Changes in precipitation patterns (increased rainfall, prolonged droughts) affect the availability of water sources and moisture levels, which are essential for the survival and development of many parasites and their vectors
  • Example: Increased rainfall can create more breeding sites for mosquitoes, leading to higher populations and increased transmission of parasitic diseases like lymphatic filariasis

Human Migration and Globalization

• Human migration and displacement driven by climate change (in response to extreme weather events or resource scarcity) introduce parasites to new areas and expose susceptible populations to infection
  • Example: Displaced populations living in overcrowded conditions with limited access to sanitation are at higher risk of parasitic infections like schistosomiasis
• Globalization and international trade, which may be influenced by climate change, contribute to the spread of parasites and their vectors through the movement of goods, animals, and people across borders
  • Example: The global trade of ornamental plants can inadvertently introduce snail intermediate hosts of schistosomiasis to new regions

Environmental Changes

• Rising sea levels and coastal flooding due to climate change create new breeding sites for vectors (mosquitoes) and facilitate the spread of water-borne parasitic diseases
  • Example: Saltwater intrusion in coastal areas can create brackish water habitats suitable for the snail hosts of schistosomiasis
• Shifts in vegetation and land use patterns driven by climate change create new habitats suitable for parasites and their vectors, facilitating their spread and establishment
  • Example: Deforestation can lead to increased contact between humans and non-human primates, facilitating the zoonotic transmission of parasites like Plasmodium knowlesi malaria

Climate Change Impact on Parasitic Diseases

Expansion of Geographic Range

• Climate change expands the geographic range of parasites and their vectors, allowing them to establish in areas where they were previously absent or rare, potentially exposing new populations to infection
  • Example: The northward expansion of the kissing bug (Triatoma spp.), the vector of Chagas disease, in North America as temperatures warm
• Shifts in the distribution of host species (wildlife reservoirs, livestock) due to climate change can introduce parasites to new areas and facilitate their establishment
  • Example: The altitudinal shift of the mountain pine beetle and its associated parasitic nematode, Bursaphelenchus xylophilus, to higher elevations as temperatures increase

Increased Transmission and Prevalence

• Warmer temperatures and altered precipitation patterns can lengthen the transmission seasons of parasitic diseases, increasing the risk of infection for humans and animals
  • Example: Longer periods of warm weather can extend the active season of ticks, increasing the risk of tick-borne parasitic diseases like babesiosis and anaplasmosis
• Changes in temperature and humidity can affect the survival, development, and reproduction of parasites and their vectors, potentially increasing their abundance and the prevalence of parasitic diseases
  • Example: Increased survival and reproduction of the snail intermediate hosts of schistosomiasis in warmer water temperatures can lead to higher transmission rates

Altered Host-Parasite Dynamics

• Climate change can affect the abundance and distribution of host species (wildlife reservoirs, livestock), influencing the prevalence and transmission dynamics of parasitic diseases
  • Example: Drought conditions can concentrate wildlife around limited water sources, increasing the transmission of water-borne parasites like Cryptosporidium
• Changes in predator-prey relationships and host-parasite dynamics due to climate change can contribute to the emergence of new parasitic diseases or the resurgence of previously controlled ones
  • Example: Declines in predator populations due to climate change can lead to increased rodent populations, amplifying the transmission of rodent-borne parasites like Echinococcus multilocularis

Mitigating Climate Change Effects on Disease Transmission

Surveillance and Early Warning Systems

• Strengthen surveillance systems and monitoring programs to detect and respond to changes in the distribution and prevalence of parasitic diseases in the context of climate change
  • Example: Implement sentinel surveillance sites in areas at high risk of climate-related parasitic disease emergence to detect early signs of outbreaks
• Develop and implement early warning systems that integrate climate data, disease surveillance, and risk assessment to anticipate and prepare for potential outbreaks
  • Example: Use climate models and remote sensing data to predict areas at increased risk of malaria outbreaks based on temperature and rainfall patterns

Research and Innovation

• Invest in research to better understand the complex interactions between climate change, ecosystems, and parasitic diseases, and to develop innovative control and prevention strategies
  • Example: Study the impact of climate change on the genetic diversity and virulence of parasites to inform the development of targeted interventions
• Develop new diagnostic tools, treatments, and vaccines that are effective against parasitic diseases in the context of climate change
  • Example: Invest in the development of a vaccine against schistosomiasis that is effective in regions where climate change is altering the distribution and abundance of snail intermediate hosts

Vector Control and Disease Prevention

• Enhance vector control programs (insecticide-treated bed nets, indoor residual spraying, larval source management) to reduce the populations of disease-carrying vectors in a changing climate
  • Example: Implement community-based mosquito control programs that target breeding sites and promote the use of insecticide-treated bed nets in areas at increased risk of malaria due to climate change
• Promote public awareness and education campaigns to inform communities about the risks of parasitic diseases in a changing climate and the preventive measures they can take
  • Example: Develop targeted health education materials that explain the links between climate change and parasitic diseases and provide guidance on personal protection measures like proper clothing and repellent use

Health System Resilience

• Strengthen health systems and increase their resilience to climate change impacts, ensuring adequate resources, infrastructure, and trained personnel to diagnose, treat, and manage parasitic diseases effectively
  • Example: Train healthcare workers in the diagnosis and treatment of emerging parasitic diseases and equip health facilities with the necessary supplies and equipment to handle potential outbreaks
• Improve access to clean water, sanitation, and hygiene facilities to reduce the transmission of water-borne parasitic diseases, particularly in areas affected by climate change-related water scarcity or flooding
  • Example: Implement community-based water treatment and safe storage programs in areas at increased risk of water-borne parasitic diseases due to climate change-induced flooding or drought