HLS Environmental Challenges and Sustainable Solutions

Human Impact and Ecological Consequences

  • Chimpanzees and Resource Depletion

    • Chimpanzees in the Congo and Africa previously ate a specific type of palm for essential elements like lithium, which is required for metabolism in both chimpanzees and humans.

    • Due to human harvesting of this palm for weaving, it is no longer available to chimpanzees.

    • Consequently, chimpanzees are now consuming bat guano (feces) to obtain the necessary nutrients.

    • Risk of Virus Transmission: Bat guano, unfortunately, carries various pathogens, including dozens of coronaviruses that bats host without getting sick (due to millions of years of co-evolution).

    • This shift in diet potentially exposes chimpanzees to more coronaviruses and other viruses.

    • Cross-Species Transmission Risk: There is a potential for another COVID-19-like outbreak from cross-species transmission, especially given that chimpanzees share 98%98\% to 99%99\% of our genes, making virus transmission to humans easier.

  • Deforestation, Urbanization, and Disease Spread

    • Human encroachment into wild places through deforestation and urbanization contributes to disease emergence.

    • Near forests and native farmlands, there's an increase in malaria, directly linked to environmental demarcation, which affects mosquito populations.

  • Emerging Viruses and Pathogens

    • Definition: Emerging viruses are relatively new ones or pathogens (including bacteria) that have only appeared on the radar in recent decades.

    • This doesn't mean they literally emerged last year but are newly discovered or identified as significant threats.

    • Examples: HIV was an emerging pathogen in the 19701970s and 19801980s, though it existed since the mid-19201920s. COVID-19 is a recent example.

Disease Threats: Mosquito-borne & Water-borne

  • Mosquito-borne Diseases

    • Spread Due to Climate Change: Mosquito populations capable of carrying tropical diseases are expanding their range in both directions due to overall increasing heat.

    • Resurgence in the United States: Recent cases of native St. Louis Encephalitis (George Hengen disease) have emerged in the US.

    • West Nile virus, which had not existed in the US decades ago, was almost certainly transported from the Middle East and established a foothold in bird populations.

    • Historical Outbreaks: In 17931793, Philadelphia (then the US capital) experienced a severe Yellow Fever outbreak, a mosquito-borne disease.

      • It killed an estimated 10%10\% to 20%20\% of the city's population.

      • This highlights that mosquito-borne diseases can occur even in typically temperate zones, often brought by ships from tropical regions (e.g., Caribbean).

    • Control Measures: Mosquito-borne diseases have been controlled by draining swamps and active public health mosquito control, but they remain a threat even in wealthy, temperate countries.

    • Mosquito Seasons: The eastern US generally experiences longer mosquito seasons.

    • Impact of Extreme Heat/Dryness: In some hotter, drier areas, mosquito seasons might paradoxically shorten because it's too arid for mosquitoes to reproduce (they need shady standing water for egg-laying).

    • Dengue Fever: Native dengue fever cases have emerged in Los Angeles, indicating local transmission by mosquitoes, not just imported cases.

      • Dengue has exploded globally in range and severity.

      • It's an interesting disease with 33 types.

      • Initial infection with one type is usually not severe, but a second infection with a different type can cause severe illness due to a stronger immune response that paradoxically worsens the disease.

  • Water-borne Diseases

    • Cholera: Historically one of the biggest waterborne diseases, causing severe dehydration (flushing fluid from both ends).

      • Can lead to death in about 2424 hours from dehydration and organ failure.

      • Different strains exist, some causing mild disease, others severe.

      • Resurgence Factors: Changing conditions, especially flooding and warmer temperatures, are making waterborne diseases more frequent.

        • Flooding contaminates freshwater sources and flushes sewage into water systems.

        • Warmer temperatures favor certain pathogens.

    • Examples: Besides cholera (which loves warmer temperatures), others include Leptospirosis, Campylobacter, and Cryptosporidium. E. Coli, common in sewage, can also cause outbreaks, especially for immune-compromised individuals, though usually not a problem internally.

    • Haiti Cholera Epidemic (20102010): Following a major earthquake in Port-au-Prince, Haiti (20102010), UN peacekeepers (from an unnamed country) inadvertently introduced cholera by situating a latrine too close to a water source.

      • This led to a cholera epidemic that killed tens of thousands, amplifying the disaster for a vulnerable population with poor water access.

    • Algae Blooms: Toxic algae blooms are occurring more frequently due to warming and excess nutrients.

      • They block sunlight and deplete oxygen, creating