Global health 3 (MDGs and SDGs)

Communicable Disease

 “.... also known as infectious disease or transmissible diseases, are illnesses that result from the infection, presence and growth of pathogenic (capable of causing disease) biological agents in an individual human or other animal host”

Noncommunicable diseases (NCDs)

Diseases that are not spread through an infectious agent

Acute Disease

 a disease that develops rapidly, lasts for a short time, and has clear symptoms, may be caused by infectious agents (flu, pneumonia), but may also have non-infectious causes (appendicitis, acute myocardial infarction) 

Microbe

• microscopic organism 

• benefits: synthesize vitamins, prevent pathogenic organisms from invading, aids digestions, improve immune functions)

• Types: viruses, bacteria, protozoa, helminths (worms)

Viruses

• Packaged DNA or RNA 

• Protein (and sometimes also lipid) coat 

• Attack and invade host cells 

• Does not propagate without a host 

• Ex: cold, HIV, measles, polio, dengue, yellow fever, zika, Ebola, Covid-19

Bacteria

• Single-celled organisms visible with a microscope

• One ring of DNA, sometimes PLASMIDS 

• Acquire genetic material from other organisms 

• Ex: strep throat, tuberculosis, leprosy

Protozoa

• Single celled organism 

• Free-living or parasitic

• Those of interest to human health are generally able to multiply in a human host

• Typically transmitted via the fecal-oral (contaminated food or objects that have been in contact with feces) route 

Helminths

• Multicellular organisms 

• Often macroscopic 

• Either free-living or parasitic

• 3 main groups 

  • Flatworms: flukes and tapeworms

  • Thorny-headed worms

  • Roundworms

Parasite

organism that benefits from a host and that harms the host in some way

Pathogen

 any agent that can cause disease

Zoonosis

a disease of vertebrate animals that is transferred to humans (breed)

Vector

typically, an organism that transmits a pathogen (ex: mosquitos, fleas, flies)

Definitive Host

the host in which a parasite sexually reproduces/completes its lifecycle

Intermediate Host

the host in which a parasite develops but does not sexually reproduce (may asexually reproduce)

ex: For the malaria parasite, the intermediate host is HUMANS

Reservoir

“...any animal,person, plant, soil, substance – or combination of any of these – in which the infectious agent normally lives.” (CDC)

• Infectious agent must depend mainly on the reservoir for its existence 

• Infectious agent must be able to multiply in the reservoir 

Dracunculiasis (Guinea Worm Disease)

 (one of the neglected tropical disease or NTD)

• Caused by the nematode Dracunculus medinensis

• Infection caused by drinking water contaminated with copepods (tiny crustaceans) that carry D. medinesis larvae

Dracunculiasis Cycle

1. Human drinks unfiltered water containing copepods (like plankton from spongebob) with the L3 larvae 

2. Larvae is released when copepods die and Larvae penetrates the hosts stomach and intestinal wall, They mature and reproduce

3. Fertilized female worm migrates to surface of skin (anywhere on the body, usually lower legs though), causes a blister and discharges larvae

4. Female worm begins to emerge from skin one year after infection → Larva is released into water (ppl tend to put blister in the water) from the emerging female worm

5. Larvae is consumed by a copepod

6. Larvae undergoes two molts and becomes a L3 larvae

Dracunculiasis Pathology

1. Pain from emergence of adult worms 

2. Secondary bacterial infection 

3. Trapped adult worms

Dracunculiasis Diagnosis

1. Characteristic blister 

2. Adult worm emerging from skiing

Dracunculiasis Treatment

1. Remove adult worm (about 5cm/day) 

   1. 1674, worm removal wrapping the adult around a stick 

   2. Removal surgery is sometimes possible if it is located in a place that makes it possible 

2. Control secondary bacterial infection

Infection Risk Factors

1. Little to no access to safe drinking water 

2. Living in a community where other people have dracunculiasis ‘

3. Lack of access to healthcare facilities 

4. Lack of opportunity to filter unsafe water 

5. Lack of access to chemicals to kill copepods

6. Living in a place where there is insufficient political will or ability to address dracunculiasis

Eradication Efforts

• Dracunculiasis eradication to begin in 1980 

• The World Health Assembly (WHA) called for full eradication effort in 1986

  • Eradication: the absence of dracunculiasis for 3 consecutive years in all countries 

• Currently: concerns about dogs and other animals serving as reservoirs

15

About how many cases of dracunculiasis were recorded for the calendar year 2024

The Millennium Development Goals (MDGs)

were in place from around 2000 to 2015, prior to the implementation of the SDGs.

• were a set of eight goals with time-bound targets to improve the health and development of impoverished nations by 2015

1) hunger

2) education

3) gender equality

4) child health

5) women’s health

6) infectious disease

7) environmental stability

The Sustainable Development Goals (SDGs)

a set of 17 goals that focus on diverse aspects of development. They are geared toward decreasing human suffering and reversing the dangerous trajectory of climate change by 2030.

1. End poverty in all its forms everywhere.

2. End hunger, achieve food security and improved nutrition, and promote sustainable agriculture.

3. Ensure healthy lives and promote well-being for all at all ages.

4. Ensure inclusive and equitable quality education and promote lifelong learning opportunities for all.

5. Achieve gender equality and empower all women and girls.

6. Ensure availability and sustainable management of water and sanitation for all.

7. Ensure access to affordable, reliable, sustainable modern energy for all.

8. Promote sustained, inclusive, and sustainable economic growth, full and productive employment, and decent work for all.

9. Build resilient infrastructure, promote inclusive and sustainable industrialization, and foster innovation.

10. Reduce inequality within and among countries.

11. Make cities and human settlements inclusive, safe, resilient, and sustainable.

12. Ensure sustainable consumption and production patterns.

13. Take urgent action to combat climate change and its impacts.

14. Conserve and sustainably use the oceans, seas, and marine resources for sustainable development.

15. Protect, restore, and promote sustainable use of terrestrial ecosystems, sustainably manage forests, combat desertification, halt and reverse land degradation, and halt biodiversity loss.

16. Promote peaceful and inclusive societies for sustainable development, provide access to justice for all, and build effective, accountable, and inclusive institutions at all levels.

17. Strengthen the means of implementation and revitalize the Global Partnership for Sustainable Development.

Vertical Programs

programs that targeted specific conditions or diseases. Often times these vertical programs alone were not really effective in making a larger scale improvement on health. 

Diagonal program

Leverages the money for a vertical program and uses it for other health improvements and systems strengthening.