HP Lecture 1

• symbiosis

  living together
• Phoresy

  travel together
• Commensalism

  eating at the same table
• Mutualism

  benefits to both
• Exploitation

  harm to one
• host fitness and niche

  host or external environment
• ectoparasites

  head lice
• endoparasites

  tapeworm
• hyperparasite

  parasite to a parasite
• accidental or incidental parasites

  not a regular host
• definitive host

  parasite shows sexual maturation
• intermediate host

  parasite grows and differentiates
• paratenic host

  parasite transport
• zoonosis

  human disease related to animals
• reservoir hosts

  sylvatic and domestic (dog)
• vector

  parasite infected insects
• population of biology of parasites

  all species of worms are harmful when present in massive numbers
• R selected species

  dN/dt = rN
• K selected species

  dN/dt = rN(K-N/K)
• intensity

  number that infect the host
• prevalence

  number of new infection per unit of time
• aggregated

  the non-random (non-uniform) distribution of parasites within hosts
• incidence

  number of new cases per year
• density

  percentage of white blood cells
• neural parasitology

  control minds
• brood parasitism

  birds
• sexual parasitism

  deep sea fish
• noma

  NTD; high mortality rate; in malnourished children in remote parts of africa (non-specific polymicrobial organism; food security)
• Types of NTDS

  parasitic helminth; parasitic protozoan; bacterial, fungal; viral and other NTDS
• NPIs

  chagas disease, cysticercosis, toxocariasis, toxoplasmosis, trichomoniasis (nonviral STD)
• NTD attributes

  • most prevalent among poor people
  • endemic in rural areas of low-income countries
  • ancient
  • chronic
  • disabling
  • high disease burden
  • low mortality
  • stigmatizing and poverty promoting
• DALY

  disability-adjusted life year

  = YLL + YLD

  1 daly can be thought of as 1 lost "healthy" year
• YLL

  years of lift lost

  premature mortality in the pop.

  number of deaths multiplied by the standard life expectancy at the age at which death occurs
• YLD

  years lost due to disability

  I x DW x L

  I= number of incident cases

  DW= disability weight

  L= avg duration of the case until remission or death (years)

  scale of 0. (healthy) to 1 (dead)
• N= number of deaths

  L = standard life expectancy at age of death in years
• Global Burden of Disease (GBD)

  • allows comparison among diff. diseases
  • allows disease comparison in regions and countries
  • helps government planning- health metrics
  • DALYs fro NTDs and 3 major infectious diseases (HIV/AIDS, malaria, TB) are comparable
• UN Millennium Development Goals

  • 8 goals
  • eradicate extreme poverty and hunger
  • combat HIV/AIDS, malaria, other diseases
• UN Sustainable Development Goals

  • 17 goals
  • end poverty in all its forms everywhere
  • ensure healthy lives and promote well-being for all at all ages
  • COVID has made more challenging
• Most Prevalent NTDs

  • ascariasis
  • hookworms
  • trichuriasis
• Emerging Diseases

  • west nile virus
  • ebola
  • COVID, SARS, MIRS
  • SARS-CoV-2