5 -

• Emerging Infectious Diseases (EIDs)


  • Newly emerging (newly appeared in a population)
  • Existing but rapidly increasing in incidence or geographic range
  • Re-emerging/new epidemics of old pathogens
• There's a dedicated journal that always seems to use classic artwork for Emerging Infectious Diseases
• Origin of EIDs


  • Pathogen type
  • Transmission type
  • Drug resistance
  • Transmission mode
• Jones et al. (2008) published a paper on global trends in emerging infectious diseases in Nature
• Factors attributed to emergence of infectious disease


  • Deforestation
  • Agricultural development
  • Urbanisation
  • Habitat fragmentation
  • Road construction
  • Air and water pollution
  • Climate change (see BS127)
  • Hydrological changes, dam building
  • Population movement
  • Drug resistance
  • Better detection/diagnosis
• Emergence (or re-emergence) could be due to improved diagnostic sensitivity, new diagnostics, improved education/reporting, or modified/improved classification
• There will always be some under-reporting of emerging infectious diseases
• Population movement/migration


  Can replenish susceptibles and introduce the index case of an infection
• For most of 200,000 years of humans, they didn't move much, but the last 100 years have seen 'time, travel and infection'
• There is a Y3 module called 'One World Health and Neglected Tropical Diseases' (LF307)
• Planetary Health seems to be the more accepted term than One World Health
• According to Rohr et al. (2019), ~25% of emerging human infectious diseases and ~50% of zoonotic emerging infectious diseases of humans are linked to global food production since 1940
• Cahora Bassa Dam in Mozambique


  Reduced downstream flooding and free standing water (reduced breeding sites), but created a large man-made 'stagnant' lake upstream - a perfect large scale mosquito breeding site
• The article on the effects of the Cahora Bassa Dam on malaria is on Moodle
• Measles


  • Morbillivirus with an R0 of approximately 18, one of the highest (non-VB)
  • Transmitted by droplet and aerosol
  • Death rate varies considerably dependent on healthcare access
  • 1 in 5 infected develop complications such as ear infections, Pneumonia, Encephalitis
  • Cheap and highly effective vaccine is available (MMR)
• In 2019, there were 869,770 global measles cases, a 556% increase on 2016, the most annual cases since 1996
• Measles Outbreaks


  • Ukraine - unrelated death following a vaccination lead to a loss of confidence in the vaccine, followed by armed conflict, vaccination levels were not sustained
  • Philippines - vaccine scepticism
  • DRC - cost, access, civil war
  • Madagascar - not high enough vaccination coverage (a post-honeymoon period) and only one dose
• Human behaviour is the main driver for emerging infectious diseases
• Public Health management and infectious disease intervention will require a One World/Planetary Health approach
• Changes to water bodies can increase the risk of malaria (and other diseases with arthropod vectors)
• Infectious disease control can be disrupted by a variety of things
• The behaviour driving emerging infectious diseases continues or increases