Current Situational Map of the Haiti Cholera Epidemic

UPDATES:

• Added second map to highlight vectors of potential concern- i.e. lines of disease introduction from starred sites reporting cholera activity.
  

Please note the below is a map not of case counts, but of sites in Haiti where we now assume or have confirmed the presence of cholera.  From an operational biosurveillance perspective, we are now singularly focused on local capacity to provide appropriate medical care to avoid unnecessary loss of life in the context of social stability.  The Infectious Disease Impact Scale (IDIS) is used for this purpose:

• IDIS Category 0.  Unreported infectious disease event.  Daily, routine infectious diseases are handled at this level, and provision of warning about these diseases is not deemed ‘relevant’. It is likely there are multiple unreported cholera cases now inside Port-au-Prince, for instance, and in Artibonite and perhaps elsewhere.
• IDIS Category 1. Reported infectious disease event. The typical Category 1 infectious disease event reported by a community reflects a sensitivity to public health or medical significance. No other significant features indicative of immediate public health or medical infrastructure impact, public anxiety, or civil unrest triggered by the event are noted.
• IDIS Category 2. Infectious disease event associated with routine organized response. Category 2 events often reflect locally well-known diseases that nevertheless generate a demand for organization-level time-sensitive action. This action is local routine.
• IDIS Category 3. Infectious disease event associated with non-routine organized response. Category 3 events are essentially the beginnings of a community crisis.
• IDIS Category 4. Infectious disease event associated with social disruption. Category 4 events highlight when organized response has occurred, yet significant social disruption has been documented.
• IDIS Category 5. Infectious disease event associated with disaster indicators.
• IDIS Category 6. Infectious disease event associated with apocalyptic indicators.  This is an operationally rare finding, associated historically with Ebola and Nipah virus outbreaks.  We do not consider this category to represent a likely scenario in Haiti.

Below is a situation map based on available information as of the moment of this posting.  We welcome and encourage our partners in the Twitterverse, HEAS partners, and colleagues we've yet to meet to provide insight into the situation.  We have posted the key guidelines that inform these categorizations earlier today. 

We sincerely thank the HEAS partnership community and the Twitterverse who have contributed to better situational awareness.

 

Current Situation Map of the Haiti cholera epidemic based on IDIS Category.  As noted, there remains much uncertainty as to the status of several specific local communities' capacities to handle patient demand.  IDIS Cat 3 conditions in Port-au-Prince indicate awareness of an influx of confirmed cholera cases; organized response is currently being cued by awareness of preceding events in Artibonite, whereas cholera was unexpected in Artibonite, which arguably hindered rapid alerting and response. 

Red arrows denote apparent vectors of cholera case influx from the original epidemic zone in Artibonite.  Northernmost lead edge is within proximity to Cap Hatien, southernmost is Port-au-Prince, and although a single case was reported there, the Director of LNSP has indicated the laboratory tests were NEGATIVE.  Given the increase in cases reported in Gonaive, it may be assumed more suspect cases will be seen in Cap Hatien.  We have no report of confirmed cases in Leogane or Nippes Department despite suspect cases reported there.  There remains the possibility of containment / protection of expansion to the Grand South.

Strategic Response Map (focusing on the greather Port au Prince area).  Blue arrows denote possible introduction vectors along key roadways, where infected people or contaminated goods may enable expansion of the cholera-affected areas.  Red stars are selected sites of interest reporting cholera.  There remains opportunity to inhibit flow of disease into Port au Prince, as well as prevention of introduction to Cite Soleil and Leogane.

Comments

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[RoMar]

An excellent site, thanks! A possibly helpful situational mapping tool is at http://www.noula.ht (I believe it's in French. For English, press the US flag at the top right.) Filter on "Health." I believe it is based on the Ushahidi model, which receives crowd-sourced reports via SMS text. If noula.ht is not yet using IDIS coding, I imagine that IDIS could be added to their process (or added to their data after the fact?).