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Prevention

Ebola  is really quite a horrible little bit of DNA. Its route to humans is via the fruit bat and between humans through body fluids. So much for the public health model.

The virus is taking advantage of humans with poor lifestyle, illiteracy, folk medicine, weak healthcare systems and lack of awareness. If it is true a 2 year old is person zero, how did that come to be? The public health model wants to find the person, but what we really need to understand are the conditions for zero to become infected. That means mapping the ecology within which the virus operates.

The diagram proposes that outbreaks, epidemics, pandemics be understood as an ecology combining information, biological and social strands which track the infection production process.

pandemic map

Source: Tremblay, Scoping technologies for pandemics, obesity and counterfeit medicines, report for UK Department of Health, 2009.

We’re in the middle in the countries at risk of the Ebola outbread, and at the beginning everywhere else (even a case or two does not a crisis make). Nigeria may now be coming out the other end. The key is to build into our response an anticipatory and first response capacity throughout.

The real test of how these three countries will emerge from the Ebola crisis depends on what they are now putting in place for the Post-infection phase. Typically, events such as these emerge, get dealt with quite quickly (as in the case of other Ebola outbreaks), but building in anticipatory and response capacity is not a resulting priority. Better organised healthcare systems will handle situations like this better.

The three at-risk countries have weak governance, score low on Transparency International’s corruption scale, and low on WHO’s Human Development Scale, all characteristics of failing states.  It is not inconceivable that these countries could collapse; the historical record shows that other civilisations have collapsed from disease.

Since weak healthcare systems are contributive to the problem, improving access to care and reducing the cash component would require improving the economic performance of the country itself. That comes with greater trust in government and confidence in the future. So there are tools and techniques that can be deployed to help.

Consideration should also be given to more integrated, ecological models of how viruses and infections work, what some call “conservation medicine”. Many of the problems of pandemics arise from unnecessarily narrow specialised focus and adoption of particular disease transmission paradigms that marginalise knowledge in related areas.

Without being too draconian in this respect, some rethink is appropriate of the prevailing public health driven model, characterised by high degrees of alarmist rhetoric and hyperactivity, to achieve a measure of integration particularly around pinch points in the flow of information for effective decision-making.  A ‘systems model’ would start with the likely inaccuracy of diagnostic tools (which both over- and under-report). There is also a general weakness in animal and human disease surveillance and corresponding weaknesses in subsequent information management.  What we know from thinking like a virus is that humans can be just as dangerous as the bats that originate the virus, but we use different logic when dealing with humans as with the bats.

Compounding he problem with Ebola and other zoonoses of that type is that our ability to collect information and act is slower than the pace of spread.

Obviously screening people at airports makes sense within the public health model, but makes little sense from the point of view of the virus itself. Regretfully, quarantining whole countries may need to contemplated. Screening at airports does little when the origin is people arising from stricken regions. What do they say about closing the barn doors after the cows have left?

But we must learn how to think more like the virus, so we react more quickly, and ensure the virus will not have the opportunity to spread.  After all, that is what the virus wants to do.

About the three most at-risk countries

The countries that are the core to the current Ebola crisis are Guinea, Sierra Leone and Liberia. Using WHO Human Development data (from here), we learn that these three countries are classified as low development countries: Liberia is ranked 175, Guinea 179 and Sierra Leone 183; there are 187 countries on the list. They spend less than 3.0% of GDP on education (closer to 5% is associated with higher education attainment levels) and with literacy levels below 50%. Expenditure on health as a percentage of GDP shows they are essentially cash-based systems, which given the relative poor human development means access to healthcare will be income rather than need linked — they have health systems for those who can afford it. Transparency International ranks these countries toward the bottom (more rather than less corrupt) with scores below 30 (see here). All very worrisome but indicative of national priorities at odds with the needs of the country. Many are more prone to conflict than care.

From the point of view of a virus, these are excellent conditions for transmission: illiteracy, poverty, unhealthy population with low life expectancies (under 50 years or so), internal strife and conflict.

Guinea: spends 6% of GDP on health, of which 67.4% is cash

Sierra Leone: spends 18.8% on health, of which 74.9% is cash

Liberia: spends 19.5% on health of which 17.7% is cash (best of the three in that respect)

Want to know more?Laurie Garrett’s The Coming Plague, 1994. See here at Garrett’s website. And they say prophecy is dead.

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