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More people caught in the Immunity Trap in 2016

December 20, 2016 - 21:15 -- William Jobin

The WHO Malaria Report for 2016 mentions an alarming increase in the number of people no longer receiving protection from indoor spraying, and thus an increase in the number of people in endemic areas who have lost their immunity, due to previous intense spraying. For Africa, 10.5% of the populations were covered in 2010, but this had dropped to 5.7% by end of 2016.

The simple explanation that the reductions in coverage was due to cessation of spraying with pyrethoids, obscures the real reason, the increasing cost of new insecticides as the mosquitoes become resistant to the older and cheaper pyrethroids. Bendiocarb is now in use, so expensive that Angola has stopped spraying altogether, despite the initial success in 2005 when we started the US PMI there in southern Angola.

I quote the WHO report for 2015:

■ IRS is generally used by NMCPs only in particular areas. The proportion of the population at risk protected by IRS declined from a peak of 5.7% globally in 2010 to 3.1% in 2015, and from 10.5% to 5.7% in sub-Saharan Africa.
■ Reductions in IRS coverage may be attributed to cessation of spraying with pyrethroids, particularly in the WHO African Region.

But what is missing from this summary is that the people no longer covered have lost their immunity, and are thus at risk of severe disease.

In her report, Dr. Chan says, "We have made excellent progress, but our work is incomplete. Last year alone, the global tally of malaria reached 212 million cases and 429 000 deaths. Across Africa, millions of people still lack access to the tools they need to prevent and treat the disease."

Is that excellent progress?

Or is it just more fumbling in the dark?

So when is WHO going to get smart and get off the Resistance Treadmill, and instead using permanent environmental and housing improvements? We recommended this to WHO and the US PMI in 2005. That was a decade ago. It should be obvious to the folks in Geneva and Washington DC by now.

Bill, frustrated and irritated at the lack of global vision in WHO and US PMI