Remarkable rates of lightning strike mortality in Malawi

Abstract

Livingstone's second mission site on the shore of Lake Malawi suffers very high rates of consequential lightning strikes. Comprehensive interviewing of victims and their relatives in seven Traditional Authorities in Nkhata Bay District, Malawi revealed that the annual rate of consequential strikes was 419/million, more than six times higher than that in other developing countries; the rate of deaths from lightning was 84/million/year, 5.4 times greater than the highest ever recorded. These remarkable figures reveal that lightning constitutes a significant stochastic source of mortality with potential life history consequences, but it should not deflect attention away from the more prominent causes of mortality in this rural area.

Figure 1. Household interviews were conducted to catalog the consequential lightning strikes in seven Traditional Authorities (TAs) of Nkhata Bay District, fringing the western shore of Lake Malawi.

TA boundaries correspond to the period of 2008; Mankhambira TA shown here overlaps the urban TA of Mkumbira (not pictured), which comprises Nkhata Bay Town but was not surveyed. During sampling, Fukamalaza was combined with Malanda TA.

Figure 2. Estimates of mortality from lightning per million people per annum.

Data are taken from Holle and were compiled from published estimates, except for Malawi (this study) and Swaziland . Selected data include historical estimates to approximate rates in 1900 (+/− 30 yrs). All mortality rates reported for current temperate countries are less than 1.0 per million people per annum.