Comparing 2019 and 2020 mortality in rural Bangladesh in relation to COVID-19 and arsenic exposure

Abstract:

The first three known COVID-19 cases were reported in Bangladesh on March 7, 2020. Eight months later, the total official is 430,000 cases while the number of deaths attributed to COVID-19 is a relatively modest 6,140 given the country’s population of 160 million. In order to determine if these numbers might be underestimates and to gauge potential interactions between COVID-19 and drinking well water containing arsenic, we launched phone surveys of 16,058 households distributed across 135 villages of Bangladesh that had been visited a first time in January 2020 to conduct a census for a different study. Two cell phone numbers were recorded for each household at the time. The 14775 households (92% of the total) that could be reached in May 2020 reported a total of 477 deaths in 2019 for a total population of 67,454. The corresponding crude mortality rate of 7.1 per 1000, which is somewhat higher than the 5.5 per 1000 figure for the country overall. Deaths reported by the same households for the first 4 months of 2020 correspond to a mortality rate of 6.8 per 1000 that was lower than in 2019. There was no striking difference between the two years in the distribution among different causes of death, self-reported in broad categories, the distribution of ages at death, or the location of death. At the time of submitting this abstract, one third through a second phone survey of the same households, the annual mortality rate since May was even lower at 6.1 per 1000. Information about recent deaths was elicited from households by conducting each time a household census over the phone rather than by asking directly, as way of reducing the likelihood of under-reporting. If these surprising findings can be confirmed, they would suggest that the net impact of COVID-19 in Bangladesh has been to reduce rather than increase mortality, presumably due to public health campaigns to limit contact and movement (and therefore road accidents). When field activities resume, hopefully in Spring 2021, all 12,000 wells in the study village will be tested for arsenic and are anticipated to span a wide range of concentrations. By combining phone and field surveys, we will be uniquely positioned to ascertain if the known impact of arsenic exposure on the immune system translated into differential responses to COVID-19.