The effect of the 1918 influenza pandemic on other diseases is a neglected topic in historical epidemiology. This paper takes up the hypothesis that the influenza pandemic affected the long-term decline of tuberculosis though selective mortality, such that many people with tuberculosis were killed in 1918, depressing subsequent tuberculosis mortality and transmission. Regularly-collected vital statistics data on mortality of influenza and tuberculosis in the US are presented and analyzed demographically. The available population-level data fail to contradict the selection hypothesis. More work is needed to understand fully the role of multiple morbidities in the 1918 influenza pandemic.

Background: Divergence of male and female life expectancy is a well-documented phenomenon. Comovement is a heretofore-neglected aspect of changes in male and female mortality. Objective: We develop a new framework for life expectancy sex differentials in time series, using co-movement/anti-movement and convergence/divergence. METHODS We apply this framework to the Human Mortality Database (HMD), assessing co-movement between male and female life expectancy with the nonparametric test of Goodman and Grunfeld (1961). Results: For every country in the HMD (except three with short spans of data), male and female mortality statistically co-move. This applies even in cases, including ones such as Russia that are well-discussed in the literature, that show extreme divergence between the sexes. The results are reasonably robust to subsetting with a 25-year time-window for all countries. Conclusions: Male and female life expectancy co-move even when the life expectancy sex differential increases. The sex divergence in life expectancy needs to be (re-)considered in light of the fact that male and female life expectancy usually co-move, reflecting overall societal factors.

We analyze lung cancer mortality by age and sex in the United States, 1959-2013. It is already known that male lung cancer death rates exceed those of women and that tobacco use is the leading reason for the sex difference. We elaborate on this knowledge by showing that unlike most causes of death, lung cancer mortality patterns by age are a very good fit to a quadratic-Gompertz model, i.e., log mortality rates are quadratic by age, with the mode above age 70. With a little additional historical data on sex differences in tobacco use, the quadratic models help to paint a clear quantitative picture of behavior-led convergence in lung cancer mortality by sex. The shape of the sex-specific mortality curves have converged dramatically: since 1983, the sexes have had statistically indistinguishable shapes of their quadratic-Gompertz mortality curves. Female lung cancer mortality patterns have shown a transformation from a nonsmoking to a smoking pattern. The modal age of the quadratic-Gompertzian lung cancer death rates has potential application in countries at earlier stages of the global tobacco epidemic. Where the modal age is falling (year-on-year), we can infer that the local lung cancer epidemic is getting worse, and where it is rising, that it has begun to abate.

BACKGROUND In temperate climates, mortality is seasonal with a winter-dominant pattern, due in part to specific causes of death, including pneumonia, influenza, and cold-induced thrombosis. Cardiac causes, which are the leading cause of death in the United States, are winterseasonal, although the pathways are incompletely understood. Interactions between circulating respiratory viruses (e.g., influenza) and cardiac conditions have been suggested as a cause of winter-dominant mortality patterns. OBJECTIVE In this paper we aim to quantify the total mortality burden of winter in the United States. METHODS We calculate 'pseudoseasonal' life expectancy, dividing the year into two six-month spans, one encompassing winter, the other summer. RESULTS During the summer when cold weather is absent and the circulation of respiratory viruses is significantly reduced, life expectancy is about one year longer. We also quantify the seasonal mortality difference in terms of seasonal 'equivalent ages' (defined herein) and proportional hazards. CONTRIBUTION We quantify the effects of winter mortality. The population-level mortality reduction of a perfect influenza vaccine (which can only reduce a portion of winter-attributable mortality) would be much more modest than is often recognized.

An EVD outbreak may reduce life expectancy directly (due to high mortality among EVD cases) and indirectly (e.g., due to lower utilization of healthcare and subsequent increases in non-EVD mortality). In this paper, we investigated the direct effects of EVD on life expectancy in Liberia, Sierra Leone and Guinea (LSLG thereafter). We used data on EVD cases and deaths published in situation reports by the World Health Organization (WHO), as well as data on the age of EVD cases reported from patient datasets. We used data on non-EVD mortality from the most recent life tables published prior to the EVD outbreak. We then formulated three scenarios based on hypotheses about a) the extent of under-reporting of EVD cases and b) the EVD case fatality ratio. For each scenario, we re-estimated the number of EVD deaths in LSLG and we applied standard life table techniques to calculate life expectancy. In Liberia, possible reductions in life expectancy resulting from EVD deaths ranged from 1.63 year (low EVD scenario) to 5.56 years (high EVD scenario), whereas in Sierra Leone, possible life expectancy declines ranged from 1.38 to 5.10 years. In Guinea, the direct effects of EVD on life expectancy were more limited (<1.20 year). Our high EVD scenario suggests that, due to EVD deaths, life expectancy may have declined in Liberia and Sierra Leone to levels these two countries had not experienced since 2001-2003, i.e., approximately the end of their civil wars. The total effects of EVD on life expectancy may however be larger due to possible concomitant increases in non-EVD mortality during the outbreak.