Mortality Risk of Men vs. Women: Implications for a Vaccination Plan

On January 15, 2021, the Oregon Governor announced a revised Covid-19 vaccination sequencing plan that includes vaccination of Oregon’s seniors.  Phase 1a of the State’s plan qualified health care workers to receive vaccines, as well as those in long-term care settings.  Individuals in this phase are currently being vaccinated.  

The first group to qualify under Phase 1b of the plan will be teachers and childcare providers, on January 25th.  Beginning Feb. 8, seniors are scheduled to be eligible for vaccination in four additional groups:  seniors 80 and older first; followed later by seniors who are 75 and older; then seniors who are 70 and older; and  lastly, Oregonians 65 and older.  

According to the latest information from the Oregon Health Administration, due to vaccine supply constraints, it will take 15 or more weeks (instead of the planned 5 weeks) to vaccinate the five Phase 1b groups—assuming supplies materialize.

Given the uncertainty of vaccine supplies, it is crucial that the focus of vaccination reflect accurately the Covid-19 mortality risk faced by seniors.  Unfortunately, the current plan implicitly assumes that the risk of death from Covid-19 for seniors increases only with age.  Thus, the vaccination sequencing focusses on the most elderly first.  This ignores completely the fact that gender is far more important, in terms of focusing on relative risk exposure, than simply age per se.  

Although men and women are at similar risks of infection by Covid-19, men are far more likely to be killed by it.  For example, a recent worldwide meta-analysis of over 3 million Covid-19 cases found that men are almost 3 times more likely than women to require admission to an intensive care unit (ICU).  The same study found men to be 1.4 times as likely to die from Covid-19, on average across all age groups. 

Age-Specific Relative Risks

But such average risk measures conceal the higher risks that gender adds at every age cohort.  There are approximately 600,000 Oregon men in the 4 senior cohorts tabulated below.  As the table indicates, male seniors face a mortality risk that is as much as 3.3 times that of their female counterparts. This pattern is true nationally, but is especially stark in the Oregon data.  

Using the US data, the male/female mortality ratios on an age-weighted basis is approximately 1.72 across the whole population.  It is interesting to compare this population-wide measure to similar measures by race and ethnicity groups.  Some are known to face greater risks than non-hispanic white persons. Indeed all but the Asian group have higher risks—by about 50%—than non-Hispanic white persons at a population level.  However, the risk ratios are not as stark as male/female ratios of seniors by age group.  

Benefits of Gender Adjustment of Mortality Rates

At present, there is implicitly higher priority given to lower-risk individuals because of the reliance on age-based prioritization alone. Correcting this gender-based disparity will improve the focus on some of the most at-risk Oregonians, which is the objective of the immunization plan. 

Doing so will benefit not, however, benefit just the vaccinated men.  For example, vaccinating senior men will benefit all users of hospital and ICU capacity.  Since men are almost 3 times more likely to require scarce and costly hospital ICU services, a vaccine that eliminates men’s risk of infection  and hospitalization will reduce these burdens.  

Everything else being equal, vaccination of a senior male will reduce ICU and hospital services demand by three times that of a vaccinated female of similar age.  This benefits all potential hospital patients—both Covid-19 and non-Covid-19 patients, and affected ethnic males who also may comprise the senior male group.    

Incorporating gender in the prioritization process will help to address another health disparity.  There are several biological reasons that Covid-19 is more dangerous to men.  These same factors appear to be associated with men’s relatively short life expectancy.   On average men have a 5-year disadvantage in life-span over women, independent of Covid-19.  Indeed, there are already about 90,000 fewer Oregon men than women in the senior cohorts identified in this study. Prioritizing men for Covid-19 helps to offset that health disparity to some degree.  

Ideally, the rationing of vaccines and associated sequencing of vaccinations would be unnecessary.  However, there are long delays anticipated for receipt of vaccine supplies.  Elderly men will pay the price of the poor design of the vaccination plan.    

Use Masks, not Lock Downs, to Stop the Covid-19 Pandemic

When the Coronavirus arrived in the US, there was a rush by the public to acquire face masks. After all, the Coronavirus was a pathogen that caused disease by getting into the lungs by inhalation or by touching contaminated hands to the mouth, nose, or eyes. Face masks have the potential to filter particles and to deter touching one’s hands to the face. Wearing face masks thus seems a natural thing to do.  

However, health policy officials chastised them and told them to stop buying masks. For example, the US Surgeon General tweeted on February 29, 2020, saying: 

“Seriously people - STOP BUYING MASKS! They are NOT effective in preventing the general public from catching Corona virus, but if healthcare providers can’t get them to care for the sick patients, it puts them and our communities at risk!”~Dr. Jerome Adams, US Surgeon General. 

Apparently, health "experts" believed that transmission to others involved symptomatic individuals with viral particles in their sneezes and coughs. The resulting sharp bursts of droplets contaminate the hands and belongings of the affected individual and collect on doorknobs, furniture, clothing and other surfaces. Hence, initially the public was only advised to wash hands and disinfect contaminated surfaces.  

The snag in this logic is that virus transmissions from asymptomatic, but infected individuals, had been identified in the case of Coronavirus (Rothe et al. 2020), and found to be as much as 80 percent of all infections of others (Li et al. 2020). In March 2020, a summary of research on the mobility and characteristics of flu particles was published in the journal Aerosol Science and Technology. That literature made it clear that the Covid-19 particles of symptomatic and asymptomatic people were of the appropriate small size and persistence in the air to be inhaled deeply into the respiratory tract.

This is precisely the set of circumstances, of course, that wearing a mask to protect the wearer could have great benefit. The virus particles (or an important share of them) could be kept from entering the respiratory tract of the wearer. The importance of having the public wear masks is that the masks affect a pandemic at the virus’ first point of contact with people. Therefore, masks have the potential to immediately arrest the process that can cause the number of cases and deaths to grow out of control. 

Health officials chose, instead, to practice social distancing. Unfortunately, this has meant shutting down many business and social activities. Some activities can be replicated by internet conferencing, but in the US, social distancing resulted in the closure of schools and increased the nation's unemployment rate to over 14 percent.

Japan’s experience with Coronavirus was very differemt.  The Japanese public have a tradition of wearing masks every fall influenza season. Japan services this need by manufacturing 1.3 billion masks per year. At this writing, Japan has only one Coronavirus case for every 13,000 persons, versus the US with one per 500 persons. Japan also has a much lower death rate, at one death per 666,000 persons versus one death per 58,600 persons in the US). By these metrics, whatever the Japanese are doing is 26 to 77 times the US approach. 

In addition, of course, the Japanese are not bearing the economic disruption that the US, the UK and others are suffering from the comprehensive social distancing policies.  In contrast, at the theoretical extreme, effective masking could, by itself, not only control further spreading or rebound infections by Covid-19, but also control potential de novo or mutant airborne influenzas. Thus, a combination of comprehensive use of masks, frequent, periodic random testing to monitor the level and distribution of infection, and careful screening of US border crossings may be all that is needed going forward. It is also policy that can be activated and deactivated to quickly adjust to conditions.

Sources: 

Asadi, Sima, N. Bouvier, A. S. Wexler, W. D. Ristenpart. 2020. “The Corona Virus Pandemic and Aerosols: Does COVID-19 Transmit via Expiratory Particles?” The Journal of Aerosol Science and Technology; Li, R., S. Pei, B. Chen, Y. Song, T. Zhang, W. Yang, and J.Shaman. 2020. “Substantial Undocumented Infection Facilitates the Rapid Dissemination of Novel Coronavirus (COVID-19).” Science. Rothe, C., M. Schunk, P. Sothmann, G. Bretzel, G. Froeschl, C. Wallrauch, T. Zimmer, V. Thiel, C. Janke, W. Guggemos, et al. 2020. “Transmission of 2019-nCoV Infection from an Asymptomatic Contact in Germany.” The New England Journal of Medicine. 382 (10):970–1.