Facemasks not only prevent the spread of covid-19 but can reduce symptoms in the event of infection. The individual benefit of wearing a mask may be an added incentive to use it and become a mainstay of the control of the covid-19 pandemic.
MEXICO (Journal of General Internal Medicine) Mexico has more than 53 thousand deaths, and AMLO still refuses to wear a face mask. The argument has become widespread from health authorities and governments around the world that recommend and/or impose the use of masks because they prevent infected people from spreading the coronavirus. Not for the Mexican president.
A new study in the Journal of General Internal Medicine concluded, after examining several cases, that wearing masks reduces the viral load to which we would be exposed and, if we became infected, the manifestation of the disease would be milder or even asymptomatic.
Research conducted in the United States by Drs. Monica Gandhi and Eric Goosby, from the University of California, and Dr. Chris Beyrer, from Johns Hopkins University, highlights that exposure to the coronavirus without severe consequences due to the use of masks could generate immunity at the community level and reduce the spread. At the same time, a vaccine against the virus is being developed.
In light of the rejection of mask use by some groups and individuals, the benefit to the individual (and others) who wears the mask suggested by the study could be an added incentive to use it and become a mainstay of pandemic control. The mask reduces the chance of having severe symptoms of covid-19, the researchers say.
The Effect of Viral Load
Drs. Gandhi, Goosby, and Beyrer support their theory, as they call it, by comparing the evidence from multiple situations in which groups have worn or stopped wearing masks and the relationship that this has to viral load and increased rates of mild or asymptomatic infections.
Asymptomatic infection can be problematic because it promotes the spread of the virus by people infected without knowing it. At the same time, being asymptomatic rather than seriously ill is beneficial to the individual, they say.
Besides, higher rates of asymptomatic infection lead to higher rates of exposure to the virus. Exposing a society to this coronavirus without the consequences of serious illness could create higher levels of community immunity, so-called herd immunity. Herd immunity”: why hundreds of scientists are critical of the British government’s strategy in dealing with the coronavirus outbreak
Researchers acknowledge that antibodies and T-cells’ immune response to different manifestations of covid-19 is still being analyzed. Still, signals based on the data of the development of such cellular immunity, even with a mild infection, are encouraging.
The perspective that carriers of masks are exposed to a lower viral load resulting in a milder infection is supported by the study of three crucial evidence: virological, epidemiological, and ecological.
Concerning the first, masks – depending on design and material – filter most, but not all, viral particles. It has been proposed that exposure to such low levels of viral particles is likely to result in less severe disease. Past experiments with humans exposed to different volumes of the non-lethal virus showed more severe symptoms in subjects who received a higher viral load.
With the new coronavirus, experimentation is neither possible nor ethical. Still, tests on hamsters in which the use of masks was simulated by separating the animals with a dividing wall made of a surgical mask showed that the protected hamsters were less prone to infection. Still, those among them who were infected with covid-19 showed mild symptoms.
In terms of epidemiological evidence, doctors indicate that the high mortality rates at the start of the pandemic appear to be associated with intense exposure to high viral load before mask use was introduced.
One recent case, particularly, stands out: a cruise ship in Argentina where all passengers and crew members were fitted with masks after an outbreak of covid-19 was detected. In that closed environment, 128 of the 217 people on board tested positive for coronavirus. However, the majority of those infected (81%) remained asymptomatic.
Mortality rates have remained low in countries that have reopened but still use masks. As ecological evidence, the research indicates that countries and regions already accustomed to using masks for infection control, such as Japan, Hong Kong, Taiwan, Singapore, Thailand, and South Korea, have not suffered as much in terms of disease severity and mortality.
The same has been true for countries that applied the mask measure early on.
Moreover, even though these countries experienced a resurgence of covid-19 cases as social and economic activity resumed, mortality rates have remained low, supporting the viral load theory, the study authors say.
In conclusion, the doctors argue that the universal use of masks during the pandemic should be one of the most critical foundations in controlling the disease and advocate that this measure be taken mainly in the United States, where the directives have not been homogeneous. Part of the population has even reacted violently against the use of masks.
They point out that during the devastating flu pandemic in 1918, Americans smoothly adopted the use of masks in public. Still, the response to the current Centers for Disease Control (CDC) recommendations has been uneven. In 1918, the American people had no objection to the use of masks to combat pandemic influenza.
The use of facemasks has two advantages. The first is to protect others by preventing the spread of the virus by an infected person. If that concern for others is not enough, perhaps the second advantage – individual benefit – is a more compelling motivation.