Icebergs are dangerous because so much of their mass lies below the waterline. Similarly, we must consider the COVID iceberg in the same way.

We are currently finding COVID virus infected people who have symptoms — the COVID iceberg that we can see. A much larger mass of COVID lies unseen below the waterline — those infected people who are not sick and may never be sick, but are capable of infecting those around them. It is all one COVID iceberg! We should all beware.

My friend is a 69-year-old woman who works in a distribution company which practices social distancing but does not require masks. One of the workers tested positive for COVID-19 last week, so all were sent to be tested. Most returned without being tested, having been told that since they did not have symptoms, they did not need the test. How many of those workers were infected with the virus causing COVID-19?

Why is this strategy so flawed? There is abundant evidence from recent scientific publications that the COVID spreads silently among those without symptoms. Persons who will be sickened by the virus usually have symptoms within five to 14 days of exposure. More people with COVID have no symptoms, although chest X-rays show lung changes in many of those silently infected.

Both those with symptoms and those without symptoms can spread virus for up to 21 days. The amount of virus shed from either group is the same. Like the iceberg under the water, asymptomatic infected people are not obvious and are frequently not tested.

Spread of COVID 19 by those without symptoms is highlighted in data from the Navy aircraft carrier USS Theodore Roosevelt where 94% of the sailors were eventually infected despite isolation of the small number of those with obvious illness. Sixty percent of those infected never had symptoms but were found to continue to shed virus. How might these numbers have changed if all had been tested when the first infected person was discovered?

Vietnam is a good example of a consistent effective testing strategy. Vietnam has 97 million people and only 327 cases of COVID-19 as of May, 2020, and no COVID deaths. Many factors contributed to this successful control of COVID-19.

Success came, according to one report “from mobilizing citizen awareness of disease prevention without spreading panic, via fostering genuine cooperation between government, civil society, and private individuals.”

Contact tracing of those infected was thorough and complete and included all who were exposed, not just those with symptoms. Isolation of all positive cases occurred. Everyone wore a mask in situations of close contact. Life is returning to normal in Vietnam.

What else can be done to prevent the spread of the virus from those without symptoms? We can all wear masks. Wearing a mask is not a political statement. It is a way of showing concern for other citizens by helping us all to prevent spread of the virus. If everyone meticulously wore masks in any situation where social distancing was not possible, the virus spread would dramatically decline and businesses could remain open.

Individuals in Vietnam wear masks to prevent the spread of infection, and their lives are returning to normal much faster than ours. We would all feel much safer and thus be more willing to engage in business functions or buy services. Recent government actions promoting or requiring masks is a step in the right direction.

We need to deal with the whole iceberg to avoid danger and the fear it produces. Do we have the courage to act and take care of our community with masks and access to testing? I hope so.

Elizabeth H Hammond

Elizabeth Hammond, M.D., is a consultant pathologist at Intermountain Healthcare and emerita professor of pathology and adjunct professor of internal medicine (cardiology) at the University of Utah School of Medicine.