According to news reports, more than 170 sailors on board the USS Theodore Roosevelt (CVN-71) have been identified as infected with SARS-CoV-2. I write this as a physician and retired naval officer (and not as a representative of the U.S. Government, the Department of Defense, or the Defense Threat Reduction Agency) who served 32 years, first in naval aviation and then Navy medicine, who reluctantly retired in 2002. I love the Navy and want to help. I have absolutely no idea what guidance ship captains have been given, nor do I have the right to know. And I certainly have no desire to interpose myself between those captains and their higher authority.
But I write to say that mission versus safety is not a binary choice.
Extraordinary accommodations can be taken against SARS-CoV-2 and COVID-19 while still maintaining mission readiness, especially in port. I dodged a question about this during a recent Proceedings Podcast out of deference for Navy leaders. My recommendations herein might be seen as naïve, or too simplistic. My hope is they are not.
First, realize that while sailors and Marines may contract COVID-19, most will have mild or even no symptoms. Consider that researchers tested the entire population of Vò, Italy (3,300 people) and found more than half of those who tested positive were asymptomatic. The Director of the U.S. Centers for Disease Control recently estimated that up to 25 percent of those infected with the virus may be totally asymptomatic. Data from South Korea and elsewhere indicates that while among the general population the case fatality rate (CFR: deaths divided by total known cases) could be high, the CFR among those under 50 is less than 0.1 percent (1/1000) and almost no deaths occurred among those younger than 30. The incidence of complicating comorbidities such as diabetes, uncontrolled hypertension, obesity, and cardiovascular or pulmonary disease is essentially nil among the active duty population, which is not true among the population at large. Similarly, the incidence of moderate disease requiring hospitalization (15 percent) and severe disease requiring ICU admission and probable assisted ventilation (5 percent) should be significantly lower among active duty personnel compared to the general population. These percentages would likely be much lower if the actual prevalence of infection (symptomatic and asymptomatic) were known with certainty.
So, what is the worst-case scenario on a fully loaded aircraft carrier with an embarked airwing—roughly 6,000 sailors and Marines? My crude estimate is that 80 percent of those embarked are under 30, at most 15 percent are between 30 and 50, at most 5 percent (the senior officers and enlisted leaders) are over 50, and none are over 60. Even if everyone embarked were to become infected with SARS-CoV-2, likely less than 10 percent would develop symptoms severe enough for hospitalization, an order of magnitude less would become seriously ill, and, if afforded judicious treatment, very few—if any—would succumb to their illnesses. A significant but unknown number also would likely be infected but totally asymptomatic or only have mild symptoms and could fulfill their duties.
All that being said, service members’ lives are precious, and we should do everything in our respective powers to protect the lives and health of our shipmates. With that, if I were on active duty and advising a carrier’s skipper, these would be my recommendations:
1. The first, and seemingly most obvious, option would be to offload the airwing. It would reduce the population at risk by about 40 percent. But it would be extraordinarily challenging logistically, especially far from the ship’s homeport, and would effectively eliminate mission capability. And it would not, by itself, solve the problem. And, if any in the airwing were presymptomatic or asymptomatic carriers, it would just transfer the problem elsewhere.
2. A second option, which would solve the problem, might be even more logistically challenging, and would temporarily eliminate mission capability. Go cold steel and evacuate the ship except for a skeleton crew. Have 100 percent of the crew tested twice, at least 24 hours apart. Although viral RNA was found on cruise ships after 17 days, studies have demonstrated that viable viruses survive up to three days on plastic and stainless steel, and less on other surfaces. Cleared crew could return to the ship safely after four days ashore.
Assuming these two radical options are rejected, there are a full gamut of actions that can collectively mitigate the outbreak:
1. Offload all the positive cases, if not done so already, to the nearest military (or civilian) hospital.
2. Immediately deep clean—using ultraviolet lights, if available—the work centers of those individuals, the most likely restrooms/heads used, and of course the proximate areas of berthing spaces. Deep clean all messes. Collect and double bag all personal effects, which should be assumed to be contaminated.
3. Offload at least 20 percent of the crew, more if possible. This should not seriously degrade mission essential capabilities and would provide a source for immediate backfill if others test positive.
4. Offload anyone more than 10 percent overweight, who has poorly controlled hypertension, or who is pregnant. For other conditions, such as recent pneumonia, consult your medical officer.
5. Anyone over 50—including the CO—needs to work remotely, from his or her stateroom or, ideally, from a secure area on shore. No one over 50 should be in general berthing. If self-distancing on board, maintain that posture except when absolutely necessary, and use additional precautions (see below) when out and about.
6. All crew should check their symptoms daily and contact medical if they have any suspicious symptoms. Use https://c19check.com (or one of the other free symptom checker apps). If the crew member gets a yellow on the checker, he or she should be tested as soon as possible. Sailors getting a red on the checker should be quarantined until cleared by medical authority or until receiving two negative test results more than 24 hours apart.
7. All crew must wear masks, preferably surgical ones (but cloth masks or even bandanas if those are the only options) at all times unless they are in the shower, eating, or in a private stateroom. There are studies that demonstrate some protection afforded through mass masking. (The CDC is currently reconsidering its original position on mass masking, and several U.S. communities have begun recommending this). Mass masking:
a. Reduces (but does not eliminate) the potential for an asymptomatic but infected individual spreading the virus to others through airborne.
b. Reduces (but does not eliminate) a healthy person from inhaling airborne viruses from others.
c. Serves as a constant reminder to social distance, not touch face, and wash hands.
d. Because people unconsciously touch their faces more than 15 times per hour, a mask in place will prevent direct contact with nares or lips, and may reduce, but not totally eliminate the possibility of self-infection.
e. When the mask comes off, it goes right into a bucket, for disposal or cleaning. A cloth mask can be sent to the ship’s laundry. A surgical mask can be disinfected by dry heating to 158°F (70°C) for 30 minutes, hot water vapor from boiling water for 10 minutes, or high intensity UV light for 10 minutes.
f. Wash hands before and right after donning and wash hands and face after doffing.
8. Reduce the focal points. Eliminate 2/3rds of the chairs in dining facilities and stretch out the hours of operation so there is not a concentration there. Nobody should be able to sit closer than 6 ft from other, and that distance should be maintained in chow lines.
9. Deep clean:
a. Dining table surfaces and chairs after every use.
b. All handles and door knobs every two hours.
c. All heads every four hours.
d. All commonly used surfaces, switches, keyboards, the helm, etc., at each change of watch.
10. Increase flow rate of ship ventilation systems if possible, to reduce the concentration of any airborne particles and aerosols.
11. Establish, to the greatest extent possible, unidirectional passageways and ladders. Port up/aft, starboard down/forward. It will take longer to get around ship but will reduce possibility of transmission while passing other crew members.
12. If any new cases appear, immediately quarantine, preferably on shore or in a dedicated space on board, pending disposition. Attempt to contact-trace other crewmembers in proximity during the previous 24 to 48 hours. Such contacts should probably be quarantined as well, and can be replaced with backfill from shore until cleared by medical authority.
13. Constantly reinforce social distancing and personal hygienic practices. Stay away from others, wash your hands frequently, do not touch your face or eyes, cover your cough and sneezes.
If these guidelines are strictly adhered to, the rate of infection will be low or may stop altogether. Realize, however, that even with these precautions, additional crew might still contract the virus. Again, few will become seriously ill, and even fewer are at risk of death.
Those who contract the disease and recover will likely be immune and may subsequently serve as convalescent sera reservoirs. Convalescent sera—extracted antibodies from the blood of recovered infection victims—have been used for more than 100 years for various viral infections, including influenza, measles, mumps, polio, and Ebola. It worked then; it should work now.
Mission readiness and crew safety are not mutually exclusive.
