A joint public health investigation from the Navy and Marine Corps Public Health Center, in cooperation with the Centers for Disease Control, released their findings about how the Corona Virus affected the crew of the USS Theodore Roosevelt.
The investigation of the outbreak asked volunteers to complete a survey and provide a voluntary blood and nasal swab sample. Antibody testing was done on almost 400 crew of the TR, showing that 62 percent were infected with the Virus with mild symptoms. This is the first report published by the CDC on this demographic of young adults.
382 service members gave blood samples and a subset provided 267 nasal swab samples. The blood samples were tested for the presence of antibodies, meaning they had been exposed to the virus. Positive blood samples were tested further to determine their ability to prevent infection by neutralizing the virus. The nasal swabs were used to look for virus RNA (ribonucleic acid) which is genetic material.
Numerous human diseases are caused by RNA viruses including the common cold, influenza, SARS, COVID-19, hepatitis C, hepatitis E and several others.
Study participants also completed a questionnaire that included data on demographics, exposures, protective behaviors service members engaged in, health history, symptoms, and self-reporting of previous Corona Virus tests.
Other notable findings in the investigation include:
- Nearly two thirds of service members in this sample had reactive antibodies.
44 (18.5 percent) of service members who were identified as having a current or previous SARS-CoV-2 infection did not report any symptoms.
- Among those who provided nasal swabs, just over one third tested positive for current infection.
- Loss of taste or smell was the symptom most associated with current or previous infection; participants reporting these symptoms were 10 times more likely to have infection than were those who did not.
- Among 12 participants with antibodies that were detected longer than 40 days after symptom onset, eight remained neutralization positive including two participants who were tested 3 months after symptom onset.
- Among all participants, current or previous infection was more common among males than females, but did not differ significantly by age, race, ethnicity, or history of a pre-existing medical condition.
- Current or previous infection was higher among participants who reported contact with someone known to have COVID-19 (64.2 percent) compared with those who did not (41.7 percent) and higher among service members who reported sharing a room with another service member that tested positive (65.6 percent) compared with those who did not.
- Service members who reported taking preventive measures compared to those who did not had a lower infection rate (wearing a face covering (55.8 percent versus 80.8 percent), avoiding common areas (53.8 percent versus 67.5 percent), and observing social distancing (54.7 percent versus 70.0 percent).
This study is in line with the cruise ships that had undetected transmission of the Corona Virus due to the mild and asymptomatic nature of the infection. The virus spreads easily between people living in close quarters.
Young, healthy adults with the virus may have mild, atypical or no symptoms at all, so symptom-based surveillance may not detect the infection. Using face coverings and taking other preventative measures can mitigate the transmission. The neutralizing antibodies among the majority of participants in this study is promising of at least short-term immunity.
The Corona Virus impacted the crew of the Roosevelt harder than any other military unit. The Navy is committed to making the best decisions it can to protect the health and safety of its Sailors.
The outbreak investigation provides an opportunity to make a difference in helping the nation battle the virus and containing future outbreaks.
“This is a stealthy virus and the results from this outbreak investigation provides us with increased knowledge about COVID-19 so we can better protect the crew, their shipmates on other vessels, and ultimately the nation,” said Rear Adm. Bruce Gillingham, US Navy Surgeon General.
The findings in the outbreak investigation on the Roosevelt and information from the outbreak on the USS Kidd is helping the Navy navigate to what a “new normal” looks like aboard their vessels. It is important to sustain underway operations during future outbreaks when a ship may not be able to pull into port or medically evacuate personnel due to geographic or operations concerns.
On May 27 the Navy issued new Standard Operational Guidance providing direction for isolation, quarantine and contact tracing upon any future outbreaks of the Corona Virus.
Lessons learned from the TR include the value of using and enforcing strict ship-board protocols to contain the spread of the virus. Preventative and mitigation efforts have shown to be effective. Several ships have had positive cases of the Corona Virus. Quick actions of the crew have contained the virus to a small group allowing the ships to continue their planned operations.
“Protecting the total workforce remains our top priority. At the same time the Navy is still answering the call to defend the nation, protect sea lanes, and assist those in need. The Navy will continue to operate in this ‘new normal’ environment with COVID, but won’t be limited in our ability to respond to whatever our Nation needs,” said Vice Admiral Phillip Sawyer, the Navy’s operations chief in charge of coordinating the service’s response to the Corona Virus.