Lack of cross-transmission of SARS-CoV-2 between passenger's cabins on the Diamond Princess cruise ship

Area of Science:

• Epidemiology
• Infectious Diseases
• Public Health

Background:

• The Diamond Princess cruise ship experienced a significant COVID-19 outbreak in early 2020.
• Understanding transmission routes is crucial for controlling infectious disease spread in confined environments.

Purpose of the Study:

• To investigate the potential for airborne transmission of SARS-CoV-2 between cabins on the Diamond Princess cruise ship.
• To identify the primary transmission pathways of COVID-19 during the shipboard outbreak.

Main Methods:

• Analysis of infection case data from the Diamond Princess cruise ship outbreak.
• Inference of transmission timelines and spatial distribution of cases.
• Evaluation of the roles of the ship's ventilation and drainage systems.

Main Results:

• No evidence of airborne SARS-CoV-2 transmission between ship cabins was found.
• The ship's central air-conditioning and drainage systems were not implicated in inter-cabin transmission.
• Infections primarily occurred in public areas, suggesting transmission linked to crowding and inadequate ventilation.

Conclusions:

• Sufficient ventilation in passenger cabins likely prevented airborne transmission between them.
• Public areas of the cruise ship were the main sites for COVID-19 transmission.
• Enhanced ventilation and crowd management are critical in similar settings to prevent outbreaks.