Increased pneumonia rates after Tohoku earthquake
medwireNews: Significantly increased rates of pneumonia and related deaths were seen after the 2011 Earthquake and Tsunami in Tohoku, Japan, report researchers.
"Although the exact cause remains unresolved, multiple factors including population aging and stressful living conditions likely contributed to this pneumonia outbreak," say Motoi Suzuki (Nagasaki University, Sakamoto, Japan) and co-authors of the study published in Thorax.
The investigators assessed the incidence of adult community-acquired pneumonia and related mortality in three hospitals in Kesennuma City between March 2010 and June 2011.
Over this period there were 550 pneumonia-related hospitalizations, 325 of which occurred before the disaster on 11th March 2011 and 225 after the disaster. The mean weekly incidence of pneumonia hospitalizations and deaths increased dramatically by a significant 5.7- and 8.9-fold in the 3-month period after the disaster occurred, although the highest increase was in the 2 weeks after the event and rates gradually dropped to normal levels by the middle of June 2011.
In previous similar natural disaster zones an increase in severe pneumonia associated with inhalation of seawater known as "tsunami lung" has been observed. However, in this case only 3.6% of the patients admitted with pneumonia after the Tohoku Earthquake and Tsunami had experienced near-drowning in the tsunami waters.
The large majority (nearly 90%) of patients admitted after the disaster were older adults aged 65 years or above who lived in nursing homes. Just under a third (27.7%) were living in evacuation shelters when admitted to hospital, although these patients were younger (76.7 vs 80.0 years), were less likely to have comorbidities (45.0 vs 59.9%), and were less likely to have fatal pneumonia (10.0 vs 29.3%) than patients who were living in residences and nursing homes when admitted.
"Because this disaster affected a notably aging population with the highest baseline pneumonia incidence rate, the disaster caused a drastic increase in the number of admissions and placed a heavy burden on local hospitals," write Suzuki and team.
"In addition to using the pneumococcal vaccine for disaster-affected populations, the provision of optimal living conditions, medical check-ups and oral hygiene care must be a priority for older people after natural disasters."
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By Helen Albert, Senior medwireNews Reporter