OUTBREAK OF NOROVIRUS GASTROENTERITIS IN ELDERLY EVACUEES AFTER THE 2007 NOTO PENINSULA EARTHQUAKE IN JAPAN

Communicable Diseases After the Disasters: with the Special Reference to the Great East Japan Earthquake

On March 11, 2011, the Great East Japan Earthquake – a massive temblor followed by a gigantic tsunami was associated with significant morbidity and mortality. Among many health problems such as trauma, drowning, and mental illnesses, infectious diseases may place significant burden on survivors of such disasters. Wound infections including tetanus, leptospirosis, legionellosis, rickettsiosis, respiratory infections, and diarrheal illness among other infections had been considered to be associated with earthquake and tsunami. Overall, the impact of infectious diseases after the Great East Japan Earthquake was relatively small, with only sporadic outbreaks observed. The incidence of serious infections such as tetanus, legionellosis, and tsunami lung, was also low, considering the overall impact of the earthquake and tsunamiper se. This review discusses the impact of infectious diseases after the Great East Japan Earthquake, and reviews past disaster-related infections as reference.

Investigation of norovirus occurrence in groundwater in metropolitan Seoul, Korea

Groundwater is an important source of drinking and household water worldwide. Hence, the quality of groundwater is very important for preventing waterborne disease outbreaks and should be properly monitored. This study investigated the prevalence of waterborne viruses and fecal indicators in groundwater in metropolitan Seoul and Gyeonggi province, South Korea. A total of 116 samples of groundwater were taken using NanoCeram filters during both summer (June to August) and fall-winter seasons (October to December) in 2008. Among 71 sampling sites, 28 (48.3%) and 18 (35.3%) were positive for norovirus (NoV) from the summer and fall-winter season, respectively. The identified genotypes of NoV include GI-1, 4, 8, 9 and GII-4, 10, 11 (or 17), 13, 15 (or 16). None of fecal indicators was significantly correlated with NoV in groundwater. Among the tested fecal indicators, somatic coliphage (95.3%) showed an excellent true-negative rate of NoV occurrence. The combination of chemical, microbial and viral indicators increased the positive predictive value (50-100%). This study demonstrated a high prevalence of NoV in groundwater in metropolitan Seoul areas and characterized the positive and negative predictive values of a fecal indicator for predicting NoV prevalence.

Norovirus as a foodborne disease hazard

Norovirus (NoV) is the most common cause of infectious gastroenteritis in the world. Gastroenteritis caused by bacterial and parasitic pathogens is commonly linked to food sources, but the link between NoV and contaminated foods has been more difficult to establish. Even when epidemiological information indicates that an outbreak originated with food, the presence of NoV in the suspect product may not be confirmed. If food is found to contain a common strain of NoV that circulates widely in the community, it is not possible to use strain typing to link the contamination to patient cases. Although food is certainly implicated in NoV spread, there are additional person-to-person and fomite transmission routes that have been shown to be important. NoV has an extremely low infectious dose, is stable in the environment, and resists disinfection. Cell culture methods are not available, so viability cannot be determined. Finally, many NoV outbreaks originate with when an infected food handler contaminates ready-to-eat food, which can be interpreted as foodborne or person-to-person transmission. This review will discuss both the physical characteristics of NoVs and the available epidemiological information with particular reference to the role of foods in NoV transmission.

Infectious diseases following disasters

Infectious diseases following natural disasters tend to occur as a result of the prolonged secondary effects of the disaster, mostly when there is an interruption of public health measures resulting from destruction of the local infrastructure. This article will review the infectious risks that occur as a result of natural disasters, with a focus on the mechanism of disease spread, infectious diseases after specific disasters, and various evidence-based interventions.