Report on “Radiation Disaster Recovery Studies”
Course:Name:Radiation Disaster Medicine
CHUON CHANNARENA○ Regarding “Radiation Disaster Recovery Studies”（Describe your thoughts, the process you engaged in and your research progress regarding Recovery from
Radiation Disaster.）Yields of the 4 years that I learned in the differences of multidisciplinary on the health-related

radiation effects from academic activities, scientific papers and technical reports through the history ofnuclear accidents. In Japan, 1945, the first nuclear weapons related tragedy of human history wasreported during wartime after the atomic bombs dropped on the cities of Hiroshima and Nagasaki, morethan 200,000 people lost their lives due to blast, heat and high radiation dose from atomic bombs.[1] The
Atomic Bomb Casualty Commission (ABCC: 1947-1975) was established two years later after bombings

with the aim to investigate the radio-epidemiological studies on the impact of radioactivity from atomicbombings among survivors. The three major studies had been conducted; one focused on mortality andcancer incidence among A-bomb survivors called Life Span Study (LSS), another one was in utero cohort

study and last one was the investigation of radiation-related health effects among their children so called
F1 study.[2] Since 1975 to date, the ABCC was renamed the Radiation Effects Research Foundation (RERF)

in order to extend the investigations and to increase the capacity of the follow-up in the cohort studies

and F1 studies. According to many publications and technical reports of the epidemiological studies onLSS, in utero cohort and F1 studies from the ABCC-RERF, the risks of cancer and other diseases fromexposure to ionizing radiation were estimated as primarily basis and then the estimation was used forthe national and international standardization for radiation-related health effects. However, it defines as
global standardization of health risk due to radiation exposure, but various health outcomes such as
cancers and non-cancer diseases caused by the stochastic effects is not well-known because of lack of
information about the basic data on health effects during the first 5 years after bombings.[1, 3-5]

Following the Great East Japan Earthquake on March 11th, 2011, residents who lived near to the Nuclear

Daiichi Power Plant were forced to evacuate from their hometown whilst the ionizing radiation emitted
to the atmosphere from the explosion of nuclear reactor. In order to response to nuclear hazards inFukushima areas, the Fukushima prefecture governor has established Fukushima Health Management
Survey (FHMS) and cohort epidemiological studies were also established immediately to date.[6]In addition, I have learned many special lectures from domestic and international experts from RERF,

IAEA, ICRP, Japan-Red-Cross and so on, which organized by the Phoenix Leader Education Program,

Hiroshima University. As well as, many activities such as long-term fieldwork at Fukushima Nuclear
Daiichi Power Plant (NPP), visited residents who lived in temporary housings, learn how to monitor theexternal and internal radiation exposure result from radioactive materials from NPP at Minamisoma
Municipal General hospital and to monitoring the radioactive materials emitted to the soil, air, water andground in affected area and so on. Notably, I could have a chance to do internship at the RERF,

department of epidemiology which trained me to understand the importance of accumulating data ofA-bomb survivors and general population for the reference at the ordinary time. The department ofepidemiology at the RERF is an important department for RERF to estimate the risk of mortality andcancer incidence of A-bomb survivors regarding the effects of radiation exposure. Beyond the leading

program, I also belong to the department of epidemiology, infectious disease, control and prevention ofHiroshima University. I have learned about the public health and health promotion policy. Furthermore, I
have participated and made oral and poster presentations on the progression of my research in the fieldof public health and epidemiology in Japan and internationally.

Within the 4 years, I have learned knowledge about radiation-related health effects and radiation

epidemiology through the Phoenix Leader Education Program, the department of epidemiology in

Hiroshima University and RERF. It has made me think of the current situations of Cambodia and the factof nuclear power plants will be introduced in Cambodia in the near future. Then, I have figured out that anational health check-ups system has not yet established to schoolchildren and general population inCambodia, therefore building such as medical examination system will be an important foundation for

knowing the health hazard in emergency such as radiation disasters and warfare. In Cambodia, in casedisaster may occur in the future and lack of national health basic data before disaster, so it is difficult tounderstand the range impact of health-related disaster after disasters. Based on that, it is necessary toaccumulate health data among school children and general population in Cambodia as well as set it for

the reference as a nationally representative. In my doctoral study, I started to conduct a pilot study forthe health check-ups system at elementary school in Cambodia. This research emphasized on the healthcheck-up promotion to Cambodia and as the result of this pilot study which could be provided a basis

database for reference the current health condition of school children in ordinary time of Cambodia.
References

1. Kamiya, K., et al.:Long-term effects of radiation exposure on health. Lancet,386(9992):469-478,2015.
2. Radiation Effects Research Foundation. 2014 - 2015 Annual Report of the Radiation Effects ResearchFoundation, 2015.

Retrieved from: https://www.rerf.or.jp/en/library/list-e/periodicals/annualreport_e/2014-e/

3. Ozasa, K., et al.:Association of Acute Radiation Syndrome and Rain after the Bombings in Atomic BombSurvivors. Radiat Res,185(6):604-615,2016.

4. Sakata, R., E.J. Grant, and K. Ozasa et al.:Long-term follow-up of atomic bomb survivors. Maturitas, 72(2):99-103,2012.

5. Grant, E.J., et al.:Solid Cancer Incidence among the Life Span Study of Atomic Bomb Survivors: 1958-2009.

Radiat Res,187(5):513-537,2017.

6. Yasumura, S., et al.:Study protocol for the Fukushima Health Management Survey. J Epidemiol,22(5):375383,2012.

○ Title of Doctoral Thesis
Title: The pilot study for health check-ups system at elementary school in Cambodia(カンボジア王国における小学生を対象とする健康診断システム構築に関するパイロット調査)○ Summary of Doctoral Thesis（Describe so as to be easily understood, by relating it to“Radiation Disaster Recovery Studies”.）[Introduction and Aims]
Schools are well-known as places for providing education to all people. The World HealthOrganization (WHO) has added more roles to the schools for the health promotion programme to theschool children. In 1995, health check-up was introduced in the schools under the frameworks for Health

Promotion in School (HPS) by WHO. Establishment of health check-ups system at elementary schools
could contribute not only for the health and welfare of children but also accumulating national healthbasic data in ordinary time.

In Japan, primary school health examination has been introduced since the Meiji era, and their basic

data functions as a basis for evaluating health problems caused by atomic bomb damage in Hiroshimaand Nagasaki and nuclear damage in Fukushima. In Cambodia as well, based on the fact that nuclear

power plants will be introduced in the future, building such a medical examination system will be an
important foundation for knowing the health hazards in emergency such as radiation disasters andwarfare. However, in Cambodia, a national health check-ups system has not been established yet toschoolchildren and general population. This is the pilot study on school health check-ups in cooperation
with the government of Cambodia aimed to promote health check-ups system in Cambodia.

[Materials & Methods]
This study was conducted at Teacher Training elementary school in Siem Reap province, Cambodia inJune 2016 and August 2017. The subjects were all students at graders 3 and 4 (academic year 2016), 3and 6 (academic year 2017) at the elementary school. Totally, 349 students were asked to participate inthis study and 294 of them agreed after written consent of parents. Except for 2 students whose data
were missed, totally 292 students, 135 in 2016 and 157 in the 2017, were analyzed.

This study contains questionnaires, physical examination for ENT, lung and heart as well as urinalysis,using Japanese school health check-ups model. We used the WHO guideline of growth reference, in which
the growth chart was classified by Standard Deviation (SD) of BMI value. The reference value of SD is set

different depending on month old and is classified as Overweight: >+1SD, Obesity: >+2SD, Thinness:<-2SD, and Severe thinness: <-3SD. The questionnaire included major 16 items such as current and pasthealth status, subjective symptoms, vaccination history, which was answered by parents. We diagnosed

the results based on the evaluation criteria which was set by using the result of the questionnaire and/or
physical examinations. For the students suspected of unhealthy, face-to-face interview was conducted in2016, but in 2017, a recommendation letter was given without interviews. This study was approved by
the Ethics Committee in Ministry of Health, Cambodia (Permission No. 0085 NECHR) and Hiroshima
University, Japan (Permission No. E-224-1).

[Results]
Totally 292 students (mean age: 9.8+1.7 years, 54.5% boys and 45.5% girls) were eligible for data

analysis. The overweight and underweight prevalence was 15.1% and 8.6%, respectively. In the results of

the questionnaire, dental caries (62.3%), weight stunt (24.7%), history of sudden tachycardia (6.2%),
history of arrhythmia (2.1%), syncope during exercise (1.0%), chest pain during exercise (4.5%),

dyspnea on exertion (14.0%) and dyspnea during walking (8.6%) were observed. The vaccination
coverage was 50.0% (Diphtheria), 47.3% (Pertussis), 60.6% (Tetanus), 62.0%(BCG), 41.8% (Hepatitis B),

66.4% (Polio) and 79.8% (Measles). In physical examination, 20 (6.9%) students were suspected of otitis
media by otoscopy but none of them had hearing deficits. Two (0.7%) students had hypertrophy tonsillar

grading 3 and 2 (0.7%) students had rale. Urinalysis results showed that 7 (2.4%) students had
proteinuria 1+ and 1 (0.3%) student had hematuria 2+ with proteinuria 1+.

Based on the evaluation criteria of this study, 38 (13.0%) students (10 in 2016 and 28 in 2017) weresuspected of having health problem. In 2016, among the 10 students, 7 of their parents were answeredthat their children had cardiopulmonary symptoms, but we did not find abnormality in physicalexamination and after interview we diagnosed four of them as healthy. We also diagnosed as healthy for
one student with tonsillar hypertrophy after interview. However, one with rale was advised to continue

follow-up at hospital and another was recommended for further examination at hospital because ofabnormal urinalysis.

In 2017, 28 (9.6%) students were diagnosed as unhealthy. Among them, 27 (9.2%) had cardiopulmonary
symptoms without any physical findings. Another one had rale with high fever. All the 28 students
received a recommendation letter for further check at hospital.

Considering the results of the interview in 2016, totally 88.7% (259/292) students were diagnosed

as healthy in this study.

[Discussion]
In this study we revealed that 88.7% of the schoolchildren diagnosed as healthy. This result could be

one of basis data for the current health condition of children in ordinary time of Cambodia. On the otherhand, we found students with health problem, such as cardiopulmonary subjective symptoms, abnormal
urinalysis, rale sound and recommended them for further check at a hospital. These results suggest thatthe health check-ups was performed effectively as a 1st screening.

Contrary to previous reports, the prevalence of overweight (15.1%) was more than underweight(8.6%) in this study. These results suggested that possibility of change of nutritional status, life-style inhome, the activity of school time or other factors among elementary school children in Cambodia, but

selection bias should be considered because this study conducted only in a public school in urban area.
To promote physical activity and healthy eating in order to prevent obesity or lifestyle-related diseases
will become necessary to the future children in Cambodia.

The parents-report vaccination coverage was as low as 41.8% for hepatitis B virus (HBV), although

Cambodia is highly endemic area for HBV infection with high hepatocellular carcinoma mortality rate.
Elementary school is supposed to be the most optimal institution to grasp the health condition of thewhole pediatric population where assessment for the vaccination can be done. From this assessment on
HBsAb, it will be useful for catch-up vaccination of HBV to school children with lack of antibody.

[Conclusion]
In this pilot study, we showed the prevalence of healthy among schoolchildren of Cambodia anddetected the students with possibility of health problem through this screening and recommended forvisit hospital. Base on the results, we assume that health check-ups system in elementary school innationwide will be effective reference to the health surveillance in ordinary time in Cambodia.

○ Other theses and sub-dissertation published in academic research journals

1. Hiroko Yamada, Kazuaki Takahashi, Olline Lim, Somana Svay, Channarena Chuon, Sirany Hok, Son
Huy Do, Mayumi Fujimoto, Tomoyuki Akita, Noboru Goto, Keiko Katayama, Masahiro Arai, and JunkoTanaka : Hepatitis E Virus in Cambodia: Prevalence among the General Population and Complete
Genome Sequence of Genotype 4. PLoS One,10(8):e0136903,2015. (Impact factor: 3.54, peer-review)

2. Terumi Kaishima, Toshiko Fujii, Toshihiko Matsuoka, Kazuki Sakamune, Shintaro Nagashima,
Chikako Yamamoto, Channarena Chuon, Mami Yamashita, Masayo Yamato, Hiroko Fuji, Basilua

Andre Muzembo, Aya Sugiyama, Masayuki Ohisa, Tomoyuki Akita, Keiko Katayama, Junko Tanaka :Study of the issues of receiving hepatitis screening and the rate of consulting hospital -The rate ofrecognized receiving hepatitis screening and that of the unrecognized-. Kanzo,57:634-648,2016.
(peer-review)

3. Junko Matsuo, Son Huy Do, Chikako Yamamoto, Shintaro Nagashima, Channarena Chuon, KeikoKatayama, Kazuaki Takahashi, and Junko Tanaka : Clustering infection of hepatitis B virus genotype
B4 among residents in Vietnam, and its genomic characters both intra- and extra-family. PLoS

One,12(7):e0177248,2017. (Impact factor: 3.54, peer-review)

4. Aya Sugiyama, Masayuki Ohisa, Shintaro Nagashima, Chikako Yamamoto, Channarena Chuon,
Toshiko Fujii, Tomoyuki Akita, Keiko Katayama, Yoshiki Kudo, Junko Tanaka : Reduced prevalence ofhepatitis B surface antigen positivity among pregnant women born after the national

implementation of immunoprophylaxis for babies born to hepatitis B virus‐carrier mothers in Japan.
Hepatology Research,47(12):1329-1334,2017. (Impact factor: 1.94, peer-review)5. Mayumi Fujimoto, Channarena Chuon, Shintaro Nagashima, Chikako Yamamoto, Ko Ko, SomanaSvay, Sirany Hok, Olline Lim, Masayuki Ohisa, Tomoyuki Akita, Keiko Katayama, Junko Matsuo,Kazuaki Takahashi, Junko Tanaka : A seroepidemiological survey of the effect of hepatitis B vaccine

and hepatitis B and C virus infections among elementary school students in Siem Reap province,Cambodia. Hepatology Research,48(3):E172-E182,2018. (Impact factor: 1.94, peer-review)

6. Aya Sugiyama, Toshiko Fujii, Shintaro Nagashima, Masayuki Ohisa, Chikako Yamamoto, Channarena
Chuon, Tomoyuki Akita, Junko Matsuo, Keiko Katayama, Kazuaki Takahashi, Junko Tanaka : Pilot
study for hepatitis virus screening among employees as an effective approach to encourage
employees

whoscreened

positivetoreceive

medicalResearch,48(3):E291-E302,2018. (Impact factor: 1.94, peer-review)careinJapan.

Hepatology