@bug_in je me suis fait la même remarque.
D’autant plus, qu’en suivant ces sites militants, on constate que les chiffres sont parfois recopiés un peu rapidement. Ainsi, sur le site (sans doute) original, on trouve bien les 48% mentionnés, mais les effectifs sont sensiblement différents.
Fukushima children thyroid cancer cases spreading to their lymph nodes and lungs | Evacuate Fukushima
▻http://evacuatefukushimanow.wordpress.com/2014/06/12/福島県の甲状腺がん-fukushima-children-thyroid-cancer-cases-sp
370,000 children under 18 at the time of the nuclear accident are subject to thyroid examination and so far, 50 have been confirmed to have cancer and 39 are suspected.
90 cases in total – When you hear “90 cases or suspected cancers”, don’t bother. 98% of the “suspected” cases turned out to be CONFIRMED last time around. So, not be insensitive, it is 90 cases confirmed .
51 had surgeries as of March 31, 2014
Total number of children whose initial examination results are confirmed: 287,056
Assessment
A1 = 148,182 (51.6%) (no nodules or cysts found)
A2 = 136,804 (47.7%) (nodules 5.0 mm or smaller or cysts 20.0 mm or smaller)
B = 2,069 (0.7%) (nodules 5.1 mm or larger or cysts 20.1 mm or larger)
C = 1 (0.0%) (requiring immediate secondary examination)
J’ai cherché des prévalences en population générale, mais c’est difficilement comparable. Le taux augmente sensiblement avec l’âge.
Pour les taux de cancer de la thyroïde, les chiffres présentés donnent environ 90 cancers sur 300 000 enfants, soit 150 par million (sur 3 ans, ce qui n’est pas précisé).
Si on compare avec le graphique fourni sur un autre billet du même blog
▻http://evacuatefukushimanow.wordpress.com/2014/02/08/breaking-news-75-children-have-now-being-diagnosed-w、こどもの甲状腺がん75/
on est assez loin des « 40 fois plus élevé ».
Les Hôpitaux Universitaires de Genève donnent aussi des éléments de comparaison (de l’ordre de 25 nouveaux cas par an et par million, en population générale).
▻http://www.hug-ge.ch/sites/interhug/files/atelier_mpr/080416_nodule_thyroidien.pdf
Enfin, on trouve une référence solide sur la procédure de dépistage, ses résultats et des éléments de comparaison dans le rapport 2013 du Comité scientifique des Nations Unies sur l’Effet des Radiations Atomiques (UNSCEAR) publié le 2 avril 2014.
▻http://www.unscear.org/docs/reports/2013/13-85418_Report_2013_Annex_A.pdf (p. 79, §180)
180. Thyroid ultrasound examinations were to be made for all individuals in Fukushima Prefecture who were aged 18 years or younger on 11 March 2011 (about 360,000) and were expected to be completed within 3 years (by March 2014). Thereafter, children would undergo thyroid examinations every 2 years until age 20 and every 5 years thereafter [Y5]. By the end of July 2013, about 175,000 children living in Fukushima Prefecture had received thyroid examinations using modern, highly sensitive ultrasound equipment [F3]. Thyroid nodules had been detected in about 1% of those surveyed and thyroid cysts in about 40% of those surveyed. A survey, using similar equipment, of about 4,000 children and adolescents had also been made in the prefectures of Aomori, Yamanashi and Nagasaki [T5] which were largely unaffected by the accident; the observed incidence of thyroid nodules and cysts there was even larger than that observed in Fukushima Prefecture. This indicates that the high detection rate of nodules and cysts in all of these surveys is a consequence of the intensive screening and the highly sensitive nature of the equipment being used, and not of additional radiation exposure resulting from the accident.
