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Japan is one of the countries conducting longitudinal serosurveillance of vaccine-preventable diseases. We conducted surveillance of the local measles-specific antibody titer, calculated the effective reproduction number (R e ), and compared data of four terms: term 1, 2003-2006 (before the introduction of the second shot of measles-containing vaccine); term 2, 2007-2010 (early term toward measles elimination); term 3, 2011-2014 (later term toward measles elimination); and term 4, 2015-2020 (after elimination of measles in Japan). Approximately 250 sera from volunteers aged 0 to ≥ 40 years were collected and examined for measles-specific IgG using the gelatin particle agglutination (PA) method annually from 2003 to 2020. Seroprevalence and the geometric mean of the PA antibody titer were examined by term. R e was calculated using the age-dependent proportion immune and contact matrix for each term. Of the 4,716 sera, 886 in term 1, 1,217 in term 2, 1,069 in term 3, and 1,544 in term 4 were collected. The seroprevalence gradually increased from term 1 (88.3% CI 86.0-90.3) to term 4 (95.7% CI 94.6-96.7), and the seroprevalence of term 1 was significantly lower than those of other terms (Fisher's exact test, p < 0.001), with PA titer ≥ 16 as positive. By contrast, PA antibody titers significantly decreased from term 1 (median 1,024) to term 4 (median 256) (Mann-Whitney U test, p < 0.001). With the protection level (PA titer ≥ 128 and ≥ 256) as positive, R e gradually increased from term 1 (1.8 and 2.3) to term 4 (2.5 and 4.8, respectively). Waning levels of measles antibodies potentially increase the measles susceptibility in Osaka, Japan. This trend might imply a limitation of vaccine-induced immunity in the absence of a natural booster for wild strains after measles elimination. This study provides a cue for maintaining continuous measles elimination status in the future., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Severe fever with thrombocytopenia syndrome (SFTS) is a novel tick-borne infectious disease, therefore, the information on the whole genome of the SFTS virus (SFTSV) is still limited. This study demonstrates a nearly whole genome of the SFTSV identified in Osaka in 2017 and 2018 by next-generation sequencing (NGS). The evolutionary lineage of two genotypes, C5 and J1, was identified in Osaka. The first case in Osaka belongs to suspect reassortment (L:C5, M:C5, S:C4), the other is genotype J1 (L: J1, M: J1, S: J1) according to the classification by a Japanese group. C5 was identified in China, indicating that C5 identified in this study may be transmitted by birds between China and Japan. This study revealed that different SFTSV genotypes were distributed in two local areas, suggesting the separate or focal transmission patterns in Osaka.

An epidemiological survey focused on farmers engaged in vinyl-house culture of strawberry was carried out among the inhabitants of a farming village. For avoiding residential and habitual factors, all residents (851 in number) over 12 years of age in the area were inquired about symptoms, personal and family histories. There were no marked difference in age and sex among three groups, i.e. farmers with and without vinyl-house culture and people with no relation to farming in this area. Incidence of one of the inquired symptoms were 54% and 45% in farmers with and without strawberry culture in vinyl-house respectively, and 34% in the non-farming people. This difference became more larger up to 83% in the strawberry farmers of allergic constitution. Symptoms found more in the farmers than the other were headache, dizziness, conjunctivitis, rhinorrea, sneeze, palpitation and neuralgia, and the last four symptoms were more marked among farmers in charge of strawberry culture. Incidence of the allergic symptom consisting of conjunctivitis, rhinorrea and sneeze was more marked among the persons of allergic constitution . In conclusion, health effects of strawberry culture in vinyl-house in farmers can be look upon from three aspects; overwork, a particular stance during the work and allergic responses to the dust in the vinyl-house.

Prevalence studies of Japanese cedar pollinosis in densely planted areas were performed using pollen counts, patient studies, and population surveys with questionnaires. The incidence of pollinosis was increased and appeared to be related to dispersed pollen, which resulted in high immunologic responses. Onset of symptoms was influenced by hereditary factors as well as pollution from automobile exhausts.

Clinical mass surveys were carried out on the residents to whom questionnaires on symptoms with reference to strawberry culture in the vinyl-house had been delivered. Two hundred and eleven persons attended at the first survey in September, 1976 (off the season of strawberry culture) and the 58 attended at the second survey in March, 1977 (within the season). The participants of the first survey consisted of three groups, i.e. farmers with and without strawberry culture and people without farming. The participants of the second survey consisted only of farmers with strawberry culture. Results are summarized as follows. 1) There were no difference of incidence of various clinical findings detected by an ophthalmologist and otolaryngologists among the three groups. 2) There were also no difference of incidence of abnormal findings in urine tests, liver functions, respiratory test, blood examinations and blood pressure test among the three groups. However, the comparison of persons in charge of strawberry culture and attended at both tof the first and the second surveys, such changes were detected as increases in the value of GOT (within normal limits), of stab neutrophiles, lymphocytes and of monocytes within the season of strawberry culture. 3) Increases of positive rates in skintest by extracts of house dust and Candida sp. were observed in the farmers with and without strawberry culture. Positive rates of skintest by strawberry pollen and honey bee extracts among the farmers with strawberry culture were markedly higher than the allergic patients in Dokkyo Hospital having no relation to this culture. This positive rate was markedly elevated among the persons who complained the symptom of rhinorrea within the season.