Impact of school closure due to the coronavirus disease 2019 pandemic on body mass index in Japanese children: Retrospective longitudinal study.

Aim: During the coronavirus disease 2019 pandemic, the governments of many countries responded to high levels of infection with lockdowns. As a result, some children were reported to experience weight gain. The aim of the present study was to examine the impact of school closures on body mass index (BMI) in Japanese children.

Changes in epidemiological characteristics and sero-prevalence against the varicella zoster virus in school-age children after the introduction of a national immunization program in Japan.

A national immunization program using two doses of live attenuated varicella vaccine was introduced for children aged one to two years in Japan in October 2014. Varicella cases declined after 2014, and immunological status against varicella among vaccinated children changed in post-vaccination era. A retrospective observational study of anti-varicella antibody seroprevalence, varicella vaccination status, and history of varicella among 528 students in the first grade of elementary school was conducted.

Simultaneous Administration of Recombinant Measles Viruses Expressing Respiratory Syncytial Virus Fusion (F) and Nucleo (N) Proteins Induced Humoral and Cellular Immune Responses in Cotton Rats.

We previously reported that recombinant measles virus expressing the respiratory syncytial virus (RSV) fusion protein (F), MVAIK/RSV/F, induced neutralizing antibodies against RSV, and those expressing RSV-NP (MVAIK/RSV/NP) and M2-1 (MVAIK/RSV/M2-1) induced RSV-specific CD8⁺/IFN-γ⁺ cells, but not neutralizing antibodies. In the present study, MVAIK/RSV/F and MVAIK/RSV/NP were simultaneously administered to cotton rats and immune responses and protective effects were compared with MVAIK/RSV/F alone. Sufficient neutralizing antibodies against RSV and RSV-specific CD8⁺/IFN-γ⁺ cells were observed after re-immunization with simultaneous administration.

School-age children and adolescents suspected of having been to be infected with pertussis in Japan.

Many countries including Japan have adapted acellular pertussis vaccines combined with diphtheria and tetanus toxoids (DTaP). DTaP vaccine coverage is approximately >90%, but pertussis re-emergence has been observed since 2000 in Japan. In the present study, anti-pertussis antibodies were investigated among school-age children and adolescents from 2013 to 2015.

Development of Acquired Immunity following Repeated Respiratory Syncytial Virus Infections in Cotton Rats.

Respiratory syncytial virus (RSV) infections occur every year worldwide. Most infants are infected with RSV by one year of age and are reinfected because immune responses after the first infection are too weak to protect against subsequent infections. In the present study, immune responses against RSV were investigated in order to obtain a better understanding of repetitive RSV infections in cotton rats.

Cell fusion assay by expression of respiratory syncytial virus (RSV) fusion protein to analyze the mutation of palivizumab-resistant strains.

Respiratory syncytial virus (RSV) consists of fusion (F), glyco (G), and small hydrophobic (SH) proteins as envelope proteins, and infects through cell fusion. F protein is expressed on the surface of infected cells, and induces cell fusion. In the present report, expression plasmids of the F, G and SH proteins were constructed and cell fusion activity was investigated under T7 RNA polymerase.