Zika fever, a mosquito-borne infectious disease caused by Zika virus (ZIKV), is an epidemic disease for which no effective therapy has been established. The recent outbreaks of ZIKV in Brazil and French Polynesia have been linked to a considerable increase in the incidence of fetal microcephaly and other diseases such as Guillain-Barre syndrome. Because there is currently no specific therapy or vaccine, the early exploitation of a method to prevent expansion of ZIKV is a high priority. To validate commonly used antiviral drugs, we evaluated the effect of ribavirin, a drug used to treat hepatitis C with interferon-β (IFN-β), on ZIKV replication. In mammalian cells, we observed an inhibitory effect of ribavirin on ZIKV replication and ZIKV-induced cell death without cytotoxic effect. Furthermore, we found that STAT1-deficient mice, which lack type I IFN signaling, were highly sensitive to ZIKV infection and exhibited lethal outcome. Ribavirin abrogated viremia in ZIKV-infected STAT-1-deficient mice. These data suggest that the inhibition of viral RNA-dependent RNA polymerases may be effective for treatment of ZIKV infection. Our data provide a new insight into the mechanisms for inhibition of ZIKV replication and prevention of Zika fever.

No abstract

Chikungunya fever is a mosquito‐borne disease cause of persistent arthralgia. The current diagnosis of Chikungunya virus (CHIKV) relies on a conventional reverse transcription polymerase chain reaction assay. Reverse transcription loop‐mediated isothermal amplification (RT‐LAMP) is a rapid and simple tool used for DNA‐based diagnosis of a variety of infectious diseases. In this study, we established an RT‐LAMP system to recognize CHIKV by targeting the envelope protein 1 (E1) gene that could also detect CHIKV at a concentration of 8 PFU without incorrectly detecting other mosquito‐borne viruses. The system also amplified the E1 genome in the serum of CHIKV‐infected mice with high sensitivity and specificity. Moreover, we established a dry RT‐LAMP system that can be transported without a cold chain, which detected the virus genome in CHIKV‐infected patient samples with high accuracy. Thus, the dry RT‐LAMP system has great potential to be applied as a novel CHIKV screening kit in endemic areas.

No abstract

People who have dementia with Lewy bodies often have sleep disorders. We used non-wearable devices to record and categorize the sleep patterns of patients with Lewy body dementia. Individual sleep data at a dementia–care unit in Japan were recorded using non-wearables. One week’s worth of data from 18 patients was analyzed. Median metrics for all participants were the following: sleep efficiency, 68% (23-89); sleep duration at night, 6.8 hours (1.6-11.1); times getting out of bed at night, 3.5 (0-13). We identified three types of abnormal sleep: extremely short sleep duration, excessive sleep duration at night, and excessive number of times getting out of bed at night. Sleep disturbances in Lewy body dementia patients are treated using various practices; staff must choose the most effective plan for each patient’s situation. Monitoring patient sleep using non-wearable provides more objective data that can help staff better personalize nursing care.