Evaluation of modelling study shows limits of COVID-19 importing risk simulations in sub-Saharan Africa.

Mathematical modelling studies predicting the spread of the coronavirus disease 2019 (COVID-19) have been used worldwide, but precisions are limited. Thus, continuous evaluation of the modelling studies is crucial. We investigated situations of virus importation in sub-Saharan Africa (SSA) to assess effectiveness of a modelling study by Haider N et al. titled 'Passengers' destinations from China: low risk of novel coronavirus (2019-nCoV) transmission into Africa and South America'. We obtained epidemiological data of 2417 COVID-19 cases reported by 40 countries in SSA within 30 days of the first case confirmed in Nigeria on 27 February. Out of 442 cases which had travel history available, only one (0.2%) had a travel history to China. These findings underline the result of the model. However, the fact that there were numbers of imported cases from other regions shows the limits of the model. The limits could be attributed to the characteristics of the COVID-19 which is infectious even when the patients do not express any symptoms. Therefore, there is a profound need for all modelling researchers to take asymptomatic cases into account when they establish modelling studies.

Underestimation of COVID-19 cases in Japan: an analysis of RT-PCR testing for COVID-19 among 47 prefectures in Japan.

BACKGROUND: Under the unique Japanese policy to restrict reverse transcriptase-polymerase chain reaction (RT-PCR) testing against severe acute respiratory syndrome coronavirus 2, a nationwide number of its confirmed cases and mortality remains to be low. Yet the information is lacking on geographical differences of these measures and their associated factors. AIM: Evaluation of prefecture-based geographical differences and associated predictors for the incidence and number of RT-PCR tests for coronavirus disease 2019 (COVID-19). DESIGN: Cross-sectional study using regression and correlation analysis. METHODS: We retrieved domestic laboratory-confirmed cases, deaths and the number of RT-PCR testing for COVID-19 from 15 January to 6 April 2020 in 47 prefectures in Japan, using publicly available data by the Ministry of Health, Labour and Welfare. We did descriptive analyses of these three measures and identified significant predictors for the incidence and RT-PCR testing through multiple regression analyses and correlates with the number of deaths through correlation analysis. RESULTS: The median prefectural-level incidence and number of RT-PCR testing per 100 000 population were 1.14 and 38.6, respectively. Multiple regression analyses revealed that significant predictors for the incidence were prefectural-level population (P < 0.001) and the number of RT-PCR testing (P = 0.03); and those for RT-PCR testing were the incidence (P = 0.025), available beds (P = 0.045) and cluster infections (P = 0.034). CONCLUSION: Considering bidirectional association between the incidence and RT-PCR testing, there may have been an underdiagnosed population for the infection. The restraint policy for RT-PCR testing should be revisited to meet the increasing demand under the COVID-19 epidemic.

Characteristics of doctors' fatality due to COVID-19 in Western Europe and Asia-Pacific countries.

Under the coronavirus disease 2019 (COVID-19) pandemic, the deaths of healthcare professionals have been increasingly reported worldwide. We performed a cross-sectional, observational study using news reports on the websites among selected countries as of April 2020. We found 120 dead medical doctors due to COVID-19 in Western Europe and Asia-Pacific countries; 67 in Italy (47 in the Northern part), 34 in China (22 in Hubei), 6 in France, 4 in the UK, the USA and Spain and 1 in South Korea, respectively. Among them, 90% were men, and specialties were reported as general practitioners for 30% and as physicians for 11.6%. The overall proportions of dead medical doctors amounted to 1.9 per 10 000 confirmed cases and 30.2 per 10 000 dead cases, respectively. Proactive measures are warranted to protect doctors especially who often encounters with COVID-19 patients.

New physician specialty training system impact on distribution of trainees in Japan.

OBJECTIVES: The problem of uneven distribution of medical services and inequitable distribution of physicians is drawing much attention worldwide. Revealing how changes in the specialty training system in Japan have affected the distribution of doctors could help us understand this problem. In 2018, a new and standardized specialty training system was implemented by the Japanese Medical Specialty Board, which is recognized by the Ministry of Health, Labor and Welfare. The purpose of this study was to investigate how this new system has affected the geographical distribution of doctors commencing specialty training (trainees) and choice of specialty in Japan. STUDY DESIGN: Retrospective observational study. METHODS: The change in the number of trainees between the control period (2012-2014) and 2018 was investigated, taking into account the prefecture and specialty selected. Population, the proportion of residents aged 65 years or older (aging rate), and the total number of overall doctors in each prefecture were considered as the background characteristics of each prefecture. We created a Lorenz curve and calculated the Gini coefficient for the distribution of trainees. RESULTS: In 2018, the number of trainees per 100,000 population increased to 6.6 nationwide compared with 5.5 during the control period. The number of trainees per 100,000 population in 2018 increased in prefectures with a large population of ≧ 2,000,000, a low aging rate (<27%), and a high doctor density (≧ 250 doctors per 100,000 population). The Gini coefficient showed an increase to 0.226 in 2018 compared with only 0.160 during the control period. CONCLUSIONS: After the implementation of the new training system, there was an increase in the number of doctors enrolling in specialty programs, and the specialties other than internal medicine and surgery have attracted more trainees. Inequality in the distribution of doctors between urban and rural prefectures worsened. This indicates the need to explore new ways of balancing distribution while maintaining optimal opportunities for specialist training.

Trend in unequal geographical distribution of dentists by age and gender in Japan from 1996-2014.

OBJECTIVES: To evaluate the relationship between dentists' demographic changes and their uneven geographical distribution. METHODS: Secondary analysis of nationwide government surveys, to assess trends in the geographical distribution of dentists by gender and age from 1996 to 2014 in Japan. RESULTS: The Gini-coefficient for the number of dentists per population from 47 prefectures decreased from 0.084 in 1996 to 0.069 in 2014. The coefficients for female (0.124-0.144) were higher than for male dentists (0.058-0.081). Coefficients for dentists aged 60 and older were lower than those for dentists younger than 40 in 2014 (male: 0.060 vs. 0.112; female: 0.107 vs. 0.169). CONCLUSION: The geographical maldistribution of dentists in Japan has improved. Demographic changes among dentists, including the increasing number of female dentists, could moderate this improvement.

Trend in unequal geographical distribution of doctors by age and sex in Japan from 2004 to 2014.

OBJECTIVES: In Japan, the proportion of female doctors and elderly doctors is increasing as in other countries. We investigated the relationship between doctors' demographic changes and their geographical distribution. STUDY DESIGN: A national database study. METHODS: We assessed trends in unequal geographical distribution of the number of doctors by sex and age from 2004 to 2014 in Japan. RESULTS: The Gini coefficient values for the number of female doctors (0.18) were larger than those for male doctors across all generations (0.13-0.14). The Gini coefficient values for the number of elderly doctors aged 60 years and older (male: 0.12, female: 0.18-0.23) were larger than those for majority age groups aged 40-59 years (male: 0.10, female: 0.16-0.17). CONCLUSION: The persisting geographical maldistribution of doctors may be associated with demographic changes, such as increase in the number of female doctors.

Impact of glucose fluctuation and monocyte subsets on coronary plaque rupture.

BACKGROUND AND AIMS: It remains unclear whether glycemic fluctuation can affect plaque rupture in acute myocardial infarction (AMI). Here we investigate the impact of glucose fluctuation on plaque rupture, as observed by optical coherence tomography (OCT), and monocyte subsets in patients with AMI. METHODS AND RESULTS: We studied 37 consecutive patients with AMI. All patients underwent OCT examination, which revealed 24 patients with plaque rupture and 13 patients without plaque rupture at the culprit site. Peripheral blood sampling was performed on admission. Three monocyte subsets (CD14(+)CD16(-), CD14(bright)CD16(+), and CD14(dim)CD16(+)) were assessed by flow cytometry. Glycemic variability, expressed as the mean amplitude of glycemic excursion (MAGE), was determined by a continuous glucose monitoring system 7 days after the onset of AMI. MAGE was significantly higher in the rupture patients than in the non-rupture patients (P=0.036). Levels of CD14(bright)CD16(+) monocytes from the rupture patients were significantly higher than those from the non-rupture patients (P=0.042). Of interest, levels of CD14(bright)CD16(+) monocytes correlated positively and significantly with MAGE (r=0.39, P=0.02). CONCLUSION: Dynamic glucose fluctuation may be associated with coronary plaque rupture, possibly through the preferential increase in CD14(bright)CD16(+) monocyte levels.

Experimental evidence of nonthermal acceleration of relativistic electrons by an intensive laser pulse.

Nonthermal acceleration of relativistic electrons is investigated with an intensive laser pulse. An energy distribution function of energetic particles in the universe or cosmic rays is well represented by a power-law spectrum, therefore, nonthermal acceleration is essential to understand the origin of cosmic rays. A possible candidate for the origin of cosmic rays is wakefield acceleration at relativistic astrophysical perpendicular shocks. The wakefield is considered to be excited by large-amplitude precursor light waves in the upstream of the shocks. Substituting an intensive laser pulse for the large amplitude light waves, we performed a model experiment of the shock environments in a laboratory plasma. An intensive laser pulse was propagated in a plasma tube created by imploding a hollow polystyrene cylinder, as the large amplitude light waves propagated in the upstream plasma at an astrophysical shock. Nonthermal electrons were generated, and the energy distribution functions of the electrons have a power-law component with an index of ~2. We described the detailed procedures to obtain the nonthermal components from data obtained by an electron spectrometer.