Invasive Pneumococcal Disease diminish during the onset of COVID-19 in Japan between 2019 and 2022

Invasive pneumococcal disease (IPD) is a severe infection caused by Streptococcus pneumoniae. This study explores the influence of COVID-19 on IPD occurrence in Japan by using the time trend analysis. We found that the IPD trend changed dramatically after the emergence of COVID-19; first, the number of IPD cases decreased. Second, the seasonality of IPD disappeared after the COVID-19 pandemic. Interestingly, the number of IPD cases increased between the waves of COVID-19

Determinants of Willingness to Pay for Fecal Sludge Management Services and Knowledge Gaps: A Scoping Review

Achieving universal access to safely managed sanitation services is one of the Sustainable Development Goal 6 targets (SDG6.2). The cost and availability of services to ensure the safe management of on-site sanitation, such as pit latrines and septic tanks, can be major barriers for poor households. Particularly, fecal sludge emptying services have become increasingly important due to the growing urban population. This review aims to scope the literature on stated and revealed willingness to pay (WTP) for emptying on-site sanitation systems and to identify determinants of WTP and gaps in knowledge. We performed electronic searches of six databases. After deduplication, 1846 records were identified, of which 14 were included in the review. In these studies, we identified 26 distinct scenarios that reported mean or median WTP values for emptying services and their market price (i.e., price at which the services were provided). Among the 26 scenarios, 77% (n = 20) reported that WTP was lower than the market price. We identified 20 statistically significant determinants of WTP, which can be leveraged when developing or improving manual and mechanical emptying services to attract more customers. Future research should consider services that adopt flexible pricing or mobile money payment and optimize their emptying operations to increase WTP. Validating the effectiveness of such services in solving the WTP-market price imbalance is a significant knowledge gap

Prevalence and risk factors of Schistosoma mansoni infection among children under two years of age in Mbita, Western Kenya.

Despite growing evidence that infants and very young children can be infected with schistosomes, the epidemiological features and risk factors are not well described in this age group. We aimed to assess the prevalence of S. mansoni infection in children under two years of age from a population with a known high burden of infection in school-aged children and adults and thus inform the need for interventions in this potentially vulnerable age group. In a cross-sectional study in Mbita Sub-county, along the east coast of Lake Victoria, Western Kenya, we enrolled 361 children aged 6-23 months. The prevalence of S. mansoni infection was detected using the Kato-Katz stool examination and a point-of-care test for urinary circulating cathodic antigen (POC-CCA) (Rapid Medical Diagnostics, Pretoria, South Africa). Three-hundred and five (305) children had complete data of whom 276 (90.5%, 95%CI: 86.6-93.5) children were positive for S. mansoni by the POC-CCA test, while 11 (3.6%, 95%CI: 1.8-6.4) were positive by the Kato-Katz method. All Kato-Katz positive cases were also positive by the POC-CCA test. In multivariable analysis, only geographical area, Rusinga West (AOR = 7.1, 95%CI: 1.4-35.2, P = 0.02), was associated with S. mansoni infection using Kato-Katz test. Independent associations for POC-CCA positivity included age, (12-17 months vs 6-11 months; AOR = 7.8, 95%CI: 1.8-32.6, P = 0.002) and breastfeeding in the previous 24 hours (AOR = 3.4, 95%CI: 1.3-9.0, P = 0.009). We found a potentially very high prevalence of S. mansoni infection among children under two years of age based on POC-CCA test results in Mbita Sub-county, Kenya, which if confirmed strongly supports the need to include infants in public health strategies providing universal prophylactic treatment in high burden settings. Further research is required to determine the accuracy of diagnostic tools to detect light infection among very young children and possible long-term health impacts

IL-17Aは赤痢アメーバの腸管感染においてIFN-γ/IL-4比の減少と持続感染に寄与する

Amebiasis is an infectious disease caused by Entamoeba histolytica, an anaerobic protozoan parasite, and is a major public health problem worldwide, particularly in areas with inadequate sanitation and poor hygiene. Th1 responses, represented by interferon gamma (IFN-γ), play a protective role by clearing the amebae from the gut, whereas Th2 responses are responsible for chronic infection. Th17 responses preconditioned by vaccination or by modulating the intestinal microbiome protect mice from the settlement of E. histolytica. However, the role of interleukin-17A (IL-17A), which is upregulated during the natural course of intestinal amebiasis, has not been clarified. The aim of this study was to investigate the role of IL-17A during intestinal amebiasis in a mouse model. IL-17A knockout and wild-type CBA/J mice were challenged intracecally with 2 × 106 E. histolytica trophozoites, and their infection, pathology, and immune responses were monitored. Neither the initial settlement of E. histolytica nor the inflammation of the cecum was affected by the absence of IL-17A for week 1, but the infection rate and parasite burden declined in a late stage of infection, accompanied by an increased IFN-γ/IL-4 ratio. Therefore, IL-17A contributes to the persistence of E. histolytica and modulates the immune response, including the IFN-γ/IL-4 ratio, which may be responsible for the reduction of the parasite burden in the IL-17A knockout mice during the chronic phase of intestinal amebiasis.長崎大学学位論文 学位記番号:博(医歯薬)甲第1005号 学位授与年月日:平成29年12月6日Author: Sharmina Deloer, Risa Nakamura, Mihoko Kikuchi, Taeko Moriyasu, Yombo Dan Justin Kalenda, Eman Sayed Mohammed, Masachika Senba, Yoichiro Iwakura, Hiroki Yoshida, Shinjiro HamanoCitation: Parasitology International, 66(6), pp.817-823; 2017Nagasaki University (長崎大学)課程博

The current status of neglected tropical diseases in Japan: A scoping review.

Little attention has been paid to neglected tropical diseases (NTDs) in high-income countries and no literature provides an overview of NTDs in Japan. This scoping review aims to synthesize the latest evidence and information to understand epidemiology of and public health response to NTDs in Japan. Using three academic databases, we retrieved articles that mentioned NTDs in Japan, written in English or Japanese, and published between 2010 and 2020. Websites of key public health institutions and medical societies were also explored. From these sources of information, we extracted data that were relevant to answering our research questions. Our findings revealed the transmission of alveolar echinococcosis, Buruli ulcer, Chagas disease, dengue, foodborne trematodiases, mycetoma, scabies, and soil-transmitted helminthiasis as well as occurrence of snakebites within Japan. Other NTDs, such as chikungunya, cystic echinococcosis, cysticercosis, leishmaniasis, leprosy, lymphatic filariasis, rabies, and schistosomiasis, have been imported into the country. Government agencies tend to organize surveillance and control programs only for the NTDs targeted by the Infectious Disease Control Law, namely, echinococcosis, rabies, dengue, and chikungunya. At least one laboratory offers diagnostic testing for each NTD except for dracunculiasis, human African trypanosomiasis, onchocerciasis, and yaws. No medicine is approved for treatment of Chagas disease and fascioliasis and only off-label use drugs are available for cysticercosis, opisthorchiasis, human African trypanosomiasis, onchocerciasis, schistosomiasis, and yaws. Based on these findings, we developed disease-specific recommendations. In addition, three policy issues are discussed, such as lack of legal frameworks to organize responses to some NTDs, overreliance on researchers to procure some NTD products, and unaffordability of unapproved NTD medicines. Japan should recognize the presence of NTDs within the country and need to address them as a national effort. The implications of our findings extend beyond Japan, emphasizing the need to study, recognize, and address NTDs even in high-income countries

Determinants of Willingness to Pay for Fecal Sludge Management Services and Knowledge Gaps: A Scoping Review

Achieving universal access to safely managed sanitation services is one of the Sustainable Development Goal 6 targets (SDG6.2). The cost and availability of services to ensure the safe management of on-site sanitation, such as pit latrines and septic tanks, can be major barriers for poor households. Particularly, fecal sludge emptying services have become increasingly important due to the growing urban population. This review aims to scope the literature on stated and revealed willingness to pay (WTP) for emptying on-site sanitation systems and to identify determinants of WTP and gaps in knowledge. We performed electronic searches of six databases. After deduplication, 1846 records were identified, of which 14 were included in the review. In these studies, we identified 26 distinct scenarios that reported mean or median WTP values for emptying services and their market price (i.e., price at which the services were provided). Among the 26 scenarios, 77% (n = 20) reported that WTP was lower than the market price. We identified 20 statistically significant determinants of WTP, which can be leveraged when developing or improving manual and mechanical emptying services to attract more customers. Future research should consider services that adopt flexible pricing or mobile money payment and optimize their emptying operations to increase WTP. Validating the effectiveness of such services in solving the WTP–market price imbalance is a significant knowledge gap

<i>Schistosoma mansoni</i> infection suppresses the growth of <i>Plasmodium yoelii</i> parasites in the liver and reduces gametocyte infectivity to mosquitoes

<div><p>Malaria and schistosomiasis are major parasitic diseases causing morbidity and mortality in the tropics. Epidemiological surveys have revealed coinfection rates of up to 30% among children in Sub-Saharan Africa. To investigate the impact of coinfection of these two parasites on disease epidemiology and pathology, we carried out coinfection studies using <i>Plasmodium yoelii</i> and <i>Schistosoma mansoni</i> in mice. Malaria parasite growth in the liver following sporozoite inoculation is significantly inhibited in mice infected with <i>S</i>. <i>mansoni</i>, so that when low numbers of sporozoites are inoculated, there is a large reduction in the percentage of mice that go on to develop blood stage malaria. Furthermore, gametocyte infectivity is much reduced in mice with <i>S</i>. <i>mansoni</i> infections. These results have profound implications for understanding the interactions between <i>Plasmodium</i> and <i>Schistosoma</i> species, and have implications for the control of malaria in schistosome endemic areas.</p></div

Gametocyte infectivity.

<p>(A) Parasitemia. Female BALB/c mice were each inoculated with 1 x 10⁶ <i>Plasmodium yoelii</i> parasitized erythrocytes intravenously with (n = 4 mice) or without (n = 5) pre-existing <i>Schistosoma mansoni</i> infection. Parasitaemia was determined by microscopic examination on days 3, 4, and 5 post-inoculation; day 3: Student’s two-tailed t-test; **P<0.01, t = -4.906, df = 7; Day5: *P<0.05, t = -2.922, df = 5 (<b>B</b>) Gametocyte density. Gametocyte density was determined on days 3 and 4 post-inoculation of 1 x 10⁶ <i>P</i>. <i>yoelii</i>-parasitized erythrocytes intravenously. Day 3: Student’s two-tailed t-test; **P<0.01, t = 3.813, df = 5; Day 4: **P<0.01, t = 3.608, df = 5. Error bars show the geometric mean with 95% confidence intervals. (C) Percentage of mosquitoes with one or more oocysts present on the midgut eight days post-feeding on infected mice. A minimum of eight mosquitoes were allowed to feed on each individual mouse in the group per day **P = 0.0003, (2-way ANOVA, F = 22.23, DFn = 1, DFd = 14). Error bars mar the standard error of the mean per mouse group. (D) Oocyst numbers per mosquito. The numbers of oocysts present on mosquito midguts were determined eight days post-mosquito feeding; day 3: Student’s two-tailed t-test, **P<0.01, t = 3.077, df = 25. Error bars show the geometric mean with 95% confidence intervals. Data is representative of three independent experiments.</p

Growth of malaria parasites in the liver and blood of mice following SPZ inoculation of <i>Plasmodium yoelii</i> with and without <i>Schistosoma mansoni</i> infection.

<p>(A) Copy number of <i>P</i>. <i>yoelii</i> 18s RNA gene per 1×10⁶mouse G3PDH gene measured at 42 h post SPZ inoculation. Female BALB/c mice (N = 6) infected with 50 <i>S</i>. <i>mansoni</i>-cercariae 10 weeks previously were challenged with 1,500 <i>P</i>. <i>yoelii</i> SPZ along with <i>S</i>. <i>mansoni</i>-non-infected controls. **P<0.01, Student’s two-tailed t-test, t = 4.362, df = 10. (B) Parasitaemia. Blood stage malaria parasites were monitored daily from day 2 to 8 post i.v. inoculation of 500 <i>P</i>. <i>yoelii</i> SPZ. (C) Percentage survival. Data from one representative experiment of three independent repeats are shown.</p