Intestinal Parasitic Infections of School Children in Kwale District of Coast Province, Kenya

The study was carried out to determine the geographical distribution of intestinal parasitic infection in Kwale district, Kenya in 1981. Stool specimens were obtained from the school children and were examined for the presence of both helminth ova and protozoan cysts. Entamoeba coli, Ascaris lumbricoides, hookworm and Trichuris trichiura were found to be common in the area. The prevalence of ascariasis and trichuriasis showed similar geographical distribution among divisions. The prevalence were high in both Central and Southhern but relatively low in Kinango and Kubo divisions. However, the geographical distribution of prevalence of E. coli and hookworm infections were different from those of ascariasis and trichuriasis. These results might reflect the differences of the population densities, the water sources and the sanitary conditions

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

Background: The EMPA KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population. Methods: EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110. Findings: Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5–2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62–0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16–1·59), representing a 50% (42–58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1). Interpretation: In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease. Funding: Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council

東アフリカ・ケニア，タベタ地区における住血吸虫症の病原保有宿主としての野生ネズミ類に関する研究

この研究は，1974年，1975年および1976年の乾期(9月-12月)にケニア南部のタベタ地区に於て行われた。マンソン住血吸虫の濃厚浸淫地であるJipe部落のJipe湖畔においてはPelomyssp.41個体，Arvicanthis sp.2個体，Dendromus sp.6個体，Thamnomys sp.5個体，Rattus rattus 1個体を採集した。このうち，Pelomys sp. 18個体(43.9%)に住血吸虫の自然感染を認めた。マンソン住血吸虫とビルハルツ住血吸虫の両種の浸淫地であるEldoro部落ではPelomys sp.4個体，Arvicanthis sp.3個体，Mastomys sp.3個体を採集し，そのうちPelomys sp.1個体(25.0%)に住血吸虫の自然感染を証明した。ビルハルツ住血吸虫の濃厚浸淫地であるKivalwa部落ではPelomys sp.1個体，Arvicanthis sp.10個体，Mastomys sp.7個体を採集したが，住血吸虫の感染は認められまかった。Pelomys sp.から得られた住血吸虫の成虫について，雄では腸管が食道腺の直後において2分し，虫体の前方から2/5ないしは2/6の位置において再融合するものが普通にみられた。精巣の数は5-7個であった。雌では単純ま卵巣が体の前部に位置し，子宮内に認められる虫卵の数は1個であった。また，その卵の形態は卵円形を呈し， 鈍角をなす卵殻端に近い側部に著しい棘を生ずる。その100個の計測値は長径143.2±12.19μ，幅径57.7±6.58μ であった。更に孵化させて得たミラシジウムをJipe湖中に多数生息するBiomphalaria sudanicaに実験的に感染させたところ， セルカリアまでの発育が認められた。これらの特徴をヒトから得たマンソン住血吸虫のそれと比較したところ，多くの点で一致がみられた。従ってPelomys sp.から得られた住血吸虫をマンソン住血吸虫と同定した。Jipe 部落にはマンソン住血吸虫による患者が多数みられ，この住血吸虫の病原保有宿主として，Pelomys属のネズミが，疫学上，重要な役割を演じているものと推測された。These investigations were carried out in some of the villages around Taveta Town, Coast Province, Kenya, during the dry seasons of 1974, 1975 and 1976. The authors examined 83 wild rodents from villages where there is a high infection rate of S. mansoni and/or S. haematobium. The number and species of the rodents collected were as follows: 41 Pelomys sp., 2 Arvicanthis sp., 6 Dendromus sp., 5 Thamnomys sp., 1 Rattus rattus from jipe, 4 Pelomys sp., 3 Arvicanthis sp., 3 Mastomys sp. from Eldoro, 1 Pelomys sp., 10 Arvicanthis sp., 7 Mastomys sp. from Kivalwa. Among them, 18 Pelomys sp. (43.9%) from Jipe and 1 Pelomys sp. (25.0%) from Eldoro proved to be infected with Schistosoma flukes. These flukes were identified as S. mansoni on the basis of their morphological features as well as the infectivity to their transmitters. In the experimental exposure of Biomphalaria sudanica to miracidia obtained from Pelomys sp., a number of cercariae were observed. This snail also proved to be infected with S. mansoni from human infection. From these investigations, it was suggested that the creek rodent, Pelomys sp. may play the role as a reservoir host of Schistosoma mansoni in this area

東アフリカ・ケニア，タベタ地区におけるヒト住血吸虫症の浸淫状況

1974年にタベタ地区の3村落の住民に皮内反応と検使，検尿による住血吸虫卵の検出を試み，963名の結果について集計を行った。皮内反応の抗原としてはVBS adult S.japonicum antigen (1:10,000 dilution)を用い，糞便と尿の検体は集卵法l乙て検査した。虫卵陽性率はJipe 62.2%，Eldoro 68.0%, Kivalwa 69.6 %であった。Jipeでは主にS.mansoni，KivalwaではS.haematobium，Eldoroでは両種の浸淫が認められた。Eldoroでは男性より女性に虫卵陽性率が高かったが，JipeとKivalwaでは推計学的に虫卵陽性率の有意な性差は認められなかった。虫卵陽性率は小児では年齢と共に上昇し，5歳と14歳の間で最高値に達し，以後次第に減少した。皮内反応の陽性率は全体で76.4%で，虫卵陽性率より高い。小児では虫卵陽性者の多数で，皮内反応は弱いか或は全く反応を呈さなかった。皮内反応陽性率は年齢と共に増加し，40歳以上の住民では95%に達した。Jipeでは女性より男性に皮反内応陽性率が高かったが， EldoroとKivalwaでは性差は認められなかった。虫卵陽性の者ではS.mansoni感染者とS.haematobium感染者の聞に皮内反応の差は認められなかった。1975年にJipe，Kivalwa，Kuwahoma，Chalaの村落住民に検便と検尿を行った。KuwahomaではS.haematobiumの浸淫が認められた。Chalaでは住血吸虫の感染は稀であった。この限られた地域にそれぞれS.mansoni，S. haematobiumの感染が流行する村落，両種の感染の流行する村落が存在することが確認された。これら両種の住血吸虫症の流行する地域の疫学的調査に於て，皮内反応にVBS adult S. japonicum antigenを，検便，検尿に集卵法を用い得ることが明らかにされた。A total of 963 individuals in three villages were examined for schistosomiasis by both skin test and schistosome ova detection in stool and urine in 1974. The antigen used for skin test was VBS adult S. japonicum antigen (1: 10,000 dilution). Stool and urine samples were examined through the concentration methods. Egg-positive rate was 62.2 per cent in Jipe, 68.0 per cent in Eldoro, 69.6 per cent in Kivalwa. Jipe was infested mostly by S. mansoni, Kivalwa by S. haematobium and Eldoro by both two schistosomes. The egg-positive rate was higher in females than in males in Eldoro. In Jipe and Kivalwa, however, the differences in the rate between males and females were not statistically significant. The rate increased with age in children, reached a peak between the ages of 5 and 14 years and then decreased gradually. The positive rate of skin test was 76.4 per cent in total, higher than that of stool and urine examinations. The skin reaction was weak or absent among many egg-positive children. The skin-test positive rate increased as the age advanced and reached 95 per cent in inhabitants from 40 years up. The positive rate of skin test was higher among males than females in Jipe. No significant difference in the rate between males and females was found in Eldoro and Kivalwa. Among the egg-positive subjects there was no significant difference in skin reaction between S. mansoni infection and S. haematobium infection. In 1975 stool and urine samples from Jipe, Kivalwa, Kuwahoma and Chala were examined. Kuwahoma proved to be infested by S. haematobium. In Chala schistosome infection was rare. There exist villages infested by S. mansoni and/or S. haematobium in the small area. It seems that VBS adult S. japonicum antigen for skin test and the concentration methods for stool and urine examinations are of use in the epidemiological survey in the areas where S. mansoni and/or S. haematobium infections are prevailing

東アフリカ・ケニア，タベタ地区における住血吸虫症の媒介貝類について

ケニア国タベタ地区での淡水産貝類は以下の8属11種である。即ちBiomphalaria pfeifferi(Krauss)，B. sudanica (Martens)，Bulinus globosus (Morelet)，B. tropicus (Krauss)，B.forskalii (Ehrenberg)，以上5種は住血吸虫との関係種，Lymnea natalensis (Krauss)，Ceratophallus natalensis(Krauss)，Segmentorbis angustus (Jickeli)，Gyraulus costulatus (Krauss)，Bellamya unicolor (Olivier)，Melanoides tuberculata (Muller)である。B. pfeifferiはLumi川と灌漑用溝に， B. sudanicaはJipe湖畔に，それぞれの多数の棲息をみたが，マンソン住血吸虫の自然感染はB. pfeifferiのみに見られた。B.globosusは灌漑用溝のみに多数棲息し，B. tropicusは灌漑用溝とJipe湖畔に，B. forskaliiは少数ながらあらゆる水系に見出された。ビルハルツ住血吸虫の自然感染はB. globosusのみに見出され，その貝の棲息数が多いと約10%の高い感染率が常時認められた。一方これらの実験感染では，B. pfeifferiには3隻のミラシジウムで，B. sudanicaには5隻のそれで100%感染が成立し，両種ともマンソン住血吸虫の好適な中間宿主であることがわかった。B. globosusは1.5～8.5mmの若い貝は5隻のミラシジウムで100%感染が成立し，11～12mmの成貝では20隻以上のミラシジウムが必要である。ビルハルツ住血吸虫の好適な中間宿主であることがわかった。以上からタベタ地区でのマンソン住血吸虫症，ピノレハルツ住血吸虫症の媒介中間宿主として，前者にはB. pfeifferiとB. sudanicaが，後者にはB.globosusが主な役割を演じていることが推測される。The present study was carried out in the permanent water streams of Lumi River, Irrigation Furrow and Lake Jipe in the Taveta area, Coast Province, Kenya during the dry seasons of 1974 and 1975, and the experimental infection was made at laboratory in Japan. Freshwater snails collected in the Taveta area were as follows: Biomphalaria pfeifferi (Krauss), B. sudanica (Martens), Bulinus globosus (Morelet), B. tropicus (Krauss), B. forskalii (Ehrenberg), Lymnea natalensis (Krauss), Ceratophallus natalensis (Krauss), Segmentorbis angustus (Jickeli), Gyraulus costulatus (Krauss), Bellamya unicolor (Olivier) and Melanoides tuberculata (Muller). B. pfeifferi was commonly found in river and irrigation canal, whereas B. sudanica only in lake. Natural infection of Schistosoma mansoni was found in B. pfeifferi, but not in B. sudanica. Both the two species were experimentally proved to be suitable intermediate snail hosts of S. mansoni. Therefore it was indicated that B. pfeifferi is the host snail of S. mansoni in the endemic area along river and irrigation canal while B. sudanica is suspected of playing the role in the transmission of S. mansoni in lakeshore. B. globosus was commonly found in irrigation canal. Around 10 per cent of the snails proved to be naturally infected with S. haematobium on the conditions that many snails occurred. This snail was also experimentally proved to be susceptible to S. haematobium. B. forskalii was widespread, but the snail density seemed to be low. B. tropicus is well known as the not-intermediate snail host of S. haematobium. Therefore there might be a possibility to contribute only by B. globosus to the transmission of S. haematobium in this area

東アフリカ・ケニア，タベタ地区における住血吸虫症の媒介貝類について

ケニア国タベタ地区での淡水産貝類は以下の8属11種である。即ちBiomphalaria pfeifferi(Krauss)，B. sudanica (Martens)，Bulinus globosus (Morelet)，B. tropicus (Krauss)，B.forskalii (Ehrenberg)，以上5種は住血吸虫との関係種，Lymnea natalensis (Krauss)，Ceratophallus natalensis(Krauss)，Segmentorbis angustus (Jickeli)，Gyraulus costulatus (Krauss)，Bellamya unicolor (Olivier)，Melanoides tuberculata (Muller)である。B. pfeifferiはLumi川と灌漑用溝に， B. sudanicaはJipe湖畔に，それぞれの多数の棲息をみたが，マンソン住血吸虫の自然感染はB. pfeifferiのみに見られた。B.globosusは灌漑用溝のみに多数棲息し，B. tropicusは灌漑用溝とJipe湖畔に，B. forskaliiは少数ながらあらゆる水系に見出された。ビルハルツ住血吸虫の自然感染はB. globosusのみに見出され，その貝の棲息数が多いと約10%の高い感染率が常時認められた。一方これらの実験感染では，B. pfeifferiには3隻のミラシジウムで，B. sudanicaには5隻のそれで100%感染が成立し，両種ともマンソン住血吸虫の好適な中間宿主であることがわかった。B. globosusは1.5～8.5mmの若い貝は5隻のミラシジウムで100%感染が成立し，11～12mmの成貝では20隻以上のミラシジウムが必要である。ビルハルツ住血吸虫の好適な中間宿主であることがわかった。以上からタベタ地区でのマンソン住血吸虫症，ピノレハルツ住血吸虫症の媒介中間宿主として，前者にはB. pfeifferiとB. sudanicaが，後者にはB.globosusが主な役割を演じていることが推測される。The present study was carried out in the permanent water streams of Lumi River, Irrigation Furrow and Lake Jipe in the Taveta area, Coast Province, Kenya during the dry seasons of 1974 and 1975, and the experimental infection was made at laboratory in Japan. Freshwater snails collected in the Taveta area were as follows: Biomphalaria pfeifferi (Krauss), B. sudanica (Martens), Bulinus globosus (Morelet), B. tropicus (Krauss), B. forskalii (Ehrenberg), Lymnea natalensis (Krauss), Ceratophallus natalensis (Krauss), Segmentorbis angustus (Jickeli), Gyraulus costulatus (Krauss), Bellamya unicolor (Olivier) and Melanoides tuberculata (Muller). B. pfeifferi was commonly found in river and irrigation canal, whereas B. sudanica only in lake. Natural infection of Schistosoma mansoni was found in B. pfeifferi, but not in B. sudanica. Both the two species were experimentally proved to be suitable intermediate snail hosts of S. mansoni. Therefore it was indicated that B. pfeifferi is the host snail of S. mansoni in the endemic area along river and irrigation canal while B. sudanica is suspected of playing the role in the transmission of S. mansoni in lakeshore. B. globosus was commonly found in irrigation canal. Around 10 per cent of the snails proved to be naturally infected with S. haematobium on the conditions that many snails occurred. This snail was also experimentally proved to be susceptible to S. haematobium. B. forskalii was widespread, but the snail density seemed to be low. B. tropicus is well known as the not-intermediate snail host of S. haematobium. Therefore there might be a possibility to contribute only by B. globosus to the transmission of S. haematobium in this area