Enterobius vermicularis egg positive rate in a primary school in Chungchongnam-do (province) in Korea

The egg positive rate of Enterobius vermicularis was investigated among students of a primary school and a kindergarten located in the rural area of Tangjin-gun, Chungchongnam-do in December, 1998. Of the 189 examinees, 28 (14.8%) were found to be infected with E. vermicularis by the adhesive cellotape anal swab method. The infection rates ranged from 4.2% to 26.1% among school children, and the highest rate was observed in children attending kindergarten. Three months after treatment with albendazole, four (14.3%) out of 28 infected children still remained infected with E. vermicularis. Through this survey, we were able to determine that E. vermicularis infection is still prevalent among children in rural areas of Korea.     

Infection status of intestinal parasites in children living in residential institutions in Metro Manila, the Philippines

A small scale survey was performed to know the infection status of intestinal parasite in children of the residential institutions and street communities in Metro Manila, Philippines. A total of 284 stool samples from 11 institutions and 3 street communities was examined by the formalin-ether concentration method. The scotch tape anal swab was adapted to 121 children to investigate the infection status of Enterovius vermicularis. It was found out that 62.0% of the children examined were positive for one or more intestinal parasites. Multiple infections were observed in 34.2% of the children. Among 172 children who gave detail information, the prevalence for Ascaris lumbricoides, Trichuris trichiura, and hookworm was 36.0%, 44.8%, and 7.0% respectively. Of the children examined, 47.7% were found to be harboring parasitic protozoans such as Entamoeba histolytica, Giardia lamblia, and Blastocystis hominis. The most prevalent of these protozoans was B. hominis with an infection rate of 40.7%. The prevalence of these infections among children living in institutions was relatively high. More efforts should be made to implement anthelminthic programs including bi-annual follow-up treatments.     

Immunization interview survey in the Mongolian People's Republic.

An immunization interview survey was carried out in the urban and rural areas of Mongolia. The population sample interrogated comprised 1359 households with 6994 household members, 3634 of them younger than 15 years. The data collection unit was a private household, where information on administrative, demographic and socio-economic items was obtained in addition to detailed information on vaccination histories. A fair number of individuals with a positive history was found among children aged 1 to 5 years; the highest rates were determined among preschool and school-children aged 5 to 9. Significant differences in vaccination rates were found between urban and rural dwellers, urban areas displaying a higher proportion of vaccinated children in the younger age groups and rural areas among school-age children. A significantly higher proportion of vaccinated individuals was found among children living in somons than those living in aimac centres. No significant differences were found between children attending child collective institutions and those educated solely at home. The immunization interview survey was specially directed toward obtaining an estimate of the vaccinated population segment with reference to age in demarcated areas and thus detecting "weak spots" requiring remedial action.     

Intestinal parasite infections in pigs and beef cattle in rural areas of Chungcheongnam-do, Korea

The present study was performed to investigate the infection status of intestinal parasites in pigs and beef cattle in rural areas of Chungcheongnam-do, Korea. From November 2009 to April 2010, a total of 241 fecal samples of pigs and beef cattle (136 and 105, respectively) were examined by direct smear and centrifugal sedimentation methods. The overall positive rates of intestinal parasites among pigs and beef cattle were 73.5% and 4.8%, respectively, and the double-infection rate was 10.3% in pigs. Of 136 specimens from pigs, Balantidium coli, Ascaris suum, and Entamoeba spp. infections were found in 88 (64.7%), 24 (17.6%), and 5 cases (3.7%), respectively. Of 105 beef cattle, Entamoeba spp. infections were detected in 5 cases (4.8%). From these results, it is shown that pigs raised on rural farms in Chungcheongnam-do had a high B. coli infection rate and a moderate A. suum infection rate. These results demonstrate that environmentally resistant cysts or eggs could be widespread on the farms examined, and thus an effective hygienic management system is needed to prevent them from serving as the source of infection for human beings.     

Notes about the impact of human seasonal migration on malaria spreading in rural Venezuela

This paper considers the effect of social and cultural factors on malaria spreading in rural Venezuela. It argues that standard vertical malaria control programs are inclined to ignore local workplace and living conditions instead of recruiting traditional practices into the planning scenario for more effective malaria control. An epidemiological survey on people migrating from malaria endemic areas to non-endemic region studied by blood films and a Plasmodium falciparum in vivo test. The results of the survey on people migrating from malaria endemic areas to non endemic regions revealed that 138 (118 males and 20 females) (23.3%) had fever (38.2-39 degrees C), malarial parasites were detected in the blood films of 49 (35.5%) from 138 febrile (parasitaemic) patients, and 45 (91.8%) of the parasitaemic cases were infected with P. falciparum; other four cases carried P. vivax only. Differences in prevalence, parasites load and the density of infection were observed between the three age groups. The asexual parasite load and the density of parasites (asexual and sexual forms) were appreciably higher in older children than in the other two age-groups (P < 0.001 for each). In the Plasmodium falciparum in vivo test, nine (22.5%) patients presented resistance grade III. People with transient jobs in malaria endemic areas could transport the parasites to non-endemic areas establishing a new malaria focus during seasonal migration activities.     

Characterising co-infections with Plasmodium spp., Mansonella perstans or Loa loa in asymptomatic children,adults and elderly people living on Bioko Island using nucleic acids extracted from malaria rapid diagnostic tests

BackgroundRegular and comprehensive epidemiological surveys of the filarial nematodes Mansonella perstans and Loa loa in children, adolescents and adults living across Bioko Island, Equatorial Guinea are lacking. We aimed to demonstrate that blood retained on malaria rapid diagnostic tests, commonly deployed for malaria surveys, could be used as a source of nucleic acids for molecular based detection of M. perstans and L. loa. We wanted to determine the positivity rate and distribution of filarial nematodes across different age groups and geographical areas as well as to understand level of co-infections with malaria in an asymptomatic population.MethodologyM. perstans, L. loa and Plasmodium spp. parasites were monitored by qPCR in a cross-sectional study using DNA extracted from a subset malaria rapid diagnostic tests (mRDTs) collected during the annual malaria indicator survey conducted on Bioko Island in 2018.Principal findingsWe identified DNA specific for the two filarial nematodes investigated among 8.2% (263) of the 3214 RDTs screened. Positivity rates of M. perstans and L. loa were 6.6% and 1.5%, respectively. M. perstans infection were more prominent in male (10.5%) compared to female (3.9%) survey participants. M. perstans parasite density and positivity rate was higher among older people and the population living in rural areas. The socio-economic status of participants strongly influenced the infection rate with people belonging to the lowest socio-economic quintile more than 3 and 5 times more likely to be L. loa and M. perstans infected, respectively. No increased risk of being co-infected with Plasmodium spp. parasites was observed among the different age groups.Conclusions/SignificanceWe found otherwise asymptomatic individuals were infected with M. perstans and L. loa. Our study demonstrates that employing mRDTs probed with blood for malaria testing represents a promising, future tool to preserve and ship NAs at room temperature to laboratories for molecular, high-throughput diagnosis and genotyping of blood-dwelling nematode filarial infections. Using this approach, asymptomatic populations can be reached and surveyed for infectious diseases beyond malaria.     

Meningococcal infection in the Uzbek SSR

The epidemiological characteristics of meningococcal infection in Uzbekistan during the period of 8 years since its last epidemic rise in 1972 is presented. Differences in the intensity of the epidemic process among the urban and rural population due to a considerable isolation of most of the rural populated localities from the district centers and the low population density in the republic have been established. The seasonal distribution of the infection had a winter-spring character in urban areas and a spring character in rural areas. 63.4% of all cases were children under 14 years. In cities a high morbidity level among adolescents and young people was determined mainly by visitors from rural areas. A high epidemiological importance of healthy carriers, predominantly schoolchildren and young people was established. The immunological studies of humoral immunity in different groups of the population indicate that the process of immunization was more rapid in cities.     

Status of intestinal parasite infections among children in Bat Dambang, Cambodia

A survey was conducted to determine the extent of intestinal parasite infection in Bat Dambang, Cambodia in March 2004. A total of 623 fecal specimens was collected from kindergarten and schoolchildren and examined using the formalin-ether sedimentation technique. The overall infection rate of intestinal parasites was 25.7% (boys, 26.2%; girls, 25.1%), and the infection rates of intestinal helminthes by species were as follows: Echinostoma sp. 4.8%, hookworm 3.4%, Hymenolepis nana 1.3%, and Rhabditis sp. 1.3%. The infection rates of intestinal protozoa were; Entamoeba coli 4.8%, Giardia lamblia 2.9%, Iodamoeba butschlii 1.4%, Entamoeba polecki 1.1%, and Entamoeba histolytica 0.8%. There were no egg positive cases of Ascaris lumbricoides or Trichuris trichiura. All children infected were treated with albendazole, praziquantel, or metronidazole according to parasite species. The results showed that intestinal parasites are highly endemic in Bat Dambang, Cambodia.     

Housing quality and child mortality in the rural Philippines

Factors influencing child survival to age 5 are investigated for a rural sample in lloilo Province, Philippines. Considered are construction materials in walls, doors, windows, and floors and the typpes of toilet facilities. 707 women were asked how many children they had borne alive; the sexes and dates of each live birth; whether each child was still living; and if not at what age the child had died. This study focused retrospectively on mortality among 2359 children born between 1960 and 1973. About 4.9% had died before age 5. This is 1/2 of what was observed nationally for rural children in the 1978 fertility survey. Health conditions in rural Iloilo Province may have been more favorable than in other rural parts of the nation. Income generated from shipping, lumbering, and fish culture may have also contributed to the lower rate of child mortality observed in this sample. The sex ratio of the children was 102, well within the range regarded as typical. A logit regression was employed. Of the 207 girls with low demographic risk and worse quality housing, 249 were estimated to survive to age 5 and 18 to die before age 5. Sex was not an important factor in child mortality. Boys and girls had about equal chances of surviving. A social-demographic risk factor commonly linked with infant mortality is breast feeding. Breastfed infants from a number of developing countries have had lower rates of infant mortality. A slightly larger % of nonbreastfed children (96.9%) survived to age 5 than did breastfed children. Living in a poorly constructed dwelling reduced the odds of a child's survival. Estimates from the Brass method showed that the expected probability of children dying before age 5 was .073 and .035, representing life expectancies at birth of 63.4 and 69.9 years.     

The intestinal parasite infection status of inhabitants in the Roxas city,The Philippines

We carried out a small-scale survey to investigate the status of intestinal protozoa and helminthes infection of inhabitants in Roxas city, Mindoro, the Philippines. Total 301 stool samples were subjected to the formalin-ether concentration method for the detection of helminth ova and protozoan cysts. The overall positive rate was 64.5%, and that of male and female were 56.6% and 72.5%, respectively. The highest infected helminth was Ascaris lumbricoudes (51.2%), followed by Trichuris trichiura (27.6%), hookworm (8.0%) and Enterobius vermicularis (0.3%). The protozoa infection status revealed that Entamoeba coli was the most frequent (15.0%). Iodoamoeba buetschlii and E. histolytica were found but few. The multiple infection more than two parasites was 29.6%, and double infection with A. lumbricoides and T. trichiura was most common. The intestinal helminth infections were highly prevalent in this area, according to this result, and we concluded that anthelminthic drugs should be given to inhabitants, especially to children of 1 to 15 years-old.     

A survey of malarial infection in endemic areas of Savannakhet province, Lao PDR and comparative diagnostic efficiencies of Giemsa staining, acridine orange staining, and semi-nested multiplex PCR

Malaria remains one of the most important parasitic diseases in Lao PDR, especially in forested rural areas. Knowing the rate of infection using highly sensitive and specific methods, and the factors related to malarial infection, may be helpful in reducing the infection and mortality rates. We aimed to study the malarial infection rate by comparing three detection methods, i.e., Giemsa staining, acridine orange (AO) staining and semi-nested multiplex PCR. The study also included some factors related to malarial infection in the endemic areas of Savannakhet province, Lao PDR. The respective malarial infection rates by Giemsa staining, AO staining and semi-nested multiplex PCR in Houy Jang vs. Keng Thong villages were 13.1 vs. 20.8, 16.2 vs. 25.4 and 20.8 vs. 30.8%. The infection rate among children not over 10 years of age was higher than infection rate among the older ages (p = 0.002, Z-test for two proportions). The higher infection rates by semi-nested multiplex PCR over Giemsa and AO staining suggest the existence of many subclinical cases with low level parasitemia, undetected by microscopic techniques. We found no mixed infections using Giemsa or AO staining, but using semi-nested multiplex PCR we found 1.2% (3/260) mixed P. falciparum and P. vivax infections, suggesting that semi-nested multiplex PCR is suitable for detecting malarial infection from endemic areas whose cases may have low parasitemia and/or mixed infection. The factors significantly related to malarial infection from 260 questionnaires were: (1) children and young adults, (2) not having lived in the area more than 5 years, and (3) not using a mosquito net over the bed, indicating an increased risk of new residents of contracting malaria and a need to promote bed nets.     

Epidemiological study of blood lead levels of children and adolescents living in Campania, Italy.

The aim of the present study is to evaluate blood levels (PbB) in a group of 500 (245 M, 255 F) children and adolescents of Campania (Italy) aged from 0.197 to 16.915 years, 269 (136 M, 133 F) of whom lived in urban zones and 231 (109 M, 122 F) in rural zones. PbB was assayed by electrothermal atomic absorption spectroscopy. The parents of the examined subjects children were interviewed about common risk factors for lead exposure using a standardized questionnaire. The PbB of children living in urban zones were significantly higher than the PbB of those living in rural zones (60.0 +/- 3.0 mg/L vs. 40.0 +/- 2.0 mg/L, p < 0.001). A PbB higher than 100 mg/L was found in 27 children (5.4%). We observed a significant correlation between age and PbB (p < 0.001, r = 0.529). Our data regarding children and adolescents demonstrate that the prevalence of PbB higher than 100 mg/L is greater in children living in urban areas (6.89%) than in subjects living in rural areas (3.89%). The findings can be explained by the higher presence of risk factors of Pb exposure in urban areas. Our data, if compared with those of previous studies concerning children of Campania, show a clear decrease of PbB. The correlation that we found between age and PbB indicates that long-term exposure at low doses more than a more intensive but short-term exposure seems to be important for the increase of blood lead levels.     

Serological Survey of Paracoccidioidomycosis in Cats

The objective of the present study was to evaluate infection of cats by Paracoccidioides brasiliensis. Serum samples of 136 cats from rural (n = 86) and urban areas (n = 50) were analyzed by indirect ELISA and immunodiffusion test using P. brasiliensis gp43 and exoantigen as antigens, respectively, and an overall reactivity of 31.6 % was observed by ELISA although no reactivity was detected by immunodiffusion. The positivity observed in animals living in rural areas (48.8 %) with free access to soil was significantly higher (P < 0.0001) than among urban animals (2 %) with limited access to soil, although no significant difference was observed in relation to age or sex. The high rates of positivity observed in cats from rural areas suggest that not diagnosed cases of this mycosis may be occurring in cats living in endemic areas for human paracoccidioidomycosis. This is the first report showing serological evidence of P. brasiliensis infection in cats.     

Diphtheria morbidity in Russia today

The data on diphtheria morbidity and the occurrence of carrier state for its causative agent at the period of 2001-2002 were analyzed. The rates of morbidity and detected carrier state for these years were 0.63-0.55 and 0.65-0.64 respectively. Nevertheless, in spite of the relatively low morbidity rates the presence of the toxic forms of diphtheria (400 patients for two years) and lethal cases (with lethality rate reaching 5.4%) indicated that the epidemic situation in diphtheria remained tense. The most unfavorable situation was observed in the North-Western and Central regions of Russia. In urban areas morbidity rates were still 2- to 3-fold higher in than in rural ones, but the latter showed a higher percentage of severe cases (46.6% in 2001 and 39.7% in 2002) and lethal outcomes (13.6% and 19.2%). The latter was indicative of drawbacks in the immunoprophylaxis, diagnostics and treatment of diphtheria in rural areas. In the total structure of diphtheria patients adults prevailed: 75%. The highest morbidity rates were registered among children aged 3-6 years, among adults in the age groups of 18-19 years and 50-59 years. The epidemic process developed mainly among the immunized population, which was indicated by a high proportion of vaccinated persons among those affected by this infection (62.8-66.6%) and a mild course of the disease in the majority of them. The present epidemiological situation in diphtheria was determined by patients not vaccinated against this infection. The proportion of severe cases among nonvaccinated children was 42.4-51.6% and lethal outcomes, 12.9-15.1%. Among nonimmunized adults these figures were equal to 43.1% and 9.3% respectively. The highest percentage of children, not vaccinated during the first years of their life, was registered among those in the asocial families, refugees and homeless persons. Among adults these were persons above 50 years old, as well as jobless persons of working age, pensioners and invalids, who had limited possibilities of undergoing vaccination due to their social position. It was these social and age groups that should be regarded as risk groups with respect to the severity of the course of diphtheria and lethality. To stabilize diphtheria morbidity, the full complex of prophylactic and antiepidemic measures, and primarily the immunization of the population, should be systematically carried out.     

大连地区人群肠道寄生虫感染调查及流行病学分析

于2002年9～12月采用改良加腾氏法等方法对大连地区人群肠道寄生虫感染开展调查并对此进行流行病学分析。调查结果显示,在被检的10865人群中,肠道寄生虫总感染率为4．38％(重76／10 865),三个片区人群感染率分别为城市2．82％、郊区4．60％和区县7．79％;男性与女性所感染的寄生虫种类及感染率有所差异;在我们所检查出的寄生虫中主要是蛔虫,其次为鞭虫;农民肠道寄生虫感染率最高(6．89％),其次是小学生(4．75％)。本次调查结果表明,大连地区人群肠道寄生虫的感染情况已得到有效的控制．并且感染率呈明显下降趋势。     

Different patterns of intestinal helminth infection among young workers in urban and rural areas of Alexandria Governorate, Egypt.

The process of urbanisation taking place in most developing countries is creating favourable conditions for an increase in prevalence of infections, especially with intestinal parasites, in the marginal areas of the towns. The present study was implemented in 1996 to assess the varying prevalence and intensity of infection among young workers in urban and rural areas of the same Governorate (Alexandria, Egypt). The sample comprised 408 male subjects, 8 to 19 years of age, in various occupations: 308 from urban areas, 67 from an industrialised village close to the desert, and 33 from a rural village. A quantitative diagnosis of intestinal helminth infections was made using the Kato-Katz technique, with a double reading of each slide. The results showed a higher prevalence (> 50%) and intensity of infection (indirectly measured as number of eggs per gram of faeces) than in previous studies. Furthermore, a higher prevalence and intensity of infection with Ascaris lumbricoides and Trichuris trichiura was detected in urban districts, as compared to rural areas. This difference was statistically significant. High crowding index, latrine shared with other families and no piped water inside the household, were more common in urban areas as compared with rural settlements and also associated with a higher intensity of infection by soil-transmitted helminths. The trend toward urbanisation seems to have caused deterioration of living conditions and sanitation standards in some areas of Alexandria city, with the most vulnerable people experiencing an increase in intestinal parasitic infections.     

A survey of Enterobius vermicularis infection among children on western and southern coastal islands of the Republic of Korea

To determine the status of Enterobius vermicularis infection among children living on western and southern coastal islands of the Republic of Korea, children (3-10 years) in 39 kindergartens and primary schools were examined using the cello-tape anal swab method, during July and August 2000. Of 1,661 children examined, 307 (18.5%) were found to be positive for E. vermicularis eggs. The highest infection rate (59.3%) was found in a kindergarten and a branch school of Shinyang primary school on Chujado, Jeju-do (Province). Remarkable differences in egg positive rates were observed in different localities. The egg positive rate for boys (21.3%) was significantly higher than that of girls (15.4%) (P = 0.02). However, positive rates were not significantly dependent on age. The results of the present study show that E. vermicularis infection is highly prevalent among pre-school and primary school children living on the western and southern coastal islands of the Republic of Korea, and indicate the need for efforts to control this infection.     

Parasitic infections, anemia and malnutrition among rural settled and mobile pastoralist mothers and their children in Chad

Malnutrition, resulting from various etiologies, is common in rural Chadian women and children. This cross-sectional study assessed the spectrum of parasitic infection and level of anemia and their effect on nutritional status in settled and mobile pastoral mothers and children near Lake Chad. Intestinal parasites were evaluated using direct fecal smears and the Kato-Katz technique. Malaria status was determined using Paracheck-Pf(?) rapid diagnostic test, and anemia was assessed with the Hemocue photometer. Nutritional status was evaluated using anthropometric parameters. At the end of the 2008 wet season, the prevalence of malnutrition was 36% [confidence interval (CI) 30-42] among women and 15% (CI 11-18) among children. The prevalence of intestinal parasitic infection was 75% (CI 68-83) among women and 60% (CI 53-66) among children. The predominant helminth species was Ascaris lumbricoides while Entamoeba histolytica/dispar was the most common protozoan. The hookworm prevalence was 14% (CI 8-20) in women and 18% (CI 13-23) in children. Malaria prevalence was low among women (1%, CI 0.5-2) and children (3% CI 2-5). No significant difference was observed in the prevalence of parasitic infection between the mobile pastoralist and rural sedentary populations. Thirty-four percent (CI 27-40) of nonpregnant women, 53% (CI 34-72) of pregnant women, and 27% (CI 23-32) of children were anemic. In subjects infected with Plasmodium, all women and 54% (CI 22-85) of children were anemic. Malnutrition was significantly associated with anemia in mothers and with selected intestinal parasites, anemia and age in their children.     

Malaria transmission in a central area of Futa Djalon (Guinea): results of a parasitological survey during the 1989 rainy season.

A malaria survey based on household surveys and dispensary visits without notice was carried out during the rainy season of 1989 in three selected areas of central Futa Djalon (Republic of Guinea). Preliminary entomological evidence showed that Anopheles gambiae was the main vector in the area with a CS positive rate of 7.6% and a human blood index of 78% in August 1989. Indoor resting densities were highest in the rural village, lowest in Labé and intermediate in the town of Timbi Madina (median density per room of 18, 2 and 4.5, respectively). The household survey showed different parasite rates in the three areas: 78.2% of children had parasitaemia in Sombili, 45.8% in Timbi Madina and 16.7% in the urban sector of Labé. Prevalence and levels of P. falciparum antisporozoite antibodies were lowest in the urban area (seroprevalence of 51.9% and median titre of 2.4 arbitrary units), intermediate in the town (70.1% and 5.2) and highest in the rural village (78.9% and 5.8). Serological findings produced by dispensary visits were similar to those obtained with the household surveys except in the rural area, while parasitological data obtained with the two sampling methods were different both in rural and in urban areas. Routine malaria diagnosis made on a presumptive basis in the health services in the survey period was able to detect 30.1% of cases with parasitaemia and 53.2% of cases with hyperparasitaemia (sensitivity) and malaria was correctly not suspected in 82.8% of non parasitized people (specificity).