Potential for Transmission of Schistosomiasis in Kayonza District

Introduction: Schistosomiasis; also known as bilharzia or snail fever; is a tropical parasitic disease caused by a trematode platyhelminthes called Schistosoma check for this species in other resources sp. Schistosoma species are transmitted by cercariae penetrating the skin when a person is bathing; washing clothes; fishing or engaged in agricultural activities; involving contact with fresh water that has fecal or urinary contamination; and contains the parasites' snail host. The present study aimed to survey freshwater snails in Kayonza District (Rwanda) especially Lake Muhazi and surrounding water bodies; stream and swamps to assess the potential for transmission of two species of Schistosoma: S. mansoni check for this species in other resources and S. haematobium check for this species in other resources. Methods: Six sites were selected to assess the potential for transmission of schistosomiasis. The intermediate hosts of schistosomes; namely the snails Biomphalaria check for this species in other resources ; Bulinus check for this species in other resources sp. and Lymnaea check for this species in other resources sp.; were collected and brought to the laboratory and investigated to see if trematode cercaria responsible for the disease were present. Results: Snails dissected were not only infected with trematode cercaria but also with annelids and flatworms (Platyhelminths). Cercaria found therein were of two types: furcocercous; probably responsible for schistosomiasis; and gymnocephalous cercaria for fasciolasis: an infection of cattle; goats and sheep. Conclusion: Biomphalaria sp were the major hosts for schistosome cercaria; and most snails collected of this species were infected. Moreover; they were found in large number from all sites. Lymnaea sp; hosts snails for Fasciola cercaria check for this species in other resources ; were also found in a considerable number compared to the low number of Bulinus sp in the region. District and national authorities may wish to further investigate this infestation and identify potential interventions to disrupt the disease transmission

Relationship of daytime asthma symptom frequency to morning peak expiratory flow.

Since management plans based on peak flow measurements are increasingly used, the relationship between peak flow rate and ensuing symptom frequency is of particular interest to the treatment of asthma. The objective of this study was to examine to what extent morning peak flow was related to symptom frequency during the day. In 168 out of 307 randomly selected adult asthmatics from a general practice population, adequate recordings of morning peak flow (amPF) and symptom frequency during the day (DSF) were obtained for 28 days. In each individual, the relationship between these two variables was studied and the mean values of these two variables over 28 days were calculated. The relationship between the means of the variables was also examined for the group as a whole. In individuals, the correlation between amPF and DSF varied widely; only 16% of patients had a good relationship (Pearson r = -1 to -0.5). For the whole group, the relationship between mean amPF and mean DSF best fitted a curvilinear model (r = -0.6). This was unaffected by age, sex or the use of inhaled steroids. For the majority of asthmatics, morning peak flow may be an unreliable predictor of expected symptoms during that day. Reliance on peak flow measurement as a tool enabling asthmatics to manage their asthma on a daily basis needs to be reconsidered.

Intestinal helminth infections in rural school children in Njala, Sierra Leone.

In a survey of five primary schools and one secondary school in and around the Njala University College environment, in Southern Sierra Leone, 1820 school children were examined. Ascaris lumbricoides was the most common helminth encountered (33.3%) followed by Trichuris trichiura (14.6%) and hookworm infection (10.4%). There was striking differences in the rate of infection between the various schools with the International School being the least affected by all parasites. Multiple infections were quite common, with 53.1% having one type of helminth infection, 40% had two types of helminth infections, while 6.9% had three or more helminth infections. School screening should be an important component of Primary Health Care in Sierra Leone since it offers good opportunity for disease surveillance, health education and early detection and treatment of infections before they become chronic.

Why are hospital admission and mortality rates for childhood asthma higher in New Zealand than in the United Kingdom?

New Zealand has higher mortality and hospital admission rates for asthma than England and Wales. To determine the reasons for this the available data on asthma mortality and hospital admissions from the Auckland region of New Zealand were compared with data from the South West Thames Region of England for 1979-86 and data from previous surveys on prevalence of wheeze (Auckland 1985, Croydon 1978). In addition, a survey of general practitioners was carried out to determine their approach to the management of asthma, patient simulations being used. Asthma mortality in children of European descent aged 5-14 years was 2.5 times higher in Auckland than in South West Thames. The reported lifetime, 12 month, and one month prevalences of wheeze were also higher in Auckland (by 18.5%, 32.1%, and 87.5%). Unexpectedly, the hospital admission rate for asthma in children of European descent aged 5-14 years was 5% less in Auckland than in South West Thames. Comparative studies of hospital case notes and of the replies from general practitioners showed that in Auckland the duration of illness before admission was greater and that general practitioners were less likely to admit patients with acute asthma. The overall standard of general practitioner care in Auckland was, if anything, higher than in South West Thames but in both areas there was considerable variation. On balance it was concluded that the higher mortality rate in New Zealand is explained by higher levels of morbidity rather than relative deficiencies in care. Nevertheless, the implications of the lesser use of hospital care for acute asthma observed in Auckland need further consideration.

Parasitologic survey of Onchocerca volvulus infection in the Nimiyama Chiefdom, Kono District, Sierra Leone.

Infection due to Onchocerca volvulus was investigated in the Nimiyama Chiefdom, Kono District, Sierra Leone, where Simulium damnosum s.l. is known to breed but no data on the prevalence and intensity of O. volvulus infection exists. Of the 735 individuals sampled by the skin snip method in five villages, 471 (64%) were infected. The infection rate for males was significantly (p less than 0.05) higher than that of the females. Two hundred and ninety-one (70.0%) of the 416 males skin snipped and 180 (56.0%) of the 323 of their female cohorts were infected. The intensity of infection increased with age, with the younger cohorts presenting lower microfilarial density (MFD). Palpable nodules were observed in 230 (48.4%) of individuals found positive for skin microfilariae and in 37 (5.0%) individuals found negative for skin microfilariae. It is concluded that O. volvulus infection is mesoendemic in the Nimiyama Chiefdom, with the intensity of infection increasing with age.

Randomized controlled trial of small group education on the outcome of chronic asthma in general practice.

The effectiveness of small group education of general practitioners in the management of asthma was evaluated by randomized controlled trial. The outcome measure was the asthma morbidity of the general practitioners' own patients. Following random selection from the list of one family practitioner committee in suburban London, the 27 participating general practitioners were allocated randomly to one of two educational groups or to a control group. The educational intervention comprised eight meetings at which the management of chronic asthma was discussed and attempts made to devise agreed strategies for care. The two educational groups devised different strategies. Asthma morbidity was assessed by postal questionnaires to patients before the intervention and on five further occasions at six-monthly intervals over two and a half years. Of 454 patients who entered the study 338 completed the sixth and final assessment. The degree of morbidity experienced by the patients and their reported use of asthma specific drugs was considerable and was notably constant over the period of study. There was no difference in morbidity between the three groups at the outset and no effect of the intervention could be demonstrated. In this educational intervention the participating general practitioners were not informed about the morbidity and drug use reported by their patients. This information may be crucial if small groups are to be used to design and implement effective strategies for care. It would appear that small group education of general practitioners in the form reported here is not effective in reducing morbidity from chronic asthma.

Swamp rice development, schistosomiasis, and onchocerciasis in Southeast Sierra Leone.

Seventy-four villages in eastern Sierra Leone, West Africa, many having a recently developed rice swamp, were surveyed for the presence of schistosomiasis and onchocerciasis, and their vectors. Prevalence rates for Schistosoma haematobium and S. mansoni were low, although the infections were widespread. There is some evidence that S. mansoni is extending its range in Sierra Leone although this is problematical because of the apparent absence of Biomphalaria pfeifferi, the recognized snail vector, from areas where the disease now occurs. The characteristics of rice swamp environment now being created in Sierra Leone are described and results of snail collections, which were with few exceptions small, are presented. Reasons for the apparent unsuitability of the developed rice swamp as a snail habitat are discussed. Onchocerciasis was found in all villages and the prevalence rate, almost 50%, was high. The rice swamp is not a suitable breeding site for Simulium damnosum s.l., but the study area is crossed by several major rivers and all villages in the area are within flying distance of potential breeding sites. There was no positive evidence that expansion of swamp rice farming will increase the incidence of water based/related diseases but a control program for onchocerciasis, which is a major rural health problem, would seem to be a national priority.

Serum enzyme activities in the African elephant (loxodonta africana).

The serum activities of aspartate aminotransferase, alanine aminotransferase, alpha-hydroxybutyrate dehydrogenase and creatine phosphokinase have been measured in the African elephant. In general, the values were broadly comparable with those of man except that alanine aminotransferase was much lower and creatine phosphokinase higher. No variation due to age, sex, season or location was observed.