[Health of foreign students - representatives of diasporas as a social problem].

The article is devoted to the analysis of modern approaches to the problem of the health of foreign students who are educational migrants and need medical care, taking into account their current social status and status in the territory of the Russian Federation. The undermining of health, significant psycho-emotional tension and, in general, worries about maintaining health can affect the learning process, therefore it is necessary to determine in whose area of responsibility the health of educational migrants is: whether they themselves are obliged to monitor their condition and organize medical care, whether the university should participate in the organization of medical commissions and examinations, or diasporas, whose members are often foreign students, may have these powers.

Identification of novel virus-specific antigens by CD4⁺ and CD8⁺ T cells from asymptomatic HSV-2 seropositive and seronegative donors.

Reactivation of latent herpes simplex virus 2 (HSV-2) infections can be characterized by episodic recurrent genital lesions and/or viral shedding. We hypothesize that infected (HSV-2(pos)) asymptomatic individuals have acquired T cell responses to specific HSV-2 antigen(s) that may be an important factor in controlling their recurrent disease symptoms. Our proteomic screening technology, ATLAS, was used to characterize the antigenic repertoire of T cell responses in infected (HSV-2(pos)) and virus-exposed seronegative (HSV-2(neg)) subjects. T cell responses, determined by IFN-γ secretion, were generated to gL, UL2, UL11, UL21, ICP4, ICP0, ICP47 and UL40 with greater magnitude and/or frequency among cohorts of exposed HSV-2(neg) or asymptomatic HSV-2(pos) individuals, compared to symptomatic recurrent HSV-2(pos) subjects. T cell antigens recognized preferentially among individuals who are resistant to infection or who are infected and have mild or no clinical disease may provide new targets for the design of vaccines aimed at treating and/or preventing HSV-2 infection.

Thermoregulatory efficiency is increased after heat acclimation in tropical natives.

To evaluate the effects of heat acclimation on sweat rate redistribution and thermodynamic parameters, 9 tropical native volunteers were submitted to 11 days of exercise-heat exposures (40+/-0 degrees C and 45.1+/-0.2% relative humidity). Sudomotor function was evaluated by measuring total and local (forehead, chest, arm, forearm, and thigh) sweat rates, local sweat sodium concentration, and mean skin and rectal temperatures. We also calculated heat production (H), heat storage (S), heat exchange by radiation (R) and by convection (C), evaporated sweat (E(sw)), sweating efficiency (eta(sw)), skin wettedness (w(sk)), and the ratio between the heat storage and the sum of heat production and heat gains by radiation and convection (S/(H+R+C)). The heat acclimation increased the whole-body sweat rate and reduced the mean skin temperature. There were changes in the local sweat rate patterns: on the arm, forearm, and thigh it increased significantly from day 1 to day 11 (all p<0.05) and the sweat rates from the forehead and the chest showed a small nonsignificant increase (p=0.34 and 0.17, respectively). The relative increase of local sweat rates on day 11 was not different among the sites; however, when comparing the limbs (arm, forearm, and thigh) with the trunk (forehead and chest), there was a significant higher increase in the limbs (32+/-5%) in comparison to the trunk (11+/-2%, p=0.001). After the heat acclimation period we observed higher w(sk) and E(sw) and reduced S/(H+R+C), meaning greater thermoregulatory efficiency. The increase in the limb sweat rate, but not the increase in the trunk sweat rate, correlated with the increased w(sk), E(sw), and reduced S/(H+R+C) (p<0.05 to all). Altogether, it can be concluded that heat acclimation increased the limbs' sweat rates in tropical natives and that this increase led to increased loss of heat through evaporation of sweat and this higher sweat evaporation was related to higher thermoregulatory efficiency.

Comparison of safety of glucose oral rehydration solution and maize oral rehydration therapy for home management of diarrhoea in Kenya.

Safety margins and variability in the composition of glucose and maize-based oral rehydration therapy (ORT) prepared by mothers in a rural district of Western Kenya, are reported here. In a 2-year longitudinal field study, packets containing glucose ORS and a home solution made with maize and table salts, were provided to the mothers of 6180 children in Kakamega District in two separate sub-locations. Experienced and trained field workers supported by community registered nurses provided training for the preparation and use of ORT during weekly visits to every household. On four occasions separated by 4-6 months, a 5 per cent random sampling was done of the home-prepared solutions actually used for the treatment of children with diarrhoea. The water used for preparing ORT was also sampled. Samples of 174 glucose-based ORT, 148 maize-salt ORT, and 201 samples of water were analysed. Only 2 per cent of the maize-based ORT were above 120 meq/1 sodium (i.e., the safe range of sodium concentration) compared to 17.8 per cent for glucose solutions (p < 0.001). Home water samples contained substantial amounts of salt, which could unpredictably affect the final composition of the ORT solutions. We conclude that maize-salt ORT had a better margin of safety than glucose-based ORS.

Risk factors for invasive cervical cancer in Kenyan women.

BACKGROUND: Few epidemiological investigations of invasive cervical cancer have been conducted in Sub-Saharan African populations. METHODS: Using information collected as part of the hospital-based World Health Organization (WHO) Collaborative Study of Neoplasia and Steroid Contraceptives, we examined potential risk factors for invasive cervical cancer among Kenyan women. In all 112 women with histologically confirmed invasive cervical cancer diagnosed at the Kenyatta National Hospital, Nairobi, Kenya, between June 1981 and September 1988 and 749 control subjects were included in the present analyses. All women were interviewed regarding their medical and reproductive history, methods of birth control, and history of sexual relationships and sexually transmitted infections. Multiple logistic regression procedures were used to derive maximum likelihood estimates of adjusted odds ratios (OR) and 95% confidence intervals (CI). RESULTS: After adjusting for age, several factors were found to be associated with invasive cervical cancer. These include multiple sexual partners, early age at first sexual intercourse (OR = 1.9 and 2.6 for women reporting first intercourse at age 16-17 years and < 15 years, respectively, compared to women with first intercourse > or = 18 years), history of abnormal vaginal discharge (OR = 13.8, 95% CI: 8.3-23.0), and history of gonorrhoeal infection (OR = 3.2, 95% CI: 1.6-6.2). Low educational attainment and multiparity were also associated with the risk of invasive cervical cancer. Although the Papanicolaou smear has been extensively used as a screening method for cervical cancer in many countries, only three cases and four controls reported ever having a Papanicolaou smear (2.6% cases and 0.5% of controls). CONCLUSIONS: As has been observed in other parts of the world, cervical neoplasia in Kenya appears to be a late consequence of venereally transmitted carcinogenic agents.

Comparative aetiology of childhood diarrhoea in Kakamega and Kiambu Districts, Kenya.

Two hundred diarrhoea specimens collected during January to February 1988, from rural children aged 0 to 60 months in Kakamega District were examined for bacteria, parasites and rotavirus. The results were compared with a sample of 184 diarrhoea specimens matched for month of collection, taken from data collected in the same manner from children in Kiambu District. The mean ages of children in the 2 samples did not differ significantly. There were significant differences in the prevalence of specific potential pathogens isolated in the 2 areas. Notably, A. lumbricoides and rotavirus were more common in Kakamega, while G. lamblia, Entamoeba histolytica, Trichomonas hominis, Cryptosporidium sp., Hymenolepis nana and EPEC were more common in Kiambu. There was no difference with respect to prevalence of Campylobacter sp. or Blastocystis hominis. Factors which were probably important in determining aetiological differences included climate, water sources, animal contact and crowding. The differences highlight the fact that general predictions about aetiology cannot be made from isolated studies.

PIP: A total of 200 loose or watery specimens of diarrhea collected during January and February 1988 from rural children aged 0 to 60 months (mean age of 17.9 months) in Kakamega District, Kenya, were examined for bacteria, parasites, and rotavirus. The results were compared with data from a sample of 184 diarrhea specimens collected during January and February 1986, in the same manner from children with a mean age of 19.7 months in Kaimbu District. Complete investigations were accomplished in 140 of 184 specimens in the Kiambu sample. The most common organism in the Kakamega sample was A. lumbricoides (31%) compared with Escherichia coli (EPEC, 26.4%) and G. lamblia and (26.1%) in the Kiambu sample. There was no Cryptosporidium or Hymenolepis nana isolated in the Kakamega sample, while their frequencies were 2.7% and 3.8%, respectively, in the Kiambu sample. A. lumbricoides and rotavirus were significantly more common in the Kakamega sample, while all the protozoa, including G. lamblia, Entamoeba histolytica, and Trichomonas hominis, were more commonly isolated in the Kiambu ample. The Kiambu sample involved significantly more persistent diarrheas: more than 8 days (18.8%) than the Kakamega sample (3.5%) (p 0.001). A total of 44/140 (31.4%) of diarrheas were negative for potential pathogens in the Kiambu sample compared with 67/200 (33.5%) in the Kakamega sample. Mixed infections were common in both samples in which pathogens were isolated, with 53/133 (39.8%) in Kakamega being mixed, compared with 51/96 (53.1%) in Kiambu. One specimen in Kakamega had 5 potential pathogens (rotavirus, EPEC, C. lamblia, A. lumbricoides, B. hominis), while 1 specimen in Kiambu harbored 7 (EPEC, Shigella, Campylobacter, E. histolytica, T. hominis, G. lamblia, B. hominis). The community etiology of childhood diarrhea appears to be influenced by many factors which encourage direct fecal-oral transmission including climate, water sources, animal contact, and crowding.

Assessment of epidemiological and HIV/AIDS publications in Africa.

To assess the quantity of epidemiological publications emanating from Africa, three international epidemiology journals were examined. In addition, a separate MEDLINE search was undertaken for 1987 and 1989-1990 to assess AIDS/HIV prevalence and incidence publications. Of 361 general epidemiological articles examined for 1974-1975, 49.3% were from the US, 20.5% from the UK, 11.1% from Europe, 10.2% from the rest of America, 4.4% from Asia, 3.9% from Australasia and 0.06% (only two) from Africa. The overall proportion from the USA declined to 44.0% by 1989-1990; from the UK to 11.1% while from South America and Australasia the proportion remained similar. Striking increases occurred in Europe and to a lesser extent in Asia. By 1989-1990 African articles contributed 3.6% (31) of the total. While over 90% of first authors came from the study region in the US, UK, Europe and Australasia; 85.7% in Asia; 70.8% in South America in 1989-1990, in Africa only 32.2% were authors from their continent. Of the 220 published articles on AIDS/HIV epidemiology 6.8% emanated from Africa in 1987 and 12% of 606 articles in 1989-1990. African scientists were first authors in 46.7% of articles from the continent in 1987 and only 35.5% in 1989 and 1990. In 1987, 60% of the articles were co-authored by overseas scientists of various nationalities while collaborative publications increased to 78.4% in 1989-1990. Only 15% of these articles were published in African Journals. This study stresses the urgent need for improving all aspects of epidemiological research and training in Africa with particular need with respect to AIDS/HIV research capacity.

Visceral leishmaniasis and malaria prevalence in West Pokot District, Kenya.

The prevalence of visceral leishmaniasis and malaria in the human population of West Pokot district of Kenya was studied in 1986. A total of 2139 people was proportionately screened for the two diseases according to four age categories (0-4, 5-14, 15-44 and greater than 45 years). Diagnostic methods included the enzyme linked immunosorbent assay (ELISA) and Leishmanin skin test for visceral leishmaniasis, and parasitological examination for malaria. The epidemiological value of the spleen rate was evaluated in relation to visceral leishmaniasis and malaria endemicity. A general decline of infection rates with altitude was observed for both diseases. Visceral leishmaniasis was less prevalent than malaria, with less than 2% active cases in any age group and had the same distribution in both sexes. Malaria infection rate was highest in the younger age groups, declining from 21.5% in the 0-4 year old age group to 5.5% in people more than 45 years old. Malaria affected significantly more males than females. The spleen rate was inappropriate for epidemiological survey of either malaria or visceral leishmaniasis due to an overlap in the distribution of the two diseases.

The dynamics of epidemiology and impact on the control of diseases: a review.

This paper describes the relationship between epidemiology and other desciplines including medical and social sciences both of which are expanding in scope. As a discipline, epidemiology is not only growing in scope as well but also developing new techniques of establishing facts about disease causation and interventions demonstrating how prevention programmes could be carried out for the benefit of communities from the burden of disease. Further, the effects of epidemiological findings in the developed North on the control of diseases and the lack of this in the poor South is described. The need for interdisciplinary approach in finding disease prevention solutions is emphasized.

Epidemiological and clinical aspects of oesophageal carcinoma in the USA.

A study was conducted of all primary oesophageal cancer cases hospitalized from 1970 to 1975 in Oklahoma City hospitals. During this 6 year period, 181 cases were identified. The average annual incidence in Oklahoma county was lowest in white females (2 per 100,000 population), and highest in black males (19 per 100,000 population). Some of the descriptive features of oesophageal carcinoma by age, sex and race distribution were largely compatible to those reported in the literature. Cases with carcinoma in which pain was the first symptom to appear, sought medical advice latest compared to cases with dysphagia as the first symptom, the latter group seeking medical advice earliest. Blacks and whites presented dissimilar distribution of tumours by site. Whereas in blacks 58% of carcinomas were located in the middle thoracic and none in the oesophagogastric junction, in whites tumours were more or less equally distributed in various anatomical sites. Black males exhibited higher mean ages at diagnosis in all sites than black females. The whites showed the opposite trend except in the oesophagogastric junction. Squamous cell carcinoma was the most frequent cell type (80%). The absence of adenocarcinoma cell types in blacks except only two male cases was a noteworthy observation. The clinical stage distribution by anatomical site was unusual for middle thoracic and gastric cardia carcinomas with 54% and 46% of tumours localized and in regional stages at diagnosis respectively.

Measles and mathematics: "control or eradication?".

A measles outbreak occurred in the Kirinyaga District in February, 1985. Immunization coverage against measles was above 80% in the district and increased by age. The immunization against measles was lowest (46%) in the age group (8-11) months and highest (90%) in the (36-59) months age group. However, the overall vaccine effectiveness in the childhood population (8-59) months was only 43.5% and peaked (91.5%) in the (24-35) months age group. Based on these and similar findings in some developed and developing countries the proposal for global measles eradication is suggestively premature and particularly so for the tropics. The eradication of measles poses far more substantial obstacles than did smallpox eradication. That transmission continues to occur in communities with very high measles vaccination coverage and high vaccine effectiveness (vaccine efficacy) is a true testimony to the difficulty involved.

Effects of steroidal contraceptives on gallbladder: a review.

In regard to gallbladder disease and oral contraceptive use, more than ten controlled epidemiologic studies have been reported and reviewed in this paper. The findings presented concerning the association of oral contraceptive use with the development of a gallbladder disease are contradictory. Oral contraceptive use and use of estrogens in postmenopausal women have been reported to be associated with increased attack-rates of a gallbladder disease, but the increased risk is found higher in those using estrogens than progestin based oral contraceptives. Other studies, however, have reported little overall effect of oral contraceptive use on the risk of the gallbladder disease. Where increased risk has been documented, this has been more related to duration than overall. The increased risk of oral contraceptive use to gallbladder disease has been observed higher in the 6-12 months of usage. Only one study has reported increased risk of gallbladder disease in long-term users. The increased gallbladder disease in oral contraceptive users may be greater in multiparae than in nulliparae; pregnancy and obesity may also pose an increased risk to the disease in oral contraceptive users. However, these findings are not widely accepted.

PIP: More than 10 controlled epidemiologic studies are reported and reviewed in this paper which examine gallbladder disease and oral contraceptive (OC) use. Findings concerning an association between the 2 are contradictory. OC use and the use of estrogens in postmenopausal women have been reported to be associated with increased attack rates of gallbladder disease, but the increased risk in higher in those women using estrogens than progestin-based OCs. Other studies, however, have reported little overall effect of OC use on the development of gallbladder disease. Where increased risk has been documented, it has been related more to duration. The increased risk of gallbladder disease related to OC use has been observed to be higher within the 6-12 month range of usage. Only 1 study reported increased risk of gallbladder disease in longterm users. The increase may be greater in multiparae than nulliparae; pregnancy and obesity may also pose an increased risk to the disease in OC users. However, these findings are not widely accepted.

Maize-salt solution in the treatment of diarrhoea.

In a block-randomized trial we compared the efficacy of citrate-containing glucose electrolyte solution (GES) versus maize-salt solution (MSS) in the treatment of children with mild and moderate diarrhoeal dehydration and acidosis. One hundred and fifteen children aged 3-59 months were entered in the study; 56 received GES and 59 MSS. Fifty-one (91%) of the 56 children given GES and 52 (88%) of the 59 children given MSS were successfully rehydrated with improvement in metabolic acidosis within 24 h. Initial hypokalemia in children treated with maize-salt solution was not corrected during the first 24 h of therapy. The children were, however, clinically asymptomatic after treatment. Carefully prepared maize-salt solution may be used successfully in mild and moderate dehydration in the home, as an alternative to the preferred glucose electrolyte formula.

Oral contraceptives use and liver tumours: a review.

Of the nine epidemiologic controlled studies reporting on the relationship between oral contraceptives use and hepatic tumours, three have findings specifically on the association of oral contraceptives use and hepatocellular adenomas. The strength of this association is reported to be dependent more on long-term oral contraceptive use. Three other studies have reported similar relationships of oral contraceptives use with hepatocellular carcinoma, whereas the remaining three other studies have reported no association between oral contraceptives use and hepatocellular carcinoma. There is however, an increased risk of hepatocellular carcinoma as the duration of oral contraceptives use increases. The risk of developing hepatocellular adenomas is higher in oral contraceptives users over 30 years of age than in the younger age groups. These tumours occur more often in oral contraceptive users taking pills with high doses of estrogens and progestogens; while they are not only associated with oral contraceptives containing mestranol, but also those containing ethinylestradiol.

Surveillance methodology for planning, and evaluation of nutritional states.

In developing countries in general, malnutrition has been widely reported as a major public health problem. Most of morbidity and mortality in these countries especially in the under fives are attributed to nutritional deficiencies at least in part. However, documentation of malnutritional problems in these countries is inadequate for monitoring, planning and coordination of control programmes. The data that is collected in few instances where this is accomplished is insufficient for a meaningful analysis. This paper suggests some simple epidemiological techniques which could be routinely employed using the existing health personnel to monitor and document temporal trends and types of data required for useful understanding of the problem.

Oral rehydration therapy and social marketing in rural Kenya.

In just a few years, oral rehydration therapy (ORT) has become the standard treatment to reduce infant diarrhoeal disease mortality in the developing world. The paper describes an ORT intervention campaign in a rural area in Western Kenya (Kakamega District). After about a year of careful preparation, the campaign was launched in January 1986 and compared the use of a value-added product (flavoured sachets) sold through private outlets in addition to primary care distribution of an unflavoured sachet in an experimental cell (Bukura Division). In a control cell (Novakholo Division), only unflavoured sachets were distributed free of charge through primary health care facilities. Using local perceptions of diarrhoeal disease management, the campaign in the experimental cell was carefully designed and mass communication techniques employed and adapted accordingly. Outcome assessments of the campaign, which lasted until March 1987, included the overall ORT utilisation over time. Changes in perceptions towards diarrhoeal disease management, direct assessments of mixing a 'safe and effective' solution accurately and other relevant process parameters were evaluated. Comparing several recent ORT intervention projects, the paper concludes that a combination of a commercial approach and mass communication techniques can further ORS use. If a proper incentive system for shopkeepers is installed and message design and ORS product are fully tailored to the perception and preferences of the target population, the commercial availability of ORS will create an extra demand of the product. However, this will not replace distribution of ORS salts delivered free of charge through primary care sources.

Cereal based oral rehydration solutions.

A total of 257 boys (age range 4-55 months), who had acute diarrhoea with moderate to severe dehydration, were randomly assigned to treatment with either the World Health Organisation/United Nations Childrens Fund (WHO/Unicef) recommended oral rehydration solution or cereal based oral rehydration solution made either of maize, millet, sorghum, or rice. After the initial rehydration was achieved patients were offered traditional weaning foods. Treatment with oral rehydration solution continued until diarrhoea stopped. Accurate intake and output was maintained throughout the study period. Efficacy of the treatment was compared between the different treatment groups in terms of intake of the solution, stool output, duration of diarrhoea after admission, and weight gain after 24, 48, and 72 hours, and after resolution of diarrhoea. Results suggest that all the cereal based solutions were as effective as glucose based standard oral rehydration solution in the treatment of diarrhoea.