Effect of a malaria suppression program on the incidence of African Burkitt's lymphoma.

From 1977 to 1982, the authors attempted a malaria suppression trial in North Mara District, Tanzania, to see whether the incidence of Burkitt's lymphoma (BL) could be lowered by reducing the level of malarial infection in a child population below 10 years of age. Immediately after initiation of the suppression trial, the prevalence of malaria fell drastically in the Mara children; however, soon after, the rate of malarial infection rose again in the trial area in spite of continued chloroquine distribution, and by 1981 the prevalence of malarial infection again reached the high levels that had prevailed in the North Mara lowlands before 1977. However, during the period of chloroquine distribution in North Mara, the level of malarial infection there was constantly lower than that observed in a comparison area in South Mara, although the two areas had been similar with respect to malaria endemicity prior to the intervention.

Serial studies on the evolution of chloroquine resistance in an area of East Africa receiving intermittent malaria chemosuppression.

Serial in vitro and in vivo tests for chloroquine sensitivity of Plasmodium falciparum were carried out from 1979 to 1982 in an area of E. Africa where chemosuppression with chloroquine had been attempted since 1977. Within 1(1/2) years there were signs of a decreasing drug response.

The reliability of questionnaire-derived historical dietary information and temporal stability of food habits in individuals.

Thirty-four males and 45 females who participated in household surveys 15 or 25 years earlier in rural Denmark were interviewed in 1982 about present and past food habits. Comparison of the information from the survey and the two interviews indicates that recall of past diet is strongly influenced by present dietary habits. As the relative classification of individuals according to their food habits appears to have changed little over time, information on current diet, perhaps supplemented by information on particular changes, can provide useful classification of individuals for epidemiologic purposes.

Endemic Kaposi's sarcoma: incidence and risk factors in the West Nile District of Uganda.

Out of 72 Kaposi's sarcoma patients diagnosed between 1951 and March 1976 at Kuluva Hospital, West Nile District, Uganda, 64 with known co-ordinates were plotted on a map. Sixty-two of these were noted to live at an altitude of 853 metres or more (greater than or equal to 2,800 feet). Twenty-four patients were thought to be still alive and visits were made to their homes.

Epstein-Barr virus markers in a series of Burkitt's lymphomas from the West Nile District, Uganda.

In an epidemiological survey in the West Nile District of Uganda, 70 pathologically confirmed BL cases were detected over a 5-yr period; this corresponded to an annual incidence rate of 1.6 per 100,000 general population or about 5 per 100,000 children in the age group 5-14 yr. Of the confirmed cases which were examined by EBV/DNA molecular hybridization, 96% were found to contain an average of 38 EBV genome equivalents per tumour cell, whereas none of the examined unconfirmed cases did.

Final case reporting from the Ugandan prospective study of the relationship between EBV and Burkitt's lymphoma.

A prospective epidemiological study was carried out in the West Nile District of Uganda from 1972 to 1979 in order to investigate the aetiological role of the Epstein-Barr virus (EBV) in Burkitt's lymphoma (BL). By 1976, fourteen BL cases had been detected among the 42,000 children originally bled in the study area. Testing of sera from BL candidates and neighbourhood controls showed that children who develop BL later have EBV/VCA titres several dilutions higher than their age- and sex-matched neighbours.

Transcapillary and interstitial diffusion of Na-fluorescein in chronic venous insufficiency with white atrophy.

White atrophy (atrophie blanche) in the medial ankle region due to chronic venous insufficiency (stasis syndrome) was studied in 12 patients by fluorescence video microscopy [1,8]. After intravenous bolus injection of 1 ml of 20% Na-fluorescein the dynamic phenomena of transcapillary and interstitial diffusion of the dye were analyzed by a videodensitometer which has moved on single frames of the TV-recordings across white atrophy at different times after dye appearance. White atrophy is characterized by 3 main areas: 1) the avascular field sensu strictu, 2) the border region with enlarged and tortuous capillary loops, and 3) the more remote capillaries showing less altered morphology.

The frequency of Epstein-Barr virus infection and Burkitt's lymphoma at high and low altitudes in East Africa.

Burkitt's lymphomas (BL) is frequent in the tropical lowland of Africa but rare--even in the tropics--at altitudes higher than 5,000 feet above sea level. Serological surveys were carried out in Uganda and Tanzania to see whether the variation in BL incidence from high to low areas is paralleled by a variation in the extent of infection with the putative Epstein-Barr virus. Sera were collected from samples of the general child population living at high and low altitudes in the West Nile District in Uganda and in North Mara, Tanzania.

Space-time clustering of Burkitt's lymphoma in East Africa: analysis of recent data and a new look at old data.

Forty cases of Burkitts' lymphoma (BL) in North Mara, Tanzania, with onset between 1971 and 1977, were analysed for evidence of space-time clustering. Previous analyses in East Africa had produced conflicting results. The Knox method used in those analyses dichotomizes the space and time scales and does not take into account the degree of closeness.

Further studies of antibody levels to Herpes simplex virus, cytomegalovirus, measles virus, and adenovirus type 5 in Burkitt's lymphoma patients.

Sera collected from Burkitt's lymphoma (BL) patients before and after tumor manifestation were tested for antibodies to herpes simplex virus (HSV), cytomegalovirus (CMV), measles virus (MV) and adenovirus type 5, using the immunofluorescent (IF) techniques in all instances except for MV where complement fixation (CF) was used. It was found that none of these viruses showed higher antibody levels in BL patients than in controls, either before or after the appearance of the tumor. The patients came from the West Nile District of Uganda.

Epidemiological evidence for causal relationship between Epstein-Barr virus and Burkitt's lymphoma from Ugandan prospective study.

Results from a prospective sero-epidemiological study initiated in Uganda in 1971 indicate that children with high antibody titres to Epstein-Barr virus structural antigens are at high risk of developing Burkitt's lymphoma. These findings strongly support a causal relationship between the Epstein-Barr virus and Burkitt's lymphoma but suggest that the oncogenic potential of the virus is realised only in exceptional circumstances.

Environmental factors in the etiology of nasopharyngeal carcinoma: report on a case-control study in Hong Kong.

A case-control study was undertaken of Cantonese NPC patients hospitalized in the Queen Elizabeth Hospital, Hong Kong. One age- and sex-matched control was selected for each NPC case from hospitalized patients with cancers other than NPC. A total of 150 NPC patients and 150 controls were interviewed in order to compare the two groups with respect to socio-economic status, dietary habits and health status.

Space-time clustering of Burkitt's lymphoma in the West Nile district of Uganda: 1961-1975.

Epidemiological data relating to all 202 patients diagnosed with Burkitt's Lymphoma (BL) in the West Nile District of Uganda in the period 1961 to 1975 have been reviewed and analysed. Statistically significant evidence of space-time clustering of cases, first reported for the period 1961-65, was also present during 1972-73, but not during other periods. The patients involved in such clusters were found to be older than other patients (P less than 0.

[Prospective epidemiologic studies and the nature of the association between Epstein-Barr virus (EBV) and Burkitt's lymphoma (BL)].

The prospective study carried out by the International Agency for Research on Cancer on the relationships between E.B.V.

Sero-epidemiology of the Epstein-Barr virus: preliminary analysis of an international study - a review.

Samples of Chinese, Indian, African and Caucasian populations, randomly selected in Hong Kong, Singapore, the West Nile District of Uganda, and Nancy, France, were titrated for antibodies to EBV, viral capsid (VCA) and complement-fixing soluble (CF/S) antigens. The age-specific prevalence of infection (as reflected by the proportion of VCA-positive individuals) varied greatly up to the age of 10 years in the four populations studied, the West Nile District of Uganda being outstanding in having an early and massive infection rate. Differences were also observed between ethnic groups in Singapore, where the Chinese appeared to have a delayed infection rate compared to the Indians.

The variability in immunofluorescent viral capsid antigen antibody tests in population surveys of Epstein-Barr virus infections.

A comparative study of the extent of Epstein-Barr virus (EBV) infections in populations that differ with respect to the incidence of tumours associated with this virus is now in progress in different countries. In these surveys of antibody titres from the various study populations, it is of critical importance that strict comparability be maintained. Despite standardization of techniques and reagents in the cooperating laboratories, considerable variation in the results has remained.