The prevalence of diabetes in Central America was somewhat greater than in East Pakistan and Malaya, less
than in Uruguay and Venezuela, and substantially less than in affluent societies such as the United States. Differences in prevalence among Central American countries were modest but probably significant in some instances. In all Central American countries diabetes was more common in females but this difference was probably attributable to the greater adiposity of the women. Age-matched populations from eleven different countries of three continents have now been tested using standardized methods. Prevalence of diabetes varied greatly, and differences were more related to environment than to race. These results support the hypothesis that environmental factors can increase or reduce prevalence by several-fold.
The sensitivity and specificity of each of five screening tests were estimated in each of three to ten countries by testing subjects drawn from the general populations of adults over thirty-four years of age. This permitted comparisons among countries and among the different tests (fasting, postprandial, and postglucose urine tests, and fasting and postprandial blood glucose values). Sensitivity and specificity of each test varied widely among populations. For example, the sensitivity of the two-hour urine glucose ranged from 17 per cent in Nicaragua to 100 per cent in East Pakistan. Apparently specificity and sensitivity of such tests are influenced by many factors including both the circumstances under which the tests are performed and the characteristics of the population tested. It is, therefore, not possible to predict prevalence rates reliably by extrapolating from the results of screening tests. However, we believe the data for specific populations on the sensitivity and specificity of various tests will provide a rough guide in predicting the cost-effectiveness of alternative approaches to case detection in those particular countries. For instance, these results suggest that roughly 56 per cent of the occult diabetics in Costa Rica in this age group would be detected by a two-hour urine glucose, but only about 41 per cent of those in whom this test was positive would prove to have diabetes. Even modest changes of criteria in defining either "diabetes" or "abnormality" of the screening results produced marked changes in rates of sensitivity and specificity. With few exceptions, tests which were more sensitive were, comparably, less specific, and the reverse was also true. Rates of "diabetes" were markedly influenced by modest changes in diagnostic criteria.
279 cases of pulmonary tuberculosis were diagnosed during a 10 year period from 1969 to 1978. 60% as a result of self-referral and 40% from mass miniature radiography of the chest. For every case of pulmonary tuberculosis picked up, the number of MMRs required has been steadily rising from 1 in 1900 to 1 in 6700. Using South Korea study figures, it costs US$42600 for a case of pulmonary tuberculosis detected by MMR. Besides being not cost effective, there is little advantage in early detection with regard to prognosis, in preventing subsequent cases and in picking up other lung or cardiac abnormalities. Unnecessary radiation results from frequent MMR whose dosage is 10 or more times greater than standard chest X-rays. MMR should be limited to. contact tracing, prior to overseas courses and on termination of service.
Study site: medical boards submitted to Medical Directorate, Ministry of Defence, Malaysia
Screening by culture of endocervical specimens revealed four cases of gonorrhea among 744 pregnant women attending the prenatal clinic at the University Hospital in Kuala Lumpur, Malaysia. The observed prevalence of gonorrhea (0.54%) in pregnant women is similar to that in Great Britain (0.2-0.7%), but lower than the prevalences reported for North America (2.5-7.5%) and Thailand (11.9%). The results indicate that routine screening of pregnant women attending prenatal clinics in Malaysia would aid in the control of gonorrhea in that country.
The 1980 malaria notifications in Malaysian soldiers are analysed. The number of new cases notified was 964, giving an annual incidence of11.81/1000 soldiers. Sixty-three percent were falciparum and 36 percent were vivax infections. There were 48 relapses and recrudescences. Twenty-three carriers were detected on mass screening. The yield from mass screening was very low - 5.09/1000 screened. The current practice of chemotherapy, though generally acceptable, was unsuitable for a number of patients. Recommended regimens are not being adhered to. There were two cases ofcerebral malaria, one of whom died.