Breast cancer and cigarette smoking

It has been suggested that cigarette smoking may reduce the incidence of breast cancer, perhaps by as much as 20 per cent. To evaluate the relation between breast-cancer risk and smoking, we studied 2160 women with breast cancer and 717 controls who had been admitted to the hospital for cancer of the ovary, cancer of the colon or rectum, malignant melanoma, or lymphoreticular cancers. As compared with women who had never smoked, the estimated relative risk of breast cancer was 1.1 for current smokers of any amount (95 per cent confidence interval, 0.9 to 1.3), and 1.0 (0.8 to 1.3) for heavy smokers (15 or more cigarettes per day). Allowance for all identified potential confounding factors did not materially alter the results. There was no indication that age at commencement of smoking was related to the risk, nor was there evidence of an effect of smoking within the categories of age at first pregnancy or age at menopause. The data provide evidence against the hypothesis that smoking may reduce the incidence of breast cancer by 20 per cent.

Creutzfeldt-Jakob Disease. Possible transmission to humans by consumption of wild animal brains

Although the natural mode of spread of the agent responsible for Creutzfeldt-Jakob disease is unknown, several reports suggest oral transmission through consumption of contaminated food or brain. This report summarizes four cases of Creutzfeldt-Jakob disease in which a history of eating the brains of wild goat or squirrel was obtained. These cases support the hypothesis of possible acquisition of Creutzfeldt-Jakob disease by ingestion of the agent from a presumptive reservoir in the central nervous system of wild animals.

The effect of westernization on urine estrogens, frequency of ovulation, and breast cancer risk. A study of ethnic Chinese women in the Orient and the USA

In a 10-year incidence survey of breast cancer in the City of Boston, 14 cases in American Chinese women were observed, while approximately 13 were expected on the basis of age-specific incidence in the white population. In Hawaii, on the other hand, while breast cancer incidence rates for ethnic Chinese are approximately three times as high as those of indigenous Chinese populations, data indicate that they are still 35% lower than those of whites in Hawaii or on the US mainland. We have compared estrogen concentrations in the urine of Chinese women in the Orient, Honolulu, and Boston. Levels of estrone (E1) and estradiol (E2) increased greatly from the low to the high risk group. The increase was evident among both the younger (15-19 years) and the older (20-24 years) women, in both follicular and luteal phase specimens. The crude unweighted average increase from Oriental to continental US Chinese was about 38% and 34% for E1 and E2, respectively. On the other hand, levels of E3 decreased from the low-risk to the high-risk group, but the decrease was modest (16%) and not always regular. There were no systematic or significant differences in the frequency of ovulation in the three groups of women. These results are compatible with the hypothesis that high levels of estrone and estradiol are important to breast carcinogenesis. Whether E3 has some additional "protective" effect or is irrelevant is unclear. The data do not support the hypothesis that total urine estrogens (E1 + E2 + E3) are predictive of population groups at high risk for breast cancer and they appear inconsistent with the hypothesis that frequency of ovulation (or anovulation) is an important aspect of breast carcinogenesis.

High-risk young mothers: infant mortality and morbidity in four areas in the United States, 1973-1978

An examination of the changes in infant mortality and morbidity in four regions in the United States has revealed high levels of health problems among the infants of two groups of mothers: those less than or equal to 17 years and 18-19 year-old multiparas, many of whom began their childbearing under age 18. Despite decreases over the period of observation, neonatal mortality rates remain over one and a half times as high for infants of these mothers as for other mothers, largely due to the relatively high proportion of low birthweight (LBW) infants born to these mothers. Post-neonatal mortality rates also remain high, and may be increasing; this change cannot be explained solely by differences in proportion of LBW infants between these and older mothers. Both the high post-neonatal mortality rates and the type of morbidity experienced by surviving infants is consistent with the socioeconomic disadvantage of young mothers. The data further indicate the limited resources available to these mothers to cope with their children's health needs, and their potential vulnerability to decreases in public programs supporting child health care.

HLA and disease

This review describes the greater portion of a large number of new studies on HLA and disease association which has appeared in the literature since 1979. The majority of these are concerned with the association of certain diseases with class II major histocompatibility complex antigens. The possible biologic significance of these associations in terms of their probable etiology appears to be the prevailing theme. Current thinking regarding certain heritable diseases is described. It seems that although much has been done to resolve the genetics of insulin-dependent diabetes mellitus, other diseases such a multiple sclerosis still remain a mystery. Doubtlessly, much will be gained from DNA cloning and sequencing studies proposed for the future. A great deal of new information has been obtained relative to HLA itself. New loci have been postulated in the HLA-D/DR region through the use of powerful immunochemical procedures made possibly by the advent of modern technological advances. The impact of these developments on our understanding of the function of the MHC in man and its possible relationship to disease are discussed.

Rapid death of infant rhesus monkeys injected with Clostridium difficile toxins A and B: physiologic and pathologic basis

Clostridium botulinum can colonize and produce botulinal toxin in the human infant intestine, which the toxin then permeates to cause generalized flaccid paralysis, and occasionally, sudden death. This study was undertaken to test the hypothesis that toxins produced by other intestinal clostridia, e.g., C. difficile, might also cause systemic illness and sometimes death in infants (J Pediatr 100:568, 1982). Because this hypothesis could not be evaluated clinically until the systemic manifestations of C. difficile toxins in primates were known, infant rhesus monkeys were given 6 to 11 micrograms/kg of the recently purified C. difficile toxins A or B, either intravenously or intraperitoneally. The animals showed no abnormalities for several hours, but then developed lethargy, hypotonia, hypothermia, and, shortly before death, sudden elevation of serum concentrations of potassium, magnesium, and phosphorus and of enzymes that derived mainly from skeletal muscle, heart and brain. Five of six animals died quietly 3.5 to 8.0 hours after onset of symptoms. Death appeared to result from cessation of breathing, after which the sinus tachycardia then deteriorated to a flat ECG. Necropsy findings were insufficient to explain the cause of death. It appears that in infant monkeys microgram amounts of C. difficile toxins A and B can produce a rapid quiet death, the cause of which is undetectable at necropsy, a situation pathologically reminiscent of crib death in human infants, although the possible clinical identity of these two conditions has yet to be established.

Endocrine characteristics of adolescent menstrual cycles: impact of early menarche

An initial group of 200 girls, 7-17 years old, was investigated longitudinally 4 times at 1.5-, 1.5- and 5-year intervals. The present study gives information of the impact of early menarche, a risk factor for breast cancer, on some physical and endocrine characteristics in these subjects. The frequency of ovulation depended significantly on both the time since menarche and the age at menarche. Early menarche was associated with early onset of ovulatory cycles. Even in early puberty, before menarche, the subjects who displayed early menarche during follow-up had higher serum FSH and estradiol concentrations than the girls whose menarche took place after the age of 13.0 years. Adrenal androgen secretion (dehydroepiandrosterone) was not influenced by age at menarche but it increased, as expected, on the basis of chronological age. The group with early menarche was characterized by high circulating estradiol concentrations also after menarche, even in the oldest subjects so far studied, 17-25 years of chronological age. At these ages, the differences in the frequencies of ovulatory cycles were disappearing between the groups formed on the basis of age at menarche. The present findings in pre- and postmenarcheal subjects suggest that the increased risk of breast cancer associated with early menarche is created over several years of exposure to high-level estrogen stimulus.

Hypothesis of leprosy, tuberculosis and urbanization in Africa

Leprosy today is a problem of global magnitude affecting possibly up to 15 million people. Its rise and fall in medieval Europe is an historically fascinating enigma. Partial cross-immunization by epidemic tuberculosis, reinforced by the growth of cities, has been proposed as a mechanism in leprosy's European disappearance, but evidence is lacking. In the case of Africa in recent decades, analysis of leprosy and tuberculosis rates, and of levels of urbanization, albeit with imperfect data, suggests a possible environmental health for leprosy, the existence of some cross-interference between tuberculosis and the milder, paucibacillary form of leprosy, and a negative correlation between leprosy and urbanization. It is argued that the rise of the city in Africa, acting through a combination of influences, including tuberculosis, is leading to a decline of leprosy.

Occurrence of hepatitis A, B, and non-A/non-B in the United States. CDC sentinel county hepatitis study I

To determine the relative occurrence of hepatitis A, B, and non-A/non-B in the United States, serum samples and epidemiologic data were collected from patients with hepatitis in five selected counties. Overall, 41, 33, and 26 percent of the patients had hepatitis A, hepatitis B, and hepatitis non-A/non-B, respectively. The incidence, especially of hepatitis A, varied considerably. All three types of hepatitis occurred more frequently in those 15 to 44 years of age. Hepatitis A predominated in those less than 15 years of age and non-A/non-B predominated in those older than 44 years. There was a male predominance (65 to 62 percent) for hepatitis A and hepatitis B, but non-A/non-B occurred equally in both sexes. There was no seasonal pattern for any type. Risk factors for hepatitis A were previous contact with a patient with hepatitis (26 percent), homosexual (male) preference (15 percent), and day-care center contact (11 percent). For hepatitis B, risk factors included drug use (26 percent), previous contact with an infected person (22 percent), homosexual preference (12 percent), and a health-care occupation (12 percent). For hepatitis non-A/non-B, risk factors included drug use (16 percent), transfusion (12 percent), and previous contact with an infected person (12 percent). Previous hospitalization appeared to be a risk factor for both hepatitis B and hepatitis non-A/non-B.

The use of IgM tests for analysis of the causes of measles vaccine failures: experience gained in an epidemic in Hungary in 1980 and 1981

Following a period of 6 years of low measles incidence, an epidemic occurred in Hungary with more than 11,000 reported cases between September 1980 and August 1981. About 60% of the cases had a documented history of previous measles vaccination. Serum samples obtained from 7815 patients were examined for measles antibody by haemagglutination inhibition (HI). In addition to conventional antibody titration, most of the sera or their IgM fraction obtained by a simple ion exchange chromatography were tested for the presence of measles-specific IgM antibodies by 2-mercaptoethanol (2-ME) treatment, and in 300 patients also by the fluorescent antibody (FA) technique. Laboratory results confirmed the diagnosis of measles in 5356 patients and supported it in 685 cases. Primary antibody response was found in 96.1% of unvaccinated and in 77.4% of previously vaccinated patients. The percentage of secondary antibody responses increased with increasing time from vaccination only in patients vaccinated before their first birthday, whereas in those who were immunized when over 12 months old, the distribution of primary and secondary antibody responses was independent from the time that had elapsed since vaccination. Therefore, secondary vaccine failure due to waning immunity account for only 6.2% of previously vaccinated patients, whereas in 93.8% of patients, including the majority of those with secondary antibody response, a primary failure of vaccination due to unsuccessful immunization was incriminated.

Infectious mononucleosis in Greenland: a disease of the non-indigenous population

Greenland Eskimos have one of the highest incidences of nasopharyngeal carcinoma (NPC) in the world. Asian and African areas endemic for NPC show early infection with Epstein-Barr virus (EBV), and few cases of infectious mononucleosis (IM). Among 40 000 Eskimos and 10 000 Caucasians in Greenland there were 82 reported cases of IM from 1963 to 1980. Incidence rates from 1975 to 1980, age adjusted to the "world" population distribution, were 12.0 and 5.2/100 000/yr for males and females, respectively. Comparable Danish data revealed incidence rates of 97.4 and 105.1. From 1970 to 1981 Greenland hospital records verified 16 cases, of which only 2 were in Eskimos. The IM incidence in Eskimos is extremely low, and Danes living in Greenland have a comparatively much higher incidence.

A prospective study of urinary androgen levels and ovarian cancer

The three major urinary androgen metabolites, dehydroepiandrosterone (DHEA), androsterone (ANDRO), and aetiocholanolone (AETIO) were measured in 1,484 volunteer women between 29 and 60 years of age on the island of Guernsey from 1962-1967. Twelve of these women subsequently developed ovarian cancer after a median interval of 130 months and a minimum interval of 19 months. All three androgen levels in these women were lower than those in controls matched for age and menopausal status. The results were most striking for DHEA, where half of the cases were below the 27th percentile of their matched controls (p = 0.007, two-sided). The results for ANDRO were of marginal significance (p = 0.06), and those for AETIO were not significant (p = 0.33).

Risk factors relevant to cystic breast disease: a case-control study

A total of 188 women aged 40-54 with cystic breast disease and 2213 asymptomatic controls were questioned in Edinburgh between 1974 and 1978 concerning marital, reproductive, and menstrual status, history of oral contraception use, history of previous breast complaints, and a family history of breast cancer. Women with a history of breast biopsy were at an increased risk of the disease and those past the menopause were at a decreased risk. These results agree with previous findings that the disease is most prevalent among premenopausal women and suggest that benign cystic disease of the breast does not share a common aetiology with breast cancer in the age range 40-54.

Infant botulism in the United States: an epidemiologic study of cases occurring outside of California

Data were obtained for the 96 hospitalized cases of infant botulism reported to the Centers for Disease Control between 1976-1980 from all states other than California. Forty-one cases were associated with Clostridium botulinum type A, 53 with type B, one with type F, and one with a strain of C. botulinum capable of producing both type B and F toxin. Cases occurred in 25 states; the disease was more common in the western part of the United States, with the highest attack rates reported for Utah and New Mexico. Birth-weights of hospitalized infants with infant botulism tended to be high compared with birth-weights in the United States population. Mothers of infants with infant botulism tended to be older and better educated than mothers in the general population. Seventy per cent of infants had been predominantly breast-fed; breast-feeding in type B cases was associated with a significantly older age at onset of illness.

Intestinal colonization of infant hamsters with Clostridium difficile

Infant hamsters of different ages were examined for their susceptibility to enteric Clostridium difficile colonization. Intragastric administration of C. difficile to infant hamsters resulted in multiplication of the organism in the intestinal tracts of animals 4 to 12 days old; hamsters younger or older were resistant to C. difficile intestinal colonization. Toxicity to the colonized animals could not be demonstrated despite cytotoxin titers in some infant hamsters comparable to titers found in the intestinal tracts of adult hamsters with C. difficile-associated intestinal disease. When introduced into 4-day-old hamsters, C. difficile colonized the intestinal tract and remained at high levels until the animals were 13 days old, at which time the presence of intestinal C. difficile could no longer be demonstrated. The number of C. difficile required to colonize the intestinal tracts of 50% of 7-day-old hamsters was 18 viable cells. On the other hand, 10(8) viable cells of C. difficile failed to colonize the intestinal tracts of healthy, non-antibiotic-treated adult hamsters.

Antigens in whooping cough vaccine and antibody levels induced by vaccination of children

The content of 3 antigens--filamentous haemagglutinin, lymphocytosis-promoting factor, and serotype-specific agglutinogens (fimbriae)--was determined in the current UK whole-cell whooping cough vaccine. Antibodies to these antigens and to outer membrane proteins and lipopolysaccharide of Bordetella pertussis were measured in the serum of unvaccinated children and children who had received 1, 2, or 3 doses of the vaccine. Children who had received one dose of vaccine had varied low antibody titres. Children who had received two or three doses had significantly higher antibody titres to all the antigens tested, as did some unvaccinated children with no history of whooping cough. This study shows that filamentous haemagglutinin, lymphocytosis promoting factor, and outer membrane proteins are immunogenic constituents of the whole-cell vaccine. Their inclusion in a subcellular vaccine would not involve novel antigens.

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. Duplicate hybridization assays in two laboratories were in close agreement. Serological testing showed that 91% of the confirmed BL cases had elevated EBV/VCA titres (greater than or equal to 160) and 64% were EA(D)-positive (greater than or equal to 10). Most of the cases with high EBV/genome content had high VCA titres, but there was a poor correlation between the two parameters among all cases. This study confirms that in high BL incidence areas the association between EBV and this lymphoma is almost constant, whereas it is exceptional in low-incidence areas. This further supports the aetiological implication of EBV in the endemicity of this tumor in equatorial Africa.

Scrapie in France: some possible predisposing factors in the naturally-acquired disease of sheep

A nationwide survey of the occurrence of scrapie in France during the 12-year period 1968-1979 has shown the disease to be more widespread than previously thought. The data suggest that certain sheep raising practices, such as transhumance (nomadic grazing), pen and pasture alternations, and use of animals for milk production, may play a possible role in disease prevalence.

The prevalence and incidence of juvenile rheumatoid arthritis in an urban Black population

We determined the prevalence and incidence of juvenile rheumatoid arthritis (JRA) in an urban Black population in Baltimore, identifying three cases through review of computerized outpatient encounters and a fourth case by reviewing discharge records at area hospitals. The prevalence of JRA among Blacks, as of December 31, 1980, was estimated as 0.26 per 1,000 (95 per cent confidence interval: 0.07, 0.66), the average annual incidence 6.6 per 100,000 per year (0.8, 23.8) for the years 1979 and 1980. These data suggest that Black race is not associated with significantly increased risk of development of JRA.

Relationship of fluorescent lights to malignant melanoma: another view

In an attempt to determine whether exposure to fluorescent lights may cause an increased risk for developing melanoma, 114 patients with melanoma were compared to 228 age-matched controls. Fluorescent-light exposure, along with 10 other risk factors, was analyzed for its possible relationship to malignant melanoma. No association was found between fluorescent-light exposure and increased risk for acquiring malignant melanoma.

The risks associated with teenage abortion

the risks of morbidity and mortality affect a teenager's choice between termination of a pregnancy through induced abortion and continuation of the pregnancy. To identify these risks, we analyzed information from two separate sets of data collected by the Centers for Disease Control: that of the Joint Program for the Study of Abortion, a multicenter prospective study of nearly 165,000 legally induced abortions; and that of a national surveillance of abortion-related mortality. The rates of major complications associated with abortions in teenagers were 1 to 3 per 1000 suction-curettage procedures and approximately 13 per 1000 saline-administration procedures. The death-to-case rate for teenage women was 1.3 per 100,000 procedures. When the data on procedures were adjusted according to gestational age, teenagers generally had lower rates of morbidity and mortality from induced abortion than older women.

Relationship between infant death and maternal age. Comparison of sudden infant death incidence with other causes of infant mortality

The high incidence of sudden infant death syndrome in infants born to teenage mothers prompted us to search for epidemiologic clues that might relate to SIDS causation. The death rate for SIDS was compared with that of other major causes of infant mortality in two maternal age groups (younger than 20 years and 30 to 34 years). In the neonatal period, a significantly greater overall mortality occurred in infants born to the younger mothers. This difference was primarily related to an excess of low-birth-weight infants dying from diseases of early infancy. "Weight-specific" mortality, however, was similar for the two groups. In the postneonatal period, when most SIDS occurs, the incidence was 5.2 per 1000 among infants of teenage mothers, compared with 1.0 in infants of the older mothers. A similar maternal-age-related incidence was observed for death from infections, accidents, and "other causes." By contrast, death from congenital anomalies was unrelated to maternal age in both periods. We conclude that many postneonatal deaths are influenced by environmental factors, including the age and maturity of the mother.

Inactivation of hepatitis B virus by intermediate-to-high-level disinfectant chemicals

In five separate tests, hepatitis B virus in dried human plasma was exposed for 10 min at 20 degrees C to disinfectant chemicals having activity levels ranging from intermediate (e.g., 70% isopropyl alcohol) to high (e.g., 2% aqueous glutaraldehyde at pH 8.6). Five chimpanzees (one animal per disinfectant chemical) received treated material intravenously, and none showed signs of infection after post-inoculation periods of 9 months. Two animals were rechallenged with inoculum treated in the same manner, except that saline was used instead of a disinfectant chemical; both were infected within 4 weeks. Our results showed that hepatitis B virus was not as resistant to disinfectant chemicals as once thought and suggested that chemicals with similar activity levels (intermediate to high) might possibly be used on hepatitis B virus contamination with a margin of safety.

Sentinel Health Events (occupational): a basis for physician recognition and public health surveillance

A Sentinel Health Event (SHE) is a preventable disease, disability, or untimely death whose occurrence serves as a warning signal that the quality of preventive and/or therapeutic medical care may need to be improved. A SHE (Occupational) is a disease, disability, or untimely death which is occupationally related and whose occurrence may: 1) provide the impetus for epidemiologic or industrial hygiene studies; or 2) serve as a warning signal that materials substitution, engineering control, personal protection, or medical care may be required. The present SHE(O) list encompasses 50 disease conditions that are linked to the workplace. Only those conditions are included for which objective documentation of an associated agent, industry, and occupation exists in the scientific literature. The list will serve as a framework for developing a national system for occupational health surveillance that may be applied at the state and local level, and as a guide for practicing physicians caring for patients with occupational illnesses. We expect to update the list periodically to accommodate new occupational disease events which meet the criteria for inclusion.

Significance of hypertension in children

This article does not consider the secondary causes of high blood pressure in children. Essential hypertension is a major factor in the morbidity and mortality from cardiovascular disease among adult populations throughout the world. The possibility that a raised blood pressure may have its origins in childhood or even in infancy is being extensively explored. Accurate measurement of blood pressure--especially systolic--is now feasible, by the Doppler technique, in very young children. The concept of "tracking" of blood pressure has been investigated. In addition, factors such as familial aggregation, genetic aspects, and the role of obesity in the etiology of hypertension have been considered. The reason for differences in the severity of manifestation of hypertension in black and white populations has not been satisfactorily elucidated, despite a number of childhood population studies. With an increased number of blood pressure measurements more children are being discovered with labile or even essential hypertension. The exact level above which to consider therapy is somewhat controversial. Nevertheless, even with mild persistent elevations, nonpharmacologic measures such as control of obesity, reduction in salt intake, regular exercise, potassium supplementation, and relaxation therapy, seem warranted. These measures should also be seriously considered in the prevention of hypertension in young urban populations.

Grade I Reye's syndrome. A frequent cause of vomiting and liver dysfunction after varicella and upper-respiratory-tract infection

In a one-year prospective study we assessed the incidence of Reye's syndrome in children presenting with the acute onset of vomiting after a prodromal upper-respiratory-tract infection or varicella, and with serum alanine or aspartate aminotransferase levels at least three times higher than normal, and a paucity of neurologic findings. Of 25 patients meeting the above criteria, 19 had liver biopsies yielding adequate tissue for diagnostic purposes. Biopsy specimens from 14 of these 19 patients (74 per cent) were diagnostic of Reye's syndrome, according to rigorous light-microscopical, histochemical, and ultrastructural criteria. None of the biopsy specimens contained evidence of other acute pathologic processes, including hepatitis. A wide spectrum of mitochondrial alterations existed at the ultrastructural level, ranging from mild to severe lesions that were indistinguishable from those seen in comatose patients with Reye's syndrome. Our findings suggest that the clinical complex of vomiting, hepatic dysfunction, and minimal neurologic impairment after varicella or an upper-respiratory-tract infection usually represents Reye's syndrome. This syndrome occurs more frequently than previously recognized.

Pancreatic islet and other autoantibodies in juvenile and adult onset diabetics in Australia

The prevalence of serum antibodies to the cytoplasm of the pancreatic islet cell (PICA), and of thyroid microsomal (TMA), gastric parietal cell (GPCA) and anti-nuclear (ANA) antibodies was studied in 135 newly diagnosed diabetics presenting to a hospital for adults and 83 children with recent onset diabetes presenting to a children's hospital. The study also included another 144 diabetic children whose disease had been present longer, and 200 control children. There was a high prevalence (87%) of PICA in the children whose diabetes had just been diagnosed in comparison with control children (1%):(P less than .0001). Diabetic children also had a high prevalence (21%) of one or more of the other autoantibodies in comparison with the control children (9%):(P less than .001). Only 26% of the 58 insulin dependent adults had PICA but 33% had other autoantibodies. Two (3%) of the 77 adult diabetics who did not require insulin had PICA; 8% had other autoantibodies.

Correlation between population density and the frequency of Creutzfeldt-Jakob disease in France

Epidemiologic studies of Creutzfeldt-Jakob disease (CJD) in countries throughout the world have consistently shown higher urban than national disease frequencies, but this finding has usually been ascribed to case-finding artefact. A detailed analysis has now been completed of annual mortality rates of CJD in France, based on a systematic study of 255 consecutive cases dying during the period 1968-1980, of whom 85 resided in the paris metropolitan area. In the country as a whole, the frequency of CJD increased from rural, through urban, to the Paris region; and in the Paris region, the frequency increased from the lowest to the highest density areas. The magnitude of this positive correlation between population density and the frequency of CJD is not explained by differences in age distribution of the various population groups, and suggests a role for random inter-human spread, either direct or indirect, in natural disease transmission.

A survey of cancer morbidity and mortality in vaccinees seven to 12 years after the administration of live vaccine propagated in human diploid cells

Using record linkage, cancer morbidity and mortality were examined in 2973 recipients of RA 27/3 strain rubella vaccine propagated in WI 38 cells. During the follow-up reported (mean duration 9.8 years; range seven to 12 years) the rate of cancer notifications and of deaths from cancer were similar to those observed in the equivalent age range of the general population.

A comparison of Epstein-Barr virus-specific T-cell immunity in malaria-endemic and -nonendemic regions of Papua New Guinea

Epstein-Barr virus genome-positive Burkitt's lymphoma is endemic in Africa and Papua New Guinea and in both countries the tumour is restricted to regions with holoendemic malaria. The present work has compared groups of healthy indigenous individuals living in malarious and non-malarious regions of Papua New Guinea for Epstein-Barr virus-specific T-cell-mediated immunity using the in vitro regression assay. Residents of the malarious region (55 tested), when compared with either residents of the non-malarious area (35 tested) or Caucasian controls (27 tested) showed a significant (p less than 0.0001) impairment of virus-specific T-cell immunity but no obvious disturbance (p greater than 0.05) of anti-viral antibody titres. These results may be important in explaining the postulated role of malarial infection as a co-factor in the pathogenesis of Burkitt's lymphoma.

Trends in malignant melanoma of skin in New Zealand

Incidence and mortality rates for malignant melanoma of skin in the New Zealand non-Maori population over the past 30 years were analysed in relation to sex, age, birth cohort and time. In both sexes, the age-standardized incidence rates increased approximately exponentially with time, with an annual increment of 7.5%. The age-standardized mortality rates increased approximately linearly with time, resulting in a two- to three-fold increase over 30 years, as compared with an eight- to nine-fold increase in the incidence rates. Descriptive birth cohort analysis shows different patterns of increase for incidence and mortality rates. The main difference is that, whereas incidence rates have continued to increase in recent birth cohorts, mortality rates have stabilized. The explanation for this difference is uncertain.

Bladder cancer in Spain. Mortality trends (1955-1975)

Studies made of mortality tendencies due to bladder cancer made in various industrialized countries show evidence of an increase with time in death rates. This situation is also seen in Spain with some characteristics which we analyze. An actual increase of 60% in risk of death due to bladder cancer in males was found between 1955 and 1975. A definite tendency in women was not observed. The characteristics of the tendency curves indicate the grave importance that this tumor could eventually have in Spain and the need to adopt a policy of adequate intervention.