Food irradiation: a public health challenge for the 21st century.

Although the United States food supply is generally considered one of the safest in the world, foodborne illnesses remain a concern. Each year, millions of Americans become ill and as many as 5000 die from foodborne infections. The United States Department of Agriculture estimates that medical treatment and productivity losses associated with foodborne illnesses cost as much as $37 billion annually. Irradiation, which involves exposing food briefly to radiant energy, can reduce or eliminate microorganisms that contaminate food or cause spoilage. So far, only limited quantities of irradiated foods--spices, herbs, dry vegetable seasonings, and some fresh fruits, vegetables, and poultry--have been available in the United States. Major purchasers are health care and food service establishments. The World Health Organization reviewed 500 studies and concluded that food irradiation poses no toxicological, microbiological, or nutritional problems. In more than 40 years, there have been no accidents in North America involving transport of the types of radioactive isotopes used for irradiation.

Polish and American collaboration on zoonotic parasitic studies, 1960 to 1997.

The Marshall Plan of 1947 kindled interest in research in Europe. The U.S. Public Health Service encouraged the use of blocked national currencies to research disease problems. The parasitic diseases were epidemic/epizootic problems in Poland. The initial project was trichinellosis. The 10-year study emphasized the natural history, epidemiology, diagnosis, and therapy of trichinellosis in Poland. The wildlife source of trichinellosis was widespread. Clinical studies discounted the effectiveness of mebendazole but found steroids useful. Taenia saginata is common in Eastern Europe. T. saginata cystericosis in cattle is not easily diagnosed. Physical examination by meat inspectors missed 50% of the infected carcasses. Taenia solium is uncommon. Giardiasis is declining in Poland. The epidemiology of giardiasis in Poland is different from that in the United States, where water-borne infections are common. A study of toxoplasmosis revealed a low prevalence in women but a high prevalence in cats. No cases were identified in 4,311 newborns.

Food irradiation: a public health opportunity.

Public health scientists have had an interest in food irradiation for a hundred years and more. The first investigations occurred within a few years of the discovery of x-ray and short wavelength by the German physicist Roentgen, in 1895. German and French scientists carried on studies on pasteurization of food by radiation until 1914 and the war years. The problem was an unacceptable taste following irradiation. In 1921, the x-ray was reported by the scientists of the United States Department of Agriculture (USDA) to be effective in killing Trichinella cysts in pork and that it could kill disease-causing organisms and halt food spoilage.

Knowledge-based patient screening for rare and emerging infectious/parasitic diseases: a case study of brucellosis and murine typhus.

Many infectious and parasitic diseases, especially those newly emerging or reemerging, present a difficult diagnostic challenge because of their obscurity and low incidence. Important clues that could lead to an initial diagnosis are often overlooked, misinterpreted, not linked to a disease, or disregarded. We constructed a computer-based decision support system containing 223 infectious and parasitic diseases and used it to conduct a historical intervention study based on field investigation records of 200 cases of human brucellosis and 96 cases of murine typhus that occurred in Texas from 1980 through 1989. Knowledge-based screening showed that the average number of days from the initial patient visit to the time of correct diagnosis was significantly reduced (brucellosis-from 17.9 to 4.5 days, p = 0.0001, murine typhus-from 11.5 to 8.6 days, p = 0.001). This study demonstrates the potential value of knowledge-based patient screening for rare infectious and parasitic diseases.

History of veterinary public health in the United States of America.

Animal medicine, human medicine and public health have been associated ever since sheep, goats, cattle, horses, dogs, cats and other animals were first domesticated to serve the needs of society. The more recent history of veterinary public health (VPH) in Europe has seen developments through the seventeenth and eighteenth centuries, and the beginning of modern conceptions of VPH. The recognition of animal disease problems as they have affected public health in the Americas carries the reader forward into the nineteenth and twentieth centuries. Advances made in public health and veterinary medicine in the latter years are reviewed, together with the way in which they have benefited both humans and animals. For the period since 1945, the article reviews the organization of VPH in national governments and international agencies, i.e. the World Health Organization (WHO) and Pan American Health Organization (PAHO). These international health agencies have promoted VPH in national governments. Some of the leaders are recognized for their contributions.

Biochemical properties of group G streptococci isolated from cats and man.

The biochemical characteristics of group G streptococci isolated from cats were markedly similar to the characteristics of group G streptococci from man. Both cat and human isolates of group G streptococci were also very similar in biochemical characteristics to group A streptococci so that to identify the source of group G streptococci by biochemical reactions is not a reliable procedure. The group G streptococci found in many cats could be pathogenic to man, since their physiological and biological characteristics are very similar to those of group A streptococci.

Multiplication in human blood and deoxyribonuclease production by group G streptococci isolated from animals and humans.

An M protein or an M protein-like substance was found to be present in a large proportion of group G streptococci isolated from animals and humans. Forty-seven percent of the isolates from cat throats and 38% of the isolates from the vagina of cats were able to multiply in human blood. Only 14% of the human isolates of group G isolated from various anatomical sites and sources were able to multiply in fresh human blood. Deoxyribonuclease was produced by 81% of cat vagina isolates, by 80% of cat throat isolates and by only 27% of the group G isolates from humans. Thirty-five percent of the cat isolates but only 5% of the human isolates were able to both grow in blood and produce DNase.

The occurrence of nicotinamide adenine dinucleotide glycohydrolase and the serum opacity reaction in groups B, C, F and G streptococci.

The frequency of the serum opacity reaction (SOR) and nicotinamide adenine dinucleotide glycohydrolase (NADase) production in non-A groups of beta-haemolytic streptococci isolated from humans and animals was surveyed. The SOR was positive with five of eighteen group B isolates (28%), four of fifteen group C (27%), two of five group F (40%), and thirty-seven of sixty-eight group G (54%) isolates. NADase activity, in addition to SOR, was found in three of eighteen group B isolates (17%), three of fifteen group C (20%), forty of sixty-eight group G (59%), and none of the group F isolates. The SOR was produced by forty-eight (45%) and NADase was produced by fifty-one (48%) of the one hundred and six isolates of non-group A beta-haemolytic streptococci. Twenty-five percent of the isolates were both NADase and SOR positive.