Food-borne parasitic infections — A review

A review of food-borne parasitic infections is presented. Parasitic infections in conventional slaughtered animals and seafood (fish and shellfish) constituting a public health hazard are discussed. To the former category belong cysticercosis, echinococcosis and trichinellosis, and to the latter category belong various trematole, cestode and nematode infections. Examples of trematode infections are heterophyidiasis, transmitted to man by marine fish and Paragonimus spp. parasites, transmitted by crustaceans. Cestode infections include diphyllobothriasis transmitted by freshwater fish and fish from brackish waters. Special attention is drawn to the condition known as sparganosis. Of the nematode infections the eosinophilic granulomatous enteritis is mentioned. It is due to infections with members of the genera Anisakis, Phocanema and Contracaecum and is transmitted to man by either marine fish of crustaceans. Two other nematode infections Angiostrongylus cantonensis and Capillaria philippinensis can also be transmitted to man by marine fish.Apart from a possible direct effect of these parasites, chemical alterations in seafood resulting from the presence of parasites may also be deleterious to the consumer.Special attention is drawn to a newly developed serological detection method, the enzyme-linked immunosorbent assay, enabling not only detection of infection at the slaughter-house, but also in large herds at the farm.Strategies to control parasitic infections both in conventional slaughtered animals and in seafood are discussed.     

Food-borne parasitic infections - old stories and new facts

Summary A review is presented of food-borne parasitic infections. Parasitic infections with public health hazards both from conventional slaughter animals and from seafood (fish and shellfis) are discussed. The former category includes cysticercosis, echinococcosis, and trichinosis, the latter category covers various trematode, cestode, nematode, and possibly also protozoan infections. Examples of trematode infections are heterophyidiasis, transmitted to man by marine fish, and Paragonimus spp parasites, transmitted by crustaceans. Cestode infections include diphyllobothriasis transmitted by both fresh waterfish and fish from brackish waters. Special attention is drawn to the condition known as sparganosis. Of the nematode infections, the eosinophilic granulomatous enteritis due to the genera A nisakis, Phocanema, and Contracaecum, transmitted to man by either marine fish or crustaceans, is mentioned. Two other nematode infections. Angiostrongylus cantonensis and Capillaria philippinensis, can also be transmitted to man by marine fish. Free living amoebae (a.o. Naegleria) may be transmitted to man via shellfish as vehicles. Apart from a possible direct effect of these parasites, chemical alterations in seafood resulting from the presence of parasites may also be deleterious to the consumer. Special attention is drawn to a newly developed serological detection method, the enzyme-linked immunosorbent assay, which makes detection of infection possible not only at the slaughterhouse but also at the farm or in large herds. Strategies to control parasitic infections both in conventional slaughter animals and in seafood are discussed.     

Baylisascariosis (Baylisascaris procyonis)--a rare parasitic zoonosis in Europe

Raccoons (Procyon lotor) were imported from North America into Germany many decades ago, and nowadays they are part of the home wildlife fauna. Unfortunately, the raccoon roundworm, Baylisascaris procyonis, was also imported. This nematode species is well known as an important agent of larva migrans in more than 100 animal species including man in North America, causing a fatal neurological or severe ocular disease. There are also several respective reports from Germany. A review about the biology of B. procyonis as well as the occurrence, epidemiology, pathology, clinical symptoms, zoonotic aspects of the baylisascariosis and possible preventive measurements is given.     

Anthrax undervalued zoonosis

Anthrax is a non-contagious disease, known since ancient times. However, it became a matter of global public interest after the bioterrorist attacks in the U.S.A. during the autumn of 2001. The concern of politicians and civil authorities everywhere towards this emergency necessitated a significant research effort and the prevention of new bioterrorist acts. Anthrax is primarily a disease that affects livestock and wildlife; its distribution is worldwide; and it can represent a danger to humans but especially more so when it occurs in areas considered to be free and in atypical seasons and climatic conditions. The atypicality of the phenomenon may lead health workers to misdiagnose and, consequently, an inappropriately manage of affected carcasses with a consequent and inevitable increase in the risk of human infection. This article emphasises the importance of paying increasing attention to this zoonosis. The biggest risk is its underestimation.     

An emerging zoonosis in Scandinavia -- nephropathia epidemica.

The paper reviews as zoonosis the disease called Nephropathia epidemica in north European countries. The etiology is as yet unsolved but a viral one is highly suspected with small rodents (voles and mice) as the source of infection. Based on the epidemiological peculiarities of the disease, the ecology of the agent and hypothetical ways of transmission of infection from small rodents to man are discussed.     

Toxoplasmosis - a waterborne zoonosis

Humans become infected with Toxoplasma gondii mainly by ingesting uncooked meat containing viable tissue cysts or by ingesting food or water contaminated with oocysts from the feces of infected cats. Circumstantial evidence suggests that oocyst-induced infections in humans are clinically more severe than tissue cyst-acquired infections. Until recently, water-borne transmission of T. gondii was considered uncommon but a large human outbreak linked to contamination of a municipal water reservoir in Canada by wild felids and the widespread infection by marine mammals in the USA provide reasons to question this view. The present paper reviews information on the biology of oocyst-induced infections of T. gondii in humans and animals and examines possible importance of transmission by water.     

Current problems in zoonosis research

New developments in the field of Zoonosis research are discussed. They include: 1. New emerging viral zoonosis 2. Multicausal zoonoses 3. Genetic aspects of the origin of new zoonoses 4. Transmission of zoonoses to man through foodstuffs of animal origin 5. The environment and zoonoses. Continuous zoonosis research with new molecular biological techniques is a necessity. In the final analysis, there are no true limits in the field of infectiology. Such research requires cooperation between ecologists, zoologists, botanists, molecular biologists, physicians and veterinarians.     

Trichinellosis: a worldwide zoonosis

Trichinella spp. are some of the most widespread parasites infecting people and other mammals all over the world, regardless of climate. This paper attempts to describe the present status of trichinellosis worldwide and to determine if and why trichinellosis is emerging or re-emerging. The global prevalence of the disease is difficult to evaluate but as many as 11 million people may be infected. More than 10000 cases of human trichinellosis were reported by the International Commission on Trichinellosis from 1995 to June 1997 and about 10000 porcine infections were reported by the Office International des Epizooties in 1998. The disease is particularly worrisome in the Balkans, Russia, the Baltic republics, in some parts of China and Argentina. Horsemeat-related outbreaks have been reported in France and Italy and have involved about 3000 patients in the past 25 years. The emergence of trichinellosis in some countries is explained by a better knowledge of the disease (formerly often misdiagnosed as influenza), modifications of consumer habits, re-forestation in Europe and increase of wild game, importation of meats from countries where trichinellosis is endemic and failure of veterinary control due to human error or to social upheavals. This disease linked to meat-consumption which is theoretically easy to prevent by adequate cooking, freezing and veterinary controls, should deserve the attention of all persons involved in public health and it could be eradicated at least from domestic pigs.     

Tularaemia: A challenging zoonosis

In recent years, several emerging zoonotic vector-borne infections with potential impact on human health have been identified in Europe, including tularaemia, caused by Francisella tularensis. This remarkable pathogen, one of the most virulent microorganisms currently known, has been detected in increasingly new settings and in a wide range of wild species, including lagomorphs, rodents, carnivores, fish and invertebrate arthropods. Also, a renewed concern has arisen with regard to F. tularensis: its potential use by bioterrorists. Based on the information published concerning the latest outbreaks, the aim of this paper is to review the main features of the agent, its biology, immunology and epidemiology. Moreover, special focus will be given to zoonotic aspects of the disease, as tularaemia outbreaks in human populations have been frequently associated with disease in animals.     

人畜共患病的防治对策

人畜共患病是指人类与人类饲养的畜禽之间自然传播的疾病和感染疾病。20世纪70年代以来,全球范围新出现传染病和重新出现传染病达到60多种,其中半数以上是人畜共患病。人畜共患病是由病毒、细菌、     

Brucellosis: A re-emerging zoonosis

Brucellosis, especially caused by Brucella melitensis, remains one of the most common zoonotic diseases worldwide with more than 500,000 human cases reported annually. The bacterial pathogen is classified by the CDC as a category (B) pathogen that has potential for development as a bio-weapon. Brucella spp. are considered as the most common laboratory-acquired pathogens. The geographical distribution of brucellosis is constantly changing with new foci emerging or re-emerging. The disease occurs worldwide in both animals and humans, except in those countries where bovine brucellosis has been eradicated. The worldwide economic losses due to brucellosis are extensive not only in animal production but also in human health. Although a number of successful vaccines are being used for immunization of animals, no satisfactory vaccine against human brucellosis is available. When the incidence of brucellosis is controlled in the animal reservoirs, there is a corresponding and significant decline in the incidence in humans.     

Prevalence of antibodies to five selected zoonosis agents in monkeys.

The prevalence of antibodies against 5 zoonosis agents was determined in serum samples of 443 breeding monkeys. Of the monkeys, 296 were bred or kept for a long time at R institute, and the remaining 147 were newly imported from the Philippines and kept at S institute for quarantine. Antibodies to simian virus 40 were highly prevalent at 89.1% among monkeys of R institute, whereas no antibody could be detected in those of S institute. Antibodies to Chlamydia psittaci and Yersinia pseudotuberculosis were detected in 14.4 and 11.6% at R institute, and in 9.0 and 3.5% at S institute, respectively, evidencing a significant difference (P less than 0.05) between those of the two institutes for both agents. Antibodies to Toxoplasma gondii and Leptospira interrogans were found in 3.6 and 2.9% of the overall, respectively, showing no difference in positive rates in relation to breeding place. Even in cases positive to the latter 4 zoonosis agents, the antibody titers were low. The results obtained suggest that all zoonoses tested do not seem to be so serious diseases among monkeys at the present time except simian virus 40 infection, which is highly prevalent among breeding monkeys in Japan.     

一种新的人畜共患病——尼帕病

尼帕病 (Ｎｉｐａｈ ,有人翻译为宜麦病 )是 1 998年在马来西亚首次发现的鲜为人知的一种人畜共患传染病 ,严重危害人和猪 ,发病急 ,致死率高。其特征性症状是严重的呼吸道和神经症状 ,患者颈部和腹部痉挛 ,公猪和母猪则表现为突然死亡[1] 。1　地理分布及危害1 997年 1月 ,马来西亚霹雳州暗邦地区一个在养猪场工作的工人因病入院 ,其临床症状与其他已知的疾病特别是日本脑炎 (即乙型脑炎 )没有明显的区别 ,被诊断为病毒性脑炎。1 998年发生更多的病例 ,仅约 1 5%的患者可诊断为日本乙型脑炎 ,其余 85%原因不明。此后 ,在一些养猪场也陆续发…     

A case of zoonosis associated with Streptococcus equi ssp. zooepidemicus

A sexagenarian couple operating a dairy farm, where there were also many horses, suffered a severe respiratory infection associated with the bacterium Streptococcus equi ssp. zooepidemicus. The investigation revealed that the source of infection was due to contacts with a horse having an infected wound from which we isolated this zoonotic agent.     

食源性沙门氏菌的PCR检测

该试验根据GenBank数据库沙门氏菌的特有基因invA(AE008832)设计扩增长度为285 bp的引物,研究PCR技术在检测冷冻肉中沙门氏菌的检测限度.在生理盐水中食源性沙门氏菌的检测限度为103 cfu/mL;在人为污染肉汤中,普通FCR的检出限为1.98×103 cfu/mL;人为污染后的样品肉汤中沙门氏菌浓度为100,101,102 cfu/mL时,分别培养7.6.6h即可检测到.     

Buffalopox: an emerging and re-emerging zoonosis

Outbreaks of buffalopox or pox-like infections affecting buffaloes, cows and humans have been recorded in many parts of the world. Since the first outbreak in India, a large number of epidemics have occurred. Unlike in the previous years, generalized forms of the disease are now rare; however, there are severe local forms of the disease affecting the udder and teats, leading to mastitis thereby undermining the productivity of milk animals. The causative agent buffalopox virus (BPXV) is a member of the Orthopoxvirus, and is closely related to Vaccinia virus (VACV), the type-species of the genus. Earlier studies with restriction fragment length polymorphism and recent investigations involving sequencing of the genes that are essential in viral pathogenesis have shown that BPXV is phylogenetically very closely related to VACV and may be considered as a clade of the latter. The review discusses the epidemiology, novel diagnostic methods for the disease, and molecular biology of the virus, and infers genetic relationships of BPXV with other members of the genus.