Introduction: Campylobacter has now become one of the most common causes of diarrheal diseases in industrialized and in developing countries worldwide and is now an important public health concern. Campylobacter often results from poor sanitary conditions and hygienic practices associated with raring, processing, packaging and storage of poultry and poultry products that lead to cross contamination. The disease is serious if not treated and may result in inflammation of the joints, persistence and multiplication of living bacteria in the blood, inflammation of the coverings of the brain, inflammation of the heart and other organs leading to organ failure and eventually system failure, paralysis and death. The purpose of the present paper is to review the current literature and to provide up-to-date information by providing answers to pertinent questions on the public health significance of Campylobacter.

What is campylobacteriosis? Campylobacteriosis is a disease condition caused by bacteria belonging to the genus Campylobacter. Most people experience signs of the disease within 2 to 5 days after exposure to Campylobacter. Signs may vary among patients depending on the sensitivity of the individual, state of health and the pathogenicity of the particular strain of bacteria. Some common signs may include vomiting, nausea, diarrhea, cramping, abdominal pain and fever. Persons with compromised immune systems such as those on medications, radiation therapy, chemotherapy, suffers of diseases such as AIDS and other infectious diseases. The young, old and pregnant individuals are also vulnerable to campylobacteriosis. In these susceptible individuals Campylobacter occasionally spreads to the bloodstream and causes a serious life-threatening infection. Despite the appearance of signs of Campylobacter infection in some individuals, other individuals who are infected may be carriers of the disease and do not show any symptoms and signs of the disease.

How common is campylobacter? Campylobacter is regarded as one of the common causes of diarrheal illness in the United States. Sporadic cases of the disease have accounted for isolated outbreaks throughout the United States. It has been reported that 15 cases of campylobacteriosis are diagnoses each year for each 100,000 persons. The disease is often found and reported more in the summer season than in the winter, in males and immunocompromised individuals. The actual number of cases may be under reported and it is suggested that campylobacteriosis may affect over 1 million persons every year or 0.5 % of the U.S. population.

Campylobacter may not cause death if treated promptly. But in rural environments where access to adequate health care facilities may be a problem and where the seriousness of the disease is underestimated or ignored may lead to deaths. It is estimated that approximately 100 persons with Campylobacter infections may die each year.

What are some of the characteristic features of campylobacter? Campylobacter belongs to a group of spiral curved rod shaped gram-negative bacteria that can cause disease in humans and animals. Campylobacter jejuni is one of the main species that causes most human illness. Other species of Campylobacter can also cause human illness and accounts for just 1 % of cases. Campylobacter lives reasonably well at a temperature of 37.7-43.5 ºC. This temperature range is also the body temperature of birds. As a result Campylobacter jejuni seems well adapted and grows best at this temperature on birds. Poultry and other birds can carry around large numbers of Campylobacter jejuni on their bodies without becoming ill and can be major sources of bacteria contamination. Campylobacter jejuni is temperature sensitive and can be destroyed at high temperatures, in the presence of oxygen (21 %) and at low temperatures (-18 ºC).

How is Camylobacter infection diagnosed? Campylobacter jejuni infection can be detected by clinical diagnosis and then by pathological confirmation. Clinical diagnosis involves detecting the appearance of the symptoms and signs associated with Campylobacter jejuni based on clinical history of the patient. Pathological confirmation involves special laboratory culture procedures performed on a sample of stool and/or blood analysis for the confirmation of Campylobacter jejuni.

How can campylobacteriosis be treated? Healthy persons who have become infected with Campylobacter may recover without any specific treatment. Since dehydration is most likely sign during infection it is highly advisable that, patients should drink plenty of fluids as long as the diarrhea lasts. Antibiotics such as erythromycin or a fluoroquinolone can be prescribed by a physician. These antibiotics tend to shorten the duration of disease and assist in better management of symptoms if they are given early in the illness.

Are there long-term consequences of campylobacteriosis? Recovery from Campylobacteriosis is dependent on the state of health of the person and the pathogenicity of the stain of bacteria. In most infections, recovery may occur within 2-10 days for healthy individuals who are infected. Recovery can take longer and in some cases the disease may progress causing severe morbidity and mortality. Some infected patients may have difficulty moving around because of inflammation of the joints, inflammation of the coverings of the brain, paralysis and eventually death.

How do people get infected with campylobacter? People can become infected with Campylobacter by eating raw or undercooked poultry meat or by handling raw poultry. It takes only a drop of juice from raw chicken meat contains approximately less than 500 Campylobacter to infect a person. Cross contamination during food preparation is one the main ways in which Campylobacter can be transferred from one surface to another. For example infected poultry that is cut on a cutting board that has not been washed and sanitized before it is used to prepare raw vegetables or lightly cooked food can transfer Campylobacter to raw vegetables and other foods. Human-to-human transfer of Campylobacter is possible through contact with infected feces that may contaminate ground surface water used for drinking.

How does food or water get contaminated with campylobacter? Campylobacter is present in intestines of poultry and other animals. Infected animals appear in most cases healthy. Infected animals that share a common water source may contaminate other healthy animals. The feces of infected animals contain high levels of Campylobacter and can easily contaminate food and water consumed by man.

What can be done to prevent campylobacter infection?  Active surveillance and prompt reporting of outbreaks of Campylobacter to local health authorities such as the Poultry Surveillance Unit, Ministry of Agriculture, Public Health Inspectorate, Food and Drugs Inspectorate/Food and Drug Administration and Ministry of Health.  Community education aimed at developing proper food handling practices such as cleaning and sanitizing food contact surfaces, cooking foods to the correct internal temperatures, prevention of cross contamination, good hygienic practices and good storage practices.  Pens and farms where animals are reared for human consumption should be cleaned and sanitized on a regular basis.  Animals should be checked on a regular basis for any symptoms and signs of any diseases. Infected animals should be quarantined and treated appropriately. If treatment is ineffective and infected animals are at an advanced stage or pose a significant public health hazard, culling may be appropriate to save uninfected animals and protect human health and well being.  Watering and feeding utensils should be cleaned and sanitized regularly to prevent harborage of Campylobacter.  Farms, pens and slaughter houses should be inspected and provided with a certificate of Health and Safety by the Poultry Surveillance Unit and other health authorities to ensure contaminated or tainted meat does not reach consumers and pose a public health hazard.

What are some guidelines for preventing campylobacteriosis?  Cook all poultry products thoroughly. Make sure that the meat is cooked throughout and the inside is cooked to 77 ºC for breast meat and 82 ºC for thigh meat.  Do not eat undercooked poultry or meat.  Wash hands thoroughly with soap before handling raw foods of animal origin. Wash hands with soap after handling raw foods of animal origin and before touching anything else.  Prevent cross-contamination in the kitchen and other food preparation areas by: Using separate cutting boards for foods of animal origin and other foods. If separate cutting boards are not available, wash and sanitize cutting boards before and after every use. Carefully clean all cutting boards, countertops and utensils with soap and hot water after preparing raw food of animal origin.  Avoid consuming unpasteurised milk, juice and other untreated surface water used for human consumption.  Make sure that persons with diarrhea, especially children, pregnant, aged and immunocompromised persons wash their hands carefully and frequently with soap to reduce the risk of bacterial contamination.  Wash hands with soap after having contact with pets, pet feces and dirty surfaces. What can public health agencies do to prevent, control, reduce or eliminate campylobacteriosis?  Adopt and implement a national surveillance program using interactive communication from 'farm to fork'.  Establish networks between states and countries to share new information on Campylobacter.  Conduct research on better methods to prevent infection in chickens and other animals. The Ministry of Agriculture and similar agencies abroad, such as the U.S. Department of Agriculture may be appropriate for conducting such research endeavors.  Adopt codes of practices for farmers, poultry handlers, householders and other stakeholders on ways to reduce, eliminate or prevent contaminated meat from reaching the consumer.

References 1. Christian, J and Greger, J. Nutrition for Living. Benjamin/Cummings Publishing Company, Fourth Edition, 1994. 2. U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, Foodborne Pathogenic Microorganisms and Natural Toxins Handbook, The Bad Bug Book. 3. Jay J. M. Modern Food Microbiology. Aspen Publications, Sixth Edition, 2000. 4. Pattron, D. Recent Research in Public Heath. Scientific Publishers. 2004.





About the author:

Dr Pattron is a Public Health Scientist in the Ministry of Health, Trinidad, West Indies.