if given early in the illness. moreover, maintenance of electrolyte balance, not antibiotic treatment, is the cornerstone of treatment for campylobacter enteritis. indeed, most patients with this infection have a self-limited illness and do not require antibiotics at all. nevertheless, antibiotics should be used in specific clinical circumstances. these include high fevers, bloody stools, prolonged illness (symptoms that last >1 week), pregnancy, infection with hiv, and other immunocompromised states. prevention some simple food-handling practices can help prevent campylobacter infections. cook all poultry products thoroughly. make sure that the meat is cooked throughout (no longer pink) and any juices run clear. all poultry should be cooked to reach a minimum internal temperature of 165 °f (74 °c). wash hands with soap before preparing food. wash hands with soap after handling raw foods of animal origin and before touching anything else. prevent cross-contamination in the kitchen by using separate cutting boards for foods of animal origin and other foods and by thoroughly cleaning all cutting boards, countertops, and utensils with soap and hot water after preparing raw food of animal origin. do not drink unpasteurized milk or untreated surface water. make sure that people with diarrhea, especially children, wash their hands carefully and frequently with soap to reduce the risk of spreading the infection. wash hands with soap after contact with pet feces. genome the genome of c. jejuni strain nctc11168 was published in 2000, revealing 1,641,481 base pairs (30.6% g+c) predicted to encode 1,654 proteins and 54 stable rna species. the genome is unusual in that virtually no insertion sequences or phage-associated sequences and very few repeat sequences are found. one of the most striking findings in the genome was the presence of hypervariable sequences. these short homopolymeric runs of nucleotides were commonly found in genes encoding the biosynthesis or modification of surface structures, or in closely linked genes of unknown function. the apparently high rate of variation of these homopolymeric tracts may be important in the survival strategy of c. jejuni. the genome was re-annotated in 2007 updating 18.2% of product functions. analysis also predicted the first pathogenicity island in c. jejuni amongst select strains, harbouring the bacteria's type vi secretion system and putative cognate effectors. initial transposon mutagenesis screens revealed 195 essential genes, although this number is likely to go up with additional analysis. natural genetic transformation c. jejuni is naturally competent for genetic transformation. natural genetic transformation is a sexual process involving dna transfer from one bacterium to another through the intervening medium, and the integration of the donor sequence into the recipient genome by homologous recombination. c. jejuni freely takes up foreign dna harboring genetic information responsible for antibiotic resistance. antibiotic resistance genes are more frequently transferred in biofilms than between planktonic cells (single cells that float in liquid media). dna repair in the intestinal environment, bile functions as a defensive barrier against colonization by c. jejuni. when c. jejuni is grown in a medium containing the bile acid deoxycholic acid, a component of bile, the dna of c. jejuni is damaged by a process involving oxidative stress. to survive, c. jejuni cells repair this dna damage by a system employing proteins adda and addb that are needed for repair of dna double-strand breaks. laboratory characteristics characteristic result growth at 25 °c − growth at 35–37 °c + growth at 42 °c + nitrate reduction + catalase test + oxidase test + growth on macconkey agar + motility (wet mount) + glucose utilization − hippurate hydrolysis + resistance to nalidixic acid − resistance to cephalothin + scanning electron micrograph depicting a number of campylobacter jejuni bacteria under light microscopy, c. jejuni has a characteristic "sea-gull" shape as a consequence of its helical form. campylobacter is grown on specially selective "camp" agar plates at 42 °c, the normal avian body temperature, rather than at 37 °c, the temperature at which most other pathogenic bacteria are grown. since the colonies are oxidase positive, they usually only grow in scanty amounts on the plates. microaerophilic conditions are required for luxurious growth. a selective blood agar medium (skirrow's medium) can be used. greater selectivity can be gained with an infusion of a cocktail of antibiotics: vancomycin, polymixin-b, trimethoprim, and actidione (), and growth under microaerophilic conditions at 42 °c.