Rockingham County Health and Human Services
Felissa Ferrell
Director of Health and Human Services
Felissa Ferrell
Director of Social Services
Susan Young, BSN,RN
Interim Health Director

Rockingham County Seal
Communicable Disease


Foodborne illness (also foodborne disease and colloquially referred to as food poisoning) is any illness resulting from the consumption of food that is contaminated by pathogenic bacteria, viruses, or parasites.



Foodborne illness usually arises from improper handling, preparation, or food storage. Good hygiene practices before, during, and after food preparation can reduce the chances of contracting an illness. There is a consensus in the public health community that regular hand-washing is one of the most effective defenses against the spread of foodborne illness. The action of monitoring food to ensure that it will not cause foodborne illness is known as food safety. Foodborne disease can also be caused by a large variety of toxins that affect the environment. For foodborne illness caused by chemicals, see Food contaminants. Foodborne illness can also be caused by pesticides or medicines in food and naturally toxic substances like poisonous mushrooms or reef fish.


Common Foodborne Illness
  • Campylobacter jejuni
  • Clostridium perfringens 
  • Salmonella spp. – its S. typhimurium infection is caused by consumption of eggs or poultry that are not adequately cooked
  • Salmonella Escherichia coli O157:H7 enterohemorrhagic (EHEC) which causes hemolytic-uremic syndrome 
  • Bacillus cereus
  • Listeria monocytogenes  
  • Shigella spp.
  • Staphylococcus aureus
  • Streptococcus
  • Vibrio cholerae, including O1 and non-O1
  • Vibrio parahaemolyticus
  • Vibrio vulnificus
  • Yersinia enterocolitica
  • Yersinia pseudotuberculosis 

In addition to disease caused by direct bacterial infection, some foodborne illnesses are caused by exotoxins which are excreted by the cell as the bacterium grows. Exotoxins can produce illness even when the microbes that produced them have been killed. Symptoms typically appear after 24 hours depending on the amount of toxin ingested. 

  • Clostridium botulinum 
  • Clostridium perfringens
  • Staphylococcus aureus
  • Bacillus cereus 

Viral infections make up perhaps one third of cases of food poisoning in developed countries. In the US, more than 50% of cases are viral and noroviruses are the most common foodborne illness, causing 57% of outbreaks in 2004. Foodborne viral infection are usually of intermediate (1–3 days) incubation period, causing illnesses which are self-limited in otherwise healthy individuals, and are similar to the bacterial forms described above.

  • Enterovirus
  • Hepatitis A is distinguished from other viral causes by its prolonged (2–6 week) incubation period and its ability to spread beyond the stomach and intestines, into the liver. It often induces jaundice, or yellowing of the skin, and rarely leads to chronic liver dysfunction. The virus has been found to cause the infection due to the consumption of fresh-cut produce which has fecal contamination. 
  • Norovirus 
  • Rotavirus 

Most foodborne parasites are zoonoses.

  • Platyhelminthes:
    • Diphyllobothrium sp.
    • Nanophyetussp.
    • Taenia saginata
    • Taenia solium 
    • See also: Tapeworm and Flatworm
  • Nematode:
    • Anisakis sp.
    • Ascaris lumbricoides
    • Eustrongylides sp.
    • Trichinella spiralis
    • Trichuris trichiura
  • Protozoa:
    • Acanthamoeba and other free-living amoebae
    • Cryptosporidium parvum
    • Cyclospora cayetanensis
    • Entamoeba histolytica
    • Giardia lamblia 
Natural toxins

Several foods can naturally contain toxins, many of which are not produced by bacteria. Plants in particular may be toxic; animals which are naturally poisonous to eat are rare. In evolutionary terms, animals can escape being eaten by fleeing; plants can use only passive defenses such as poisons and distasteful substances, for example capsaicin in chili peppers and pungent sulfur compounds in garlic and onions. Most animal poisons are not synthesised by the animal, but acquired by eating poisonous plants to which the animal is immune, or by bacterial action.

  • Alkaloids
  • Ciguatera poisoning
  • Grayanotoxin (honey intoxication)
  • Mushroom toxins
  • Phytohaemagglutinin (red kidney bean poisoning; destroyed by boiling)
  • Pyrrolizidine alkaloids
  • Shellfish toxin, including paralytic shellfish poisoning, diarrhetic shellfish poisoning, neurotoxic shellfish poisoning, amnesic shellfish poisoning and ciguatera fish poisoning
  •  Scombrotoxin
  • Tetrodotoxin (fugu fish poisoning)
  • Some plants contain substances which are toxic in large doses, but have therapeutic properties in appropriate dosages.
  • Foxglove contains cardiac glycosides
  • Poisonous hemlock (conium) has medicinal uses.

The delay between consumption of a contaminated food and the appearance of the first symptoms of illness is called the incubation period. This ranges from hours to days (and rarely months or even years, such as in the case of Listeriosis or Creutzfeldt-Jacob disease), depending on the agent, and on how much was consumed. If symptoms occur within 1–6 hours after eating the food, it suggests that it is caused by a bacterial toxin or a chemical rather than live bacteria.


The long incubation period of many foodborne illnesses tends to cause sufferers to attribute their symptoms to "stomach flu".

During the incubation period, microbes pass through the stomach into the intestine, attach to the cells lining the intestinal walls, and begin to multiply there. Some types of microbes stay in the intestine, some produce a toxin that is absorbed into the bloodstream, and some can directly invade the deeper body tissues. The symptoms produced depend on the type of microbe.


Infectious dose

The infectious dose is the amount of agent that must be consumed to give rise to symptoms of foodborne illness, and varies according to the agent and the consumer's age and overall health. In the case of Salmonella a relatively large inoculum of 1 million to 1 billion organisms is necessary to produce symptoms in healthy human volunteers, as Salmonellae are very sensitive to acid. An unusually high stomach pH level (low acidity) greatly reduces the number of bacteria required to cause symptoms by a factor of between 10 and 100.



Rockingham County has a Multi-disciplinary team always ready to investigate any communicable disease outbreaks within the county.  This team consists of nurses, public information officer, environmental health specialists, lab technicians and administrative staff.

Environmental Health Director
Environmental Health Specialist
Environmental Health Programs Coordinator
| , MO
Contact Us  |  Site Map  
Rockingham County Health and Human Services
371 NC 65 Wentworth, North Carolina 27375 | Phone: 336-342-8140 | Fax: 336-342-8356 | Contact Us
Site Map  -  Non-Discrimination Policy  -  Notice of Privacy Practices  -  Aviso De Politica De Privacidad
Powered by MunicipalCMS
E-notify RSS Feeds Twitter Facebook