Introduction

Definition of campylobacter infection 

The Campylobacter bacteria is the most common bacterial cause of gastroenteritis (inflammation of the stomach and intestines) in humans.¹ Campylobacter irritates the lining of the stomach and intestines which causes typical gastrointestinal symptoms such as diarrhoea, stomach cramps, nausea, and vomiting. This article will explore the features of these symptoms in greater detail.

General overview of campylobacter

Types of campylobacter bacteria 

There are two main types of campylobacter which cause gastroenteritis in humans, C. Jejuni and C. Coli. Studies show that the type of bacteria has a significant effect on factors such as age, travel and season.

Older people are more likely to be infected with C. Coli, as well as those who have travelled outside of the country.² Infections during the peak season of the infection (summer time) found most infections to be C. Jejuni infections which may be explained by a higher rate of contamination of poultry during that season.² 

Transmission and risk factors 

Contaminated food and water 

Campylobacter lives in the intestines of farm animals such as poultry, cows, pigs, and sheep.¹ Meat is usually contaminated through contact with faeces during slaughtering.¹ The bacteria is then transmitted through meat which isn’t properly cooked (especially chicken) or raw/unpasteurized contaminated milk.^1,3 This is the main cause of campylobacter infection. 

Contamination could also occur through water which contains the bacteria.¹ 

Animal contact 

As well as living in the intestines of the animals above, campylobacter can also be present in domestic animals such as cats and dogs especially animals younger than 6 months.^1,3 Therefore, transmission can occur through contact with these animals.

Studies have shown that owning pets is a significant risk factor for the infection.⁴ Humans can also pass the infection onto animals and these animals can then infect other humans; this particularly happens with young children and puppies and kittens.³  

Person-to-person spread

Although more uncommon, humans can spread the infection to each other through contaminated faeces.⁵  

Common symptoms of campylobacter infection

Symptoms appear 2 to 5 days after contamination with the bacteria.⁵ Initial symptoms before the full development of the infection, known as prodromal symptoms, may be present and last around 1 to 3 days.⁶ These include:⁶

• A high fever
• Shivers 
• Dizziness 
• Body aches 

Those with initial symptoms may have more severe symptoms as the disease progresses.6

Gastrointestinal symptoms

Diarrhoea 

Frequency and consistency 

Campylobacter infection usually presents with enteritis causing large volumes of diarrhoea.⁶ On average, diarrhoea is present for around a week, however, stomach cramps may continue for days to weeks after.⁶ Patients may still be contagious for several weeks after the diarrhoea improves, however, antimicrobial treatment seems to reduce this likelihood.6 

The frequency of diarrhoea is common during the acute phase, where more than 10 stools can occur a day.⁶ 

Diarrhoea is often the only symptom in infants.5  

Presence of blood or mucus 

Diarrhoea may often contain blood or mucus due to the invasion of the bacteria into the lining of the intestines and the subsequent inflammation and damage.^5,6

Abdominal pain and cramps 

Location and severity

The abdomen may feel tender to touch, especially the lower abdomen on both the left and right sides.⁶

Nausea and vomiting 

Common occurrence 

Vomiting isn’t always a symptom of campylobacter infection, however, it may be as the body tries to get rid of the bacteria.

Impact on hydration and nutrition

Vomiting can often lead to dehydration because it causes the body to get rid of essential water and salts.⁵ The NHS describes some of the symptoms of dehydration as:

• Feeling very thirsty 
• Darker urine with a strong smell
• Peeing less
• Dizziness
• A dry mouth
• Sunken eyes

In infants this can look like this: 

• A sunken soft spot on their head
• Crying with no tears
• Being fussy or sleepy 
• Peeing less. Less than 6 wet diapers per day, or in toddlers no urine output for 8 hours⁵

Fever 

Fever may be present with campylobacter infection as the body creates the right conditions to fight the infection. This may range from normal to over 38.9 degrees. A fever may last around a week. 

Symptoms and prognosis

Infection with campylobacter is very contagious so it is common for people to acquire the illness. Fortunately, symptoms in most people will ease within a week with no further complications.⁷  

Those who are immunocompromised, older, or worried about their symptoms should see a doctor to discuss their illness.⁷ 

Symptom onset and duration 

Typical recovery time (1 week) 

Recovery usually takes around 7 days.⁸ 

Prolonged cases and complications

The complications are a fault of the body’s immune system. The antibodies the body produces to fight against campylobacter can react with the child’s body causing reactive arthritis or erythema nodosum.⁵ 

The infection may cause long-term complications such as IBS, arthritis, nerve damage or Guillain-Barre syndrome.⁸ 

Diagnosis of campylobacter infection

Medical history and symptom review 

It is recommended to talk to your doctor if you notice signs of the infection such as:⁸   

• Diarrhoea or vomiting for longer than 2 days 
• Blood in your poo
• A fever higher than 38.9 degrees Celsius 
• Symptoms of dehydration
• Symptoms of Guillain-Barre syndrome such as weakness or tingling in your legs and arms 

Importance of accurate reporting 

Knowing your symptoms as well as risk factors and informing the doctor of these accurately will help them determine which bacteria may be causing your illness. This may be confirmed by tests. 

Laboratory Tests 

• Stool culture

Sending a stool sample to be tested for the presence of campylobacter is the most common test used.⁷  

• Blood tests (in severe cases)

Blood tests may be used if the doctor suspects bacteraemia (the spread of bacteria into the bloodstream) which may be life-threatening.⁷ 

Differential diagnosis

The symptoms of campylobacter infection may be similar to those of other gastrointestinal bacterial infections. These include bacteria such as:

• Salmonella 
• Shigella
• E. coli
• Listeria

Norovirus, which typically causes stomach flu, may be mistaken for campylobacter infection. 

In people who have recently travelled, parasitic causes of diarrhoea may be a more likely explanation.⁶ 

The lower abdominal pain especially on the right may be mistaken for appendicitis.⁶ Inflammatory bowel disease (IBS), Crohn's disease and ulcerative colitis may be causing the bloody diarrhoea.⁶  

Treatment and management

General care 

Hydration 

In healthy patients, treatment focuses on hydration and electrolytes.⁶ Hydration can be given by mouth or with clinical assistance, such as through IV or a tube into the stomach depending on how severe it is.⁶ 

Medical treatment 

Antibiotics 

Indications for use 

Antibiotics are usually only used in high-risk patients including immunocompromised and older patients.⁶ Those with severe illness including a high fever, bloody diarrhoea or bad abdominal pain may also be given antibiotics.⁶ 

Common antibiotics prescribed 

Infections with campylobacter require the use of macrolide antibiotics such as azithromycin, clarithromycin, and erythromycin.⁶ 

Antidiarrheal medications 

Antidiarrheal medications aren’t usually used because they can reduce the ability of the body to get rid of the infection.⁶ 

Use and precautions 

Hospitalisation

Some people with severe symptoms of the infection causing dehydration may be hospitalised for further support and rehydration.

Prevention and control

To prevent the spread of infection, it is recommended that hand washing is done thoroughly using soap and warm water. The NHS recommends this is done: 

• Before preparing, cooking or eating food
• After contact with raw food especially meat 
• After using the bathroom or changing a baby’s nappy
• After interacting with pets  

Furthermore, avoid washing raw chicken to prevent cross-contamination and keep it away from cooked food or raw vegetables.⁹ Avoid drinking water from unknown lakes or rivers or unpasteurized milk.9 

Understanding who may be at increased risk of campylobacter infection may help you to recognize the symptoms quicker. The NHS says those at higher risk are:

• Children under 5
• People over 60
• People having regular contact with animals such as farmers or those working in the meat industry 
• Frequent travellers 

Conclusion

Infections with Campylobacter bacteria are a common cause of gastroenteritis in humans. Illness may be preceded by prodromal symptoms such as a high fever, shivers, or dizziness. Large volumes of diarrhoea and stomach cramps typically follow. Blood or mucus may be present in the stool. It is important to look out for symptoms of dehydration. Understanding the risk factors along with the symptoms may be helpful in determining the bacteria causing the illness.