Introduction

Worldwide, bacterial gastroenteritis is mostly caused by the genus Campylobacter. The gastrointestinal system is the primary site of infection for Campylobacter, sometimes referred to as campylobacteriosis, which causes symptoms including fever, diarrhoea and stomach discomfort. While it affects people of all ages, adults, especially those with specific risk factors, can be seriously harmed by this illness.¹

Because of their flagella (membrane extensions, like a tail), Campylobacter bacteria have a spiral form, are motile, and are Gram-negative (meaning they cannot be seen with a Gram stain). Although this genus has a number of species, Campylobacter jejuni and Campylobacter coli are the most often linked to human disease. These bacteria are commonly found in the intestines of animals, especially chickens, and they flourish in settings with low oxygen levels.

Although the bacteria known as Campylobacter are sensitive to their surroundings, they are quite skilled at living in their animal hosts. Humans can contract the disease mostly from animals by direct touch, cross-contamination during food preparation or ingestion of contaminated food or drink. Unpasteurised milk, untreated water and undercooked or raw chicken are specifically linked to the bacterium.

Campylobacteriosis is a serious public health hazard. It is one of the most common bacterial causes of gastroenteritis in many affluent nations. For example, it's estimated that every year in the United States, Campylobacter causes around 1.5 million infections. The true figure is likely higher due to incorrect diagnoses and underreporting.²

The importance of a Campylobacter infection in adults goes beyond only gastrointestinal distress. While many healthy individuals recover without facing substantial repercussions, some populations are more vulnerable to more dire consequences. These involve:

• People with compromised immune systems: Chemotherapy patients, HIV/AIDS patients, and patients using immunosuppressive drugs are more vulnerable to serious infection
• Senior citizens: Complications and increased vulnerability might result from immunological deterioration associated with ageing
• Individuals who suffer from chronic illnesses: Illnesses such as diabetes, liver disease and inflammatory bowel disease can make an infection worse

Understanding campylobacter

These bacteria are found in microaerophilic settings, which means that they grow at lower oxygen concentrations than those present in the atmosphere. Usually, they are located in the digestive systems of animals, especially birds. Although certain Campylobacter species are more delicate than others and are susceptible to environmental stressors, including high temperatures, acidic environments and drying out, they are skilled at living in particular niches where they may multiply.³

Of the several Campylobacter species, two are principally accountable for human infections:

1. Campylobacter jejuni is the most frequent species that infects people. Most gastroenteritis cases linked to Campylobacter are caused by it. Poultry is frequently linked to C. jejuni, and it is a significant reservoir. Eating undercooked or incorrectly handled infected chicken or turkey is usually the cause of infection
2. Campylobacter coli: This species is important even though it is less common than C. jejuni. It is also connected to other animals like pigs and poultry. Similar to C. jejuni, C. coli infections are brought on by consuming tainted food or water

Humans are typically exposed to the Campylobacter bacteria through direct or indirect contact with diseased animals as well as through the consumption of contaminated food or water. Important transmission channels consist of:

• Food contamination: Eating infected food, especially raw or undercooked poultry, is the most common way for the infection to spread. Unpasteurised milk and tainted water can also contain Campylobacter. The germs can also spread through cross-contamination in the kitchen, which occurs when raw chicken and other foods are prepared on the same cutting board or cutlery without being properly cleaned
• Water contamination: Infection can result from drinking or recreational water tainted with Campylobacter. This is more frequent during outdoor activities where natural water sources are utilised without sufficient purification or in places with poor water treatment facilities
• Animal contact: The germs can be spread by direct contact with infected animals, especially pets or cattle. Those who work in agriculture, veterinary medicine or animal care are particularly at risk from this. Many animals have Campylobacter in their intestines, and mishandling animal excrement can contaminate hands and surfaces
• Person-to-person: Although less frequent, the faecal-oral route can transmit an infection from one person to another, especially in environments with inadequate hygiene standards or between persons who are in close proximity, including family members or healthcare professionals

Comprehending these pathways of transmission is pivotal to executing efficacious preventative measures, such as endorsing appropriate food handling and cooking techniques, guaranteeing the availability of uncontaminated water and fostering optimal personal cleanliness.

Risks associated with campylobacter infection

People with weakened immune systems:

Compared to healthy persons, those with compromised immune systems are more susceptible to Campylobacter infections, which can cause more severe and persistent sickness.³ This group consists of:

• Patients with weakened immune systems: People on immunosuppressive medications or undergoing chemotherapy, such as organ transplant patients, are more vulnerable to infection since their bodies are less able to fight it off. Other reasons involve
• Consumption of undercooked poultry and unpasteurised dairy products⁴
• Environmental and occupational risks

Symptoms of campylobacter infection

A Campylobacter infection, also known as campylobacteriosis, can cause a variety of symptoms, ranging from minor gastrointestinal distress to serious disease. For an early diagnosis and suitable treatment, it is essential to comprehend the usual symptoms, severity, duration and potential consequences of a Campylobacter infection.¹

Common Symptoms:

• Diarrhoea (frequently bloody): The classic sign of a Campylobacter infection is diarrhoea. Stools may be loose, watery and come with mucus or blood in them. This happens as a result of the bacteria causing intestinal irritation
• Cramps and abdominal pain: These are two typical concomitant (associated) symptoms. These are usually confined to the lower abdomen and can range in severity from little discomfort to excruciating agony
• Fever and nausea: Fever is frequently associated with chills and is a common symptom of Campylobacter infection. Vomiting and nausea are also possible, which adds to the misery all around

Diagnosis of campylobacter infection

Clinical evaluation

A comprehensive evaluation of symptoms and patient history is usually the first step in the diagnostic procedure. Medical professionals ask about any recent travel, exposure to tainted food or water and any gastrointestinal symptoms the patient may be experiencing, including nausea, diarrhoea, stomach discomfort and fever. This data aids in directing additional testing and assessment.¹

Laboratory tests

Stool culture is the gold standard diagnostic test for Campylobacter infection. A small sample of stool is collected and cultured in a laboratory to isolate and identify the bacteria. Campylobacter species grow slowly and require specific culture conditions, such as microaerophilic conditions and selective media containing antibiotics to suppress the growth of other bacteria. Once grown, the bacteria are identified using biochemical tests or molecular methods.

Polymerase chain reaction (PCR) tests are increasingly used to detect Campylobacter DNA in stool samples with high sensitivity and specificity. PCR tests can provide rapid results and are particularly useful in cases where traditional culture methods may yield false negatives due to the fastidious nature of Campylobacter bacteria (meaning the bacteria require very specific conditions to thrive) or prior antibiotic use by the patient.

Making an accurate diagnosis of Campylobacter infection is crucial for starting the right course of treatment, keeping an eye out for any problems in the patient, and putting public health measures in place to stop the illness from spreading. To accurately and quickly diagnose campylobacteriosis, medical professionals rely on clinical examination, laboratory testing and a broad awareness of differential diagnoses.

Treatment and care for campylobacter infection

In order to manage symptoms, handle complications and avoid serious consequences, treating campylobacteriosis, also known as campylobacter infection, entails a combination of self-care practices and medical treatments. Good management reduces the chance of transmission and guarantees a speedy recovery.

Home remedies and self-care

• Rest and hydration: Staying well hydrated is essential for treating a Campylobacter infection at home. It is critical to drink lots of fluids since vomiting and diarrhoea can cause severe fluid loss. You can restore lost electrolytes with the use of oral rehydration solutions (ORS). Additionally, rest is essential to the body's ability to heal.
• Dietary advice (bland diet): A bland diet might ease gastrointestinal discomfort during the acute stage of the sickness. Suggested meals include:
  • Clear broths
  • Toast, bananas, applesauce and plain rice

Dairy, fatty meals and spicy foods should be avoided since they might aggravate symptoms.

Medical treatment

• Antibiotic therapy: People with compromised immune systems, the elderly or pregnant women are among the groups most at risk of problems, and antibiotics are often only used in severe instances.⁵ Antibiotics that are most often used include:
  • Zithromycin
  • Erythromycin
  • Ciprofloxacin (however, there is a worry about increasing resistance)

In severe situations, antibiotics can help shorten the length of symptoms and minimise bacterial shedding; however, they are usually not required for moderate infections.

• Handling hospitalisation and severe cases: Hospitalisation may be necessary in severe instances of Campylobacteriosis, especially if there is severe dehydration or other consequences such as bacteraemia. In a medical facility, patients might get:
  • Intravenous fluid administration for dehydration
  • Replenishment of electrolytes
  • Close observation for any indications of problems
  • Therapy with antibiotics if necessary

Prevention of complications

Follow-up care for severe or persistent symptoms: In order to guarantee full healing and spot any possible consequences, persistent or severe symptoms need to be followed up. This might consist of:

• Ongoing feeding and hydration assistance
• Keeping an eye out for symptoms of Guillain-Barré syndrome or reactive arthritis, which might arise following the first illness
• Further laboratory testing or imaging may be necessary if symptoms point to serious colitis or an abscess

Summary

Campylobacter, mainly C. jejuni and C. coli, is one of the leading causes of bacterial gastroenteritis worldwide. It spreads primarily through undercooked poultry, unpasteurised milk, contaminated water, and animal contact. Adults with weakened immune systems, chronic illnesses, or advanced age face higher risks of severe illness.

Typical symptoms include diarrhoea (often bloody), abdominal cramps, fever, nausea, and vomiting. Diagnosis is based on clinical history and stool testing, with stool culture and PCR being the main methods.

Most cases resolve without antibiotics, and treatment focuses on rest, hydration, oral rehydration solutions, and a bland diet. Antibiotics (e.g., azithromycin, erythromycin) are reserved for severe or high-risk cases. Hospitalisation may be needed for complications such as severe dehydration or bacteraemia. Rare long-term effects include Guillain-Barré syndrome and reactive arthritis.

Prevention relies on safe food handling, proper cooking of poultry, access to clean water, and good hygiene practices.