Diphtheria

The good news is that diphtheria is a preventable disease. The DTaP vaccine is recommended for all children at 2, 4, 6, and 15-18 months of age, with a booster dose at 4-6 years of age.

Jul 05, 2023

Overview

Diphtheria, also pronounced (dif-THEER-e-uh), is a serious infectious disease caused by the bacterium Corynebacterium diphtheriae. The bacterium produces a toxin that can damage the heart, nerves, and other organs. Diphtheria is spread through respiratory droplets produced when an infected person coughs or sneezes. It can also be spread through contact with infected skin lesions.

In the past, diphtheria was a common and deadly disease. However, thanks to vaccination, diphtheria has become rare in developed countries. In the United States, for example, only a handful of cases of diphtheria have been reported in recent years.

However, diphtheria is still a serious threat in some parts of the world. In 2022, over 50,000 cases of diphtheria were reported worldwide, and over 5,000 people died from the disease.

The good news is that diphtheria is a preventable disease. The DTaP vaccine is recommended for all children at 2, 4, 6, and 15-18 months of age, with a booster dose at 4-6 years of age. Adults should also get a Tdap vaccine every 10 years.

How is diphtheria spread?

Diphtheria is primarily spread through respiratory droplets, which are tiny particles of moisture containing the bacteria Corynebacterium diphtheriae. When an infected person coughs, sneezes, or even talks, these droplets are released into the air. If a susceptible person breathes in these contaminated droplets, they can become infected with the bacteria and develop diphtheria.

In addition to direct person-to-person transmission, diphtheria can also spread indirectly through contact with objects or surfaces contaminated with respiratory secretions from an infected individual. For example, if an infected person touches their mouth or nose and then touches an object like a doorknob, table, or utensil, the bacteria can be left behind. If another person touches the contaminated surface and then touches their mouth, nose, or eyes, they may become infected.

Diphtheria is highly contagious, especially in crowded or poorly ventilated environments, such as schools, daycare centres, and refugee camps. It can spread easily among individuals in close proximity, particularly in areas with low vaccination rates or limited access to healthcare.

Signs and Symptoms

The signs and symptoms of diphtheria can vary depending on the site of infection and the severity of the disease. It typically takes around 2 to 5 days for symptoms to appear after exposure to the bacteria Corynebacterium diphtheriae. Mild cases may only cause a sore throat, fever, and fatigue. More severe cases can lead to a thick, grayish-white membrane that forms in the throat, making it difficult to breathe.

Sore throat
Fever
Swollen lymph nodes in the neck
Weakness
Chills
Headache
Muscle pain
Loss of appetite
Difficulty breathing
Nausea and vomiting
Skin lesions

Complications

Diphtheria can lead to various complications, especially if left untreated or if the infection is severe. The bacteria Corynebacterium diphtheriae produces a potent toxin that can affect different organs and systems in the body. Here are some of the potential complications associated with diphtheria:

Sore Throat: Diphtheria often begins with a mild sore throat that gradually worsens over time. The throat may become red and swollen.
Thick Membrane Formation: One of the hallmark features of diphtheria is the formation of a thick grayish-white membrane or coating on the back of the throat and tonsils. This membrane can extend to the nose, making it difficult to breathe or swallow.
Difficulty Breathing and Swallowing: As the membrane expands, it can obstruct the airway, leading to breathing difficulties and a high-pitched sound during inhalation, known as stridor. Swallowing becomes painful and challenging.
Fever: Diphtheria can cause a moderate to high fever, typically above 38°C (100.4°F).
Swollen Neck Glands: The lymph nodes in the neck may become enlarged and tender due to the body's immune response to the infection.

In severe cases or when the toxin produced by the bacteria spreads throughout the body, diphtheria can lead to more serious complications, including:

Myocarditis: The toxin can damage the heart muscle, leading to inflammation and potentially causing heart failure or other cardiac problems.
Neuritis: Nerve damage may occur, resulting in paralysis or weakness, particularly in the muscles of the head and neck.

Kindly note that individuals who have been infected with the bacteria can be carriers without showing any symptoms. These carriers can still spread the disease to others, making it crucial to maintain good hygiene practices and follow preventive measures, even in the absence of obvious symptoms.

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Diagnosis

Diagnosing diphtheria typically involves a combination of clinical evaluation, laboratory tests, and throat cultures. Here are the common diagnostic methods used:

Clinical Evaluation: A healthcare professional will examine the patient's symptoms, including the presence of a membrane in the throat, difficulty breathing or swallowing, and swollen neck glands. This evaluation helps in assessing the likelihood of diphtheria.
Throat Culture: A sample from the back of the throat, including the membrane if present, is collected using a swab. This sample is then sent to a laboratory for analysis. The laboratory tests involve culturing the bacteria and identifying its presence. This test confirms the diagnosis of diphtheria and can also determine the specific strain of the bacteria.
Polymerase Chain Reaction (PCR): PCR tests are increasingly used to detect the genetic material of the bacteria directly from the throat swab. PCR tests are more rapid than traditional culturing methods and can provide quicker results.

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Treatment

Diphtheria requires immediate medical treatment to prevent complications and control the spread of the disease. The treatment generally involves the following:

Diphtheria Antitoxin: Diphtheria antitoxin is a medication derived from the blood of individuals who have developed immunity to the diphtheria toxin. It is administered to neutralize the effects of the toxin produced by the bacteria. The antitoxin is usually given intravenously under medical supervision.
Antibiotics: Antibiotic treatment is necessary to eliminate the bacteria from the body and prevent its further spread. Commonly used antibiotics include penicillin or erythromycin. The course of antibiotics should be completed as prescribed by the healthcare provider, even if the symptoms improve.
Supportive Care: Supportive care plays a crucial role in managing diphtheria. It may include measures to ensure an open airway, such as providing oxygen or performing a tracheostomy if necessary. Additional support, such as intravenous fluids and pain management, may be required.
Isolation and Quarantine: Individuals diagnosed with diphtheria need to be isolated to prevent the spread of the disease. Close contacts may also need to be quarantined and monitored for symptoms.

Prevention

Prevention is essential in controlling diphtheria. Vaccination is the primary method of prevention. The diphtheria vaccine is typically administered as part of the DTaP (diphtheria, tetanus, and pertussis) vaccine series for children, and the Tdap (tetanus, diphtheria, and pertussis) vaccine for adolescents and adults. Maintaining up-to-date vaccination schedules helps to protect individuals and communities from the disease.

In addition to vaccination, practising good hygiene, such as frequent handwashing with soap and water, covering the mouth and nose while coughing or sneezing, and avoiding close contact with infected individuals, can help reduce the risk of transmission.

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Vaccination

Vaccination is a crucial and effective method of preventing diphtheria. The diphtheria vaccine stimulates the immune system to produce protective antibodies that can neutralize the diphtheria toxin and prevent infection. Here are some key points regarding diphtheria vaccination:

Vaccine Types:

DTaP Vaccine: The DTaP vaccine is administered to children in a series of doses. It protects against diphtheria, tetanus, and pertussis (whooping cough). The vaccine contains inactivated or toxoid forms of the diphtheria toxin that cannot cause disease but can elicit an immune response.
Tdap Vaccine: The Tdap vaccine is a booster dose given to adolescents and adults. It provides a combined immunity against diphtheria, tetanus, and pertussis. Tdap is generally recommended for individuals who have completed the childhood DTaP series and need a booster.

Vaccination Schedule:

The diphtheria vaccination schedule typically includes the following doses:

DTaP: The DTaP vaccine is administered as a series of five doses, usually given at 2, 4, and 6 months of age, with booster doses at 15-18 months and 4-6 years of age.
Tdap: The Tdap vaccine is usually given as a single booster dose at the age of 11-12 years. If not received during adolescence, it can be given to adults as a catch-up vaccine.

Vaccine Effectiveness and Duration of Protection:

Diphtheria vaccination provides robust protection against the disease. The vaccine induces the production of antibodies that can neutralize the diphtheria toxin, preventing severe illness and complications. The immunity acquired through vaccination can last for many years, but periodic booster doses are recommended to maintain protection throughout adulthood.

Herd Immunity:

Vaccination against diphtheria not only protects the vaccinated individuals but also contributes to herd immunity. When a significant proportion of the population is vaccinated, it creates a barrier that limits the spread of the disease, protecting those who cannot receive vaccines due to medical conditions or age. High vaccination coverage is crucial in preventing outbreaks and protecting vulnerable populations.

Side Effects:

Diphtheria vaccines are generally safe and well-tolerated. Common side effects, if any, are usually mild and temporary, such as redness, swelling, or soreness at the injection site. Fever, fussiness, or mild allergic reactions can also occur in some cases. Serious side effects are rare.

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Personal Prevention Strategies

In addition to vaccination, there are personal prevention strategies that individuals can adopt to reduce the risk of contracting diphtheria. These strategies are particularly important when travelling to areas with low vaccination coverage or in situations where there may be increased exposure to the bacteria. Here are some key personal prevention strategies for diphtheria:

Maintain Good Hygiene Practices: Regular handwashing with soap and water for at least 20 seconds is crucial in preventing the spread of infectious diseases, including diphtheria. If soap and water are not available, using alcohol-based hand sanitizers can be an effective alternative. Avoid touching your face, especially your mouth, nose, and eyes, as this can introduce bacteria into your system.
Practice Respiratory Etiquette: Cover your mouth and nose with a tissue or your elbow when coughing or sneezing to prevent the release of respiratory droplets containing the bacteria. Properly dispose of used tissues and wash your hands afterwards
Avoid Close Contact with Infected Individuals: Stay away from individuals who have been diagnosed with diphtheria or are suspected to have the infection. Diphtheria is highly contagious, and close contact increases the risk of transmission.
Be Mindful of Environmental Factors: Avoid overcrowded or poorly ventilated areas, as these conditions can facilitate the spread of respiratory infections. If you are in a high-risk environment, such as a healthcare facility or an area with known cases of diphtheria, take extra precautions to minimize exposure.
Stay Up-to-Date with Vaccinations: Ensure that you and your family members receive the recommended diphtheria vaccinations according to the appropriate schedule. Check with your healthcare provider to confirm your vaccination status and discuss any necessary boosters.
Seek Medical Attention: If you experience symptoms such as a sore throat, difficulty swallowing or breathing, or swollen neck glands, seek prompt medical attention. Early diagnosis and treatment are essential in managing diphtheria and preventing complications.

Remember that personal prevention strategies are important not only for protecting yourself but also for safeguarding vulnerable individuals who may be more susceptible to severe diphtheria infections, such as young children, older adults, and those with weakened immune systems.

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