Diphtheria: How It Spreads and Ways to Protect Yourself.

Diphtheria: Causes, Symptoms, Prevention and Treatment

What is Diphtheria?

Diphtheria is a highly contagious bacterial infection caused by Corynebacterium diphtheriae. It primarily affects the mucous membranes of the throat and nose but can also impact the skin and other organs. If left untreated, diphtheria can lead to serious complications, including heart failure, paralysis and respiratory distress.

Causes and Transmission of Diphtheria:

Diphtheria is a serious bacterial infection caused by Corynebacterium diphtheriae. It primarily affects the mucous membranes of the respiratory system but can also infect the skin. This disease, though rare in many developed countries due to widespread vaccination programs, remains a significant public health concern in regions with low immunization coverage.

Causes of Diphtheria:

The primary cause of diphtheria is the bacterium Corynebacterium diphtheriae, which produces a toxin responsible for most of the disease's symptoms. There are four biotypes of C. diphtheriae—gravis, mitis, intermedius, and belfanti—each capable of producing the diphtheria toxin. The toxin leads to tissue damage and the formation of a thick, grayish pseudomembrane in the throat, which can obstruct breathing and cause severe complications.

Several factors contribute to the risk of diphtheria infection, including:

★ Lack of Immunization: Unvaccinated individuals or those with incomplete vaccination schedules are at the highest risk.

★ Crowded or Unsanitary Living Conditions: The bacteria spread more easily in densely populated areas with poor hygiene.

★Weakened Immune System: People with compromised immune defenses are more susceptible.

★ Travel to Endemic Areas: Visiting regions with low vaccination coverage increases the risk of exposure.

Transmission of Diphtheria:

Diphtheria is highly contagious and spreads through direct or indirect contact with an infected person. The primary modes of transmission include:

● Airborne Droplets:

Diphtheria bacteria spread through respiratory droplets expelled when an infected person coughs, sneezes, or talks. Individuals in close proximity to an infected person can inhale these droplets and become infected.

● Direct Contact:

Touching sores or wounds of an infected individual can lead to skin diphtheria, a less common but still serious form of the disease.

● Contaminated Objects (Fomites):

The bacteria can survive on surfaces such as clothing, utensils, and personal items. Contact with contaminated objects and then touching the mouth, nose, or eyes can facilitate infection.

● Asymptomatic Carriers:

Some individuals carry C. diphtheriae without showing symptoms but can still spread the bacteria to others, posing a hidden risk of transmission.

Symptoms of Diphtheria:

The symptoms usually appear within 2 to 5 days after exposure to the bacteria. Early diagnosis and treatment are crucial to prevent serious health risks.

Common Symptoms of Diphtheria:

► Thick Grayish Coating in the Throat:

One of the hallmark signs of diphtheria is the formation of a thick, grayish-white membrane in the throat, tonsils, and nasal passages. This coating can obstruct breathing and make swallowing difficult.

► Sore Throat and Hoarseness:

People infected with diphtheria often experience severe throat pain and hoarseness, making it difficult to speak or swallow properly.

► Swollen Lymph Nodes (Bull Neck):

The infection may cause swelling of the lymph nodes in the neck, leading to a characteristic “bull neck” appearance due to significant inflammation.

► Difficulty Breathing:

As the thick membrane spreads, it can block the airways, leading to breathing difficulties and even respiratory failure in severe cases.

► Fever and Chills:

Mild to moderate fever (usually below 102°F or 38.9°C) accompanied by chills is common in diphtheria patients.

► Fatigue and Weakness:

Patients may feel extreme fatigue, general body weakness, and lethargy due to the toxin released by the bacteria.

► Nasal Discharge:

In nasal diphtheria, symptoms include a runny nose with thick, foul-smelling, blood-streaked discharge. This form is more common in young children.

Severe and Rare Symptoms:

If left untreated, diphtheria can cause life-threatening complications, including:

◆ Heart Complications (Myocarditis):

Diphtheria toxin can damage the heart muscles, leading to irregular heartbeats and heart failure in severe cases.

◆ Nerve Damage:

The toxin may also affect the nervous system, causing muscle weakness, paralysis, and difficulty in movement, particularly in the arms and legs.

◆ Breathing Failure:

Severe airway obstruction can lead to complete respiratory failure, which can be fatal if not treated immediately.

◆ Shock and Organ Failure:

In some cases, diphtheria can lead to septic shock, where the body’s organs start to fail due to severe infection.

Complications of Diphtheria:

If untreated, diphtheria can lead to severe complications such as:

● Myocarditis (heart inflammation).

● Nerve damage and paralysis.

● Pneumonia and lung infections.

● Airway obstruction, leading to respiratory failure.

Diagnosis of Diphtheria:

The diagnosis of diphtheria involves a combination of clinical evaluation, laboratory testing, and differential diagnosis to rule out other conditions with similar symptoms.

Clinical Evaluation:

A healthcare provider will initially assess the patient’s symptoms and medical history. Common signs and symptoms of diphtheria include:

★ Sore throat and difficulty swallowing.

★ Thick, grayish membrane covering the throat and tonsils.

★ Swollen lymph nodes in the neck (bull neck appearance).

★ Fever and chills.

★ Hoarseness or difficulty breathing in severe cases.

Given the severity of diphtheria, doctors may begin treatment based on clinical suspicion before laboratory confirmation.

Laboratory Tests:

Several laboratory methods are used to confirm the presence of Corynebacterium diphtheriae:

► Throat Swab Culture:

• A sample is collected from the throat, tonsils, or nasal passages.
• The sample is cultured on special media, such as tellurite or Loeffler’s medium, to promote bacterial growth.
• If Corynebacterium diphtheriae is present, it forms characteristic colonies that aid in identification.

► Toxin Detection:

• The Elek test is used to detect diphtheria toxin production.
• Polymerase Chain Reaction (PCR) can also identify the toxin-producing genes of the bacteria, offering a more rapid and specific result.

► Blood Tests:

• Complete blood count (CBC) may show signs of infection.
• Serological tests can detect antibodies against the diphtheria toxin, though they are not commonly used for diagnosis.

Differential Diagnosis:

Because diphtheria symptoms can resemble those of other conditions, it is important to distinguish it from:

● Streptococcal pharyngitis (strep throat).

● Infectious mononucleosis.

● Vincent’s angina (trench mouth).

● Oral candidiasis (thrush).

● Epiglottitis.

Prevention of Diphtheria:

Diphtheria spreads through respiratory droplets from an infected person and can cause severe complications, including breathing difficulties, heart failure, and nerve damage. However, diphtheria is largely preventable through vaccination and proper hygiene practices.

◆ Vaccination:

Vaccination is the most effective way to prevent diphtheria. The diphtheria vaccine is typically combined with other vaccines, such as:

★ DTP (Diphtheria, Tetanus, and Pertussis) for children.

★ Tdap (Tetanus, Diphtheria, and Pertussis) for adolescents and adults.

★ Td (Tetanus and Diphtheria) booster shots every 10 years for continued immunity.

It is essential to follow the recommended vaccination schedule to maintain immunity against diphtheria throughout life.

◆ Good Hygiene Practices:

Since diphtheria spreads through respiratory droplets, maintaining good hygiene can reduce the risk of infection. Key hygiene measures include:

★ Frequent Handwashing: Washing hands with soap and water helps eliminate bacteria.

★ Covering Mouth and Nose: Sneezing or coughing into a tissue or elbow prevents the spread of droplets.

★ Avoiding Close Contact: Staying away from infected individuals can help prevent transmission.

◆ Early Diagnosis and Treatment:

Prompt identification and treatment of diphtheria cases are crucial to preventing the spread. If someone exhibits symptoms such as a sore throat, fever, or a thick grayish membrane in the throat, they should seek immediate medical attention. Early treatment with antitoxins and antibiotics can prevent complications and transmission to others.

◆ Quarantine and Isolation:

Patients diagnosed with diphtheria should be isolated until they are no longer contagious. This minimizes the risk of spreading the infection to others. Close contacts of infected individuals should also receive a booster vaccine if they are not up to date on their immunizations.

◆ Public Awareness and Education:

Educating communities about diphtheria prevention is vital. Public health campaigns should focus on:

★ The importance of vaccination.

★ Recognizing early symptoms.

★ Practicing proper hygiene.

Raising awareness can encourage timely vaccinations and reduce the spread of the disease.

Treatment of Diphtheria:

The treatment of diphtheria involves a combination of antitoxin therapy, antibiotics, supportive care, and preventive measures.

► Administration of Diphtheria Antitoxin:

The first and most crucial step in treating diphtheria is the administration of diphtheria antitoxin. This antitoxin neutralizes the toxin produced by Corynebacterium diphtheriae before it binds to body tissues. Since the antitoxin does not reverse the effects of the toxin already bound to tissues, early administration is vital to prevent severe complications such as myocarditis and neurological damage. A skin test is often performed before administering the antitoxin to check for allergic reactions.

► Antibiotic Therapy:

Antibiotics are used to eradicate the Corynebacterium diphtheriae bacteria, thereby preventing further toxin production and transmission. The commonly used antibiotics include:

● Erythromycin (orally or intravenously) for 14 days.

● Penicillin G (intramuscularly or intravenously) followed by oral penicillin for a total duration of 14 days.

Patients are usually required to undergo follow-up cultures after completing antibiotic therapy to ensure complete bacterial eradication.

► Supportive Care:

Since diphtheria can cause complications such as respiratory distress and heart problems, supportive care is essential. This includes:

●Airway Management: Patients with airway obstruction may require intubation or a tracheostomy to maintain adequate breathing.

● Fluids and Nutrition: Patients with difficulty swallowing due to throat inflammation may require intravenous fluids and nutritional support.

● Cardiac Monitoring: Since diphtheria can cause myocarditis (inflammation of the heart muscle), continuous monitoring of heart function is recommended.

► Isolation and Infection Control:

Diphtheria is highly contagious, spreading through respiratory droplets. Infected individuals should be isolated until they are no longer contagious. Proper hygiene and disinfection of surfaces help prevent the spread of infection. Healthcare workers handling diphtheria cases should follow strict infection control measures, including wearing protective gear.

► Vaccination and Preventive Measures:

The best way to prevent diphtheria is through vaccination. The diphtheria toxoid vaccine is part of the DTaP (diphtheria, tetanus, and pertussis) vaccine for children and the Td (tetanus-diphtheria) booster for adults. Close contacts of infected individuals should receive prophylactic antibiotics and a booster vaccine if necessary.

Conclusion:

Diphtheria is a preventable but potentially fatal disease. Early vaccination, proper hygiene, and prompt medical care are essential in controlling its spread and reducing complications. If you or someone around you shows symptoms of diphtheria, seek medical attention immediately to prevent serious health risks.