Diphtheria is a serious bacterial infection caused by Corynebacterium diphtheriae, which primarily affects the mucous membranes of the nose and throat. It can lead to severe complications, including heart and nerve damage, and can be fatal if untreated. Although widespread vaccination has significantly reduced its incidence in many parts of the world, diphtheria remains a concern in areas with low immunization rates.
Causes and Transmission
Diphtheria is caused by toxin-producing strains of Corynebacterium diphtheriae. The bacteria spread through:
- Respiratory droplets (from coughing or sneezing)
- Direct contact with an infected person
- Contaminated objects (e.g., utensils, clothing)
Some individuals may carry the bacteria without showing symptoms (asymptomatic carriers), contributing to its spread.
Types of Diphtheria
- Respiratory Diphtheria โ Affects the throat, nose, and tonsils, forming a thick gray pseudomembrane that can obstruct breathing.
- Cutaneous Diphtheria โ Affects the skin, causing ulcers or sores, often seen in tropical regions.
- Asymptomatic Carrier State โ The person carries the bacteria without symptoms but can still spread it.
Symptoms
Symptoms usually appear 2โ5 days after infection and may include:
- Early Symptoms:
- Sore throat
- Mild fever
- Swollen neck glands (bull neck appearance)
- Advanced Symptoms:
- Thick gray or white membrane covering the throat and tonsils
- Difficulty breathing or swallowing
- Hoarseness
- Weakness and fatigue
If the toxin spreads through the bloodstream, it can cause:
- Myocarditis (heart inflammation)
- Nerve damage (leading to paralysis)
- Kidney failure
- Death (in 5โ10% of cases, higher in untreated patients)
Diagnosis
Diagnosis involves:
- Clinical Examination โ Checking for the characteristic pseudomembrane.
- Throat Swab Culture โ To identify C. diphtheriae.
- Toxin Testing โ To confirm if the strain produces the harmful toxin.
- PCR Testing โ For rapid detection of the bacteria.
Treatment
Immediate treatment is crucial and includes:
- Diphtheria Antitoxin (DAT) โ Neutralizes the toxin; given before lab confirmation in suspected cases.
- Antibiotics โ Such as penicillin or erythromycin to kill the bacteria.
- Supportive Care โ Including airway management if breathing is obstructed.
- Isolation โ To prevent spreading the infection.
Complications
If left untreated, diphtheria can cause:
- Airway obstruction (due to the pseudomembrane)
- Myocarditis (leading to heart failure)
- Neurological issues (nerve damage, paralysis)
- Kidney damage
Prevention
The most effective prevention is vaccination:
- DTaP Vaccine (Diphtheria, Tetanus, and Pertussis) โ Given to children in five doses (2, 4, 6 months, 15โ18 months, and 4โ6 years).
- Tdap/Td Booster โ Recommended for adolescents and adults every 10 years.
Other preventive measures include:
- Maintaining high vaccination coverage in communities.
- Isolating infected individuals until they are no longer contagious.
- Practicing good hygiene (handwashing, covering mouth when coughing).
Global Situation
While diphtheria is rare in countries with high vaccination rates, outbreaks still occur in regions with low immunization coverage, such as parts of Africa, Asia, and Eastern Europe. Travelers to these areas should ensure they are up-to-date with vaccinations.
Conclusion
Diphtheria is a preventable but potentially deadly disease. Vaccination remains the best defense, along with prompt diagnosis and treatment in suspected cases. Public health efforts must continue to ensure widespread immunization to eliminate diphtheria as a global health threat.
