A Rare but Vaccine-Preventable Bacterial Infection
Diphtheriais a bacterial infection that commonly affects the nose and throat.
A characteristic sign of a diphtheria infection is a thick, hard, grayish coating inside your throat.
The widespread use of diphtheria vaccines has reduced the incidence of the disease worldwide.
Between 2017 and 2022, the number of cases reported annually has hovered between around 8,000 and 23,000.
Diphtheria can start similarly to a normal respiratory infection with mild flu-like symptoms.
Bleeding will occur if trying to remove or scrape off the dense coating.
Another hallmark is swollen lymph nodes in the neck (calledcervical lymphadenopathy).
This symptom can become so severe as to create a “bull’s neck” appearance.
Without treatment, symptoms of diphtheria will usually last one to two weeks.
However, people may experience complications for weeks or months after the initialacuteinfection.
Approximately 20% to 40% of people with cutaneous diphtheria will develop respiratory diphtheria.
Complications of Diphtheria
Diphtheria can become serious if it spreads (disseminates) beyond the respiratory tract.
Generally, the more toxins released, the sicker a person will be.
A fatal dose in humans is about 0.1 micrograms (g) of toxin per kilogram of body weight.
Death is most commonly the result ofnecrosis(tissue death) of the heart or liver.
This is referred to as fomite transmission.
Respiratory diphtheria is more common during the winter and spring.
Travelers toendemicareas (areas where a disease is common) are vulnerable to infection.
In most cases, diphtheria can only be spread by a person who is sick.
Without treatment, that person is infectious for two to six weeks.
Asymptomaticcarriers can also spread the infection.
These are people who have been infected but show no signs of the disease.
Asymptomatic carriers are usually those who have been vaccinated.
How Is Diphtheria Diagnosed?
The sample will be cultured in a lab to detectCorynebacterium diphtheriaand the toxins it produces.
Other tests will be ordered to characterize the severity of the infection and check for possible complications.
How Diphtheria Is Treated
Diphtheria is treated with an antitoxin that helps neutralize diphtheria toxin.
It is administered in a hospital byintravenous (IV) infusion.
The person would need to be isolated from others to prevent the spread of infection.
In addition to the antitoxin, theantibioticserythromycin or penicillin would be delivered intravenously.
People who have trouble breathing may requireintubationand amechanical ventilator.
This usually occurs 48 hours after receiving the diphtheria antitoxin and starting antibiotic treatment.
Diphtheria is anotifiable disease.
This means that public health officials will contact you and ask questions to help determine how you got infected.
People who have recovered from diphtheria are required to get the diphtheria vaccine.
Getting diphtheria doesn’t protect you from infection for the rest of your life.
Only diphtheria vaccination confers long-lasting immune protection.
Symptoms include difficulty breathing and a thick, gray coating in the upper respiratory tract.
World Health Organization.Diphtheria reported cases and incidence.
doi:10.7759/cureus.35769
Centers for Disease Control and Prevention.Signs and symptoms: respiratory diphtheria.
Centers for Disease Control and Prevention.Diphtheria | Causes and Transmission.
Centers for Disease Control and Prevention.Manual for the Surveillance of Vaccine-Preventable Diseases.
1964;120(6):1007-1018. doi:10.1084/jem.120.6.1007.
Pappenheimer AM.The diphtheria bacillus and its toxin: a model system.Journal of Hygiene.
1984;93(03):397-404. doi:10.1017/s0022172400064998.
Wilson IE, Menson EN.Cutaneous Diphtheria.
New England Journal of Medicine.
2018;378(13):e17.
doi:10.1056/nejmicm1701825
World Health Organization.Immunization, Vaccines and Biologicals: Diphtheria.
