Diphtheria is an acute infectious disease caused by a toxin produced by the bacterium Corynebacterium diphtheriae (diphtheria bacillus). It primarily attacks the mucous membranes of the throat and larynx, helping less often the nose, skin, or genitals.
Transmission occurs mainly:
by airborne droplets – during coughing, sneezing, talking,
by direct contact with a sick person or carrier (also through contact with discharge from a skin wound),
rarely – through infected animals or heavily contaminated objects.
The incubation period is usually 2–5 days (range 1–10 days).
Who is most at risk?
unvaccinated people or those with an incomplete vaccination cycle,
adults who do not take booster doses,
children <5 years old and people >40 years old – mortality is highest among them, even up to 20%,
travelers going to countries where diphtheria is still endemic,
people with weakened immunity.
Without treatment and vaccination, diphtheria can lead to severe complications and even death.
2. Symptoms of diphtheria
Most common symptoms
The first symptoms usually resemble a "common infection":
sore throat, hoarseness, cough,
low-grade fever or fever,
malaise, weakness,
enlarged, painful lymph nodes in the neck.
After new days, a symptom typical of diphtheria may appear:
a thick, grey-white membrane (coating) on the tonsils and the back of the throat, which cannot be easily removed – attempting to scrape it off causes bleeding.
Depending on the location of the bacteria, we distinguish, among others:
pharyngeal diphtheria (diphtheria) – the most common form,
laryngeal diphtheria (croup) – with wheezing and a "barking" cough,
cutaneous diphtheria – difficult-to-heal ulcers at the site of bacterial entry.
How severe is the disease?
The course can range from moderate to very severe. In some patients, lesions are limited to the throat, in others, the toxin enters the bloodstream and damages many organs.
Possible complications
Diphtheria toxin can damage:
heart – myocarditis, arrhythmias, heart failure,
nervous system – weakness or paralysis of muscles (e.g., limbs, diaphragm),
respiratory muscles – which threatens respiratory failure,
respiratory tract – neck swelling and thick pseudomembranes can lead to suffocation.
Diphtheria mortality averages 5–10%, and in children <5 years and adults over 40 years of age, it can reach up to 20%.
trouble swallowing, "lump in the throat", very strong sore throat,
clear swelling of the neck,
high fever, significant weakness,
symptoms of muscle paralysis (drooping eyelids, weakness of limbs, difficulty walking).
If diphtheria is suspected, you must urgently see a doctor – the disease requires hospital treatment and administration of specific antitoxin and antibiotics.
3. Where does diphtheria occur?
Poland and Europe
Thanks to widespread vaccinations, diphtheria in Poland and most European countries is currently very rare – cases are sporadic, often related to lack of vaccination or an incomplete cycle.
However, with the decline in vaccination coverage, recurrences of the disease are observed, also in Europe.
World – areas of increased risk
Diphtheria is a cosmopolitan disease – it can occur on any continent, but the greatest risk concerns:
Africa, especially Sub-Saharan African countries,
South and Southeast Asia (including India, Bangladesh, Nepal, Indonesia, Philippines, Vietnam, Laos, Cambodia),
parts of the Middle East,
selected countries of Central and South America,
regions where the population vaccination level is low or there are interruptions in vaccination programs.
For whom is this information particularly important?
people traveling to African and Asian countries,
travelers going "off the beaten path" – backpacking trips, missions, volunteering, trips to families in rural areas,
medical workers, teachers, caregivers, and other people having close contact with a large number of people.
Before such a trip, it is worth checking the vaccination status and considering a booster dose.
4. How to protect yourself against diphtheria?
A. General prevention
Vaccination is the basis of protection, but additionally, it is worth:
avoiding close contact with people who have symptoms of respiratory tract infection,
using a mask and disposable gloves when caring for a sick person,
taking care of hand hygiene (washing hands with soap and water or alcohol-based preparations),
not touching the face (mouth, nose, eyes) with dirty hands,
using safe, proven accommodation and medical care while traveling.
For people who have had close contact with a diphtheria patient, a doctor may recommend prophylactic antibiotics and an additional dose of the vaccine.
B. Vaccination against diphtheria
Type of vaccine
The diphtheria vaccine contains diphtheria toxoid – a purified bacterial toxin devoid of virulence. It does not cause disease but teaches the immune system to recognize and neutralize the toxin.
In practice, combination vaccines are used, protecting simultaneously against:
diphtheria and tetanus (Td type preparations),
diphtheria, tetanus, and pertussis (Tdap),
diphtheria, tetanus, pertussis, and poliomyelitis (DTaP-IPV/Tdap-IPV).
Who should get vaccinated?
Children and adolescents
In Poland, vaccination against diphtheria is mandatory for children and adolescents up to 19 years of age.
Combination vaccines DTP/DTaP/Tdap are used in accordance with the Preventive Vaccination Program.
Adults
People vaccinated in childhood are recommended a booster dose every 10 years (most often in the form of a vaccine against diphtheria and tetanus, often with additional protection against pertussis).
People who have not been vaccinated or do not remember their status should consult a pharmacy vaccination point to establish primary vaccination (several doses).
Travelers
When traveling to countries where diphtheria still occurs, it is worth ensuring that the last booster dose was not later than 10 years ago.
If more time has passed – an additional booster dose is recommended before departure.
Vaccination schedule (adults)
1 booster dose every 10 years,
in previously unvaccinated persons – a series of primary doses, followed by booster doses.
Time of immunity development:
full immune response after a booster dose usually develops within approx. 2 weeks,
therefore, vaccination before travel is best performed at least 2–4 weeks before departure.
Booster doses and durability of immunity
After a full cycle of vaccinations in childhood, the effectiveness of protection reaches approx. 95–97%, but it is not lifelong,
the level of antibodies gradually decreases, therefore booster doses are recommended every 10 years, especially for travelers and those exposed professionally.
5. Summary
Diphtheria is a serious, potentially fatal disease that can be effectively controlled thanks to vaccinations.
Why is it worth getting vaccinated?
the vaccine protects against severe disease, nerve paralysis, heart damage, and the risk of suffocation,
reduces the risk of getting sick while traveling to countries where diphtheria still occurs,
limits the spread of the disease in society.
Who should especially consider vaccination/booster dose?
adults who have not been vaccinated in the last 10 years,
people with an incomplete or unknown vaccination schedule,
travelers going to countries in Africa, Asia, Central and South America,
people having frequent contact with children, sick people, or those with reduced immunity.
When is the best time to get vaccinated before typical travel?
optimally 2–4 weeks before departure, so that the body has time to build full protection.
If you are planning a trip or do not remember when you were last vaccinated against diphtheria, it is worth consulting a pharmacy vaccination point and supplementing protection. This is a simple step that can protect against a very dangerous disease.