Diphtheria is a disease caused by bacteria that infect the upper respiratory tract and, in less cases, the skin. The disease's bacteria also secrete a toxin that destroys the heart and nerves.
Diphtheria is a disease that can be prevented by vaccines, but several regular and booster doses of anti-diphtheria vaccines must be given to generate and maintain the necessary immunity to it.
People who are not immunized or are immunocompromised are at risk of contracting the disease.
Diphtheria can kill unvaccinated individuals in about 30% of cases if they do not receive the necessary treatment, noting that young children are most at risk of dying from the disease (1) .
Recent diphtheria outbreaks highlight the importance of maintaining high rates of vaccination coverage in communities throughout the lifespan.
In 2022, it was estimated that 84% of children worldwide would have received the recommended three doses of diphtheria vaccine during infancy, leaving 16% of children with no or incomplete vaccine coverage. There is wide variation in coverage rates between and within countries.Overview
Diphtheria is an infectious disease caused by bacteria that secrete toxins. It can be transmitted from one person to another when an infected person coughs or sneezes. Some people may not show symptoms of the disease, but they can still transmit the bacteria to others. Others develop mild illness, although severe illness, complications, and even death are also possible.
Diphtheria can infect anyone but is most common among unvaccinated children.
The toxin from diphtheria causes damage to the respiratory system and can spread throughout the body. Common symptoms include fever, sore throat, and swollen glands in the neck.
Vaccination is the best way to prevent contracting diphtheria or transmitting it to other people, knowing that the vaccine against it is safe and helps the body fight the infection.
Cases of the disease were widespread throughout the world before the diphtheria vaccine was introduced and individuals were widely vaccinated with it in the 1930s.
Due to the recent lack of vaccination, outbreaks of the disease have occurred with increasing frequency despite the availability of a safe and effective vaccine against it.
Impacts of the COVID-19 pandemic
The COVID-19 pandemic has affected the delivery of routine immunization services and surveillance activities. These setbacks have left many children vulnerable to vaccine-preventable diseases such as diphtheria.
No WHO region is completely free of diphtheria, and the disease bacteria are able to circulate in some regions due to low rates of immunization coverage with the diphtheria toxoid vaccine, which increases the likelihood of outbreaks of the disease and exposes all unvaccinated and under-vaccinated individuals to the risk of contracting the disease.
Immunization and surveillance programs should be strengthened within primary health care, and efforts should be made to provide all children with 3 doses of diphtheria toxoid vaccine during infancy, childhood and adolescence. Countries should also implement robust surveillance systems to identify and confirm cases and quickly close immunity gaps.
Signs and symptoms
Diphtheria symptoms usually begin 2 to 5 days after exposure to the bacteria that causes it. Typical symptoms of an infection include sore throat, fever, swollen glands in the neck, and weakness. Within two to three days following infection, dead tissue in the respiratory system forms a thick, gray layer that can cover the tissues in the nose, tonsils, and throat, making breathing and swallowing difficult.
Most cases of severe diphtheria and deaths resulting from it occur due to the toxins it secretes and the effects it leaves behind. Complications resulting from the disease can include inflammation of the heart and nerves. The disease can kill individuals who are not vaccinated against diphtheria and do not receive appropriate treatment for it in about 30% of cases, noting that children under the age of five are most at risk of death from the disease.
Who is at risk of the disease?
The disease can infect anyone who is not vaccinated (unvaccinated or undervaccinated).
There have been cases of diphtheria reappearing at times of low immunization coverage rates. Routine immunization efforts are hampered by damaged health infrastructure and health services in countries experiencing or recovering from natural disasters or conflicts. The risk of infection with the disease also increases in densely populated residential camps.
treatment
The risk of complications from the disease or death due to it is greatly reduced if the necessary treatment is provided early in the infection stage. For this reason, if diphtheria is suspected, an immediate examination should be performed to confirm the disease and treatment should be started as soon as possible.
Diphtheria cases are usually treated with antitoxins and antibiotics, as diphtheria antitoxins specifically work to neutralize the circulation of toxins in the blood. Detailed instructions on administering antivenom can be found by referring to WHO guidelines on treatment. Antibiotics work to stop the reproduction of bacteria and stop the secretion of toxins, thus accelerating the process of getting rid of bacteria and preventing their transmission to others. However, many currently circulating diphtheria strains have shown resistance to some commonly used antimicrobial drugs. The vaccine should also be given to all individuals who have previously had diphtheria after the acute phase of the disease has passed.
Individuals who have been in contact with diphtheria cases should also be treated with antibiotics as a preventive measure to prevent them from contracting the disease. The immunization status of all contacts must also be verified, and they should be provided with the vaccine if they are not fully vaccinated.
protection
Diphtheria can be prevented with vaccines often given in combination with tetanus, pertussis, and other diseases. The organization recommends giving a total of 6 doses of the diphtheria vaccine from 6 weeks of age until adolescence to provide long-term protection.
Perhaps the most effective way to prevent diphtheria is community-based vaccination combined with high coverage rates within the delivery of routine immunization services included in primary health care. All children should be vaccinated against diphtheria with the full initial series of vaccine and 3 additional booster doses to provide long-term protection, knowing that the vaccine is safe and effective.
The diphtheria vaccine is often given in combination with vaccines against other diseases such as tetanus, pertussis, Haemophilus influenzae, hepatitis B, and inactivated polio.
Combining vaccines increases the cost slightly but allows the costs of implementing and administering the vaccine to be shared; Most importantly, it adds the benefit of protection against other childhood diseases that can cause tetanus, whooping cough, meningitis and polio.
In 2022, 84% of children received all three doses of the initial series of diphtheria vaccine, although there are large variations in coverage rates between and within countries.
Lack of vaccination in successive groups of children can lead to cases and outbreaks of diphtheria.
