Diphtheria is a serious bacterial infection, which the causative agent is Corynebacterium diphtheriae, that usually affects the mucous membranes of the nose and throat and sometimes skin.
In fact, the etymology of diphtheria is named for the tough pseudomembrane that forms in the patient’s throat.
The disease is passed from person to person by droplet transmission, usually by breathing in bacteria after an infected person has coughed, sneezed, or even laughed. It can also be spread by handling used tissues or by drinking from a glass used by an infected person. People can also get sick from touching infected sores on persons with the skin form of diphtheria. The diphtheria bacteria make a toxin that sickens people.
Fortunately, it is a vaccine-preventable disease.
In the US for example, 206,000 cases of diphtheria were recorded in 1921, resulting in 15,520 deaths. Before there was treatment (diphtheria antitoxin and antibiotics) for diphtheria, up to half of the people who got the disease died from it.
Since the introduction of diphtheria vaccines, which began in the 1920s and 1930s, and implementation of universal childhood vaccination in the late 1940s, diphtheria has been well-controlled in the United States. Diphtheria is now rarely reported in the US.
However, the disease continues to cause illness globally and there have been outbreaks reported in recent years.
I’ve been monitoring the large diphtheria outbreak in Nigeria since the beginning of the year and from May 2022 through July 2023, the country has reported 4,160 suspected cases, including 1,534 confirmed cases. Of the confirmed cases, 137 deaths (CFR: 8.9%) were reported.
The Nigeria Centre for Disease Control and Prevention (NCDC) reported in July—Despite the availability of a safe and cost-effective vaccine in the country, the majority 82% of confirmed diphtheria cases in this ongoing outbreak were unvaccinated.
The outbreak in Nigeria prompted a travel advisory from the Centers for Disease Control and Prevention (CDC).
Now we learn of another diphtheria outbreak in West Africa in the country of Guinea.
The World Health Organization (WHO) report on an outbreak that started on July 4 in Kankan region of Guinea.
From the beginning of the outbreak on 4 July to 27 August, a total of 117 suspected cases were reported, including seven confirmed cases. In total, 37 deaths have been reported, including all confirmed cases. Nine (24.3%) deaths occurred in the community. At present, 189 active contacts are under followed up.
Siguiri District in the Kankan region accounted for 85.5% of the total cases (100).
According to estimates in Guinea, routine immunization coverage for the third dose of pentavalent vaccine (which includes diphtheria vaccine) was 47% in Guinea in 2022, and even lower in the Kankan region according to a recent survey.
In addition, in North Africa, Algeria’s Ministry of Health announced emergency measures to contain a diphtheria outbreak in the southern regions on August 3. There have been 80 cases, including 16 confirmed cases reported.
Vaccination against diphtheria is essential to protect against disease. Diphtheria toxoid is one of the safest vaccines available. Individuals with an anti-diphtheria toxin antibody level of more than 0.1 IU/mL are considered fully protected from disease.