How dangerous is diphtheria and is it contagious?

According to Associate Professor, Dr. Tran Dac Phu, former Director of the Department of Preventive Medicine, Ministry of Health, diphtheria is a dangerous infectious disease, although it belongs to group B. The disease is transmitted through the respiratory tract in the form of droplets. The disease can be transmitted directly through contact with a sick person when speaking, coughing, sneezing or indirectly through contact with secretions containing bacteria from the nasal mucosa of the patient or a healthy person carrying the infection.

The disease can also be transmitted indirectly through contact with objects contaminated with secretions of people infected with diphtheria bacteria such as clothes and hands that we do not clean well. The source of infection can be sick people or healthy people carrying the bacteria, so sometimes we do not know where we are infected.

Diphtheria used to be very common in both urban and rural areas, but thanks to the Expanded Immunization Program, the number of cases has now decreased significantly. After many years without a case, the disease has recently returned due to some problems related to vaccination.

Symptoms and prevention of diphtheria

There are many factors leading to low vaccination rates in some areas, such as the impact of the COVID-19 pandemic, which has led to many cases of not being vaccinated or not getting enough doses. Recently, there has been a shortage of vaccines in the Expanded Immunization Program, so remote areas have not been vaccinated. Meanwhile, in cities or the plains, many mothers take their children to get vaccinated through service injections (5-in-1 or 6-in-1 vaccines).

“That’s why the epidemic did not break out in the city or the plains. There was also a time when the epidemic broke out in the Central Highlands provinces, but now this area is free of the epidemic thanks to the campaign to supplement the tetanus-diphtheria vaccine with reduced doses for the people,”Associate Professor Phu said.

Preventive medicine experts note that people should not be subjective. When an epidemic breaks out, anywhere, in the city or in the countryside, in the mountains, anyone who does not have immunity (due to vaccination or infection) is likely to contract the disease with symptoms, or be infected with the bacteria and become a healthy carrier, and then spread the bacteria to others.

Those who have been in contact with the recent case should not be too worried. They have been given prophylactic antibiotics to kill the diphtheria bacteria immediately, not to develop the disease if they are unfortunately infected with the bacteria and not to become a source of infection for others.

According to Associate Professor, Dr. Tran Dac Phu, the development of the epidemic depends on the vaccination rate and the epidemic prevention and vaccination work of localities. If the epidemic is not well controlled, there will continue to be sporadic cases, and anyone who is not immune can get sick. The epidemic especially occurs in places with low vaccination rates, remote areas (vaccination "lowlands").

In the long term, the most effective way to prevent disease is vaccination. Children need to be vaccinated on schedule, with enough basic doses, then get booster shots according to the Ministry of Health's vaccination schedule. Adults need booster shots about every 10 years. In high-risk areas, the Ministry of Health can carry out sweep and supplementary vaccination campaigns.