The advent of vaccines has saved numerous lives but some parents refuse to have their children immunized for a wide range of reasons ranging from religious beliefs to concerns over the risks of getting the shot.
The consequence of such decision has proved fatal for a 6-year old boy, from Olot in Spain, who died because of diphtheria, the first case of the disease in the country since 1987.
The boy, who had been in the pediatric intensive care unit of Vall d'Hebron university hospital since the end of May, died early on Saturday.
He was not vaccinated against diphtheria because his parents were against him getting inoculated amidst controversies over the shot's potential side effects.
The boy's treatment experienced delays because of difficulties in getting the right antitoxin in Europe. It was eventually provided by Russia.
The health services in Spain's Catalonia region said that one adult and nine other children were exposed to the bacteria but were lucky enough to have not developed the disease because they were all vaccinated.
Vaccination rates in Spain is high but health experts continue to urge parents to have their children vaccinated.
While there are concerns over the ill effects of vaccination, severe reactions are extremely rare.
"We are appealing to parents to have their children vaccinated," said Catalonia's health chief Boi Ruiz.
"The risk is not zero. But we cannot use the fact that the risk isn't zero to create fear amongst parents over the vaccine."
Diphteria is an infection that primarily affects the throat and the nose. It is caused by the bacterium Corynebacterium diphtheria. The condition can lead to a thick coating called a "pseudomembrane" to build up in the nose of throat which makes breathing and swallowing difficult.
The disease can lead to heart failure, paralysis, difficulty breathing and even death. Symptoms of the disease include fever, weakness, sore throat and swollen glands in the neck.
Diptheria is a contagious disease that can spread from person through coughing or sneezing. Infection can also be contracted when a person gets in contact with an object contaminated by diphtheria-causing bacteria.
Although the disease is very infectious, it has become increasingly rare in western Europe due to high vaccination rates.
Figures from the World Health Organization (WHO) show that as of 2013, 84 percent of infants globally were immunized against diphtheria, tetanus and whooping cough, infectious diseases that are potentially fatal.
Photo: ZaldyImg | Flickr