Although the vast majority of infants in Singapore are given jabs against a range of infectious diseases, the number who get infected is still high.
Last year, Singapore had 148 cases of measles, 501 cases of mumps, 110 cases of rubella, or German measles, and 29 cases of pertussis, or whooping cough.
Singapore's immunization rates are comparable to those in Scotland, whose infection rate was used in a debate on whether Britain should make it compulsory for all infants to get two vaccines to protect them against six diseases.
Immunizations against measles and diphtheria are compulsory in Singapore, while those for the rest are voluntary.
A study by three doctors from the University College London and the University of Edinburgh compared Scotland's rate with the low rate of infection in Hungary, where immunization is compulsory.
They concluded that compulsory immunization made a big difference in the number of children falling sick.
In Scotland, voluntary immunization of children ranges from 89 percent to 98 percent, figures that are near those of Singapore.
The doctors wrote in a letter in the British Medical Journal this month: “The numbers of reported pertussis (98 versus 48), mumps (2,741 versus 16), rubella (146 versus 0) and measles (168 versus 0) cases were significantly higher in Scotland than in Hungary.”
Furthermore, Hungary's population is twice the size of Scotland's.
“We therefore believe that mandatory vaccination has considerable advantages over the voluntary system,” they concluded.
When asked about this, the Ministry of Health pointed to Singapore's comprehensive national childhood immunization programmed and said it “is regularly reviewed to ensure its relevance to our local disease situation”.
Despite immunization against measles and diphtheria being compulsory, not every child is shielded from the diseases.
Latest official figures show 95 percent of two-year-olds had protection against measles, and 90 percent against diphtheria, in 2010. Protection against diphtheria goes up to 95 percent when the children are in Primary 5 and the last booster shot is given.
Pointing to these “consistently high” levels of coverage, a ministry spokesman said: “This ensures there is sufficient herd immunity in our population to prevent outbreaks of these diseases.”
Last year, there were no cases of diphtheria, a bacterial infection that could cause inflammation of the heart muscle and damage the kidneys.
Whooping cough can kill young children, and the jab against it includes protection against diphtheria and tetanus as well. Infants get it at three, four and five months of age, with two booster shots given when they are older.
Immunization against measles, mumps and rubella is given as a single dose at age one, and a booster is given when the child is in Primary 1. (mtq)