(September 11, 2009 - Insidermedicine)

Infections by two organisms, known as Streptococcus pneumoniae and Haemophilus influenzae, or Hib, cause a tremendous amount of serious illness in young children worldwide despite the availability of vaccines that can prevent these illnesses, according to two studies published in the latest issue of The Lancet.

Here is some information on vaccination from the World Health Organization (WHO):

•    Vaccination is extremely effective at reducing rates of infectious illness

•    Typically, vaccines are safer than medicines used to treat diseases

•    Worldwide, misguided concern about vaccine safety has led to the re-emergence of some serious diseases in some regions, including measles and whooping cough

In the first study, researchers from Johns Hopkins University in Baltimore used available worldwide disease data to estimate the overall global burden of disease caused by Streptococcus pneumoniae among children under the age of 5. In 2000, the year before the vaccine against Streptococcus pneumoniae was introduced, about 14.5 million children developed serious illnesses caused by this organism and over 800,000 died. Approximately11% of deaths occurred in children who were HIV-positive, and most of the deaths that occurred in children who were HIV-negative took place in Africa and Asia.

The next group of researchers, this time out of WHO in Geneva, estimated the worldwide burden of disease caused by Hib among children under the age of 5. They found that, in the year 2000, Hib caused 8.13 million serious illnesses in young children and nearly 400,000 deaths. Of these deaths, about 2% occurred in children who were HIV-positive.

Today's research demonstrates how a more comprehensive vaccination program against Streptococcus pneumoniae and Hib could dramatically reduce death rates in children under 5.