Vaccines Offer Preventative Solutions to High Childhood Pneumonia Rates

By Howard Lesser 21 September 2009

A recent World Health Organization (WHO) study of two strains of pneumonia is providing African governments with their first ever country-by-country figures on the leading global killer of children under the age of five.

The results, which appeared in the September 12 edition of The Lancet, track the rates of pneumococcal (streptococcus pneumonia) and Hib (haemophilus influenza type b) strains of the infection. They cite four countries – Nigeria, Ethiopia, the Democratic Republic of Congo, and Kenya – as having the highest rates of the pneumococcal infection in Africa.

The worldwide figures are expected to help health ministries in more than 72 African and Asian countries expand supplies of highly effective vaccines, reduce costs to about 15 cents per dose, and encourage the introduction of nationwide inoculation campaigns.

Associate Professor Kate O’Brien of Johns Hopkins University’s Bloomberg School of Public Health is the primary author of the study. She says the findings clearly show the benefits that prevention strategies hold for a growing number of countries that deploy the vaccines.

“The good news is that the two vaccines are highly effective, even among children who have immune systems that are compromised, like children who have HIV infection. And they’re very safe. So it’s really the time to make a commitment and really introduce these vaccines and use them widely,” she said.

With new financing mechanisms fostered by the Global Alliance for Vaccinations and Immunizations (GAVI) and the United Nations Children’s Fund (UNICEF), Dr. O’Brien says governments are coming to realize the efficacy of acting to keep pneumonia in check before it requires treatment.

“There are over 30 countries, predominantly in Asia and Africa, that have expressed interest that they would like to introduce the pneumococcal vaccine. 11 of them have received approval to actually do so, and two of them, Rwanda and the Gambia, have actually introduced pneumococcal vaccine in 2009. These two countries have really shown their leadership by proceeding with early introduction of vaccine and will be quickly followed by a number of other countries,” she noted.

Among the African countries hardest hit by childhood pneumonia, Dr. O’Brien says several have applied to GAVI and UNICEF and are close to embracing full-fledged national inoculation campaigns.

“The Democratic Republic of Congo is an approved country. There are other African countries, like Kenya, that has applied and has received approval for introduction of vaccines. There are a number of other countries that are very important -- Nigeria for instance -- that have applied, and decisions are being made about when they’ll be able to introduce,” she said.

Children play in the streets of Dithlake, a poor area in South Africa's Free State province.... Few of the children here have been vaccinated against early childhood diseases, like pneumonia and meningitis.

The WHO findings uncover several factors that are responsible for higher rates of infection. Dr. O’Brien says these include malnutrition, greater exposure to air pollution, smoke, and poor ventilation, remote or limited access to medical facilities, and a high rate of HIV infection, which she says weakens human immune systems and invites pneumonia. Despite this, the countries in southern Africa which are hit hardest by HIV/AIDS are not necessarily the countries with the highest rates of childhood pneumonia.

“In the estimates that we’ve provided of pneumococcal deaths, we did include the risk of HIV infection in those estimates. So we have already accounted for that. And if you dig a little deeper into the numbers, you certainly do see that children with HIV infections are about 40 times more likely to develop pneumococcal disease than a child who doesn’t have HIV infections,” Dr. O’Brien explains.

Other reasons she cites that account for the higher rates of pneumococcal disease among children in Nigeria, Ethiopia, Kenya and the DRC can be attributed to demographics and environmental factors.

“Some of the countries that we are talking about are countries for instance like Nigeria, which has a very large population. And therefore, there are lot of kids, among whom there are some proportion who will die. The other feature that leads to a high number of pneumonia or pneumococcal deaths among children is the actual mortality rate. That has to do with their access to care, their ability to encounter a medical system where you can actually get treatment, and it also has to do with underlying conditions of malnutrition or other poverty-associated conditions like vitamin deficiencies or air pollution issues,” she points out.

Some countries like Angola, which measured one of the highest rates of childhood Hib pneumonia nine years ago, have made great strides in the past four or five years to overcome these statistics by engaging in international health authorities’ recommendations and no longer face the daunting threats of growing infections portrayed by the 2000 WHO study.