In recent study of Pfizer's Prevnar 7 vaccine, which is used for treatment of pneumonia and meningitis, it has been found that the vaccine is capable of blocking possibility of reappearance in HIV infected patients . The research appeared in the New England Journal of Medicine.

This study was conducted at the Malawi-Liverpool-Wellcome Trust Clinical Research Programme, University of Malawi College of Medicine in Blantyre, Malawi. It was concluded that three out of four or 74% of frequent cases of invasive pneumococcal disease (IPD) in patients infected with HIV were prevented by this vaccine.

Although being offered at a price of $40 per dose, which may not be affordable by people living in poor countries, the vaccine is believed to be helpful in many other high risk groups. This vaccine, developed by pharmaceutical company Wyeth, was tested by experts on 500 HIV-infected adults. These were the adults who had recovered after being infected with IPD and treated in Queen Elizabeth Central Hospital in Blantyre.

The lead author of the story, Dr Neil French, London school of Hygiene and Tropical Medicine said, "This is the first trial to use a conjugate pneumococcal vaccine in an adult group and find clinical benefits. The vaccine's efficacy at low CD4 counts is remarkable. This is an important finding to support the further development and use of conjugate vaccines for adults in general".