The Respiratory and Meningeal Pathogens Research Unit (RMPRU) is mandated to study the causes of respiratory and meningeal infections. Both clinical and basic research is conducted with the aim of improving

the diagnosis, management and prevention of these diseases.



Pneumococcal disease and vaccines


Pneumococcal disease is a major killer of children globally, surpassing the combined mortality associated with HIV, TB and malaria. The unit has been in the forefront of vaccine strategies to prevent pneumococcal disease. The safety and immunogenicity of a novel 10-valent pneumococcal conjugate vaccine (PCV) was evaluated in HIV-infected and HIV-uninfected children. This study also examined the immunogenicity of different PCV dosing schedules, to help determine the optimal schedules for countries such as South Africa. Additional immunogenicity studies were undertaken on a 7-valent PCV vaccine in HIV-infected and HIV-uninfected children to address issues such as immune responses following reduced doses of PCV, as well as the effect of PCV on pneumococcal colonization in HIV-infected and HIV-uninfected children. The Unit has also undertaken case-control studies to determine the effectiveness of PCV in the prevention of pneumonia and invasive pneumococcal disease since its introduction into the South African Immunization program. The unit is exploring through biennial community wide surveys, the indirect effect which childhood PCV immunization will have on unvaccinated children and adults in rural and urban South Africa.

Some sero-epidemiological studies have been undertaken to identify the potential of common protein antigens as future vaccine-candidates.



Influenza virus disease and vaccines


The Unit undertook in collaboration with other HIV Units, the first efficacy and immunogenicity studies on the efficacy of the influenza vaccine in HIV-infected adults and the only efficacy trail to-date in HIV-infected children. Key findings from these studies included demonstrating that whereas the influenza vaccine was efficacious in HIV+ adults, preventing 75% of influenza-confirmed illness; the vaccine was not efficacious in young HIV-infected children. These studies underscored the need to review policy on the use of influenza vaccines in HIV-infected individuals. The unit has embarked on a $10 million project, funded by the Bill and Melinda Gates Foundation, which is examining the safety and efficacy of influenza vaccination in pregnant HIV-infected and HIV-uninfected women in protecting their young infants from influenza illness, as well as maternal-immunization possibly reducing the risk of premature births and still-births.



Rotavirus vaccine


Rotavirus is the most important cause of diarrheal death during childhood globally. The Unit participated in the pivotal African study which evaluated the efficacy of Rotarix® in Africa. In addition, the Unit has more recently reported on the sustainability of protection of Rotarix beyond infancy, and compared efficacy and immunogenicity of two to three doses of Rotarix.  Also, aimed at improving the immunogenicity of the vaccine, the Unit has investigated the effect which breast-feeding might have on the immunogenicity of the vaccine. The Unit is also spearheading a multi-centered study in South Africa, which is evaluating the effectiveness of Rotarix in preventing diarrheal hospitalization since its introduction into the routine childhood immunization program.  



Group B streptococcus (GBS)


The Unit has undertaken a number of epidemiological and immunological studies relate to GBS, a leading cause of death during the neonatal period, in the past two-years. These studies aim at identifying correlates of protection against GBS colonization in pregnant women, as well as against developing invasive disease in newborns and young infants. In addition, the Unit has been in the forefront of the evaluation of a new trivalent GBS polysaccharide protein conjugate vaccine in pregnant HIV-infected and HIV-uninfected women.



Other vaccine studies:


The Unit was the largest recruiter in a multi-centered study which evaluated the safety and immunogenicity of a chimeric RSV-PIVIII combination vaccine in children. Also, studies on the safety and immunogenicity of a new liquid formulation of hexa-valent vaccine, which includes epitopes of diphtheria, tetanus, hepatitis B, polio,  Haemophilus influenza type b and pertussis were completed. This vaccine will help reduce the number of injectables given to children, as well as improve compliance and the timeliness of vaccination.



Other clinical studies:


The Unit is one of seven centers globally which is participating in a pneumonia etiology study in children that is funded by the Bill and Melinda Gates Foundation. This study, which uses novel molecular diagnostic tests to identify pathogens which may cause pneumonia, is expected to be  landmark study in relation to the future use of molecular diagnostic tests in attributing causality to pathogens. Also, the results of this study are expected to guide future empiric treatment of childhood pneumonia in settings where pneumococcal and H. influenza type b conjugate vaccines have been introduced.




Research Highlights

VPD/RMPRU

11th Floor Central West Wing

Nurses Residence

Chris Hani Baragwanath Hospital

Diepkloof, Soweto

Phone: 011 983 4283

Fax: 086 646 4208

E-mail: siwei@rmpru.co.za