Pneumococcal Disease Research Unit

Research highlights

The outcome of a 5-year vaccine trial conducted in Soweto with 39 000 children showed that the 9-valent pneumococcal conjugate vaccine reduced the burden of invasive disease due to vaccine serotypes by 85% and was also shown to be efficacious in HIV-infected children. The 7-valent pneumococcal conjugate vaccine was licensed for use in South Africa in October 2005 and is currently available in the private sector. There are currently plans underway to introduce the vaccine into the Expanded Program for Immunization (EPI) within the next 12-18 months (2009).

National laboratory-based surveillance has shown that the introduction of the Haemophilus influenzae type b (Hib) vaccine has been successful in reducing the burden of disease in South Africa. Ongoing surveillance of Hib has shown that residual disease occurs in children with HIV-infection and these strains are more likely to be drug resistant.

The Unit has documented the first case of fluoroquinolone resistance resistance in a pneumococcus in Africa, including the first global case of fluoroquinolone resistance in a pneumococcus from a child. A subsequent carriage study highlighted the association between children in TB hospitals and carriage of fluoroquinolone-resistant pneumococci.

The Unit has contributed to the scientific knowledge base by determining novel mechanisms of resistance to β-lactams, oxazoladinones, chloramphenicol and macrolide antibiotics in the pneumococcus.

We have implemented several molecular diagnostic (PCR) assays to assist in the identification and serogrouping of our organisms including culture-negative blood and CSF specimens.

The Unit has documented the huge burden of disease due to Pneumocystis jirovecii infections in HIV-infected children and has completed the first study in Africa of the burden of human metapneumovirus infection in children.

Prof’s Klugman and Madhi contributed to the WHO guidelines for the treatment of pneumonia in HIV-infected children.

We have documented the replacement of heterogeneous serogroup A meningococcus with highly clonal serogroup W135 in Gauteng province and an increase in the total number of cases from this province.

Since 2004, annual GERMS-SA meetings have been held to re-evaluate and improve the surveillance network. Participants include representatives from the Centers for Disease Control and Prevention, Atlanta, GA, USA), Department of Health, clinicians, pathologists and technologists from all provinces.

Widespread use of cotrimoxazole for prophylaxis of opportunistic infections in HIV-infected individuals has major implications for the development of resistance in other bacteria. We have expanded our surveillance to monitor the impact of this resistance in all provinces. Ongoing analyses show dramatic increases in cotrimoxazole resistance in the pneumococcus.

The Unit reports weekly data for Streptococcus pneumoniae, Haemophilus influenzae and Neisseria meningitidis to the National Outbreak Response Team (NORT) and the National Department of Health.

Ongoing surveillance data informs pharmaceutical companies, vaccine manufacturers, public health specialists and clinicians nationally and internationally.