Meningitis is a major cause of mortality in southern Africa. We aimed to describe the aetiologies
and frequencies of laboratory-confirmed fungal and bacterial meningitis among
adults in a South African province with an 11% HIV prevalence, over 4 years.
We conducted a retrospective, observational study of secondary laboratory data, extracted
on all cerebrospinal fluid (CSF) specimens submitted to public-sector laboratories in Gauteng
province from 2009 through 2012. We calculated cause-specific incidence rates in the
general and HIV-infected populations and used Poisson regression to determine if trends
We identified 11,891 (10.7%) incident cases of meningitis from 110,885 CSF specimens.
Cryptococcal meningitis, tuberculous meningitis and pneumococcal meningitis accounted
for 62.3% (n = 7,406), 24.6% (n = 2,928) and 10.1% (n = 1,197) of cases over the four-year
period. The overall incidence (cases per 100,000 persons) of cryptococcal meningitis
declined by 23% from 24.4 in 2009 to 18.7 in 2012 (p <0.001) and decreased by 19%
among HIV-infected persons from 178.2 to 144.7 (p <0.001). Tuberculous meningitis
decreased by 40% from 11.3 in 2009 to 6.8 in 2012 (p <0.001) and decreased by 36%
among HIV-infected persons from 54.4 to 34.9 (p <0.001). Pneumococcal meningitis
decreased by 41% from 4.2 in 2009 to 2.5 in 2012 (p <0.001) and decreased by 38% among HIV-infected persons from 28.0 to 17.5 (p <0.001). Among cases of other bacterial
meningitis (248/11,891, 2.1%), Neisseria meningitidis (n = 93), Escherichia coli (n = 72)
and Haemophilus influenzae (n = 20) were the most common organisms identified.
In this high HIV-prevalence province, cryptococcal meningitis was the leading cause of laboratory-
confirmed meningitis among adults. Over a 4-year period, there was a significant
decrease in incidence of cryptococcal, tuberculous and pneumococcal meningitis. This
coincided with expansion of the national antiretroviral treatment programme, enhanced
tuberculosis control programme and routine childhood immunisation with pneumococcal
S1 Table. Possible nosocomial and uncommon bacterial and fungal causes of meningitis
isolated fromCSF culture specimens among adults in Gauteng Province, 2009–2012. Possible
nosocomial and uncommon organisms do not usually cause community-acquiredmeningitis
but may cause meningitis due to the consequences of neurosurgical procedures or
dissemination following bacteraemia.As clinical and other laboratory parameters were not
available, we were unable to determine if these organisms were significant in causing meningitis.