Epidemiology of invasive pneumococcal disease in Kumasi, Ghana

Abstract

There are few data on the epidemiology of invasive pneumococcal disease in Africa. We undertook a prospective study of these infections in Kumasi, Ghana, collecting clinical data on all patients with laboratory-confirmed pneumococcal meningitis, pneumonia or systemic sepsis associated with bacteraemia. A total of 140 cases were identified in the period from January 2002 to April 2005. The disease was most prevalent among patients <5 years of age and immediately following the peak of the harmattan wind. The majority of patients were treated with a combination of antibiotics, in part reflecting concerns regarding antibiotic resistance. Mortality was high (47%), with no evidence of an improved prognosis compared with earlier studies in the region. Although most isolates of pneumococci were resistant to tetracyclines and co-trimoxazole, there was no high-level resistance to penicillin and only 12% of isolates showed intermediate level resistance. Serotype 1 was the most common serotype (36%), whilst intermediate-level penicillin resistance was associated with serotype 14. Theoretical coverage by existing 7-, 9-, 11- and 23-valent vaccines was 26%, 63%, 64% and 76%, respectively. Vaccination may improve control of pneumococcal disease in Ghana, although modified vaccine formulations are required for local use.

Penicillin resistance and serotype distribution of Streptococcus pneumoniaein Ghanaian children less than six years of age

“…In an earlier carriage study from the Ashanti region of Ghana, 49% of children were found to carry S. pneumoniae and 39% of isolates showed intermediate penicillin resistance [17]. Holliman et al [27] described the history of S. pneumoniae penicillin resistance in Ghana and found that overall around 12% of isolates tested were intermediate resistant with the exception of a study in 1996 that reported 31% of isolates to be resistant [28]. However, this high rate of resistance was suspected to be due to the methodology used in the specific study [27,28].…”

“…Holliman et al [27] described the history of S. pneumoniae penicillin resistance in Ghana and found that overall around 12% of isolates tested were intermediate resistant with the exception of a study in 1996 that reported 31% of isolates to be resistant [28]. However, this high rate of resistance was suspected to be due to the methodology used in the specific study [27,28]. In a recent study conducted in the Ashanti region from 2008 to 2010, 99% of 91 invasive S. pneumoniae isolates were penicillin sensitive [29].…”

Pneumococcal infections and sickle cell disease in Africa: does absence of evidence imply evidence of absence?

“…These methods were not optimised for the detection and isolation of fastidious organisms such as the pneumococcus nor did the studies attempt to circumvent the confounding effect of prior antibiotic use in patients presenting to the hospital. While more recent studies which are population-based have used optimised laboratory techniques for isolation of the pneumococcus and culture media with an antibiotic removing device, these studies did not evaluate the role of SCD in children with invasive bacterial disease 33 34 35 36 37 38 39 40 41. Thus, while there have been several studies on the aetiology of invasive bacterial disease in children, none have specifically targeted the population of SCD subjects with an optimal study design and laboratory methods for isolating the pathogens that are most likely contributory to morbidity and mortality.…”

Maternal-child health

“…Since carriage always precedes invasive infections with respect to pneumococci, it is imperative to look for appropriate vaccines to reduce carriage rates of serotypes that are globally known to be multiple antibiotic resistant with a view to reducing morbidity and mortality rates among the vulnerable age groups in Ghana. Holliman et al (2007) investigated the epidemiology of invasive pneumococcal disease in Kumasi, Ghana. They observed that a very low resistance level to penicillin existed and that the theoretical vaccine coverage of the 7-, 9-, 11-and 23-valent vaccines was 26%, 63%, 64% and 76%, respectively.…”