Epidemiology of invasive pneumococcal disease in Saudi Arabian children younger than 5 years of age

This study evaluated the incidence, serotype distribution, and antimicrobial susceptibility of invasive pneumococcal disease [IPD] in Saudi Arabian children. This multicenter, prospective, clinical surveillance study included children under 5 years of age, residents of one of the seven study health areas, who were brought to a study hospital with suspicion of IPD. Bacterial isolates from sterile site samples, collected less than 24 h after hospital visit/admission, were identified, serotyped, and tested for antibiotic susceptibility. Between June 2007 and January 2009, 631 episodes of suspected IPD were recorded, and 623 were included in the analysis. One child [0.2%] had previously received one dose of a pneumococcal vaccine. Forty-seven episodes were positive for Streptococcus pneumoniae and three for Haemophilus influenzae. The incidence of confirmed IPD cases was estimated to be 2.5-21.6 per 100,000 children [<5 years]. Among the 46 S. pneumoniae isolates serotyped and tested for antibiotic susceptibility, the most common serotypes were 5 and 23F [20% each], 6B [17%], and 1 and 14 [11% each]. Sixty-three percent of isolates were multidrug-resistant. Vaccination of Saudi Arabian children with expanded-coverage conjugate pneumococcal vaccines containing serotypes 1 and 5 could have a substantial impact to prevent IPD in this population

prospective, observational, epidemiological evaluation of the aetiology and antimicrobial susceptibility of acute otitis media in Saudi children younger than 5 years of age

Information regarding acute otitis media [AOM] aetiology is important for developing effective vaccines. Here, bacterial aetiology and antimicrobial susceptibility of AOM were determined in young Saudi children. Children aged 3-60 months with a new episode of AOM, who had not received antibiotics or had received antibiotics for 48-72 h but remained symptomatic, were enrolled in this prospective, observational, epidemiological study in Riyadh. Middle ear fluid [MEF] samples were collected by tympanocentesis or from spontaneous otorrhea, and tested for the presence of Streptococcus pneumoniae, Haemophilus influenzae, Streptococcus pyogenes and Moraxella catarrhalis. Antimicrobial susceptibility of the identified pathogens was assessed using E-tests. Between June 2009 and May 2011, 66 children were enrolled. S. pneumonia was detected in 6 episodes and non-typeable H. influenza [NTHi] in 8 episodes. Moreover, Staphylococcus aureus, which is an uncommon cause of AOM, was detected in 17 episodes. Pneumococcal serotypes were 7F [n = 2], 23F [n = 2], 19F [n = 1] and 15F [n = 1]. Susceptibility to cefotaxime was observed in all pneumococcal and H. influenza isolates, to cefuroxime in 4/6 pneumococcal and 8/8 H. influenza isolates, and to penicillin in 5/6 pneumococcal isolates. S. pneumonia and NTHi were major bacterial contributors for AOM in Saudi children

Invasive meningococcal disease and travel

The epidemiology of invasive meningococcal disease varies geographically and in time and the risk of acquiring the disease varies regionally, as well as with living conditions and behavior. An area, in which meningococcal disease out-breaks have frequently occurred, is the "African meningitis belt", where epidemics of meningococcal disease with a peak incidence as high as 100-800/ 100,000 population/year have been reported. Another risk factor is mass gatherings including the Islamic pilgrimage to Makkah [Mecca], where outbreaks of meningococcal disease have repeatedly occurred. The latest outbreaks occurred during the Hajj pilgrimages of 2000 and 2001, when a shift from serogroup A disease to serogroup W135 occurred. Vaccination against serogroups A, C, W-135 and Y with novel conjugate vaccines may help protect individuals and reduce the spread of bacterial carriage and disease. Individuals who should be vaccinated include travelers to epidemic or hyperendemic areas [as identified by international health authorities], traverlers for Umra or Hajj [Hajj pilgrims], travelers to high risk countries or regions [African meningitis belt] during the dry season or countries in sub-Saharan Africa outside the meningitis belt [where outbreak of meningitis has been reported in the preceding 2-3 years], military recruits or deployed military personnel, immunocompromzed travelers and high school and college students. This review presents the global epidemiology of meningococcal disease, and discusses prophylaxis options including meningococcal ACWY vaccines

Molecular characterization of methicillin-resistant Staphylococcus aureus recovered from outpatient clinics in Riyadh, Saudi Arabia

To examine the recovered strains phenotypically, by conventional methods and genotypically by polymerase chain reaction [PCR], for direct detection of Staphylococcus aureus [S. aureus] 16S ribosomal Ribonucleic Acid [rRNA] gene [which serves as an internal control] and mecA gene. Secondly, introduce multiplex PCR targeting at the same time S. aureus 16S rRNA, Panton-Valentine Leucocidin [PVL], and staphylococcal cassette chromosome mec [SCCmec] type IV. Thirty-seven strains of S. aureus collected in 2007 from outpatient clinics in King Khalid University Hospital, Riyadh, Kingdom of Saudi Arabia, were tested in the College of Pharmacy phenotypically by conventional methods and genotypically by PCR for direct detection of S. aureus 16S rRNA and mecA genes. All the 37 strains, were tested also by multiplex PCR targeting at the same time S. aureus 16S rRNA, PVL, and [SCCmec] type IV. Polymerase chain reaction detected all the 37 bacteriologically positive S. aureus [100%] and the mecA gene in all strains phenotypically resistant to methicillin [100%], at the same time it detected the mecA gene in 2 strains phenotypically sensitive to methicillin. Only 3 strains [8.1%] recovered from skin and soft tissue infections were positive for PVL and SCCmec type IV. The PCR assay can be used for rapid detection of S. aureus and mecA gene. At the same time the multiplex PCR assay explained in this study is a rapid, sensitive, and reliable test for direct detection of community-acquired methicillin-resistant S. aureus

Trends in microbial resistance to antibiotics

During the past decade there had been major changes in the susceptibility of bacteria that caused various infections. Resistance to antiinfective agents, including antibiotics, is worldwide, both in developed and developing countries. The three fundamental mechanisms or microbial resistance are: 1] Enzymatic degradation of the drugs, 2] Alteration of antimicrobial targets and 3] Change in membrane permeability toantiboitics. Resistance can be either plasmid mediated or maintained on the bacterial chromosome. Almost all bacterial species can develop resistance to antiinfective agents and resistance can readily be transferred among bacteria by transmissible elements [plasmids]. The various mechanisms by which bacteria are able to overcome antibiotics are discussed in detail. Knowledge of resistance patterns and of the ways by which resistance is overcome are vital to the future of antimicrobial chemotherapy