The burden of shigellosis and antibiotics resistance trends in Richmond area of Johannesburg, South Africa

Abstract

Diarrhoea, particularly infectious diarrhoea, in children below five years of age is recognised as one of the leading cause of morbidity and mortality throughout the world. This is especially true in residential areas of developing countries where there is substandard sanitation and overcrowding which are reservoirs for farther transmission. Shigellosis is endemic in developing countries and in Sub-Saharan Africa, including South Africa, a region where unique geographic, economic, political, sociocultural, and personal factors interact to create distinctive continuing challenges to prevention and control. Our study was undertaken to establish baseline information on incidences of Shigella, its serotype and resistant pattern of isolates from human faeces from residents of Johannesburg, South Africa. All stools received from January to April 2013 from the private health care system were cultured on standard media for isolation of Shigella and confirmed by standard biochemical reactions and serological method. Antibiotic sensitivity test was determined by the agar diffusion method. 11009 stool samples were assayed from patients aged between 22 days to 94 years with a 110 Shigella isolates yield, of which 47 (43%) were S. flexneri, 61 (55%) S. sonnei and 1 (1%) of S. dysentriae and S. boydii respectively. Majority of patients 76 (69%) were children between < 1 to 5 years old followed by those between 6 to 10 years 13(12%). Of the four species isolated from children of up to 10 years old, S. sonnie was confirmed in 52 cases (59%) and S. flexneri in 36 cases (41%). A total of 53 (48%) males and 57 (52%) females were infected. However, a hundred per cent susceptibility to ciprofloxacin and ceftriaxone but high levels of resistance to Co-trimoxazole (83%), tetracycline (72%), and ampicillin (26%) was noted. From the 110 isolates, 96 (87%) were resistant to one or more drugs while 14 (13%) were fully susceptible. These results show that S. sonnei followed by S. flexneri as predominating aetiology of shigellosis and Ceftriaxone and ciprofloxacin as effective drugs against all four Shigella species.