Features of cholera and Vibrio parahaemolyticus diarrhoea endemicity in Calabar, Nigeria

Abstract

The clinical and epidemiological features of acute vibrio diarrhoeal disease were studied in 881 patients seen at the University of Calabar Teaching Hospital (UCTH), Calabar, Nigeria, between January and December 1989. Stools and rectal swabs of patients and randomly-selected control subjects were microscopically and culturally examined for the presence of enteric pathogens. Households of vibrio diarrhoea cases and matched controls were visited for ecologic studies. Of a total of 108 (12.3%) culturally-confirmed bacterial diarrhoeas, 47 (43.5%) were due to Escherichia coli, 33 (30.6%) to Vibrio cholerae-01 (classical and El Tor biotypes) and V. parahaemolyticus, while shigellae and salmonellae accounted for 29 (26.9%) and 9 (8.3%) cases, respectively. Most cholera case households clustered within the ancient neighbourhood of the inner city, characterized by poorly developed water and sewage disposal systems. A preponderance of vibrio diarrhoea patients were children < or = 10 years. Adult cases involved mostly females. The only case of diarrhoea-related death involved an eight-month old child with kwashiorkor and V. parahaemolyticus infection. Incidence of vibrio diarrhoeas was seasonal, with most cases occurring during the dry season followed by subsidence at the onset of rainy season. Bimodal peaks of vibrio diarrhoeal episodes observed over the period appeared to coincide with periods of acute water scarcity, high temperature, increased fishing activities and trade traffic on the Calabar River estuary. Of the environments sampled, only clam shells from a case household and river sediments yielded vibrio pathogens on culture. Ecological factors that are capable of stabilizing a focus of vibrio diarrhoea endemicity in this area are highlighted.

Vibrio species from diarrhoeal stools and water environment in Cross River State, Nigeria

“…The three species of Vibrio, namely, V. cholerae, V. parahaemolyticus and V. alginolyticus, isolated from the environment are known human pathogens and the first two have been associated with clinical conditions and environmental contamination in the region (Utsalo et al 1992, Eko et al 1994. The work reported here further provides the relative numbers of the Vibrio, even at different seasons.…”

Environmental Vibrio spp., isolated in Mozambique, contain a polymorphic group of integrative conjugative elements and class 1 integrons

“…The genus Vibrio includes many harmless species, natives of fresh, brackish and marine waters and is an important component of the aquatic microbial communities (Colwell & Huq, 1994), also able to persist in shellfish. Among these should also be mentioned some etiologic agents of enteric diseases and epidemics (Faruque et al , 1998; Sechi et al , 2000; Gil et al , 2004): O1 and O139 serotypes of Vibrio cholerae , some V. cholerae non‐O1 serotypes (Thungapathra et al , 2002), Vibrio parahaemolyticus (Utsalo et al , 1992), Vibrio fluvialis (Ahmed et al , 2004) and Vibrio alginolyticus (Ripabelli et al , 2003).…”

What are the drivers of recurrent cholera transmission in Nigeria? Evidence from a scoping review

“…Rainfall [7,26,30,32,45,62] and temperature [7,26,50] were identified as primary climatic drivers of cholera transmission in Nigeria. The association between cholera outbreaks and climatic drivers, particularly seasonal tropical rainfall, is well documented in other contexts [63][64][65][66].…”

“…Eight studies [12,17,24,32,41,50,70,75] found the potential role of health systems-related factors in driving the transmission of cholera in Nigeria. Regarding health service delivery, evidence centred on inadequate and inefficient surveillance system, as well as inadequate laboratory diagnostic capacity; in addition, poor technical capacity of health workers to manage cholera cases, especially in rural areas.…”