Quantitative RT-PCR detection of hepatitis A virus, rotaviruses and enteroviruses in the Buffalo River and source water dams in the Eastern Cape Province of South Africa

Abstract

Human enteric viruses (HEntVs) are a major cause of water-related diseases. The prevalence of hepatitis A virus (HAV), rotaviruses (RoV) and enteroviruses (EnV) in Buffalo River waters was assessed quantitatively over a period of 12 months (August 2010 to July 2011). Seventy-two samples were collected from six sites, including three dams, and concentrated using the adsorption-elution method. Viral RNA was extracted using a commercial kit, and the viruses were quantified by real-time quantitative reverse transcriptase PCR (RT-qPCR). Two or more viruses were detected in 12.5% of the samples. HAV was detected in 43.1% of the samples and in significantly (p < 0.05) varying concentrations of 1.5 × 10(1)–1.9 × 10(5) genome copies/L compared to RoV and EnV, while RoVs were detected in 13.9% of samples, with concentrations ranging from 2.5 × 10(1)–2.1 × 10(3) genome copies/L, and EnV were detected in 9.7% of the samples, with concentrations ranging from 1.3 × 10(1)–8.6 × 10(1) genome copies/L. Only HAV was detected at all the sites, with the Bridle Drift Dam recording significantly higher (p < 0.05) concentrations. The presence of enteric viruses in Buffalo River may constitute public health risks and the incidence of HAV at all the sites could reflect both the epidemiological status of hepatitis A and HAV persistence in the water environments.

Figure 1

The study area and samplingsites.

Figure 2

Spatial and monthly variations in concentrations of enteric RNA viruses (log₁₀ genome copies/litre) in water samples collected from six sites in the Buffalo River.

Figure 3

The detection rates for enteric viruses in the Buffalo River and at the six sampling sites along the Buffalo River.