Norovirus (Norwalk agent) : Norovirus is the most common cause of infectious gastroenteritis in the UK and causes outbreaks in closed communities, such as long-stay hospital wards, cruise ships and military camps. Food handlers may also transmit this virus, which is relatively resistant to decontamination procedures. The incubation period is 24–48 hours.
High attack rates and prominent vomiting are characteristic. Diagnosis is by electron microscopy, antigen or DNA detection (PCR) in stool samples. The virus is highly infectious and cases should be isolated and environmental surfaces cleaned with detergents and disinfected with bleach.
ASTROVIRUS
Astroviruses cause diarrhoea in small children and occasionally in immunocompromised adults.
Rotavirus: Rotaviruses are the major cause of diarrhoeal illness in young children worldwide and cause 10–20% of deaths due to gastroenteritis in developing countries. There are winter epidemics in developed countries, particularly in nurseries. Adults are less often infected but those in close contact with cases may develop disease. The virus infects enterocytes, causing decreased surface absorption. The incubation period is 48 hours and patients present with watery diarrhoea, vomiting, fever and abdominal pain. Dehydration is prominent. Diagnosis is aided by commercially available enzyme immunoassay kits, which require fresh or refrigerated stool sample.
The medicines that can be thought of use are:-