What is the cause, management, and prevention of astrovirus infections?

From the Guidelines

Astrovirus infections are primarily caused by fecal-oral transmission of the virus, which commonly affects children under 5 years old, elderly individuals, and immunocompromised patients. The main cause of astrovirus infections is the transmission of the virus through contaminated food, water, and surfaces, with an incubation period of 24-36 hours, causing gastroenteritis symptoms including diarrhea, vomiting, abdominal pain, and sometimes fever and headache 1. Management focuses on preventing dehydration through oral rehydration solutions and maintaining electrolyte balance. Most infections resolve within 2-3 days without specific treatment, though immunocompromised patients may experience prolonged symptoms requiring more intensive supportive care.

Key Points to Consider

• The virus spreads through contaminated food, water, and surfaces, with an incubation period of 24-36 hours, causing gastroenteritis symptoms including diarrhea, vomiting, abdominal pain, and sometimes fever and headache 1.
• Children less than 7 years of age are principally affected, although adults can be infected and suffer mild disease 1.
• Prevention is key and includes thorough handwashing with soap and water for at least 20 seconds, especially after using the bathroom and before handling food; proper food handling and preparation; drinking clean water; disinfecting surfaces with chlorine-based cleaners; and isolating infected individuals, particularly in institutional settings like daycares, schools, and nursing homes.
• The characteristics of immunity to astrovirus are unknown, but young adults may have resistance to infection, and this immunity may wane with age 1.

Management and Prevention

• Prevention is key and includes thorough handwashing with soap and water for at least 20 seconds, especially after using the bathroom and before handling food.
• Proper food handling and preparation, drinking clean water, and disinfecting surfaces with chlorine-based cleaners can also help prevent the spread of the virus.
• Isolating infected individuals, particularly in institutional settings like daycares, schools, and nursing homes, can also help prevent the spread of the virus.
• Management focuses on preventing dehydration through oral rehydration solutions, such as Pedialyte or homemade solutions containing 6 teaspoons of sugar and 1/2 teaspoon of salt per liter of clean water, and maintaining electrolyte balance.

From the Research

Causes of Astrovirus Infection

• Astroviruses are nonenveloped, positive-sense single-stranded RNA viruses that cause gastrointestinal illness, particularly in children, the elderly, and immunocompromised populations 2.
• The virus can infect in a species-specific manner, but there is growing evidence that astroviruses have the potential to cross species barriers 2, 3.
• Astrovirus infection can be especially problematic in immunocompromised people and infants, where the virus has been associated with necrotizing enterocolitis and severe and persistent diarrhea, as well as rare instances of systemic and fatal disease 4.

Management of Astrovirus Infection

• The standard management of astrovirus infections is restoration of fluid and electrolyte balance and then maintenance of hydration until the infection resolves 5.
• WHO oral rehydration therapy (ORT) is commonly used to treat astrovirus infections, and hypotonic ORS appears to be safe and effective in all forms of acute diarrhea in childhood 5.
• Nitazoxanide (NTZ) has been shown to block astrovirus replication in vitro and in vivo, and may be an effective therapeutic strategy against astrovirus disease 4.

Prevention of Astrovirus Infection

• Understanding the immune response to astrovirus infection is crucial for the development of effective prevention and treatment strategies 6.
• Adaptive immunity is important in restricting classic and novel astrovirus infections, while the innate immune system plays a role in limiting astrovirus replication 6.
• Further research is needed to understand the factors that influence viral spread and the potential for cross-species transmission of astroviruses 3.