Essential facts about rotavirus

1. Rotavirus is the commonest cause of severe dehydrating diarrhoea among children worldwide.
2. Every child will suffer at least one infection by the time s/he is 3 years old.
3. Every year it causes:
   • 111 million cases of disease requiring home care only
   • 25 million clinic visits
   • 2 million hospitalizations
4. Annually there are more than 500 000 deaths in children aged five years or younger.
5. 85% of rotavirus deaths occurs in Africa and SE Asia (please see map below).  
6. Rotavirus vaccines have been proven to be safe and effective in children in both developing and developed countries.
7. Severe rotavirus disease is VACCINE PREVENTABLE.
8. Every child has a right to rotavirus vaccination.
9. Prevention of dehydration by providing timeous ‘Oral rehydration solution’ saves lives.
10. Antibiotics cannot cure rotavirus infection.

What is Rotavirus?

Rotavirus is a virus causing diarrhoeal disease in young children. It is the commonest and most important cause of severe diarrhoeal disease requiring hospitalization and resulting in mortality in infants and children. It accounts for approximately 42% of the cases of diarrhea.

In Africa, diarrhoeal disease is the 4th leading cause of death in children under the age of 5 years. It causes 701 000 deaths per year. Rotavirus disease is estimated to be responsible for 210 300 of these deaths per year or 576 deaths per day.

The virus

A rotavirus has a characteristic wheel-like appearance when viewed by electron microscopy (EM). The name rotavirus is derived from the Latin rota, meaning "wheel"(see Figure 1). Rotaviruses are non-enveloped, triple layered capsid RNA viruses. The genome is composed of 11 segments of double-stranded RNA, which code for six structural and five non-structural proteins. Rotaviruses are classified into groups A-E.  Group A rotaviruses cause most human infections, although Group B and C (associated with outbreaks) has also been found to infect humans. Group B rotaviruses are common animal pathogens infecting pigs, cows, sheep and rats, and Group C rotaviruses, commonly found in animals including pigs and dogs. The virus is stable in the environment.

Figure 1: Immune EM view of the rotavirus particle

 (Source. Parashar U, Bresee JS, Gentsch JR, and Glass RI. Rotavirus. Emerging Infectious Diseases. 1998;4(4):561)

How is Rotavirus spread?

Rotavirus is most commonly transmitted by the faeco-oral route by person to person contact through close contact. Other less common modes of transmission are contaminated food and water and possible airborne spread. There have been outbreaks in day-care centers, families and nursing homes. The have been hospital acquired infections in newborn nurseries and in children where there have been community outbreaks.

Rotavirus is highly infectious. The rotavirus is a small virus particle and is able to resist destruction by hand washing with disinfectant ~ and antibiotic soaps. There are large numbers and high concentrations of rotavirus in stools (1011 per ml of stool) and a very small amount is needed to cause infection (ID50 = 10ffu). Previous infection with rotavirus does not confer full protection. Protection is cumulative and improves with increasing number of infections and is greatest against moderate to severe disease. Unfortunately improved sanitation and public health does not affect the prevalence of RV and it is for this reason a vaccine is required to decrease the burden of disease.

Figure 2: Cross- section of a rotavirus particle

(Source. www.eurorota.net./image/crosssection)

Figure 3: Natural history of RV infection: ALL children will get at least ONE RV infection early in life

(Source.  Velaquez FR, et al. Rotavirus infection in infants as protection against subsequent infections. NEJM. 1996;335(14):1022-8.)

Clinical picture of rotavirus infection

Rotavirus most commonly affects children from 6 months to 2 years of age, with all children being infected at least once before the age of three to five years. In developing countries the peak incidence is from 6-11 months with 80 % of children being infected by one year. Neonates acquire nosocomial infection.

Rotavirus infections classically cause three symptoms – acute diarrhea, vomiting and fever. Early in the illness vomiting and fever are prominent and usually last for less than 48 hours.
The diarrhea is classically watery. It may be profuse (>10 stools per day) and commonly persist for 3-8 days. Other symptoms include anorexia, abdominal pain, irritability and lethargy.

The main clinical feature of rotavirus gastroenteritis is dehydration. Rotavirus diarrhea is more likely to be severe and to lead to severe dehydration and hospitalization and death.

The commonest climatic conditions favoring RV infection in the African studies was autumn and/or winter, followed by dry climatic conditions, and cool conditions.

Epidemiology

A.The global picture

Management of diarrhoeal disease

WHO Reccomends global use of rotavirus vaccines (Wkly Epidem Rec 2009;84:232-236. 

WHO position Paper on Rotavirus vaccines [Adobe Acrobat PDF - 294.92 KB].

Walker D, Rheingans R. Cost-effectiveness of rotavirus vaccines. Expert Review Pharmaco-economics Outcomes Research 2005;5:593-601.
  Cost-effectiveness of rotavirus vaccines (2005) [Adobe Acrobat PDF - 309.27 KB]

  Cost effectiveness of rotavirus vaccines and other interventions for diarrheal diseases: WHO meeting report 2006 [Adobe Acrobat PDF - 179.15 KB]

Glass R, Parashar U. The promise of new rotavirus vaccines. N Engl J Med 2006;354:75-77.

  The promise of new rotavirus vaccines [Adobe Acrobat PDF - 685.06 KB]

Ruiz-Palacios GM, Perez-Schael I, Velazquez FR, Abate H, Breuer T, et al. Safety and efficacy of an attenuated vaccine against severe rotavirus gastroenteritis.  N Engl J Med 2006; 354(1): 11-22.

Safety and Efficacy of a Pentavalent Human–Bovine (WC3) Reassortant Rotavirus Vaccine [Adobe Acrobat PDF - 753.07 KB]

Weekly epidemiological record [Adobe Acrobat PDF - 294.92 KB]

Rotarix international data sheet (2004) [Adobe Acrobat PDF - 66.81 KB]
This informational sheet contains prescription information for administration of Rotarix® in Latin American countries, among others.

Rotateq package insert (2006) PDF [Adobe Acrobat PDF - 131.55 KB]
This document provides information on and directions for administration of Merck’s rotavirus vaccine. Merck & Co., Inc.

Overview of Rotateq human-bovine reassortant rotavirus vaccine (2005) [Adobe Acrobat PDF - 181.84 KB]
This presentation reported on studies of the safety and efficacy of the RotaTeq® vaccine manufactured by Merck. Overview of Rotateq human-bovine reassortant rotavirus vaccine (2005)