Rotavirus Infections and Vaccines

Abstract

Rotaviruses are the most common cause of severe gastroenteritis in children. By 5 years of age virtually every child worldwide will have experienced at least one rotavirus infection. This leads to an enormous disease burden, where every minute a child dies because of rotavirus infection and another four are hospitalized, at an annual societal cost in 2007 of $US2 billion. Most of the annual 527 000 deaths are in malnourished infants living in rural regions of low and middle income countries. In contrast, most measurable costs arise from medical expenses and lost parental wages in high income countries. Vaccines are the only public health prevention strategy likely to control rotavirus disease. They were developed to mimic the immunity following natural rotavirus infection that confers protection against severe gastroenteritis and consequently reduces the risk of primary healthcare utilization, hospitalization and death. The two currently licensed vaccines--one a single human strain rotavirus vaccine, the other a multiple strain human-bovine pentavalent reassortant rotavirus vaccine--are administered to infants in a two- or three-dose course, respectively, with the first dose given at 6-14 weeks of age. In various settings they are safe, immunogenic and efficacious against many different rotavirus genotypes. In high and middle income countries, rotavirus vaccines confer 85-100% protection against severe disease, while in low income regions of Africa and Asia, protection is less, at 46-77%. Despite this reduced efficacy in low income countries, the high burden of diarrheal disease in these regions means that proportionately more severe cases are prevented by vaccination than elsewhere. Post-licensure effectiveness studies show that rotavirus vaccines not only reduce rotavirus activity in infancy but they also decrease rates of rotavirus diarrhea in older and unimmunized children. A successful rotavirus vaccination program will rely upon sustained vaccine efficacy against diverse and evolving rotavirus strains and efficient vaccine delivery systems. The potential introduction of rotavirus vaccines into the world's poorest countries with the greatest rates of rotavirus-related mortality is expected to be very cost effective, while rotavirus vaccines should also be cost effective by international standards when incorporated into developed countries immunization schedules. Nonetheless, cost effectiveness in each country still depends largely on the local rotavirus mortality rate and the price of the vaccine in relation to the per capita gross domestic product.

Economics and financing of vaccines for diarrheal diseases

“…In addition, it is estimated to cause 111 million gastroenteritis episodes for which care is not sought. 59 Globally, in 2004, rotavirus accounted for 527 000 deaths (95% CI: 475 000-580 000) among children <5-y-old; more than half of these deaths were in 6 countries (India, Nigeria, Congo, Ethiopia, China, and Pakistan), with 23% in India alone. 60 Economic burden: high income country Additional studies provide more detailed disease burdens for developed countries from 2004 to 2009.…”

“…11,13,14,31,61 While the mortality is rare in high income countries, the economic burden is considerable. 59 Rotavirus cost €166 to €473 in the primary care setting and €1525 to €2101 in the hospital setting in areas for Belgium, France, Germany, Italy, Spain, Sweden, and the UK (societal costs per case, in 2006 values). There are many studies determining the cost of rotavirus for many developed countries, several focusing on children less than 5 y of age.…”

Maternal-child health

“…However, in less developed regions such as South America and Africa they reached only 25% -50%. In addition to strains that are common, several uncommon strains have been found in specific areas such as G5P [8] in Brazil, G8P [6] in Africa, G10P [11] and G12P [6] in India (Grimwood & Lambert, 2009). …”

“…The risk of rotavirus infection increases among groups of low socioeconomic conditions, malnutrition-effected people, infants with low birth weight and preterm birth, persons suffering from compromised immunity and co-infection with other enteric pathogens (Grimwood & Lambert, 2009). …”

Non-uptake of childhood vaccination among the children of HIV-infected mothers in sub-Saharan Africa: A multilevel analysis

“…It is expected that good vaccine uptake in these countries will be cost-effective on the long run and this depends largely on the cost of vaccination programme with respect to GDP. 14 Vaccination plays an important role in economic growth. It has an impact on country’s healthcare with resultant reduction in mortality and morbidity, thereby contributing to the GDP.…”