Three Rotavirus Outbreaks in the Postvaccine Era — California, 2017

Rachel M. Burke, PhD; Jacqueline E. Tate, PhD; Nora Barin, MPH; Carly Bock; Michael D. Bowen, PhD; David Chang, MD; Rashi Gautam, PhD; George Han, MD; John Holguin, MPH; Thalia Huynh; Chao-Yang Pan, MPH; Rebecca Quenelle, MPH; Catherine Sallenave, MD; Cindy Torres; Debra Wadford, PhD; Umesh Parashar, MBBS


Morbidity and Mortality Weekly Report. 2018;67(16):470-472. 

In This Article


Although U.S. rotavirus activity has substantially declined since the introduction of rotavirus vaccine, rotavirus disease continues to occur sporadically throughout the year and epidemically in a biennial winter-spring seasonal pattern, affecting even vaccinated persons.[3] Further, as evidenced by these outbreaks as well as previously published reports, rotavirus affects not only young children, but also adults, especially those in congregate living settings.[5,6]

Although these outbreaks represent a small proportion of U.S. rotavirus outbreaks, and are not necessarily representative of all outbreaks, they illustrate some general characteristics of rotavirus outbreaks in the postvaccine era. The first outbreak, in the child care center, was characterized by comparatively mild illness in otherwise healthy children and illustrates that rotavirus outbreaks do occur in the postvaccine era, even among healthy, vaccinated populations. Current rotavirus vaccines are highly effective against severe diarrheal illness, but they do not necessarily prevent infection or milder disease. Thus, rotavirus disease and outbreaks can occur even in populations where vaccination coverage is high.

The second outbreak, in an adult assisted living and memory care facility, demonstrated that rotavirus can and does cause illness in adult populations and can spread easily among adults living in close quarters, such as nursing homes. Though adults do not receive rotavirus vaccine, research has indicated that rotavirus vaccination of children might have an indirect protective effect in the adult population.[7] As use of multipathogen PCR testing increases, there might be more detection of rotavirus outbreaks in adult populations. Rotavirus outbreaks are sometimes initially suspected to be norovirus, but rotavirus should not be ruled out as a causative agent because of the age of the affected population. Nonetheless, the public health recommendations are similar for both norovirus and rotavirus. Hand hygiene, cohorting and isolation, and surface disinfection with appropriate products should be emphasized. Cleaning surfaces with soap and water followed by a 5-minute application of 1000–5000 ppm chlorine solution (5–25 tbsp [2.5–12.5 oz] of household bleach [5.25% sodium hypochlorite] per gallon of water) or other disinfectant registered as effective against norovirus by the EPA is appropriate for both pathogens.[8,9]

The third outbreak also occurred among children; however, in contrast to the first outbreak, it affected an already vulnerable population with low vaccination coverage and was associated with the highest attack rate among the three outbreaks, as well as one fatality. Reasons for nonvaccination among children in the facility were not ascertained; however, most patients at the facility had spent time in neonatal and pediatric intensive care units, where use of live viral vaccines is discouraged,[1] and many were too old to begin rotavirus vaccine after discharge. Additional research might be necessary to evaluate the risks and benefits of this practice.

Although the impact of rotavirus vaccines against various commonly circulating strains has been well documented, rotavirus outbreaks will continue to occur, even among highly vaccinated populations. Although genotype G12P[8] was detected in samples from all three outbreaks, this likely reflects the fact that G12P[8] has been the most common circulating strain in the United States in recent years.[10] Both currently available rotavirus vaccines have demonstrated effectiveness against this strain;[2] however, because rotavirus vaccination coverage lags behind that of other childhood vaccines, many children remain susceptible to severe rotavirus disease. Public health practitioners, as well as clinicians, should continue to consider rotavirus as a suspected agent in cases of AGE across all ages and should promote rotavirus vaccination among eligible infants according to CDC recommendations.