Data from: Three-level mixed-effects logistic regression analysis reveals complex epidemiology of swine rotaviruses in diagnostic samples from North America

Rotaviruses (RV) are important causes of diarrhea in animals, especially
in domestic animals. Of the 9 RV species, rotavirus A, B, and C (RVA, RVB,
and RVC, respectively) had been established as important causes of
diarrhea in pigs. The Minnesota Veterinary Diagnostic Laboratory receives
swine stool samples from North America to determine the etiologic agents
of disease. Between November 2009 and October 2011, 7,508 samples from
pigs with diarrhea were submitted to determine if enteric pathogens,
including RV, were present in the samples. All samples were tested for
RVA, RVB, and RVC by real time RT-PCR. The majority of the samples (82%)
were positive for RVA, RVB, and/or RVC. To better understand the risk
factors associated with RV infections in swine diagnostic samples,
three-level mixed-effects logistic regression models (3L-MLMs) were used
to estimate associations among RV species, age, and geographical
variability within the major swine production regions in North America.
The conditional odds ratios (cORs) for RVA and RVB detection were lower
for 1–3 day old pigs when compared to any other age group. However, the
cOR of RVC detection in 1–3 day old pigs was significantly higher (p
< 0.001) than pigs in the 4–20 days old and >55 day old age
groups. Furthermore, pigs in the 21–55 day old age group had statistically
higher cORs of RV co-detection compared to 1–3 day old pigs (p <
0.001). The 3L-MLMs indicated that RV status was more similar within
states than among states or within each region. Our results indicated that
3L-MLMs are a powerful and adaptable tool to handle and analyze
large-hierarchical datasets. In addition, our results indicated that,
overall, swine RV epidemiology is complex, and RV species are associated
with different age groups and vary by regions in North America.